An ancient group of six exoplanets whose orbits are unchanged for billions of years could tell us about how planetary systems like our own solar system formed.
In 2020, astronomers discovered a pair of resonant planets around the star HD110067, about 100 light-years away, using the Transiting Exoplanet Survey Satellite (TESS). But Luque and his team noticed there were other signals in the data that didn’t make sense. They followed up this observation a couple of years later with TESS and the space-based CHaracterising ExOPlanet Satellite (CHEOPS), and found a third planet, but the signals still weren’t fully explained.
The team looked at simulations of the signal that different combinations of resonant planets would produce — some planets will go around the star three times in the time that another takes two, for example. This revealed a system involving six planets, all orbiting in a flat plane, that almost perfectly fit the data.
