The planet, discovered by TESS planet hunter, is known as 'TOI 700 d and its conditions could allow the presence of liquid water on the surface.
The TESS (Transiting Exoplanet Survey Satellite) planet hunter, which has been demonstrating its capabilities for two years by finding exoplanets and unknown regions within the vast universe, has identified its first Earth-sized exoplanet found in a habitable zone, NASA confirmed.
The planet, whose conditions could allow the presence of liquid water on the surface, is known as 'TOI 700 d', and is positioned as one of the few planets the size of the Earth discovered today.
TOI 700 is a small and cold dwarf star M located about 100 light years away, within the constellation of Dorado. The star is about 40 percent of the mass and size of our Sun, and almost half the surface temperature. TESS observed the star and its planets in 11 of the 13 sections it monitored during the first year of the mission.
Initially the star was mistakenly classified as larger and more similar to our Sun, and now thanks to new observations and data it has been possible to determine more precisely the characteristics of this system.
Data reveals that 'TOI 700 d' is the planet furthest from the star and is located in the habitable zone of the system. The nearest planet is 'TOI 700 b' and is almost the size of the Earth, it is believed to be rocky and completes an orbit every 10 days. On the other hand, 'TOI 700 c' is in the center and is 2.6 times larger than Earth, and it is believed to be a gaseous planet.
According to NASA data, 'TOI 700 d' is approximately 20 percent larger than Earth and orbits every 37 days. With these characteristics, 'TOI 700 d' joins the short list of planets believed to be located in "habitable zones", which include those of the TRAPPIST-1 system that was discovered in 2017.
��Discovery Alert!��— NASA Exoplanets (@NASAExoplanets) January 7, 2020
Meet three new exoplanets discovered by @NASA_TESS. One of the planets, TOI 700 d, is an Earth-sized�� world in its star's habitable zone (where liquid water�� *could* exist on the surface).
��TOI 700 b, c & d! We see you.https://t.co/92PlSDNnVQ pic.twitter.com/DCI5ySj7OY
One of the ways in which scientists can obtain a clearer picture of 'TOI 700 d' is through a technique called 'transit spectroscopy'. As the planet passes in front of its star, the star's light collides with the different molecules of its atmosphere, such as carbon dioxide or nitrogen, this serves to create distinctive spectral lines. Therefore, the study of these signals can shed light on how the conditions in 'TOI 700 d' could be.
It is expected that during this month the scientific observations will be completed with the aim of extracting new data, where it will be sought to determine if these planets have some kind of atmosphere, as well as the implementation of future missions that provide more detailed information.