KOI-4878.01

KOI-4878.01

Artist's impression of KOI-4878.01
Discovery
Discovery site	Kepler space telescope
Discovery date	2015
Detection method	Transit
Orbital characteristics
Semi-major axis	1.125 AU (168,300,000 km)
Orbital period (sidereal)	449.015±0.021 d
Star	KOI-4878
Physical characteristics
Mean radius	1.05 R🜨
Temperature	−16.5 °C (256.6 K; 2.3 °F)

KOI-4878.01 is an exoplanet candidate that orbits the F-type main-sequence star KOI-4878. It is located about 1075 light years (329 parsecs) from Earth.^[1][2][3] The features of the planet are very similar to that of Earth, and if it is confirmed, it would be one of the most Earth-like planets found.^[4] The orbital period of the exoplanet is around 449 Earth days. It is very likely located within the habitable zone of its parent star.^[5][6]

Host star

Its host star is a F-type main-sequence star that is slightly less massive than the Sun, although it is about 5% larger and has a temperature of about 6031 K. The star is a V magnitude 12.4 star in the constellation Draco. Despite the unknown age of the star, its low metallicity and fairly high space velocity suggest that KOI-4878 is older than the Sun.^[7][8]

Exoplanet detection

An analysis of the Kepler space telescope's data from its first to the twelve quarter revealed three possible transit events equally spaced in time. A post-analysis in the Sixteen quarter showed that the events happened within a period of 449 days, they had a duration of 12 and half hours and a transit depth of 94 ppm.^[9]

Characteristics

Mass

KOI-4878.01's mass is somewhere between 1.4 - 3.0 Earth masses; likely about 1.9 Earth masses.^[10][11]

Radius

The exoplanet has a slightly larger radius than Earth: 1.05 Earth radii.^[12]

Temperature

It has an equilibrium temperature of 256 K (-16.5 °C; 2.3 °F), an average surface temperature of about 2.4 degrees C (4.3 degrees F) cooler than Earth, but it may have more greenhouse gases than Earth to trap heat. ^[13]

Properties of KOI-4878.01^[14]

Property	Based on KIC data	Based on new data
Period (days)	449.015±0.021	449.015±0.021
Semimajor Axis (AU)	1.137 +0.053/-0.040	1.125
Planet Radius (Earth=1)	1.04 +0.38/-0.14	1.05
Seff (Earth=1)	1.05	0.92

Habitability

The estimated features of the planet are similar to an Earth analog.^[15] It completes an orbit around its host star every 449 Earth days. Based on this, KOI-4878.01 should be in the habitable zone of the star.^[16][17]

See also

• Kepler space telescope
• Earth similarity index

References

1. Rowe, Jason F. (2015). "Planetary candidates observed by kepler v: planet sample from q1-q12 (36 months)". The Astrophysical Journal Supplement Series. 217 (1): 16. arXiv:1501.07286. Bibcode:2015ApJS..217...16R. doi:10.1088/0067-0049/217/1/16. S2CID 119204743.
2. "KOI-4878.01". NASA Exoplanet Archive. Retrieved 2020-09-30.
3. "KOI-4878.01". Simbad. Retrieved 2020-10-04.
4. "Open Exoplanet Catalogue - KOI-4878 b". www.openexoplanetcatalogue.com. Retrieved 2020-10-04.
5. "Life away from Earth" (PDF). El Faro del Saber - UNED Long-distance Learning University.
6. "KOI-4878.01: Kepler's Most Earth-like Planet Candidate?". Drew Ex Machina. 2019-09-05. Retrieved 2020-09-30.
7. "KOI-4878". exoplanetarchive.ipac.caltech.edu. Retrieved 2020-09-30.
8. Institute, CSIC. "Exoplanets in the Milky Way" (PDF).
9. "KOI-4878.01: Kepler's Most Earth-like Planet Candidate?". Drew Ex Machina. 2019-09-05. Retrieved 2020-10-01.
10. How the Universe Works: An Illustrated Guide to the Cosmos. Book Sales. 2017. ISBN 9780785835417.
11. Institute, CSIC. "Exoplanets in the Milky Way" (PDF).
12. "La NASA ha encontrado siete exoplanetas similares a la Tierra en los que buscar vida". El HuffPost (in Spanish). 2017-02-22. Retrieved 2020-10-01.
13. "KOI-4878.01". exoplanetarchive.ipac.caltech.edu. Retrieved 2020-09-30.
14. "KOI-4878.01: Kepler's Most Earth-like Planet Candidate?". Drew Ex Machina. 2019-09-05. Retrieved 2020-10-01.
15. Atargatis (2020-11-10). "Found more than 20 exoplanets that could host life". Atargatis.news (in Italian). Retrieved 2020-11-12.
16. Mendez, Abel. Potentially habitable worlds.
17. "Planetas habitables en los que nunca habitaremos". El Independiente (in Spanish). 2016-10-07. Retrieved 2020-10-04.