Gl 15 Ab

Gl 15 Ab
Extrasolar planet List of extrasolar planets

An artist's impression of Gl 15 Ab
Parent star
Star Groombridge 34
Constellation Andromeda
Right ascension (α) 00h 18m 22.89s
Declination (δ) –44° 01 22.6
Apparent magnitude (mV) 8.09
Distance11.7±0.1 ly
(3.5 pc)
Spectral type M3.5 + M1.5v
Orbital elements
Semimajor axis(a) 0.717 AU
Eccentricity (e) 0.12
Orbital period(P) 0.01 y
Physical characteristics
Minimum mass(m sin i)1 M
Discovery information
Discovery date August, 2014
Discoverer(s) >Andrew Howard,
Discovery method HIRES
Discovery site Keck Observatory
Discovery status Published
Database references
Extrasolar Planets
Encyclopaedia
34&p2=b data
SIMBAD34+b data
Exoplanet Archive34+b data
Open Exoplanet Catalogue34+b data

Groombridge 34 Ab (Gl 15 Ab)[note 1] is an extrasolar planet approximately 11 light years away in the constellation of Andromeda, and is found in the night sky at Right ascension 00h 18m 22.89s and Declination +44° 01′ 22.6″[1] It was discovered in August 2014.[2] deduced from analysis of the radial velocities of the parent Star by the Eta-Earth Survey using HIRES at Keck Observatory. Planet "b" has around 5.35 ± 0.75 Earth masses,[2] and is thought to be a super earth with a probable diameter of at least 1.0 times the earths.

Planet b has a close inner orbit around Star A at a semi-major axis of only 0.0717 +/- 0.0034 Aus, making an orbital period that is a little longer than 11.4 days, which appears to be relatively circular (e= 0.12 +0.08/-0.06). It lies closer to the parent star than the probable habital zone and is expected to be unable to harbour life.

Notes

  1. Actually, in the discovery paper discoverers call this object "Gl 15 Ab", and never "Groombridge 34 Ab".

References

  1. F. van Leeuwen (2007) Validation of the new Hipparcos reduction. Astronomy and Astrophysics 474 (2): 653–664.
  2. 2.0 2.1 Andrew Howard, Geoffrey Marcy, Debra A. Fischer, Howard Isaacson, Philip S. Muirhead, Gregory W. Henry, Tabetha S. Boyajian, Kaspar von Braun, Juliette C. Becker, Jason T. Wright, John Asher Johnson, Astrophysics Earth and Planetary Astrophysics : The NASA-UC-UH Eta-Earth Program: IV. A Low-mass Planet Orbiting an M Dwarf 3.6 PC from Earth.