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NASA mission discovered An Earth-sized exoplanet orbiting a small star about 100 light years away.
Dubbed TOI 700 e, the planet is probably rocky and 95% the size of our world. This object is her fourth planet detected orbiting the small, cold M dwarf TOI 700. exoplanet Discovered by NASA’s Transiting Exoplanet Survey Satellite (TESS mission).
Another planet in the system, discovered in 2020 and named TOI 700 d, is also the size of Earth. Both of these exoplanets may be in their star’s habitable zone, or just the right distance from the star, and have liquid water on their surface. The possible presence of liquid water suggests that the planet itself may be suitable for habitation of life, or may have once existed.
The discovery of a fourth planet was announced at the 241st Congress on Tuesday. American Astronomical Society In Seattle, a study on exoplanets was accepted for publication in The Astrophysical Journal Letters.
“This is one of the few systems that we know of that has multiple small habitable zone planets,” said Emily Gilbert, a postdoctoral fellow and principal investigator at NASA’s Jet Propulsion Laboratory in Pasadena, California. said.
“This makes the TOI 700 system an exciting prospect for additional follow-ups. Since planet e is about 10% smaller than planet d, this system will allow additional TESS observations to help find smaller worlds. It shows how it can help
Small, cool M dwarfs like TOI 700 are common in space. The TRAPPIST-1 system and its seven exoplanets Observed by the James Webb Space Telescope.
The closest to the star is TOI 700 b, which is 90% the size of Earth and makes one rapid orbit around the star every 10 Earth days. Then there’s the TOI 700c. It is 2.5 times larger than her on Earth and makes one orbit around the star every 16 days. Both of these planets are likely to be tidally locked, meaning they always show the same side to the stars, just as the same side of the Moon always faces Earth.
Two exoplanets in the stellar habitable zone, planets d and e, have long orbits of 37 and 28 days, respectively, due to their distance from the star. The newly announced planet e is actually located between planets c and d.
Launched in 2018, the TESS mission monitors most of the night sky 27 days at a time, gazing at the brightest stars and tracking changes in brightness. These dips in luminosity indicate that it orbits the planet as it passes in front of a star called a transit. The mission began observing the southern sky in 2018 and then turned to the northern sky. In 2020, the mission refocused on the southern sky for additional observations, revealing her fourth planet in the TOI 700 system.
“Had the star been a little closer, or the planet a little bigger, we might have been able to spot TOI 700 e in the first year of TESS data,” says the researcher, a doctoral student at the University of Maryland College. co-author Ben Hord said.Park and alumni Researchers at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, said: “But the signal was so faint that it took another year of transit observations to identify it.”
While researchers are using other space and ground-based observatories to track interesting planetary systems, more TESS data is pouring in.
“TESS has just completed its second year of northern sky observations,” said Allison Youngblood, a research astrophysicist and TESS sub-project scientist at Goddard. “We look forward to other exciting discoveries hidden in the mission’s treasure trove of data.”
