The new world, named K2-288Bb, was found using data from NASA's now defunct Kepler space telescope.
The super-Earth is roughly twice the size of the planet where life exists.
"We know a lot about atmospheres of hot planets, but because it's very hard to find small planets that orbit farther from their stars and are therefore cooler, we haven't been able to learn much about these smaller, cooler planets", she said.
It looks like HD 21749b may not be alone in its system as scientists also believe there is a second planet there that is about the size of the Earth. MIT Kavli Institute's Chelsea Huang described it as a "lava world" as some of the exoplanet's rocky surface is very close to its star. Possible planets can be spotted by studying dips in light when the planet moves before its star.
Moreover, the planet known as K2-288Bb could either be rocky or a gas-rich planet similar to Neptune in our own solar system. Unfortunately, the author's also point out the HD 21749b likely is not an ideal target for future atmospheric follow-ups with the upcoming James Webb Space Telescope (JWST). According to researchers, HD 21749b is 53 light-years away from Earth and orbits a bright star in the Reticulum constellation with a 36-day orbit. If confirmed, it could be the smallest TESS planet to date.
TESS's four cameras, designed and built by MKI and MIT's Lincoln Laboratory in Lexington, Massachusetts, spend almost a month monitoring each observing sector, a single swath of the sky measuring 24 by 96 degrees.
Transits occur when one celestial body passes in front of a larger one, and help pinpoint other worlds.
-The TESS searches for planets orbiting distant stars.
In its primary two-year mission, TESS will observe almost the whole sky, providing a rich catalog of worlds around nearby stars.
But in its month-long stare into each sector, TESS records many additional phenomena, including comets, asteroids, flare stars, eclipsing binaries, white dwarf stars and supernovae, resulting in an astronomical treasure trove. NASA launched it in April past year. Unlike the Pi Mensae, this star is only one-fifth the size of our Sun.
While NASA's Transiting Exoplanet Survey Satellite is the newest space-based planet hunter, this new finding shows that more discoveries await scientists in Kepler data. "We're only halfway through TESS's first year of operations, and the data floodgates are just beginning to open", he said. TESS will operate for two years and will manage to examine nearly the entire sky in that time.