K2-315b
Discovery[1] | |
---|---|
Discovered by | Kepler(K2) |
Discovery date | 2020 |
Transit | |
Orbital characteristics[1] | |
0.02±0.00AU | |
3.14±0.00d | |
Inclination | 88.7°±0.2° |
Physical characteristics | |
0.95±0.06R🜨[1] | |
Mass | 0.81M🜨[2] |
Temperature | 460 ± 5 K (368.33 ± 9.00 °F; 186.85 ± 5.00 °C)[1] |
K2-315bis anexoplanetlocated 185.3light yearsaway from Earth in the southernzodiac constellationLibra.[3][4]It orbits thered dwarfK2-315.
Discovery
[edit]K2-315b was discovered in 2020 by astronomers in an observatory using the Kepler space telescope.[1]It is also nicknamed the "Pi Earth" because it takes approximately 3.14 days to orbit the host star.[5]
Physical properties
[edit]The planet is thought to be a small rocky planet, even though composition is unknown.[5]Since it orbits very close to its star, it is too hot to host life, due to it having a scorching temperature of 450K.Not much is known about it because it was just discovered, but it is similar to Earth, having a radius 95% that of Earth,[6]very similar toVenus,but has 81% Earth's mass.[2]
![](https://upload.wikimedia.org/wikipedia/commons/thumb/c/c1/K2-315_b.jpg/220px-K2-315_b.jpg)
Host star
[edit]Observation data EpochJ2000.0EquinoxJ2000.0(ICRS) | |
---|---|
Constellation | Libra[7] |
Right ascension | 15h12m05.1944s[8] |
Declination | −20° 06′ 30.5428″[8] |
Apparent magnitude(V) | 17.67[9] |
Characteristics | |
Evolutionary stage | Red dwarf |
Spectral type | M3.5±0.5 V[10] |
Astrometry | |
Radial velocity(Rv) | 6.25±0.17[10]km/s |
Proper motion(μ) | RA:−120.013mas/yr[8] Dec.:+74.471mas/yr[8] |
Parallax(π) | 17.6353 ± 0.0492mas[8] |
Distance | 184.9 ± 0.5ly (56.7 ± 0.2pc) |
Details[10] | |
Mass | 0.174±0.004M☉ |
Radius | 0.2±0.01R☉ |
Luminosity | 0.398%L☉ |
Surface gravity(logg) | 5.094±0.006cgs |
Temperature | 3,300±30K |
Metallicity[Fe/H] | −0.24±0.09dex |
Rotational velocity(vsini) | <5 km/s |
Age | >1Gyr |
Other designations | |
Database references | |
SIMBAD | data |
K2-315is a star in the southern zodiacconstellationLibra.[11]It has anapparent magnitudeof 17.67,[9]requiring a powerful telescope to be seen. The star is relatively close at a distance of 185light years[8]but is receding with aradial velocityof6.25km/s.[10]
K2-315 has astellar classificationof M3.5±0.5 V, indicating that it is aM-type main-sequence star(with 14% uncertainty).[10]It has 17.4% themass of the Sunand 20% its radius.[10]Typical for red dwarves, it has a luminosity less than 1% of theSun,which yields aneffective temperatureof 3,300K.[10]Unlike most planetary hosts, K2-315 is metal-deficient, with anironabundance only 57% that of theSun.[10]It is estimated to be over a billion years old, and has aprojected rotational velocityless than5km/s.[10]
References
[edit]- ^abcdeNiraula, Prajwal; Julien de Wit; Rackham, Benjamin V.; Ducrot, Elsa; Burdanov, Artem; Crossfield, Ian J. M.; Valerie Van Grootel; Murray, Catriona; Garcia, Lionel J.; Alonso, Roi; Beard, Corey; Yilen Gomez Maqueo Chew; Delrez, Laetitia; Demory, Brice-Olivier; Fulton, Benjamin J.; Gillon, Michael; Gunther, Maximilian N.; Howard, Andrew W.; Issacson, Howard; Jehin, Emmanuel; Pedersen, Peter P.; Pozuelos, Francisco J.; Queloz, Didier; Rebolo-Lopez, Rafael; Sairam, Lalitha; Sebastian, Daniel; Thompson, Samantha; Triaud, Amaury H. M. J. (2020)."Π Earth: A 3.14 day Earth-sized Planet from K2's Kitchen Served Warm by the SPECULOOS Team".The Astronomical Journal.160(4): 172.arXiv:2006.07308.Bibcode:2020AJ....160..172N.doi:10.3847/1538-3881/aba95f.S2CID219635862.
- ^ab"Eyes On Exoplanets – Exoplanet Exploration: Planets Beyond our Solar System".exoplanets.nasa.gov.Retrieved2021-08-08.
- ^"Exoplanet-catalog".Exoplanet Exploration: Planets Beyond our Solar System.NASA.Retrieved2020-10-22.
- ^September 2020, Mike Wall 22 (22 September 2020)."'Pi planet' alien world takes 3.14 days to orbit its star ".Space.Retrieved2020-10-22.
{{cite web}}
:CS1 maint: numeric names: authors list (link) - ^abStarr, Michelle (22 September 2020)."Astronomers Discover" Pi Earth "Exoplanet Orbits Its Star Once Every 3.14 Days".ScienceAlert.Retrieved2020-10-21.
- ^"Exoplanet Archive".exoplanetarchive.ipac.caltech.edu.Retrieved2020-10-21.
- ^"Find the constellation which contains given sky coordinates".djm.cc.
- ^abcdeBrown, A. G. A.;et al. (Gaia collaboration) (2021)."GaiaEarly Data Release 3: Summary of the contents and survey properties ".Astronomy & Astrophysics.649:A1.arXiv:2012.01533.Bibcode:2021A&A...649A...1G.doi:10.1051/0004-6361/202039657.S2CID227254300.(Erratum:doi:10.1051/0004-6361/202039657e).Gaia EDR3 record for this sourceatVizieR.
- ^abMuirhead, Philip S.; Dressing, Courtney D.; Mann, Andrew W.; Rojas-Ayala, Bárbara; Lépine, Sébastien; Paegert, Martin; De Lee, Nathan; Oelkers, Ryan (4 April 2018)."A Catalog of Cool Dwarf Targets for the Transiting Exoplanet Survey Satellite".The Astronomical Journal.155(4): 180.arXiv:1710.00193.Bibcode:2018AJ....155..180M.doi:10.3847/1538-3881/aab710.eISSN1538-3881.
- ^abcdefghiNiraula, Prajwal; et al. (21 September 2020)."π Earth: A 3.14 day Earth-sized Planet from K2's Kitchen Served Warm by the SPECULOOS Team".The Astronomical Journal.160(4): 172.arXiv:2006.07308.Bibcode:2020AJ....160..172N.doi:10.3847/1538-3881/aba95f.eISSN1538-3881.ISSN0004-6256.
- ^"Odkryto" Ziemię Pi ". Okrąża swoją gwiazdę raz na 3,14 dnia".national-geographic.pl.