NASA’s Transiting Exoplanet Survey Satellite, a planet-seeking satellite that launched aboard a SpaceX Falcon 9 rocket last April, has found three new worlds that orbit a nearby dwarf star that is both smaller and cooler than our own Sun.
The newfound planets range in size and temperature, but are all bigger than Earth and with a higher temp on average — which are calculated only based on their distance from the star they orbit, and its energy output, without factoring in any atmospheric effects since it’s not yet known whether they have atmospheres at all. At the low end, there’s TOI 270 d, which has an average temp of 150 F — almost three times Earth’s own.
Both TOI 270 d, the farthest from its own system’s central star, and TOI 270 c, its nearest neighbor, are thought to be primarily gaseous and most closely resemble Neptune in our own Solar System. These aren’t really equivalent, however, as they’re much smaller, and researchers at NASA say they’re actually more likely new types of planets not seen anywhere in our own local solar backyard.
The planets overall are interesting to researchers because they are all between 1.5 and just over 2 times the size of Earth, which is actually an unusual size for planets to be when considered overall. The TOI 270 system is also pretty much perfectly positioned for study by the forthcoming James Webb Space Telescope, so it presents a great opportunity for future research once that space-based observatory gets up and running in 2021.