Astronomers are probing faraway planets with greater sophistication

IN THE DELUGETOITOITESSTOITESS of planets found beyond the solar system over the past decade, those of system -270 might not seem special. There are three of them, orbiting a star 73 light-years away. This is neither the closest system known, nor does it contain the most Earthlike exoplanet. It has, though, sent a buzz through astronomy.-270 was discovered earlier this year by the Transiting Exoplanet Survey Satellite, , an American instrument launched in 2018. ( stands for object of interest.) Its innermost world is a super-Earth, a rocky planet a little bigger than Earth that scurries around its parent star once every three days. Farther out, at orbits of around six and 11 days, are a pair of larger objects known as mini-Neptunes. Having representatives of these two types of planet in a single system is a valuable find. It should help astronomers understand a bit better how different sorts of planet form.