Research Article

Samples of Stars Beyond the Solar System: Silicate Grains in Interplanetary Dust

See allHide authors and affiliations

Science  04 Apr 2003:
Vol. 300, Issue 5616, pp. 105-108
DOI: 10.1126/science.1080576

You are currently viewing the abstract.

View Full Text


We have identified six circumstellar silicate grains within interplanetary dust particles (IDPs). Their extrasolar origins are demonstrated by their extremely anomalous oxygen isotopic compositions. Three 17O-rich grains appear to originate from red giant or asymptotic giant branch stars. One 16O-rich grain may be from a metal-poor star. Two 16O-poor grains have unknown stellar sources. One of the grains is forsterite, and two are amorphous silicate “GEMS” (glass with embedded metal and sulfides), which is consistent with astronomical identifications of crystalline and amorphous silicates in the outflows of evolved stars. These observations suggest cometary origins of these IDPs and underscore the perplexing absence of silicates among circumstellar dust grains from meteorites.

View Full Text