PerspectivePlanetary Science

A glance into the end of a planetary system

See allHide authors and affiliations

Science  05 Apr 2019:
Vol. 364, Issue 6435, pp. 25-26
DOI: 10.1126/science.aax0051

You are currently viewing the summary.

View Full Text

Log in to view the full text

Log in through your institution

Log in through your institution

Summary

A white dwarf is the remnant core of a star, with an initial mass smaller than eight times that of the Sun, compressed into a volume comparable to that of Earth. The vast majority of stars known to host planets will eventually end up as white dwarfs. After a phase of expansion, a white dwarf loses its outer envelope to space, thereby shattering any planets that are orbiting closely around it. On page 66 of this issue, Manser et al. (1) report the detection of a small solid body (planetesimal) orbiting a white dwarf with a period of 123.4 min. This discovery was made by using ground-based optical spectroscopy and an approach that is different from how planets orbiting stars other than the Sun (exoplanets) are commonly found. The method should enable characterization of the very last stages of the evolution of a planetary system as well as the composition of planetary cores (2).

View Full Text

Stay Connected to Science