Could Earth survive the Sun’s demise?

David L. Chandler in New Scientist:

Dn79721_250Solar systems may continue to exist around stars that have reached the end of their lifetimes, flared up and collapsed. New evidence shows that asteroids and dust discs, and perhaps even planets, may circle white dwarf stars, the burned-out remnants of stars that have already undergone their all-consuming red-giant phase.

This suggests that, for our solar system too, there is a possibility of life after the presumed death of the inner planets – when the Sun expands to such a bloated size that it envelops the orbit of the Earth and beyond. But it may be a grinding sort of life.

The new findings, to be published in the Astrophysical Journal, are based on high-resolution spectroscopic imaging of the white dwarf GD 362, made with the Gemini North, IRTF and Magellan telescopes on Mauna Kea, Hawaii. These observations showed an unexpected excess of infrared in the light of the star, as well as a huge abundance of calcium – the second-highest ever seen from a white dwarf.

More here.