TOI-700 d explained

TOI-700 d
Discoverer:Emily Gilbert et al.
Discovered:3 January 2020
Discovery Method:Transit
Star:TOI-700
Single Temperature:Teq

268.8K

TOI-700 d is a near-Earth-sized exoplanet, likely rocky, orbiting within the habitable zone of the red dwarf TOI-700, the outermost planet within the system. It is located roughly 101.4ly away from Earth in the constellation of Dorado. The exoplanet is the first Earth-sized exoplanet in the habitable zone discovered by the Transiting Exoplanet Survey Satellite (TESS).

TOI-700 d orbits its star at a distance of 0.163AU from its host star with an orbital period of roughly 37.4 days and has a radius of around 1.19 times that of Earth. It has been estimated that the planet receives about 86% the energy that the Earth receives from the Sun.[1]

It was discovered in early January 2020 by the Transiting Exoplanet Survey Satellite (TESS).

Physical characteristics

Mass, radius and temperature

TOI-700 d is Earth-sized, an exoplanet that has a radius and mass similar to the Earth. It has a radius of about ; its mass has not been measured, but is predicted to be around . If it has an Earth-like atmosphere, then its average temperature would be about 268.8K. A small chance of a runaway greenhouse effect exists.

Host star

See main article: TOI-700. TOI-700 is a red dwarf of spectral class M that is about 40% the mass and radius, and very roughly 50% of the temperature of the Sun. The star is bright with low levels of stellar activity. Over the 11 sectors observed with TESS, the star does not show a single white-light flare. The low rotation rate is also an indicator of low stellar activity.

Orbit

TOI-700 d orbits its host star with an orbital period of 37.42 days. It has an orbital radius of about 0.163abbr=unitNaNabbr=unit, less than half of that of Mercury to the Sun in the Solar System. It receives about 86% of Earth's sunlight from its host star.

Habitability

TOI-700 d orbits in the habitable zone of its host star. The solar wind ram pressure and intensity of the interplanetary magnetic field are expected to be similar to the Earth's, therefore retention of the planetary atmosphere is likely.[2] [3]

History and discovery

TOI-700 d was discovered by a team of astronomers led by Emily Gilbert using the Transiting Exoplanet Survey Satellite (TESS) in early January 2020. This was the first Earth-sized exoplanet in the habitable zone discovered by TESS.[4]

See also

External links

Notes and References

  1. Web site: [VIDEO] TOI 700d : une planète de la taille de la Terre découverte dans une "zone habitable"]. midilibre.fr. fr. 2020-04-17.
  2. 2005.11587. Cohen. O.. Garraffo. C.. Moschou. S.. Drake. J.. Alvarado-Gomez. J.. Glocer. A.. Fraschetti. F.. The Space Environment and Atmospheric Joule Heating of the Habitable Zone Exoplanet TOI 700 D. The Astrophysical Journal. 2020. 897. 1. 101. 10.3847/1538-4357/ab9637. 2020ApJ...897..101C. 218869952 . free .
  3. 2005.13190. Dong. Chuanfei. Jin. Meng. Lingam. Manasvi. Atmospheric Escape from TOI-700 d: Venus versus Earth Analogs. The Astrophysical Journal. 2020. 896. 2. L24. 10.3847/2041-8213/ab982f. 2020ApJ...896L..24D. 219558481 . free .
  4. Web site: NASA's TESS Planet Hunter Finds Its 1st Earth-Size World in 'Habitable Zone'. . 7 January 2020.