News this Week

Science  08 Apr 2005:
Vol. 308, Issue 5719, pp. 174
  1. U.S. PATENT LAW

    Case Probes What's Fair Game in the Search for New Drugs

    1. Eli Kintisch

    How much freedom does a drug company have to use someone else's patented research tools in the course of developing new therapies? This month, the U.S. Supreme Court will hear oral arguments in a patent case between a German pharmaceutical giant and a small U.S. biomedical company involving a 20-year-old federal law originally passed to speed generic drugs to market. Legal experts say that the court's answer to that question could alter the ground rules for intellectual property claims not just in the pharmaceutical industry but also across many areas of basic research.

    On 20 April, the high court will hear arguments pitting Merck KGaA (not affiliated with the U.S.-based Merck & Co.) against the Plainsboro, New Jersey-based Integra. The 9-year-old dispute rests upon an interpretation of a 1984 federal law—known as the “FDA safe harbor”—that gives drug researchers an exemption from patent liability for work “reasonably related” to the Food and Drug Administration (FDA) approval process. The outcome of the case will hinge on the court's definition of “reasonably related” research. Merck's position is supported in briefs filed by the U.S. government, big pharma, and the seniors' lobbying group AARP. Arrayed on the other side are small and large biotech companies that primarily sell patented tools to scientists.

    Congress created the safe-harbor exemption in 1984 so that companies making generic drugs could work with patented materials in preparing FDA applications without having to wait until the patent expired. Federal courts have since steadily expanded the kinds of research covered by the exemption to include research on novel drugs and medical devices.

    The trigger for the legal battle was a 1994 discovery by David Cheresh, a cell biologist at the Scripps Research Institute in La Jolla, California, that molecules that bind to a surface protein called αvβ3 inhibit blood vessel growth, or angiogenesis (Science, 22 April 1994, p. 569). Merck soon cut a deal with Cheresh and Scripps to begin to identify drug candidates in animal models and, as the agreement stated, “satisfy (FDA) regulatory requirements.”

    Trigger.

    David Cheresh's discovery that blocking αvβ3 (left) inhibits angiogenesis led to a search for new drugs—and a patent dispute.

    CREDITS (LEFT TO RIGHT): J. P. XIONG ET AL., SCIENCE 293, 1745 (2001); THE SCRIPPS RESEARCH INSTITUTE

    A small firm called Telios, though, held patent rights on the use of peptides containing a particular sequence, known as RGD, that binds to αvβ3. Cheresh's work involved RGD peptides. Telios sued in U.S. District Court, soon after which Integra bought the intellectual property from Telios. In 2000, the jury found that at least one and as many as 180 Merck experiments between 1994 and 1998—most involving testing how effectively several compounds starved tumors on chicken embryos—had infringed Integra's patents and awarded Integra $15 million. An appellate court upheld the ruling in 2003, calling Cheresh's work “preclinical” and not tied to FDA approval of any drug. By narrowing the exemption's scope, says patent attorney Denise DeFranco of Foley Hoag LLP in Boston, the ruling “kind of shook up some established expectations.”

    Not according to Integra's attorneys, who say that the appellate court was simply affirming the rights granted to any patent holder. “The biotech industry is all about new tools,” says Mauricio Flores, an attorney for Integra at McDermott Will & Emery LLP in Washington, D.C. In a supporting brief, biotech companies Affymetrix and Invitrogen say that a broad interpretation of the safe harbor provision would undermine their ability to earn licensing revenue for innovations that lay the groundwork for new medicines.

    The appeals court ruled that the Scripps-Merck experiments amounted to “new drug development activities.” Integra lawyers point out that chicken embryos—unlike mice, for example—are not considered predictive enough of human health for FDA requirements. Merck is trying to use the safe harbor “as a cover for [patent] infringing work,” Integra argues in its brief. But Merck says the embryo work addressed FDA requirements regarding efficacy and other metrics. Merck maintains that the studies came after Cheresh had “a viable drug candidate” in hand and that the safe harbor “embraces any information that a drug innovator could reasonably expect to submit to the FDA in connection with any application.”

    Several biotech attorneys believe that the appeals court erred in ruling that Cheresh's “preclinical” work was not part of the FDA approval process. “Limitation of the safe harbor to ‘clinical’ experiments would ignore the extensive preclinical data required by the FDA,” argues the American Intellectual Property Law Association in its brief.

    Some patent attorneys are worried that the high court, regardless of its ruling on the safe harbor, might narrow a related practice that provides academics and others pursuing basic research with an exemption for “experimental use.” Courts have narrowed its applicability over the last 2 decades, most recently in a case that pitted Duke University against a former professor, laser scientist John Madey (Science, 3 January 2003, p. 26).

    An appellate judge mentioned the research exemption in her dissent, raising the possibility that the high court could inadvertently confirm a restrictive new standard. “That's the worst fear,” says Josh Sarnoff, a law professor at American University in Washington, D.C., and an attorney for the Consumer Project on Technology, which has filed a brief in support of Merck's position.

  2. INFECTIOUS DISEASES

    North Korea Collaborates to Fight Bird Flu

    1. Dennis Normile

    World health officials are encouraged by two developments in North Korea. First was confirmation earlier this week that an outbreak of avian influenza in that isolated country was not due to the dreaded H5N1 subtype. Second, and perhaps equally important for long-term efforts to monitor emerging diseases, was North Korea's willingness to cooperate with global animal and human health surveillance efforts. The country notified the United Nations Food and Agricultural Organization (FAO) of the outbreak and allowed FAO experts to confirm the virus as an H7 subtype. Korean officials also informed the World Health Organization (WHO). Such exchanges, unthinkable a decade ago, suggest that the secretive nation is increasingly willing to participate in global health protection efforts.

    “I think they know the seriousness of avian influenza, so I'm rather positive in hoping for a continuation of [cooperation] in the future,” says Hans Wagner, senior animal health officer for FAO's regional office in Bangkok.

    Such cooperation is vitally important in watching for any evolution in the H5N1 virus. Since December 2003, the virus has devastated poultry flocks throughout Asia and has claimed at least 49 human lives. Almost all human infections have been traced to contacts with infected poultry. But health officials worry that if the H5N1 virus acquires the ability to spread easily among humans, it could set off a deadly pandemic.

    Despite a long history of self-imposed isolation, North Korea has increasingly been cooperating with international agencies over the past decade. The World Food Program and WHO have both expanded their work in the country since they opened offices there in 1995 and 2001, respectively. And even before North Korea had suffered any major outbreaks of avian flu, last fall it joined an FAO network of east Asian countries set up to cooperate in fighting H5N1, says Wagner. North Korean veterinary officials have attended regional FAO symposia on avian influenza, and FAO is planning a May workshop on surveillance for North Korean animal health officials.

    North Korea officially informed the FAO regional network of the avian influenza outbreak on 27 March, 2 weeks after rumors appeared in the South Korean press. Wagner, who arrived on 29 March, says North Korean officials allowed an FAO expert to verify tests suggesting the virus was an H7 subtype. Wagner's hosts also took him to the index farm and described their culling methods. “We can work with and collaborate with DPRK authorities,” Wagner says.

    Diego Buriot, a WHO special adviser on communicable diseases, calls North Korea's decision to request technical assistance from FAO “a very positive step,” adding that “WHO is also ready to provide expertise if requested by the government.”

    Wagner is counting on further cooperation. Although reassured that the virus is not H5N1, he notes that H7 subtypes remain a serious threat to poultry—and thus to food availability—in the impoverished country. An H7N7 avian flu outbreak in the Netherlands in 2003 claimed one human life and sickened dozens. Wagner says the specific N subtype of the North Korea virus has yet to be determined, but this is the first recorded instance of an H7 virus in Asia. FAO experts will be working with their North Korean counterparts to try to trace where the virus came from and how to prevent further spread. The exercise may turn out to be a dry run in case H5N1 does turn up in North Korea.

  3. CONFLICT OF INTEREST

    Scientists, Societies Blast NIH Ethics Rules

    1. Jocelyn Kaiser

    New ethics rules at the National Institutes of Health in Bethesda, Maryland, unfairly punish all employees for the sins of a few and will isolate NIH researchers from the scientific community. That's the gist of roughly 1000 comments by NIH employees and many scientific societies submitted by a 4 April deadline to the Department of Health and Human Services (HHS) in Washington, D.C. Even before the comments were in, a handful of top NIH researchers had announced that the rules had prompted them to leave NIH. The latest is National Institute on Deafness and Other Communication Disorders Director James Battey, who says a ban on owning biomedical stocks put him in an impossible position (see p. 197).

    NIH Director Elias Zerhouni unveiled the strict new HHS ethics regulations in February after questions arose about a handful of NIH researchers who were consulting for companies. Many comments say reforms were needed, but the rules go too far. They are “not carefully aligned with risk” and “will have a significant negative impact on the progress of biomedical research as a whole,” writes the Federation of American Societies for Experimental Biology (FASEB) in Bethesda, Maryland. Thirty-nine of NIH's 43 National Academy of Sciences members signed a letter calling the rules “unfair,” “totally unjustified,” and “a serious threat to the intramural research program.”

    The stock rule has drawn the most fire. It bans about 6000 senior employees and their families from owning any stock in drug, biotech, or medical-device companies. Others can hold no more than $15,000 in a single medical company. Hundreds of comments, including some from researchers at universities, argue that the order to divest will cause financial hardship for many employees, as well as dissuade outside researchers from coming to NIH. The Association of American Medical Colleges (AAMC) in Washington, D.C., urges NIH to tailor the prohibition to officials with decision-making power, as proposed by NIH's Assembly of Scientists (homepage.mac.com/assemblyofscientists).

    A smaller number of comments question the rule's ban on consulting for industry. One NIH scientist noted with chagrin that he had to turn down a company's request to help figure out the mechanism of a new psoriasis drug, a project unrelated to his work.

    Scientific societies worry about restrictions on NIH scientists' professional activities and call for the rules to be revised quickly or withdrawn. FASEB and AAMC, for instance, argue that rules banning service on boards shouldn't apply to society boards. They also say NIH scientists should be allowed to give single lectures, which are common at medical schools. These and other organizations urge NIH, which now strictly limits cash awards of more than $200 to “bona fide” awards, to complete that list; the lack of guidance has already caused problems for some societies. A coalition of advocacy nonprofits called the Cancer Leadership Council in Washington, D.C., which relies on voluntary service from NIH employees, argues that it should be exempt, too.

    A recent e-mail from NIH's Assembly of Scientists underscores the breadth of the rules, noting that NIH approval is now required for “any outside employment, whether or not for compensation, or any self-employed business activity,” even singing in a choral group or selling artwork: “It suggests the NIH owns our lives away from work.”

    HHS has already made a few slight changes to the rules, exempting temporary researchers from the stock limits and extending until October the deadline for divesting. The agency has said it expects to make any further revisions by next February.

  4. LIVERMORE NATIONAL LAB

    Settlement in Bias Case Could Unravel

    1. Yudhijit Bhattacharjee

    Lawrence Livermore National Laboratory has agreed to pay a total of $1.2 million to settle a suit alleging discrimination against Asian-American scientists and engineers at the lab. But several plaintiffs say the settlement is too small and discriminates against women; it could be scrapped if enough scientists reject the terms.

    The lawsuit, filed in 2001, alleges unfair treatment and inequalities in salary and promotion based on race. The class-action suit was filed by nine individuals representing 460 current and retired employees at the California weapons lab, which is run by the University of California (UC) for the Department of Energy (DOE). Under the settlement agreement, which was approved on 22 March by the Alameda County Superior Court, the employees would split $765,000 and UC would also pay up to $350,000 of their legal costs. Each of the nine persons named in the original suit would get an additional $15,000. The settlement does not admit that discrimination occurred, and Livermore officials declined comment.

    Wrong choice.

    Kalina Wong says the Livermore settlement makes people pick “whether you're a woman or you're an Asian.”

    CREDIT: K. WONG

    Five of the nine named plaintiffs have already rejected the terms as too stingy. Michael Sorgen, the attorney for those five, says the average compensation of $1700 per employee is “paltry compared to the years of depressed salaries and blocked promotions” for many workers. One particularly egregious element, Sorgen says, is that most female employees, who make up roughly a quarter of the class, wouldn't be able to collect anything. That's because the settlement stipulates that any sums awarded to individuals from an earlier sex-discrimination suit, which UC settled in December 2003, would be deducted from the amount they are to receive in this case. In the sex-discrimination suit, UC agreed to pay $10 million to 3200 women who had worked at the lab during a 6-year period and give a 1% raise to 2500 current female employees (Science, 5 December 2003, p. 1641).

    One plaintiff, Kalina Wong, says the settlement represents continuing discrimination against women. “They're saying you can face discrimination as an Asian, you can face discrimination as a woman, but if you're both, you must pick whether you're a woman or you're an Asian,” says Wong, a computer scientist who retired from the lab in 2002. She's the only woman among the nine plaintiffs and the only retiree opposed to the settlement.

    The four backing the settlement—all retirees—say they are exhausted after 3 years of litigation. “The lab would just have continued dragging its feet,” says Richard Yamauchi, a programmer. He also concluded that the lawsuit would not alter what he sees as a discriminatory environment. “Asian employees will continue to be discriminated against because the people who discriminated against us are still there, and they are passing on their behaviors to future managers,” he says. “There is nothing to break the cycle.”

    Apart from the financial issues, the settlement calls for “a pay, promotion, and rank equity study” of Asian scientists and engineers at the lab every year for the next 3 years.

    The affected workers must decide by 31 May whether to participate in the settlement, which goes back to the judge on 21 June. If 10% of them opt out, the university has the right to pull out, too. Sorgen says his clients plan to press ahead regardless of the outcome.

  5. POSTDOCS

    Care and Feeding Pays Off, Survey Finds

    1. Yudhijit Bhattacharjee

    Careful tending of a young plant, every gardener knows, is more likely to yield a bountiful harvest. A new survey of 7600 postdocs shows that axiom also applies to the research lab.

    The survey, conducted by the scientific society Sigma Xi and released this week (sigmaxi.org), suggests that a well-structured environment for postdocs pays off in greater productivity, more so than do salary and benefits. That finding, says its author, backs up the point that postdoctoral associations and their advocates have been making for years: Treat us with respect, rather than just as a pair of hands, and we'll deliver.

    “What really counts is not the money but the [postdoc] experience,” says Geoff Davis, who led the study. “[Principal investigators] need to realize that they are obligated to provide training to their postdocs, and universities and funding agencies need to ensure that PIs are fulfilling that obligation.”

    With support from the Alfred P. Sloan Foundation in New York City, Davis and his colleagues e-mailed a questionnaire to roughly 40%—some 22,000—of the postdocs working at 46 institutions. The list included 18 of the top 20 U.S. academic employers and the largest government employer, the National Institutes of Health in Bethesda, Maryland. Administrative oversight included elements such as an office to manage postdoctoral affairs and formal review of postdocs' performance. Davis also asked about formal and informal avenues for honing postdocs' communication, management, and other professional skills.

    Management advantage.

    Structured oversight has a greater impact on postdoc performance than does salary.

    SOURCE (LEFT): THE SIGMA XI POSTDOC SURVEY; (RIGHT) © ROYALTY-FREE/CORBIS

    The researchers then correlated these measures with the number of peer-reviewed publications and similar indices of success. The results showed that there was a stronger correlation between administrative oversight and productivity than there was between salary and productivity. “Having a comprehensive career plan, formal reviews, and good training produces an improvement in the postdoc's satisfaction level that is equivalent to a $20,000 raise,” says Davis. Postdocs in well-structured positions also seem to report fewer conflicts with their advisers.

    The findings reaffirm what postdocs have been saying for a decade, says Alyson Reed, executive director of the National Post- doctoral Association in Washington, D.C., one of the sponsors of the study. “Postdocs make a financial sacrifice in the hope of advancing their career prospects,” she says. “They have a greater chance of achieving that goal if they sit down with the PI to develop a formal plan and then use that plan to review progress.”

    A handful of institutions already have policies to foster that kind of experience, and others are recognizing their value. “It's to everyone's advantage: the institution, the PI, and the postdoc,” says Joan Lakoski, a senior administrator at the University of Pittsburgh Health Sciences Schools in Pennsylvania, which this fall will require its PIs to prepare an “Individual Development Plan” for their postdocs. PIs will also have to conduct an annual performance review. “The process could easily be viewed as another tiresome piece of paperwork mandated by the university,” says Lakoski. “But it's really an opportunity to improve scientific productivity.”

  6. POSTDOCS

    IRS Takes Bite out of NIH Fellows' Paychecks

    1. Beryl Lieff Benderly*
    1. Beryl Lieff Benderly covers postdoctoral issues for Science's Next Wave (http://www.nextwave.org/).

    Almost 5000 postdoctoral scholars supported by National Institutes of Health (NIH) fellowships took a 7.65% pay cut this week, thanks to a new U.S. tax regulation. The change, which also requires their institutions to pay more to the government, exacerbates a long-running disagreement between NIH and the Internal Revenue Service (IRS) over the employment status of this slice of the U.S. postdoc population.

    The IRS regulation, which went into effect 1 April, puts the squeeze on postdocs funded by the Ruth L. Kirschstein National Research Service Awards (NRSA) and some other fellowships by redefining who qualifies for a student exemption that shields the income earned from certain campus jobs. The rule requires employers, mostly universities, to begin withholding FICA (Social Security) and Medicare taxes from their paychecks.

    Historically, NIH has argued that its NRSA postdocs are trainees rather than employees. Under that classification, universities do not have to offer postdocs employee group health insurance and other typical work benefits. A NIH spokesperson estimated that there were 4700 postdocs on NIH training grants and similar fellowships in fiscal year 2004. The new rule does not affect the estimated 50,000 postdocs paid out of R01s and other research grants to principal investigators, who have long been classified as employees, with FICA and Medicare taxes deducted from their pay.

    In statements on its Web site, NIH makes it clear that it disagrees with the new rule. It maintains that Kirschstein NRSA postdocs are not employees and that the new IRS regulation should not apply to them. The statement goes on to add that “it is, therefore, inappropriate and unallowable for institutions to charge costs associated with employment (such as FICA, workman's compensation, or unemployment insurance) to the fellowship award.” It also makes clear who is actually calling the shots. “NIH takes no position on the status of a particular taxpayer, nor does it have the authority to dispense tax advice,” the NIH Web site explains. “The interpretation and implementation of the tax laws are the domain of the IRS.”

    Most universities appear to have gotten the message. “We immediately talked to our internal counsel and then our outside counsel, [who say] all postdocs, medical residents, and medical interns have to pay FICA,” says Joel Oppenheim, senior associate dean for biomedical sciences at New York University School of Medicine. Paying the employer's share of FICA and Medicare taxes for the medical school's 300-plus postdocs, he notes, about $3300 per individual, also affects the university's bottom line. “That's over a million bucks a year for us,” says Oppenheim.

  7. PALEOANTHROPOLOGY

    Facelift Supports Skull's Status as Oldest Member of the Human Family

    1. Ann Gibbons

    For paleoanthropologists seeking the roots of humanity, a striking skull discovered among the shifting sand dunes of the Djurab Desert of Chad in 2001 was a dramatic find, offering the first glimpse of a primate alive at the dawn of humankind. But although the nearly 7-million-year-old skull was introduced as that of the oldest known hominid, rivals soon argued that it looked more like a gorilla ancestor than a human (Science, 12 July 2002, p. 171). Now the skull of Sahelanthropus tchadensis, nicknamed Toumai, is back in headlines again. It appears in Nature this week with two new looks—a three-dimensional virtual reconstruction and a clay bust on the cover, a nod to creation myths that humans were made of clay.

    Fresh fossils of teeth and jaw fragments plus a state-of-the-art analysis of the virtual skull show that Toumai is indeed a hominid, or a member of the lineage that includes humans and our ancestors but not other apes, argues paleontologist Michel Brunet of the University of Poitiers, France, leader of the team that discovered Toumai. The new analysis also suggests that Sahelanthropus might have walked upright, a traditional marker of being a hominid. “It is quite clear Toumai is a hominid,” says Brunet. “It is not a gorilla.”

    Other researchers applaud the sophistication of the reconstruction, performed by a team led by neurobiologist Christoph Zollikofer of the University of Zurich (UZ), Switzerland. “What a facelift! This beautiful reconstruction is the outcome of high technology combined with a deep understanding of anatomy,” says Tel Aviv University paleo- anthropologist Yoel Rak. But some caution that although the new evidence helps build the case that Toumai was a hominid, its identity is far from certain. “I'd be happy to put it down as [a very early] hominid,” says anatomist Fred Spoor of University College London. “But it's a time we know so little about that I am still skeptical.”

    Family portraits?

    A computer reconstruction (left) suggests that Toumai (reconstructed in clay, right) is the oldest known human ancestor.

    CREDITS: M.P.F.T. (ARTIST'S RECONSTRUCTION: E. DAYNES)

    Brunet took the skull to Zollikofer and UZ anthropologist Marcia Ponce de Leon, known for their sophisticated high-resolution computed tomography scans and analyses. The skull had been crushed under a sand dune and distorted, and the researchers were able to erase the ravages of time in the computer, using three-dimensional computer graphics tools to rebuild it piece by piece. The resulting face is taller, with a bit more snout than seen in the original.

    Zollikofer and Ponce de Leon then identified 39 landmarks on the skull, which they used to compare it directly with the skulls of fossil hominids, two chimpanzee species, and gorillas. They found that the shape of Toumai's skull “falls exactly within the hominids,” says Zollikofer. No matter how they tried, they could not force the pieces of the skull to fit into the shape of a chimpanzee or gorilla skull without deforming it grossly. “It is impossible to reconstruct Toumai as an ape,” he says.

    Several researchers find the virtual evidence compelling. “I was worried about the distortion, but they are great at building virtual reconstructions that test hypotheses about how these fossils looked,” says anthropologist John Kappelman of the University of Texas, Austin.

    The reconstruction also revealed new evidence that suggests Sahelanthropus walked upright. A virtual line from the top to the bottom of Toumai's eye orbit makes roughly a right angle with another virtual plane at the base of the skull. That right angle is also seen in humans, reflecting that the head sits directly atop a vertical spine when walking upright. The angle between the planes is much smaller in the quadrupedal apes studied, reflecting that the head sits in front of a more horizontal neck, explains co-author Daniel Lieberman of Harvard University. Thus the team concludes that Sahelanthropus “might” have been bipedal. “I'm the first to say you need postcranial fossils to be 100% sure, but it's darned hard to think how Toumai could not have walked upright,” says Lieberman.

    However, others caution that skulls don't walk upright by themselves, and that lower limbs are needed to prove this hallmark trait. Until Brunet and his colleagues describe postcranial fossils, paleoanthropologist Milford Wolpoff of the University of Michigan, Ann Arbor, sees Toumai as an ape, citing what he calls apelike features in the base of the neck.

    More fossils also are needed to settle the question of how Sahelanthropus is related to later hominids. “There is still insufficient fossil evidence to determine whether there were one, two, or more hominid species lineages between 5 [million] and 7 million years ago in Africa,” says paleoanthropologist Tim White of the University of California, Berkeley.

    Brunet declines to comment on reports that his team has also discovered a partial thighbone, but he adds cryptically: “Surely postcranials will be coming in the future. I will be very, very surprised if it is not bipedal.”

  8. PALEOCLIMATOLOGY

    Cosmic Dust Supports a Snowball Earth

    1. Richard A. Kerr

    Answering questions about Earth's climate of more than half a billion years ago can be a challenge—even questions as stark as whether land and sea were completely coated by ice from pole to pole. Indeed, the revival of the Snowball Earth hypothesis almost 7 years ago has bogged down of late, as paleoclimatologists have failed to turn up unequivocal evidence that ice enrobed our planet.

    But on page 239 of this issue, a group of geochemists offers a new snowball marker: the element iridium, which continually rains down on us from space. They say they found so much iridium deposited at the end of a glaciation 635 million years ago that the planet must have been frozen pretty much solid for 12 million years straight. “I think this is a very exciting discovery,” says geochemist Frank Kyte of the University of California, Los Angeles. Like any new tool, iridium needs some more work, but “I'm sure it will invoke a lot of discussion.”

    No accident.

    The discovery of a spike of cosmic iridium (green line) at the end of an ancient ice age (top of blue glacial sediments) suggests that ice covered the planet.

    CREDIT: ADAPTED FROM BERND BODISELITSCH ET AL.

    This isn't iridium's first appearance as a timekeeper. But geochemists Bernd Bodiselitsch and Christian Koeberl of the University of Vienna, Austria, and their colleagues took a new tack when they analyzed 44 elements including iridium along three cores drilled by copper miners in Zambia and the Democratic Republic of the Congo. Bodiselitsch and his colleagues figured that on an iced-over world, the iridium-rich meteoritic dust that rains onto Earth would accumulate until the snowball ended in a sudden meltdown, as climate modelers believe would happen. All the iridium accumulated in the ice would then be deposited in a single, thin layer of marine sediment. The more iridium deposited at the end of a snowball, the longer the snowball had gone on.

    In the first few centimeters of sediment laid down on top of glacial sediments, Bodiselitsch and colleagues indeed found sharp spikes in the abundance of iridium. A spike showed up in all three cores at the end of the Marinoan glaciation about 635 million years ago and in two cores at the end of the earlier Sturtian glaciation about 710 million years ago. The iridium could conceivably have been homegrown—from a volcanic eruption or concentrated from crustal rock by some geochemical process—but several other elements were present in proportions typical of meteorites, not the crust. And the proportion of iridium to some other elements suggested that geochemical processing had not concentrated the iridium, they concluded. If meteoritic material was falling to Earth 635 million years ago at anything like the rate it has during the past 80 million years, the group calculates, the Marinoan glaciation lasted 12 million years, give or take 3 million years.

    The ice was all around?

    A true Snowball Earth would have coated the globe with ice.

    CREDIT: PHOTOS.COM

    If the Marinoan ice age managed to save up 12 million years' worth of extraterrestrial iridium, it must have iced over the entire planet, researchers agree. The alternative to Snowball Earth has been Slushball Earth (Science, 26 May 2000, p. 1316). Rather than pole-to-pole ice, some paleoclimate modelers have suggested that Marinoan glaciation might have left tropical oceans ice-free and still produced glacial deposits near equatorial continents. But a slushball would have melted down within something like a million years as volcanoes belching carbon dioxide fueled a growing greenhouse. “It's hard to see what would keep a slushball around for 10 [million] or 20 million years,” says climate modeler Raymond Pierrehumbert of the University of Chicago. And even if a slushball did last, its glaciers—unlike those of a snowball—would continually flow down to the sea, steadily depositing iridium, not producing a spike of it.

    Geochemists are excited but naturally cautious. “Iridium is a strong indicator of extraterrestrial material,” says Bernhard Peucker-Ehrenbrink of the Woods Hole Oceanographic Institution in Massachusetts. “However, it is just one of a series of useful tracers.” He and others, he expects, will be pursuing other extraterrestrial tracers such as isotopes of helium and of osmium to test the claim of a Snowball Earth. Prompting such testing “is what good, interesting, provocative papers should do,” he says.

  9. SCIENCE IN LIBYA

    From Pariah to Science Powerhouse?

    1. John Bohannon*
    1. John Bohannon is a science writer based in Berlin.

    Now that international sanctions on Libya have been lifted, Muammar Gaddafi is inviting outsiders to help create a “northern star” of science and technology in Africa

    TripoliWhen Mustafa Eteer, a doctor born in Libya, returned from Canada to visit his mother in this breezy Mediterranean city 4 years ago, he went through a life-changing experience. To his shock and dismay, his mother, who had been hospitalized for a minor illness, died of infections that would have been easily prevented in the West. The public health failure was “not a question of money,” says Eteer. Oil revenue has provided Libyans the highest per capita income on the continent, even during the 12 years when the country was under international sanctions for its support of terrorism. Rather, he says, the isolation led to “a lack of knowledge and expertise,” which in turn resulted in unnecessary suffering. Eteer vowed to bring modern medical science to Libya—although at the time, he had no idea how he would do it.

    Today, thanks to a new drive to boost science by the nation's longtime ruler Colonel Muammar Gaddafi and the lifting of the last of the sanctions in 2004, Eteer may have a chance to realize his dream. He is overseeing the construction of a $100 million medical science complex on the outskirts of Tripoli that is being held up as an example of the nation's commitment to knowledge. The aim of the Center for Infectious Disease Control in Africa (CIDCA) is grander than Eteer's initial vision: Gaddafi wants it to tackle disease not just in Libya but throughout Africa. However, a dark shadow still hangs over this project and Libya's other scientific aspirations: With the government's acquiescence, a Libyan court has sentenced to death a group of foreign medics on conspiracy charges that outside experts say are based on bogus science (see sidebar on p. 184). The case could be a big impediment to enticing foreign scientists to work here.

    The timing could not be worse for Libya's ambitions. As it seeks to dispel old ghosts, the country has embraced a goal of becoming a nexus of scientific and technical collaboration. CIDCA is just the first tangible feature of this vision. Gaddafi began setting the change in motion when he announced his abandonment of weapons of mass destruction (see p. 185) and agreed to pay billions of dollars in compensation for alleged terrorist attacks. Now, to the delight of Libya's academic community, Gaddafi is trying to position Libya as a leading light for the rest of Africa, in part by providing centers of scientific and educational excellence, including a new observatory for astronomers. Bankrolling these ventures is the Gaddafi Foundation, a huge private fund of undisclosed value created by the Libyan ruler and directed by his son Saif.

    “The sanctions killed Libyan science,” says Ali Al-Hamdy, an ecologist who directed his country's Marine Biology Center until last year. “It was nearly impossible to go to conferences, publish in journals, or get equipment. But now, everything is possible.”

    Elite site.

    The campus of Libya's Center for Infectious Disease Control in Africa boasts tennis courts and irrigated landscaping.

    CREDIT: J. BOHANNON/SCIENCE

    A CDC for Africa

    Beneath the vaulted arcades of the European-styled boutiques in Tripoli's Green Square, immigrant workers sweep up trash in preparation for a state ceremony. Most laborers like these are here illegally, having crossed the dangerous expanse of the Sahara to escape violence and poverty in Sudan, Chad, Niger, and farther south. With them comes the specter of diseases that Libya has until now largely escaped, such as AIDS. Libya's new focus on pan-African diseases is therefore built in part on enlightened self-interest.

    “The Libyans usually say they have no AIDS,” says Vittorio Colizzi, a molecular pathologist at Tor Vergata University in Rome who has collaborated for several years with Libyan epidemiologists, “but it has definitely been here for years and is increasing.” Others agree that the risk is real. “All of northern Africa has the right ingredients for an AIDS epidemic, including poverty, civil wars, and large refugee populations,” says Mark Kline, a virologist who directs the International Pediatric AIDS Initiative at Baylor College of Medicine in Houston, Texas. There's no reason to think Libya will be exempt. But gauging the problem is difficult, he says, because the region falls into “a real hole in terms of epidemiological data.”

    Colizzi and Massimo Amicosante, a biologist also at Tor Vergata, are here to start plugging that hole. They are meeting with Eteer to finalize an exchange program that will get Italian and Libyan disease researchers working together. The Italian government is an eager partner: It hopes for better disease prevention among the tens of thousands of sub-Saharan refugees each year who use Libya as the departure point on their way to Europe.

    Unruffled by Tripoli's fierce traffic, Eteer offers to take the Italian researchers—and Science—on a tour of the planned CIDCA site, beginning with a drive through the city's scrubby and desolate outskirts. After arriving, we slip through a gate in the barbed-wire-crested wall that surrounds the CIDCA compound and enter a different world. With the help of constantly running sprinklers, lush vegetation sprouts between the tennis courts, guesthouses, and other whitewashed buildings. Eteer hopes such amenities, all paid from the deep pockets of the Gaddafi Foundation, will help entice Western disease researchers to work here.

    In the main administration building, offices are filled with plastic-wrapped chairs and tables like gifts waiting to be opened. “I want the best scientists in the world to come work here, side by side with Libyans,” says Eteer, with a doctor's reassuring smile. Drawing comparisons with the Centers for Disease Control and Prevention (CDC) in Atlanta, Georgia, he envisions Tripoli as the focal point of a collaborative network. But at least initially, the scope of the Libyan institute will be narrower: It will focus on Africa's three big killers, namely AIDS, malaria, and tuberculosis.

    No mirage.

    Gaddafi appears as hero in his own “Epic of the desert,” a poster about a massive water project to supply coastal cities.

    CREDIT: J. BOHANNON/SCIENCE

    Although he does not expect the last bulldozer to leave the site until 2007, Eteer is already seeking a research director. Initially, he says, there will be room for 100 scientists doing a mixture of basic molecular research and epidemiology. To generate steady income, a diagnostic laboratory will handle all of Libya's blood samples, which are currently shipped abroad for testing, amounting to $10 million of potential income annually. There are also plans to build a factory on site to produce generic drugs for the three diseases. Competition for positions at CIDCA will be “open, like any Western institute,” but Eteer adds that the emphasis will be on building collaborations with Africans who “stand to gain the most” from Western expertise.

    “It is a grand plan, and badly needed,” says Bashir Allaghi, one of Gaddafi's personal physicians, who sits on the board of the Gaddafi Foundation. “We Libyans are open to the world. We are hungry for contact.”

    Outsiders seem optimistic but wary. The center could be a windfall for “the massive shortage of expertise in Africa,” says Kevin de Cock, director of CDC's Kenya field station. But without “very careful diplomacy,” he warns, it could also be a flop. One potential pitfall is its location. “Libya is far from sub-Saharan Africa, where these diseases are at their worst, so they will have to build satellite centers for fieldwork,” he says. And Gaddafi's pronouncements that Libya “speaks for Africa” have caused tension. De Cock is surprised to have heard about CIDCA only recently. “Are they going to collaborate or compete?” he wonders.

    Perhaps the biggest surprise is that “executive control” of CIDCA will be handed over to a Westerner. “I don't want a Libyan to be in charge,” says Eteer. “Only an outsider can be free from all the political pressures here.” Allaghi says the Gaddafi Foundation backs the plan. But one skeptic is Colizzi. “Will the Libyans really put a $100 million facility in Western hands? No way.” Another question is who would be willing to take up the post if Libya carries out the death sentence it imposed last year on a group of foreign medics. The opinions of many likely candidates, such as Hans Wigzell, director of medical research at the Karolinska Institute in Stockholm, Sweden, who calls the medics “Libya's scapegoats,” are already hardening.

    In spite of such doubts, Colizzi believes Libya's ambitions to bring modern medical science to Africa are genuine. “They do want to make this work,” he says. “The question is if they will really let science be independent of politics.”

    Prodigal son.

    Mustafa Eteer returned from Canada to help build Libya's disease research center.

    CREDIT: J. BOHANNON/SCIENCE

    Getting started

    CIDCA is a sign of things to come for Libya's academic community, according to Abdusalam Al-Gallali, Libya's new secretary of higher education. “We now have all the money we could need,” he says, “and our priority is to improve the quality of work and teaching.”

    Libya now claims to have set a high standard for the rest of the Arab world. Unusual for a Muslim nation, there appears to be gender equality in higher education: 50% of students are female, according to Al-Gallali, and the highest academic position—chancellor of El-Fateh University in Tripoli—is occupied by a woman. He also claims that Libya is second only to Canada in per capita attendance at university, where postsecondary education is estimated to be just over 50%.

    Libya hopes to employ these highly trained young people and keep them from emigrating, says Yusef Mabosut, a U.S.-trained microbiologist who was chancellor of El-Fateh until 2000. For some fields, such as geology and engineering, there seems to be endless room for growth. Beyond the oil industry, Gaddafi's $28 billion “Great Manmade River Project,” called the largest public works project in the world by the United Nations Educational, Scientific, and Cultural Organization, has employed thousands to pipe water from deep beneath the Sahara to Libya's coastal cities—and it's far from finished. But for students in other fields, the prospects look grim. This is one reason why the government is ramping up funding for new scientific projects such as CIDCA. Among others to benefit are the country's small community of astronomers; they are getting a new observatory.

    Last year Gaddafi personally contacted the French electronics company Sagem to buy a $13 million telescope, making up for a lost purchase from Germany that fell through during the embargo. Gaddafi is “passionate” about astronomy, says François Querci, an astrophysicist at the Observatoire Midi-Pyrénées in Toulouse, France. Plans call for the telescope to be set up in Libya's southeastern deserts, although abundant landmines—a legacy of war with neighboring Chad—could pose a problem. Querci was there in February to meet with the country's top astronomer, Hadi Gashut, to discuss Libyan participation in an embryonic network of observatories in Muslim countries. “Libya is taking a leadership role,” says Querci.

    With a 2-meter-diameter mirror, the Libyan telescope will be modest by world standards, but it will be perfect for studying variable stars that require continuous observation, says Michael Bode, an astrophysicist at Liverpool John Moores University in the United Kingdom. It will also be valuable, says Querci, as the only view from northern Africa, where the skies are far clearer than those over Europe along the same longitude. Observations are expected to begin in early 2006.

    Meanwhile, for Libyan archaeology the lifting of the embargo looks like a mixed blessing. The government, anticipating a boom in tourism, has renewed interest in researching and preserving the region's 10,000 years of human settlement. That should translate to more archaeology jobs, says Sa'ad Abdul Aziz, director of the Germa Museum in southern Libya, who coordinates archaeological research for Libya's Department of Antiquities. But at the same time, development of oil exploration, roads, and pipelines also may skyrocket. And particularly for the most vulnerable and least studied of Libya's archaeological heritage—such as the ancient rock engravings that can be found on boulders throughout the southern deserts—this spells trouble. With so much of Libya's income dependent on petroleum, it seems unlikely that archaeology will be given higher priority.

    But Aziz is optimistic. “We have been very isolated,” he says, “but that time is over. Everyone just wants to start the work.”

  10. SCIENCE IN LIBYA

    Evidence Overruled: Medics on Death Row

    1. John Bohannon*
    1. John Bohannon is a science writer based in Berlin.

    TripoliThe toll of the past few years shows on Zdravko Georgiev's ashen face. He was working as a doctor in southern Libya in 1999 when he heard that his wife Kristiyana—a nurse in the northern town of Benghazi and, like him, a Bulgarian—had been arrested. He rushed back to Benghazi and immediately contacted the police for information. After several days without word of his wife, he was arrested, too. And then, he says, the nightmare began: Torture without explanation, police interrogations, and accusations of conspiracy.

    After holding them for a year without access to lawyers or the outside world, prosecutors charged Georgiev, his wife, three other Bulgarian nurses, and a Palestinian doctor at the Benghazi hospital with acts of bioterrorism. The Libyan government accused the foreign medics of deliberately infecting children under their care with a strain of genetically engineered HIV. By then, hundreds of children at Benghazi's Al-Fateh hospital were found to have been mysteriously infected with HIV, and many had already died of AIDS-related illnesses. Today, the medics deny any wrongdoing, although they earlier gave confessions which they—and doctors who have been allowed to examine them—say were extracted under torture.

    Protests from abroad prompted Libya to invite European scientists to come to Benghazi and study the outbreak. The team, led by Vittorio Colizzi, a molecular pathologist at Tor Vergata University in Rome, and Luc Montagnier, a virologist at the Pasteur Institute in Paris and co-discoverer of HIV, concluded that the evidence was overwhelmingly in favor of the medics' innocence. They put the blame for the infections on negligent practices hospital-wide. But this opinion was rejected. To the shock of international observers, the Libyan court found the medics guilty last year and sentenced them to death by firing squad. Libya's Supreme Court will announce its verdict on the medics' final appeal on 31 May. Gaddafi has said he believes they are guilty.

    Western observers condemn the Libyan proceedings. “This was a betrayal to my profession,” fumes Hani Shennib, a Libya-born professor of surgery at McGill University in Montreal, Canada, who is coordinating relief efforts for the infected children.

    The timing could not be worse for Libya's efforts to shake its reputation as a lawless pariah state. The future of at least one major new Libyan science initiative—a disease research center near Tripoli—hangs on the outcome of this case (see main text). Outsiders see it as a test of whether Libya is truly ready to host such an institution. “Who would want to come work in a country where science and logic are not respected?” asks Hans Wigzell, director of medical research at the Karolinska Institute in Stockholm, Sweden. Wigzell was one of the authors of an open letter last year, signed by 28 scientists from eight countries, calling on Gaddafi to recognize the scientific evidence and intervene on the medics' behalf.

    End of the line.

    Six foreign medical workers in Libya have been sentenced to death on improbable charges of bioconspiracy; a final decision is pending.

    CREDIT: GEORGI MILKOV

    It seems as if “science itself has been on trial here, and lost,” says Colizzi, who was called as an expert witness by the Libyan court. Colizzi and Montagnier studied the outbreak in Benghazi between 2002 and 2003. “We were supposed to have free access to all the materials and data to make an objective study,” says Colizzi, “but in fact hospital officials tried to block us at every step.”

    The first surprise came when they asked to see the “smoking gun” in the case, a pair of vials allegedly found in the home of one of the Bulgarian nurses. In the court, a Libyan doctor presented the vials along with the results of a Western blot—a test using antibodies to detect the presence of a particular protein—which he said “proved” that the HIV outbreak originated from stocks kept secretly by the medics. Upon seeing the blot, Montagnier says, he concluded “it just looked like background noise.” He proposed to test the vials with the more sensitive polymerase chain reaction to look for specific RNA sequences of the virus. But officials never made the vials available.

    In spite of such hindrances, Colizzi and Montagnier were able to obtain blood samples and medical records from the children, examine the hospital, and interview its staff. It soon became apparent, says Colizzi, that “this is a classic nosocomial infection” in which tainted blood is accidentally passed between patients through poor hygiene practices, such as the reuse of disposable syringes and catheters, insufficient sterilization of instruments, and a general lack of quarantine between patients. The most compelling evidence of contamination they found, according to Colizzi, was the presence of other viruses in the children's blood, including several strains of hepatitis C. “This is extremely unusual for children,” says Colizzi, “but is easily explained if there have been multiple accidental contaminations in the hospital.”

    Colizzi and Montagnier maintain that these results alone should be enough to exonerate the accused, but Colizzi thinks another piece of evidence puts their innocence “beyond doubt.” According to the hospital medical records, some of the children became infected with HIV before the medics even started working at the hospital. And in one case, a child of HIV-negative parents became infected at birth in the hospital, long after the medics had been arrested. According to the prosecution, the dates are errors in the hospital's record keeping.

    The prosecutors have had some difficulty, however, sustaining the charge that the strain of HIV was engineered in a lab. “They jumped to this conclusion,” says Colizzi, “because this particular HIV strain did not appear in GenBank,” the database of genetic sequences maintained by the U.S. National Institutes of Health in Bethesda, Maryland. The Libyan government backed away from the claim in 2002, referring to the case as one of homicide rather than bioterrorism.

    In 2003, in the presence of international observers, including ambassadors from 13 countries, Colizzi and Montagnier presented their findings to the Libyan court. Five Libyan doctors at the same time accused the Europeans of being “unscientific” because of inconsistencies in some of the clinical data. Colizzi responds that the source of the data was the hospital itself, and that if the disputed data are removed, the case against the Bulgarians still doesn't hold up. But the Libyan judges were not persuaded: In May 2004, they declared the medics guilty. Georgiev alone was released with a suspended sentence, perhaps in light of the fact that he had not even been working at the hospital. He now lives within the protection of the Bulgarian embassy in Tripoli, where he met with Science.

    Since the sentencing, the Libyan government has said that the case might be “reconsidered” if compensation is paid—a sum of more than $5.7 billion was suggested—and if the British government is willing to release a Libyan accused of the 1988 bombing of a jet over Lockerbie, Scotland. “Scientific thinking has no more role to play in this anymore,” says Colizzi. “It's completely political now. Or perhaps it always was.”

  11. SCIENCE IN LIBYA

    Agencies Plan Exchange With Libya's Former Weaponeers

    1. Richard Stone

    U.S. officials are trying to involve Libya's weapons experts in outside collaborative projects. One potential hitch: The Libyans want to keep working on missiles

    After months of delicate planning, the United States is embarking on a groundbreaking effort to bring Libya's former weapons researchers in from the cold. The initiative is expected to include exchange programs to foster scientific and commercial cooperation between Western and Libyan scientists and a “sister” link between Lawrence Livermore National Laboratory in Livermore, California, and the Tajoura Nuclear Research Centre in Tripoli, Libya, which had been the nerve center of Libya's nuclear weapons program.

    “The steps being taken to engage the [former weapons] scientists are an important make-or-break element of Libya's reattachment to the international community,” says Rose Gottemoeller, an expert on nuclear nonproliferation at the Carnegie Endowment for International Peace in Washington, D.C. “If key elites such as the scientists” don't participate, she warns, “the danger of backsliding and failure becomes strong.” Building an esprit de corps with Libyan researchers could have a broader political payoff as well: It “can only be seen as a good deed in a time that most Muslim countries don't look too kindly on us,” says Jack Boureston, managing director of FirstWatch International, a nonproliferation think tank in Monterey, California.

    In contrast to the U.S. government's spotlighting of recent initiatives to find civilian work for former weaponeers in Iraq, few details about the Libya effort have been released. The U.S. State Department has asked U.S. officials and scientists in the U.S. national laboratories not to speak with the press about the Libya initiative; nonetheless, several agreed to speak with Science, but only on condition of anonymity. U.K. officials also involved in the effort declined to comment.

    Physical evidence.

    A U.S. guard in Oak Ridge, Tennessee, stands watch over contraband nuclear materials Libya surrendered last year.

    CREDIT: REUTERS/PAUL EFIRD/KNOXVILLE NEWS SENTINEL

    This caution, Science has learned, derives from a concern about ongoing, intricate negotiations with segments of Libya's former weapons community. Libyan officials apparently have asked that the evolving initiative not yet be publicized. “One particular concern” from the U.S. side, says a senior Bush Administration official, is that Libya's ballistic missile researchers “want to keep working on missiles. Obviously that's a problem,” he says. According to a nonproliferation official at the U.S. Department of Energy (DOE), the Libyan government claims to have 4000 missile scientists and technicians, including 500 with advanced degrees—the largest subset of former weaponeers being courted for exchanges.

    Libya's rapprochement with the West began after it announced on 19 December 2003 that it would disband its R&D on nonconventional weapons and eliminate existing stockpiles. Since then, investigators from the U.K. and U.S. governments and the International Atomic Energy Agency (IAEA) in Vienna, Austria, have assembled an increasingly detailed picture of the once-clandestine programs.

    Libya's nuclear R&D effort was more ambitious than suspected, but analysts believe it was at least several years away from a bomb. An IAEA report last year noted that in the 1980s uranium targets were irradiated in Tajoura's Soviet-made, 10-megawatt research reactor. Tiny quantities of plutonium were separated from at least two targets at a radiochemical laboratory, although investigators now believe that Libya focused solely on a uranium bomb. In March 2004, the IAEA report notes, about 13 kilograms of fissile uranium-235 were flown from Tajoura, on the eastern edge of Tripoli, to Russia for blending into power plant fuel. When it came clean in late 2003, Libya revealed a further 11 nuclear sites and 15 weapons-related sites.

    One particularly disturbing facet, experts say, is that Libya readily obtained materiel and know-how through a global nuclear black market, primarily the network run by the father of Pakistan's bomb, Abdul Qadeer Khan. “In our estimation there was not a lot of indigenous talent. [Libya] procured the equipment and bought the recipes,” says the Administration official. The IAEA report recounts how in late 2000 Libya had outfitted a pilot enrichment facility with three cascades of centrifuges based on an advanced design from Pakistan, before mothballing the equipment 2 years later for security reasons. In January 2004, a U.S.-U.K. team shipped 25,000 kilograms of Libya's most sensitive items, including centrifuge parts and uranium hexafluoride—the gas fed into centrifuges for concentration—as well as weapons designs to Oak Ridge, Tennessee, for analysis and destruction.

    According to Libya, 800 nuclear specialists, including 140 with advanced degrees, were involved in the program. “Right now we have no way to vet those numbers,” says the Administration official. U.S. officials note that some senior Libyan weaponeers were educated in Europe, particularly the United Kingdom, or in the United States before sanctions were imposed on Libya in the 1980s.

    Hot source.

    A research reactor at the Tajoura nuclear facility was used to make weapons-grade uranium.

    CREDIT: JOHN MOORE/ASSOCIATED PRESS

    Although Libya wasn't close to going nuclear, it produced chemical weapons and was accused by Chad of using mustard gas against its forces during a border conflict in 1987. (Libya has denied the allegation.) In March 2004, Libyan officials declared to international investigators that the country had stockpiled 23 tons of mustard gas at its al-Rabta facility, which Italy is now helping convert to a pharmaceutical plant. Libya says it has 120 former chemical weapons workers but just 12 with advanced degrees, according to the DOE official.

    “The Libyan nuclear and chemical scientific core is certainly smaller and less seasoned than that of other rogue regimes such as Iraq,” says Sammy Salama, a Middle East expert at the Monterey Institute's Center for Nonproliferation Studies in California. However, he says, their “relevant firsthand experience”—operating the Tajoura reactor and cooking up chemical weapons—“makes Libyan scientists desirable for other rogue regimes that may have WMD aspirations.”

    Libya's ballistic missile program, meanwhile, was centered on relatively primitive Scud designs. “Their missile work isn't thought to be all that great,” says a U.S. specialist. The Administration official insists that “carrots exist” to get researchers to abandon missile R&D; he declined to elaborate. Inspectors are still probing whether Libya had more than a passing interest in biological weapons.

    The U.S. State Department has taken the lead in organizing workshops between U.S. and U.K. experts and Libyan counterparts. The first two meetings, last October and December in Tripoli, explored potential collaborations on a hydrological and geochemical database, an environmental monitoring lab, technologies for water purification, and the production of medical radioisotopes.

    One initiative gaining traction is a sister lab agreement between Livermore and Tajoura. Although not finalized when Science went to press, the arrangement would resemble a successful DOE program for Russian nuclear scientists begun after the Soviet Union's dissolution in 1991. Joint research could include, for example, neutron activation analysis for materials science using Tajoura's research reactor and associated labs. DOE's National Nuclear Security Administration also aims to help convert the reactor from using highly enriched to low-enriched uranium fuel.

    In the meantime, U.S. officials are organizing a reciprocal visit later this spring of a Libyan delegation. The itinerary would include Livermore and Sandia National Laboratories and sites where Cold War-era nuclear weapons facilities have been dismantled—possibly Hanford in Washington state and Savannah River in South Carolina.

    Unlike the engagement effort in Iraq, U.S. officials expect oil-rich Libya to bring significant resources to the table. “They don't need our money; they need ideas,” says the Administration official. “Their main priority is partnership.” It's a fragile relationship that's just beginning to blossom.

  12. NATIONAL SCIENCE FOUNDATION

    Boom in Digital Collections Makes a Muddle of Management

    1. Elizabeth Pennisi

    Electronic collections are a huge boon to scientists. But a new report says NSF needs to pay more attention to how they are funded and operated

    Forget trays of preserved insects with their informational tags, as well as collections of rocks, fossils, and other samples from nature's treasure chest. Data have gone digital, and researchers from all walks of science—from climate modelers to systematists—are stockpiling their observations in newly created databases accessible to everyone through the World Wide Web. But as researchers head full speed into the digital world, the U.S. National Science Foundation (NSF) wants to ensure that they don't run out of gas along the digital highway and that the rules of the road are clear to everyone.

    To date, NSF has not been tracking its total commitment to the increasing number of digital data collections. Yet once started, these collections require continued—and likely increasing—support. At issue too are policing data to maintain standards of data quality, formatting data for eventual incorporation into metacollections, and presenting the information in ever-more-sophisticated, yet understandable, displays. More students and researchers need to know how to use the information, and database management should be recognized as a career on a par with lab research. The challenge for NSF and other agencies (see sidebar on p. 189) is how to satisfy all these needs without busting their budgets.

    Last week, NSF's oversight body, the National Science Board (NSB), approved a draft report that calls for a comprehensive plan to manage this increasingly important scientific asset (www.nsf.gov/nsb/meetings/2005/LLDDC_Comments.pdf). “The rate that the data are increasing is exponential,” says board member Michael Rossmann, a structural biologist at Purdue University in West Lafayette, Indiana. Adds Anita Jones, a computer scientist at the University of Virginia in Charlottesville and former board member, “I am concerned about the growing bill.” The board is eager for community input.

    Data boom.

    As with other data, molecular structures have gone from simple (middle) to complex (right) and require sophisticated storage technologies (left).

    CREDITS (LEFT TO RIGHT): COURTESY OF STORAGE TEK; B. DELABARRE, A. T. BRUNGER, J. MOL. BIOL. 347, 437 (2005)

    A growing concern

    Digital databases date back to the era of punch cards and computer tapes. In the 1970s, crystallographers agreed to deposit their data in the newly created Protein Data Bank (PDB) at Brookhaven National Laboratory in Upton, New York. The bank is now managed by the Research Collaboratory for Structural Bioinformatics located at Rutgers University in New Brunswick, New Jersey, and the University of California, San Diego. Each week a staff of 25 adds 100 new molecular structures to the 30,000 already deposited. About 10,000 individuals visit the database daily, says its head Helen Berman, who calls PDB “the center of the new biology.”

    Such a growing enterprise requires continued funding. PDB's annual budget has grown 200-fold since 1976, to about $6 million. Some $2 million comes from NSF, and eight other organizations chip in the rest. “It's money well spent,” says NSB Chair Warren Washington. “We cannot afford to have these data sets lost or poorly handled.”

    A climate modeler at the National Center for Atmospheric Research (NCAR) in Boulder, Colorado, Washington knows how valuable long-term data sets can be for simulations and other research efforts. NSF provides about two-thirds of NCAR's $139 million annual budget, but NSF's contribution to its dozens of databases is harder to quantify, says Richard Anthes, president of the University Corporation for Atmospheric Research, which oversees NCAR. “It is on the order of about $10 million,” he estimates.

    NCAR databases contain an estimated 1.6 petabytes of oceanographic, climate, and other information. The size of its Scientific Computing Division data-support section doubled last year, says its manager Steve Worley, who adds, “I imagine that's happening for almost everybody. I don't see any end.” As with other databases, new entries need to be formatted and incorporated into the existing databases, which are updated regularly to take advantage of the latest storage technology.

    These two projects illustrate the growing importance—and expense—of keeping data accessible, possibly in perpetuity, to all who want to use them. NSF doesn't have a good handle on its portfolio, says NSB executive officer Michael Crosby, who guesses that the agency could be supporting “hundreds, even thousands,” of digital data collections. They range from those built to suit an individual researcher's needs to ones that are essential to many disciplines. The mode of funding is equally haphazard, says NSB member and ecologist Daniel Simberloff of the University of Tennessee, Knoxville. “What we are asking NSF to do is come up with a single strategy” for evaluating and prioritizing these projects, he says. Part of that strategy should include criteria to determine continued support. There should also be guidelines about the right balance between data maintained and the acquisition of new data, says Rossmann.

    Projects such as PDB and the NCAR collection illustrate how a decision years ago to support a database can have significant, long-term implications for NSF's budget. “Clearly the current trend is to spend a large proportion [of NSF's database support] on maintaining databases,” says Rossmann. When times are tight, however, that emphasis could mean fewer research awards.

    Avoiding obsolescence.

    To be useful, digital databases require constant improvements to data storage, quality, and accessibility.

    CREDIT: PDB

    Data-rich but poor

    That doesn't mean database managers are feeling flush, however. “We have money troubles all the time,” NCAR's Worley says, citing his desire to incorporate data from different collections into a single, seamless data resource. But that goal has taken a back seat to maintaining what's already on hand. Likewise, a compendium of Arabidopsis data at the Carnegie Institution Department of Plant Biology in Stanford, California, and the National Center for Genome Resources in Santa Fe, New Mexico, recently received about $3 million less from NSF than the almost $11 million its managers had requested for the next 5 years. “We ended up having to give up a lot of innovative stuff,” says Arabidopsis Information Resource lead investigator Seung Yon Rhee, a Carnegie plant biologist.

    One solution to funding shortfalls is to find other backers. Both NCAR and PDB supplement NSF's contribution with money from other federal agencies and international organizations. In other cases, host institutions are expected to cover costs for maintenance and upkeep. That's been the approach taken by NSF's Biological Research Collections program, which has helped keep natural history specimens in good shape but which now limits awards to one-time support of specific goals and projects.

    To make NSF's money go further, biological research collections program manager Mark Farmer spends about half of his $4.5 million budget on a new long-term digital data collection—a “virtual” natural history museum with a portal that will provide desktop access to the world's preserved plants, animals, rocks, and so on. At the same time, museums and universities have agreed to bear the cost of operations for their collections, including keeping the links current and the original specimens in good shape. “We don't want to get into the business of paying for permanent staff at an institution,” says Farmer.

    The science board's goal, says Simberloff, is “to make sure that the data collections we are funding are of the highest quality, that standards for storage and access are good.” Toward that end, its report asks NSF to tally up all databases under its wing and to establish consistent rules to evaluate and fund them. That may include clarifying who is in charge of policing the data and requiring a database management plan covering the kind of data to be included, the standards for quality, and the criteria for what will be archived.

    Key human resources issues also need to be addressed, says NSF program director Chris Greer. One big issue is encouraging database managers to develop new ways to disseminate the information more broadly. Greer cites the PDB's “Molecule of the Month,” which provides online images and lay-language summaries of a protein's structure, function, and relevance to human health, as an excellent example of outreach to students.

    A second issue is preparing undergraduates, graduate students, and postdoctoral fellows to take advantage of all these databases. NSF's 2006 budget request, now pending, includes a new program to expand competence in computing and other skills needed by 21st century scientists. Greer says that even more focused training programs may be needed.

    Finally, Greer and others say that those who maintain these databases should be recognized as credible scientists whose work warrants tenure and other career advancements. “They are collectively an outstanding resource,” Greer says. Toward that end, PDB's Berman says she encourages her employees to write research papers and speak at conferences and offers opportunities for career advancement. “It's very important to keep them motivated,” she points out.

    The science board's report sends NSF a signal that there's work to be done. “The NSF strategy and policies have not kept pace” with what's needed, the report points out. But Berman is optimistic that NSF will catch up. “The best thing is that NSF is now prepared to think about this.”

  13. NATIONAL SCIENCE FOUNDATION

    Canadian Report Calls for Data Agency

    1. Wayne Kondro*
    1. Wayne Kondro is a freelance writer in Ottawa.

    OTTAWA—Canada needs an agency dedicated to ensuring maximum access to the fruits of publicly funded research.

    That's the conclusion of a task force formed by a bevy of scientific organizations, which last week urged government officials to create a national data preservation and management organization. Such an agency would craft a national strategy relating to the acquisition, maintenance, and dissemination of all types of research data, from published scientific material to electronic archives and databases. A blue-ribbon panel chaired by David Strong, president of the private University Canada West in Victoria, British Columbia, suggested that the Canada Foundation for Innovation, which helped back the 9-month study, take the first step by providing start-up money.

    The initial questions to be examined include many of those addressed in a draft report from the oversight body of the U.S. National Science Foundation, such as standardization of format, training, and funding for databases (see main text). Proponents hope that federal legislators will create a statutory agency—called Data Canada—with a $2.5-million-a-year budget to investigate a “central data preservation and management facility and a series of access and service nodes located in research institutions” across the country. The panel didn't speculate on how much it would cost to create and operate such a system.

  14. AMERICAN PHYSICAL SOCIETY MEETING

    Signs of a Second Flowing Solid Deepen a Quantum Mystery

    1. Adrian Cho

    LOS ANGELES, CALIFORNIA—From 21 to 24 March, more than 6500 gathered to ponder flowing solids, splashless droplets, and living crystals.

    If two's a trend, then bizarre flowing solids are la mode. In the past year, experimenter Moses Chan and colleagues at Pennsylvania State University, University Park, have reported that, at high pressures and temperatures approaching absolute zero, solid helium appears to flow like a liquid without any viscosity. Now, as theorists debate how such “superflow” is possible in a crystal, Chan and Penn State's Anthony Clark report that solid hydrogen seems to behave in the same strange way.

    The preliminary hydrogen data met with skepticism from some researchers. “The temperature they're seeing [the onset of flow] at is right at the temperature they see it for helium,” notes James Day, a physicist at the University of Alberta in Edmonton, Canada, and that coincidence could point to some undiscovered experimental artifact. “I think it's a little suspicious,” Day says. But others argue that in key regards, hydrogen is similar to the helium isotope used in the earlier experiments, helium-4. “If it's seen in one, it should be seen in the other,” says Milton Cole, a theorist at Penn State.

    Researchers presented several theories to explain the helium results, but none of them accounts for every experimental detail. On one point everyone agrees: If the solid really does flow, “supersolid” helium would rank among the most important discoveries in low-temperature helium physics, a field that has already nabbed four Nobel prizes. “I expect it to get the Nobel,” Cole says, “if it's right.”

    Twisted.

    Within this oscillating can, solid helium appears to flow with no resistance.

    CREDIT: JOHN PASSANEAU/PENNSYLVANIA STATE UNIVERSITY

    Since 1937, physicists have known that at temperatures below 2.17 K, liquid helium-4 can flow without resistance. That happens because many helium atoms collapse into a single quantum wave that resists disturbances. For decades theorists have speculated that a similar thing might happen in solid helium-4, too. The original idea was that missing atoms, or vacancies, within a helium crystal could team up to form a free-flowing fluid of their own, so that the superflow of missing atoms in the solid would mimic the superflow of real atoms in the liquid. But experimenters had not been able to produce the elusive supersolid.

    To spot it, Chan and Eunseong Kim employed a torsional oscillator—essentially a little can of helium rotating back and forth on the end of a thin shaft. The can oscillates at a frequency determined by the stiffness of the shaft and the can's inertia, which in turn is determined by the mass of helium stuck to it. Chan and Kim pressurized the helium to between 25 and 145 times atmospheric pressure to ensure that it solidified. At each pressure, the frequency of oscillation climbed suddenly as the temperature dipped below 2 tenths of a kelvin. Those upswings suggest that some of the helium lets go of the oscillator and slips through the crystal without any resistance.

    But just how that's possible remains a subject of controversy. Vacancies probably cannot account for the data, Chan explains, because if they are so mobile, they ought to wander to the edges of the crystal and blink out of existence. On the other hand, computer simulations by theorist Bryan Clark of the University of Illinois, Urbana-Champaign, indicate that in a flawless crystal of helium-4, the atoms cannot collapse into a single quantum state.

    Boris Svistunov and colleagues at the University of Massachusetts, Amherst, theorize that solid helium consists of many small crystalline grains and that superflow occurs along the boundaries between them. But experimenters have evidence that helium forms large grains that would provide too little interfacial area to account for the observed flow.

    Ultimately, physicists will have to rethink the concept of a crystal, says Wayne Saslow, a theorist at Texas A&M University in College Station. Ordinarily, atoms in a crystal stack into rows like billiard balls. But, thanks to quantum mechanics, light and lively helium atoms behave like extended waves that somehow overlap to create the corrugated crystal structure, Saslow says, and theorists must decipher how such a quantum solid works: “We don't know what a solid is. We only thought we knew.”

  15. AMERICAN PHYSICAL SOCIETY MEETING

    In a Vacuum, No One Sees You Splatter

    1. Adrian Cho

    LOS ANGELES, CALIFORNIA—From 21 to 24 March, more than 6500 gathered to ponder flowing solids, splashless droplets, and living crystals.

    Nature may abhor a vacuum, but a vacuum abhors a mess. In the absence of air, a droplet of liquid can crash into a smooth surface without splattering, report physicists Lei Xu, Sidney Nagel, and colleagues at the University of Chicago, Illinois.

    “I was very surprised to see [the splash] go away and this beautiful smooth spreading of the droplet emerge as the air pressure was reduced,” says Mark Robbins, a theorist at Johns Hopkins University in Baltimore, Maryland. Robbins says he would have assumed that the splashing depended on the properties of the liquid alone.

    The splash spits out a ring of smaller droplets, and Xu and Nagel were studying their sizes and speeds when they discovered that pumping away the surrounding air eliminated the splash altogether. Within a tall vacuum chamber, the researchers released droplets of alcohol from various heights onto a dry glass plate. They recorded the resulting splashes with a high-speed video camera as they varied the pressure in their apparatus, sucking it down as low as 1% of atmospheric pressure. The droplets struck the surface with speeds ranging from 2 to 7 meters per second, and for a given speed, the researchers found they could suppress the splash by lowering the pressure below a specific threshold.

    Now you see it.

    A droplet in air (left) makes a splash; one in a vacuum spreads smoothly.

    CREDIT: LEI XU/UNIVERSITY OF CHICAGO

    The researchers explain the results with a simple theory. As a drop strikes the surface, liquid spreads sideways at supersonic speed, creating a shock wave. The shock wave pushes back on the liquid, and if that force is greater than the internal forces holding the liquid film together, the shock wave lifts it off the surface and creates a splash. Reducing the pressure reduces the force the shock wave exerts.

    Ironically, the theory predicts that a thicker liquid should splash more easily than a thinner one. The researchers tested this prediction by dropping three types of alcohol with different viscosities. As predicted, the more viscous the alcohol, the lower the pressure needed to prevent splashing, the researchers reported. They also confirmed that a weighty gas such as krypton produced splashes at lower pressure than a lighter gas such as helium did.

    “It's just the sort of thing all physicists should do,” says Walter Goldburg, an experimenter at the University of Pittsburgh, Pennsylvania. “They spotted a nonintuitive phenomenon and pursued it” to a complete understanding. Xu and Nagel speculate that the odd phenomenon could make a splash with technologists, as it might be used to control splatter in industrial processes such as spray coating and inkjet printing.

  16. AMERICAN PHYSICAL SOCIETY MEETING

    Recipe for Flies' Eyes: Crystallize

    1. Adrian Cho

    LOS ANGELES, CALIFORNIA—From 21 to 24 March, more than 6500 gathered to ponder flowing solids, splashless droplets, and living crystals.

    The striking hexagonal pattern in a fly's compound eye forms in the same way that a crystal grows, say physicists who have modeled the chemical interactions driving the process. The layered pattern of atoms in a crystal emerges as additional atoms nestle into the dimples between those in the previous layer. In the same way, the pattern in the larval fruit fly's eye emerges as each new eyelet, or ommatidium, fits into a gap in the previous row of elements, reports David Lubensky of the Free University of Amsterdam in the Netherlands. The step-by-step process produces the delicate pattern without a detailed blueprint.

    The results support the notion that short-range signaling determines structure, says Albrecht Ott, a physicist at the University of Bayreuth in Germany. “Short-range communication is just so easy,” Ott says. But researchers agree that the model must be tested experimentally.

    The mechanism may be another tool with which nature sculpts living forms. The basic structure of the fruit fly's body is determined by gradients in the concentrations of proteins in the embryo. The gradients tell each cell where it is and what genes it should express. But that mapping scheme does not account for the eye pattern, says Boris Shraiman of the University of California, Santa Barbara. With hundreds of ommatidia, the eye has too many parts for such a mechanism, he says, and the genes involved do not produce static protein gradients.

    Row by row.

    A fly's eye grows the way a crystal does, according to a chemical model.

    CREDIT: STONE/GETTY IMAGES

    So Lubensky and Shraiman tried to create the pattern another way. In 1952, British mathematician Alan Turing proposed that patterns form within a developing organism when a pair of chemicals, an “activator” and an “inhibitor,” diffuse into each other and engage in a tango that leads to regions alternately rich in each chemical. The different regions then trigger different types of growth. The Turing mechanism appears to explain zebra stripes and other pigment patterns, but Lubensky and Shraiman couldn't make it produce the pattern in the fly's eye.

    Instead, they found that each budding ommatidium simply nestles itself into the space provided by its neighbors. The transcription factor atonal controls the process. A wave of atonal expression moves across the undifferentiated eye disk, leaving behind spatially separated individual cells expressing atonal, which seed the ommatidia. Interactions between atonal and diffusing proteins such as scabrous that inhibit it determine which cells continue to express atonal, Lubensky and Shraiman report. Using experimentally determined relations between atonal and such inhibiting factors, they modeled the process and found that, instead of producing a specific pattern with a definite spacing—as the Turing mechanism would do—the interactions merely ensured that each row of ommatidia patterned itself after the previous one.

    Now researchers are looking for ways to test Lubensky and Shraiman's model. For example, the model predicts that disrupting signaling between emerging rows of ommatidia even temporarily should cause the pattern to change dramatically across the rest of the eye—something that would not happen if the Turing mechanism were at work, says Herbert Levine, a theorist at the University of California, San Diego. Nicholas Baker, a molecular biologist at the Albert Einstein College of Medicine in New York City, has collected preliminary data that support the conjecture, Lubensky said at the meeting.

  17. AMERICAN PHYSICAL SOCIETY MEETING

    Snapshots From the Meeting

    1. Adrian Cho

    LOS ANGELES, CALIFORNIA—From 21 to 24 March, more than 6500 gathered to ponder flowing solids, splashless droplets, and living crystals.

    Broadcasting with nantennae. Individual polymer molecules can stand on end and radiate light in exactly the same pattern that radio towers pump out radio waves, reports Michael Barnes, a chemist at the University of Massachusetts, Amherst. When excited with laser light, each fluorescent molecule pumps out photons in a “dipole” distribution, just as an antenna broadcasts radio waves. Within so-called nanophotonic devices, the “nantennae” might be lined up in “phased arrays” that would allow them to radiate in concert and direct their light in specific directions, Barnes says.

    Energy: The stuff of confusion. Nearly half of college students come away from introductory physics classes thinking energy is a material substance, reports Michael Loverude, a physicist at California State University, Fullerton. Studying quiz and exam answers from classes for nonmajors, Loverude found that many students believe, for example, that a battery grows noticeably lighter as it runs down, implying that energy is a weighty thing. Andrew Boudreaux, a physicist at Western Washington University in Bellingham, notes that even physicists talk as if energy were a substance. “If you tried not to,” he says, “you'd be talking in a very abstruse way.”

    Play your favorite proteins. Soon, identifying proteins may be as simple as slapping a compact disk into a specialized CD player, reports David Nolte and colleagues at Purdue University in West Lafayette, Indiana. The researchers have developed BioCD, a compact disk covered with gold spokes plated with various molecular targets. When molecules bind to spokes adorned with a particular target, they alter laser light reflecting off the disk. The technology should be more quantitative and faster than fluorescence bioassays, Nolte says, and could potentially assay 10,000 proteins at once.

  18. LUNAR AND PLANETARY SCIENCE CONFERENCE MEETING

    Ski Mars, While There's Still Time

    1. Richard A. Kerr

    LEAGUE CITY, TEXAS—Scientists met here from 14 to 18 March to focus on the ever-popular Mars and new data returned from the Saturn system by Cassini-Huygens.

    The Mars rovers picked up plenty of signs of long-ago water, but except for the ice of polar regions, reports of actual martian water—water ice under even tropical conditions—have been scarce. Now, however, with torrents of new imaging as well as new search strategies, researchers are seeing striking evidence of full-blown glaciers, some of them near the martian equator. Although they're not likely to be flowing today, many of these now-buried glaciers probably still contain ice laid down during the last great ice age of Mars more than 5 million years ago.

    The key to the renaissance in martian glaciology is “new data seen with new eyes,” says planetary geologist James Head of Brown University in Providence, Rhode Island. The new data have come from instruments aboard the Mars Global Surveyor and the camera on Mars Express.

    The new eyes came from realizing that martian glaciers wouldn't look like most glaciers on Earth. Unlike most terrestrial glaciers, which slip along a wet layer at their base and bulldoze everything in their path, the far colder martian glaciers would ooze ever so slowly over the landscape rather than through it. Head and glaciologist David Marchant of Boston University in Massachusetts have found glaciers like that in Antarctica's deeply frigid Dry Valleys. “When you're down there, you feel you're on Mars every day,” says Head.

    The hourglass.

    A glacier appears to have descended from this 4-kilometer-high mountain (height exaggerated by 30x).

    CREDIT: DLR/HRSC/ESA

    The features researchers are seeing on Mars are “just dead ringers for what we see in the Antarctic Dry Valleys,” says Head. He and Mars Express colleagues reported at the meeting that they recognize glacial flows off high massifs east of the Hellas Basin at 40° south and at the base of lofty Olympus Mons at 18° north. Head and his Brown University colleagues showed a large depression at 39° north whose ridged floor appears to be converging on a gap in its southern rim and flowing out. And Ernst Hauber of the German Aerospace Center in Berlin and Mars Express camera team members showed that glacial deposits fill a volcanic crater on the side of Hecates Tholus at 30° north. The list of glacial presentations goes on.

    “I'm pretty impressed,” says Mars geologist Michael Carr, emeritus researcher at the U.S. Geological Survey in Menlo Park, California. Ice does seem to have flowed across parts of Mars, he says. Glaciers aren't forming there today, most researchers agree, because the current climate locks up too much water at the poles. But to judge by the scarcity of impact craters, these glaciers were flowing in the geologically recent past—say, millions to tens of millions of years ago. Back then, calculations show, Mars was tilted much farther on its side, which would have allowed the sun to warm the poles and drive some of their water toward the equator.

    Some of that ice is probably still where it stopped flowing when the climate changed, researchers say. They don't usually see the pits and crevasses that would mark the loss of underlying ice back to the atmosphere by sublimation. Apparently, surface layers of rock and dirt have insulated the ice and preserved it for millions of years, as similar debris has done on Dry Valley glaciers. When Mars Express deploys the antennas of its ground-penetrating radar in early May, researchers may get to the bottom of the glaciers of Mars.

  19. LUNAR AND PLANETARY SCIENCE CONFERENCE MEETING

    Rovers, Dust, and a Not-So-Wet Mars

    1. Richard A. Kerr

    LEAGUE CITY, TEXAS—Scientists met here from 14 to 18 March to focus on the ever-popular Mars and new data returned from the Saturn system by Cassini-Huygens.

    The Red Planet could just as easily be called the Dust Planet. Dust is pretty much everywhere on Mars. It gives the planet its color (actually more of a yellowish brown than red), and it coats almost everything it doesn't bury. Most scientists had assumed that Mars's dust was the end product of some sort of planetary rusting, but researchers examining dust captured by magnets on the Mars rovers have found that dust's magnetic component is mainly pristine magnetite, the shiny-black mineral of lodestones. Despite all the talk about how wet Mars has been, even tiny bits of its rock have escaped eons of weathering unscathed. That supports an emerging picture of a Mars wet mainly in its early days—and then only wet intermittently.

    The dust discovery comes from the Magnetic Properties Experiments (MPE), a set of variously shaped magnets of differing strengths mounted on the Opportunity and Spirit rovers. Morten Bo Madsen of the University of Copenhagen, Denmark, and his MPE teammates reported at the meeting that the way atmospheric dust has accumulated on the magnets means that nearly all of the dust particles must contain at least a trace of a strongly magnetic mineral, which two of the rovers' arm-mounted analytical instruments identified as magnetite.

    Magnetite had not been the leading contender for martian magnetic dust. Yellowish brown maghemite, another iron oxide, was presumed to be the magnetic component after the Viking and Pathfinder missions. It had the right color, fit the reported oxidizing condition of martian soil, and could have formed in hot springs or by water weathering of exposed rock. Magnetite, on the other hand, must be unchanged from the day it crystallizes from molten rock.

    Finding magnetite apparently eroded unaltered from the rock is consistent with other recent findings on Mars. Geologist Matthew Golombek of the Jet Propulsion Laboratory in Pasadena, California, and rover teammates reported at the meeting that about 10 centimeters of the 3-billion-year-old floor of Gusev Crater where Spirit landed has eroded away, presumably by the wind. Water-dominated erosion on Earth, even when it's slow, is 50,000 times faster than that, Golombek noted. That implies that on Mars, “a dry and desiccating environment similar to today's” has been active for about 3.7 billion years.

    Several presentations at the meeting considered how the expanse of salt deposits Opportunity discovered could have come about if only scant amounts of acidic water were available to erode rock on early Mars. The much discussed “shallow seas” of early Mars now more often appear as intermittent puddles among normally dry dunes. The Dust Planet may have been dusty for a long, long time.

  20. LUNAR AND PLANETARY SCIENCE CONFERENCE MEETING

    Icy Volcanism Has Rejuvenated Titan

    1. Richard A. Kerr

    LEAGUE CITY, TEXAS—Scientists met here from 14 to 18 March to focus on the ever-popular Mars and new data returned from the Saturn system by Cassini-Huygens.

    With a surface temperature of 179°C below zero and having had more than 4 billion years for its inner fires to damp, Saturn's icy moon Titan might seem an unlikely place to find lively geology. But the Cassini spacecraft returned promising images when it passed by the moon late last year and again in February. After further analysis, Cassini team members at the meeting could confidently point to “ice lava” flows, a huge volcanic ice dome, and possible ice volcanic calderas. Titan does seem able to resurface itself volcanically, which would help explain its surprisingly youthful appearance. Now planetary physicists just have to figure out how Titan still does it after all these years.

    Two of Cassini's instruments pierced Titan's obscuring haze to return detailed images of cryovolcanic features. The Cassini radar produced images by bouncing microwaves off long strips of terrain. Rosaly Lopes of the Jet Propulsion Laboratory in Pasadena, California, and her radar teammates found a 180-kilometer-wide, flat-topped dome, Ganesha Macula, which bears a striking resemblance to the rocky volcanic domes of fiery-hot Venus. Ganesha Macula has a calderalike central depression, a radar-bright, flowlike feature spreading from center to edge, and four apparent channels meandering outward. One of them runs for more than 90 kilometers and may debouche near the dome edge as an icy lobate flow. And elsewhere in the radar strip, apparent flows extend as far as 200 kilometers, in two cases emanating from presumed volcanic craters.

    Icy eruptions.

    Radar revealed 180-kilometer-wide Ganesha Macula, a broad dome strewn with “lava” flows.

    CREDIT: LOPES ET AL./JPL/NASA

    At haze-piercing near-infrared wavelengths, the Visual and Infrared Mapping Spectrometer (VIMS) returned relatively high-resolution images of a few small parts of Titan, one of which contains a so-far-unique spiraling feature dubbed “the Snail.” Thirty kilometers wide, it sports a central dot that's dark to radar and therefore presumably smooth. Sébastien Rodriguez of the University of Nantes, France, and VIMS teammates take the Snail to be a possible volcanic dome with a central caldera.

    So cryovolcanic eruptions have probably resurfaced at least some parts of Titan. That's not completely unexpected. Unlike Saturn's Enceladus (Science, 4 March, p. 1387), Titan has plenty of rock deep within it that is still generating substantial heat from radioactive decay. Its ice could melt tens or hundreds of kilometers down, says planetary physicist David Stevenson of the California Institute of Technology in Pasadena. And ammonia thought to be within the moon could lower the melting point of ice, allowing water-ammonia lavas to flow on the surface, much as molten-rock lavas flow on Earth.

    But Stevenson does wonder how Titan could still be flooding its surface with cryolavas this late in its life. No impact craters have been seen on any cryovolcanic features, implying that they are relatively young. Yet, notes Stevenson, billions of years of volcanic activity would have extracted the interior's reservoir of ammonia. Without that antifreeze, cryolavas could not flow. If cryovolcanism has indeed been geologically recent, Titan must be somehow recycling its ammonia back into the interior, he says.

  21. LUNAR AND PLANETARY SCIENCE CONFERENCE MEETING

    Snapshots From the Meeting

    1. Richard A. Kerr

    LEAGUE CITY, TEXAS—Scientists met here from 14 to 18 March to focus on the ever-popular Mars and new data returned from the Saturn system by Cassini-Huygens.

    Genesis reborn. After the Genesis spacecraft smashed into the Utah desert floor last September, team members hoped to recover at least some of the solar wind particles the craft had collected in deep space. At the meeting, the mission's first solid results bore out that optimism. “We see solar wind” in Genesis collectors, said team member Daniel Reisenfeld of the University of Montana, Missoula, “and we can measure it quantitatively and accurately.” It won't be easy, though. The 10,000 separate pieces of shattered collection surface are covered with billions of micrometer-size bits of desert dirt. There's even a “brown stain” of goo vaporized from the spacecraft and deposited on some of the collectors while in space. Still, said principal investigator Donald Burnett of the California Institute of Technology in Pasadena, “we're not giving up on anything we wanted to do before the crash.”

    Meteorite launcher?

    An impact on Syrtis Major of Mars may have blasted rock to Earth.

    CREDIT: THEMIS/U. OF ARIZONA/NASA

    A younger Mars? Meteoriticist Ralph Harvey wants to redefine planetary old age. At the meeting, Harvey, who works at Case Western Reserve University in Cleveland, Ohio, and spectroscopist Victoria Hamilton of the University of Hawaii, Honolulu, concluded from spectroscopic data that the sprawling Syrtis Major volcanic center on Mars has the same distinctive iron- and magnesium-rich composition as the Nakhla/Chassigny group of eight known martian meteorites recovered on Earth. Syrtis Major might be the elusive source of these martian rocks, they said. They even point to a crater from an impact that could have launched Syrtis Major rock toward Earth. But the martian meteorites congealed from lavas 1.3 billion years ago, whereas counting the impact craters accumulated on Syrtis Major gives an age of 3.3 billion years for its rock. If the martian meteorites in fact came from Syrtis Major, Harvey and Hamilton note, crater counters have overestimated all martian surface ages by a factor of 2 to 3. A younger Mars would mean, among other things, that the planet was wet through most of its history rather than just in its earliest days.

    Spirit rover rejuvenated. Life was hard for the Spirit Mars rover early last month. So much dust had settled on its solar panels that the intrepid explorer was down to less than half its original power supply—not far from the “death zone,” said rover team leader Steven Squyres of Cornell University in Ithaca, New York. Then came the miracle. From one Mars day to the next, Spirit's power bounced back to 90%. The rover's panoramic camera showed panels so clean they looked like the rover was “just off the showroom floor,” quipped one team member. Opportunity, Spirit's twin on the other side of the planet, had enjoyed similarly mysterious solar panel cleanings. Spirit, Squyres reported, may have been swept clean by blustery winds while perched on a high ridge in the Columbia Hills.

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