Small, Rocky Planets Are Most Likely to Survive the Death of a Star

by Ryan Whitwam

Stars are not forever, although they have lifetimes measured in millions of billions of years. When they finally reach the end of their life, most of the planets that have called a solar system home will be blasted to pieces or ejected into deep space. New research from the University of Warwick points out that some planets may survive and have a greater impact on the solar remnant that remains.

When a “main sequence” star like the sun gets on in years, it exhausts its hydrogen fuel. It will be able to keep up the fusion reaction by creating heavier elements, but eventually, it swells into a red giant. During this phase, many of the planets in a solar system are consumed or pushed out into space. Later, the star blasts off its outer layers and becomes a white dwarf. Larger stars end up as neutron stars, and very large ones can become black holes.

The University of Warwick analysis focused on stars like the sun that will become white dwarfs. The team developed a computer model to simulate what happens to a solid, nearly spherical planet as it experiences the intense tidal forces of a star’s death throes. The team determined that larger solid worlds are more likely to crumble under the pressure and that less monolithic balls of ice and rock will break apart…