K2-3

Last updated
K2-3
Observation data
Epoch J2000       Equinox J2000
Constellation Leo [1]
Right ascension 11h 29m 20.39171s [2]
Declination −01° 27 17.2817 [2]
Apparent magnitude  (V)12.168±0.009 [3]
Characteristics
Spectral type M0V [4]
B−V color index 1.35 ± 0.06 [4]
Astrometry
Radial velocity (Rv)30.24±0.46 [2]  km/s
Proper motion (μ)RA: 94.116  mas/yr [2]
Dec.: −78.003  mas/yr [2]
Parallax (π)22.7374 ± 0.0220  mas [2]
Distance 143.4 ± 0.1  ly
(43.98 ± 0.04  pc)
Details [5]
Mass 0.549+0.029
−0.027
  M
Radius 0.546+0.018
−0.016
  R
Luminosity (bolometric)0.0587+0.0018
−0.0019
  L
Surface gravity (log g)4.704+0.023
−0.026
  cgs
Temperature 3844+61
−63
  K
Metallicity [Fe/H]−0.157+0.075
−0.080
  dex
Rotation 40±2 d [6]
Age 6.9±4.7  Gyr
Other designations
Gaia DR3  3796690380302214272, EPIC  201367065, 2MASS J11292037-0127173, WISE J112920.45-012718.0 [7]
Database references
SIMBAD data

K2-3, also known as EPIC 201367065, [4] is a red dwarf star with three known planets. It is on the borderline of being a late orange dwarf/K-type star, but because of its temperature, it is classified as a red dwarf (4,000 K is typically the division line between spectral class M and K).

At a distance of 143 light-years (44 parsecs ), [2] the star's proximity means it is bright enough to make it feasible for astronomers to study the planets' atmospheres to determine whether they are like Earth's atmosphere and possibly conducive to life.

Planetary system

K2-3 has three confirmed exoplanets, discovered in 2015. [8] All are low-density super-Earths or sub-Neptunes, with the outermost orbiting near the inner edge of the habitable zone. [9] [5]

The K2-3 planetary system [5] [10]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b 5.11+0.65
−0.64
  M🜨
0.0778±0.002610.054626(0)<0.09489.588+0.12
−0.100
°
2.078+0.076
−0.067
  R🜨
c 2.68±0.85  M🜨 0.1414±0.004724.646582(39)<0.09589.905+0.066
−0.088
°
1.582+0.057
−0.051
  R🜨
d <1.6  M🜨 0.2097±0.007044.556456(97)<0.09789.788+0.033
−0.029
°
1.458+0.056
−0.051
  R🜨

Related Research Articles

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<span class="mw-page-title-main">WASP-4</span> G-type main sequence star in the constellation Phoenix

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HAT-P-4 is a wide binary star consisting of a pair of G-type main-sequence stars in the constellation of Boötes. It is also designated BD+36°2593.

HAT-P-33 is a late-F dwarf star. It is orbited by a planet called HAT-P-33b. A search for a binary companion star using adaptive optics at the MMT Observatory was negative.

HD 106515 is a binary star in the constellation of Virgo.

Kepler-29 is a Sun-like star in the northern constellation of Cygnus. It is located at the celestial coordinates: Right Ascension 19h 53m 23.6020s, Declination +47° 29′ 28.436″. With an apparent visual magnitude of 15.456, this star is too faint to be seen with the naked eye. It is a solar analog, having a close mass, radius, and temperature as the Sun. Currently the age of the star has not been determined due to its 2780 light-year distance. As of 2016 no Jovian exoplanets of 0.9–1.4 MJ have been found at a distance of 5 AU.

Gliese 880 is a red dwarf star in the northern constellation of Pegasus that may host an exoplanetary companion. No stellar companions to Gliese 880 have been discovered as of 2020.

K2-3c, also known as EPIC 201367065 c, is an exoplanet orbiting the red dwarf star K2-3 every 24 days. It is 143 light-years away. It has a density of about 3.7 g/cm3, indicating that it could be an ocean world or a mini-Neptune. It is the second-smallest planet in the system by both radius and mass, with a mass almost three times that of Earth.

<span class="mw-page-title-main">K2-3d</span> Mini-Neptune orbiting K2-3

K2-3d, also known as EPIC 201367065 d, is a confirmed exoplanet of probable mini-Neptune type orbiting the red dwarf star K2-3, and the outermost of three such planets discovered in the system. It is located 143 light-years away from Earth in the constellation of Leo. The exoplanet was found by using the transit method, in which the dimming effect that a planet causes as it crosses in front of its star is measured. It was the first planet in the Kepler "Second Light" mission to receive the letter "d" designation for a planet. Its discovery was announced in January 2015.

GJ 9827 is a star in the constellation of Pisces. It is a K-type main-sequence star with an apparent magnitude of 10.250. It is 97 light-years away, based on parallax.

K2-19 is an early K-type or late G-type main sequence star that is magnetically active, and has a light curve that exhibits variations in brightness of ~1%. It is located approximately 976 light-years away in the constellation Virgo. Three confirmed transiting exoplanets are known to orbit this star.

<span class="mw-page-title-main">K2-18</span> Red dwarf star in the constellation Leo

K2-18, also known as EPIC 201912552, is a red dwarf star with two planetary companions located 124 light-years from Earth, in the constellation of Leo.

K2-24 is a metal-rich G3-type main sequence star larger and more massive than the Sun, located 560 light-years away in the constellation Scorpius. Two confirmed transiting exoplanets are known to orbit this star. An attempt to detect stellar companions using adaptive optics imaging at the Keck telescope was negative however later observations using lucky imaging at the Danish 1.54 m telescope at La Silla Observatory detected a possible companion at 3.8 arcseconds distance from K2-24. This candidate companion being over 8 magnitudes fainter than K2-24 and with a color temperature of 5400 Kelvin, is inconsistent with a bound main sequence companion.

L 98-59 is a bright M dwarf star, located in the constellation of Volans, at a distance of 10.608 parsecs, as measured by Gaia.

<span class="mw-page-title-main">K2-25</span>

K2-25 is a young red dwarf star located in the Hyades cluster. There is a single known Neptune-sized planet in a 3.5 day orbit.

References

  1. Roman, Nancy G. (1987). "Identification of a Constellation From a Position". Publications of the Astronomical Society of the Pacific. 99 (617): 695–699. Bibcode:1987PASP...99..695R. doi: 10.1086/132034 . Vizier query form
  2. 1 2 3 4 5 6 7 Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv: 2208.00211 . Bibcode:2023A&A...674A...1G. doi: 10.1051/0004-6361/202243940 . S2CID   244398875. Gaia DR3 record for this source at VizieR.
  3. Henden, A. A.; et al. (2016). "VizieR Online Data Catalog: AAVSO Photometric All Sky Survey (APASS) DR9 (Henden+, 2016)". VizieR On-line Data Catalog: II/336. Originally Published in: 2015AAS...22533616H. 2336. Bibcode:2016yCat.2336....0H. Vizier catalog entry
  4. 1 2 3 "K2-3 PLANET HOST OVERVIEW PAGE". NASA Exoplanet Archive. Retrieved 2015-10-17.
  5. 1 2 3 Diamond-Lowe, Hannah; et al. (2022), "The K2-3 System Revisited: Testing Photoevaporation and Core-powered Mass Loss with Three Small Planets Spanning the Radius Valley", The Astronomical Journal, 164 (5): 172, arXiv: 2207.12755 , Bibcode:2022AJ....164..172D, doi: 10.3847/1538-3881/ac7807 , S2CID   251067119
  6. Kosiarek, Molly R.; et al. (2019). "Bright Opportunities for Atmospheric Characterization of Small Planets: Masses and Radii of K2-3 b, c, and d and GJ3470 b from Radial Velocity Measurements and Spitzer Transits". The Astronomical Journal. 157 (3) 97. arXiv: 1812.08241 . Bibcode: 2019AJ....157...97K . doi: 10.3847/1538-3881/aaf79c . S2CID   119440420.
  7. "K2-3". SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 2024-04-19.
  8. Crossfield, Ian J. M.; et al. (2015). "A Nearby M Star with Three Transiting Super-Earths Discovered by K2". The Astrophysical Journal. 804 (1) 10. arXiv: 1501.03798 . Bibcode: 2015ApJ...804...10C . doi: 10.1088/0004-637X/804/1/10 .
  9. Damasso, Mario; et al. (2018). "Eyes on K2-3: A system of three likely sub-Neptunes characterized with HARPS-N and HARPS". Astronomy and Astrophysics. 615 A69. arXiv: 1802.08320 . Bibcode: 2018A&A...615A..69D . doi: 10.1051/0004-6361/201732459 . S2CID   58923147.
  10. Bonomo, A. S.; Dumusque, X.; et al. (April 2023). "Cold Jupiters and improved masses in 38 Kepler and K2 small-planet systems from 3661 high-precision HARPS-N radial velocities. No excess of cold Jupiters in small-planet systems". Astronomy & Astrophysics . arXiv: 2304.05773 . doi:10.1051/0004-6361/202346211. S2CID   261556620.