Planetary radii and orbital periods for planets (black circles) and planetary candidates (red circles) discovered by the Kepler mission. The dashed curves shows how close different planets can get to their host stars before they would be tidally disrupted. Taken from Jackson et al. (2016).
Exciting news – just today, my research group had another paper accepted for publication, so we’ve added one more tiny brick to the edifice of human knowledge.
This paper explored tidal disruption of gaseous exoplanets. Over the last few decades, astronomers have discovered thousands of planets outside of our solar system, so-called “exoplanets”.
Most of the planets do not resemble planets in our solar system, and owing to biases in the way we find the planets, many of them are big, gas balls like Jupiter but orbiting much closer to their host stars than planets in our solar system – these planets are called “hot Jupiters“. The figure at left shows how close some of these planets are to their host stars.
Many of these hot Jupiters are doomed to spiral in toward their host stars, and when they get too close, the star’s gravity can rip them apart in a process called “tidal disruption“.
In our recent paper, we studied that process to try to understand how close a planet can get before it’s ripped apart and what might happen as it’s being ripped apart. The upshot of our study is that planets might get ripped apart a little farther from their stars than is often assumed BUT that ripping-apart process might proceed fairly slowly, over billions of years.