NASA's Transiting Exoplanet Survey Satellite, better known as TESS, has taken on the role of finding habitable planets outside of the solar system.
Kepler's mighty successor is expected to survey the night sky and observe about 400,000 stars to search for little dips of light that signals a planet transiting across its host star. However, astronomers from Cornell University, Lehigh University, and Vanderbilt University want to streamline the process.
According to a study published in The Astrophysical Journal Letters on Tuesday, March 26, TESS will take a closer look at 1,822 stars identified by the team in order to spot exoplanets similar to Earth.
Identifying Earth-Like Exoplanets
"Life could exist on all sorts of worlds, but the kind we know can support life is our own, so it makes sense to first look for Earth-like planets," stated Lisa Kaltenegger, director of Cornell University's Carl Sagan Institute and a member of the science team behind TESS. "This catalog is important for TESS because anyone working with the data wants to know around which stars we can find the closest Earth-analogs."
For the 1,822 stars, TESS is sensitive enough to spot planets that are slightly larger than Earth and receive radiation levels that are equivalent to what Earth receives from the sun. For 408 stars, the space telescope can observe planets that are about the same size as Earth and receive the same level of radiation from their host stars in one transit alone.
The catalog has also identified 227 stars for which the exoplanet hunter can probe for Earth-like planets that receive the same radiation from its star and look beyond for planets in Mars-like orbits.
The stars included in the study are cool dwarfs that have temperatures ranging between 2,700 and 5,000 degrees Kelvin. The closest star is just about six light-years away from Earth.
"We don't know how many planets TESS will find around the hundreds of stars in our catalog or whether they will be habitable but the odds are in our favor," said Kaltenegger. "Some studies indicate that there are many rocky planets in the habitable zone of cool stars, like the ones in our catalog. We're excited to see what worlds we'll find."
Search For Alien Life
The goal of the study is not to find as many Earth-like exoplanets, but to identify which can support and maybe already harbor alien life.
The work does not end with TESS. The 137 out of the over a thousand stars in the catalog will be in the continuous viewing zone of the upcoming James Webb Space Telescope which is scheduled to launch in 2021. The James Webb Space Telescope will be able to examine the atmosphere of exoplanets and even find the building blocks of life outside of Earth.
