HAT-P-12b

HAT-P-12b

Exoplanet		List of exoplanets
Size comparison of HAT-P-12b with Jupiter.
Parent star
Star		HAT-P-12
Constellation		Canes Venatici
Right ascension	(α)	13^h 57^m 434^s
Declination	(δ)	+43° 29′ 37″
Apparent magnitude	(mV)	12.84
Distance		464.77 ± 190 ly (142.5 ± 13.7 pc)
Spectral type		K4
Orbital elements
Semi-major axis	(a)	0.0384 ± 0.0003[1] AU
Eccentricity	(e)	0 (assumed)[1]
Orbital period	(P)	3.2130598 ± 0.0000021[1] d
Inclination	(i)	89.0 ± 0.4[1]°
Time of transit	(Tt)	2,454,419.19556 ± 0.00020[1] JD
Physical characteristics
Mass	(m)	0.211 ± 0.012[1] MJ
Radius	(r)	0.959 ± 0.029[1] RJ
Density	(ρ)	295 ± 25[1] kg m^−3
Discovery information
Discovery date		April 29, 2009
Discoverer(s)		Hartman et al.
Discovery method		Transit
Other detection methods		Radial velocity
Discovery site		Cambridge, Massachusetts
Discovery status		Published
Database references
Extrasolar Planets Encyclopaedia		data
SIMBAD		data
Exoplanet Archive		data
Open Exoplanet Catalogue		data

HAT-P-12b is an extrasolar planet approximately 465 light years away from Earth, orbiting the 13th magnitude K-type star HAT-P-12, which is located in Canes Venatici constellation. It is a transiting hot Jupiter that was discovered by the HATNet Project on April 29, 2009.

HAT-P-12b is a H/He-dominated gas giant planet with a core mass of 11.3+2.6
−2.1 M_⊕ and is moderately irradiated by its low-metallicity host star.^[2] Therefore, HAT-P-12b is most likely an H/He-dominated planet with a core of perhaps ~10 M_⊕, and a total metal fraction of ~15%. This makes HAT-P-12b the least massive H/He-dominated gas giant planet found to date; the previous record holder was Saturn.^[1]

References

1. Hartman, J. D.; et al. (2009). "HAT-P-12b: A Low-density sub-Saturn mass planet transiting a metal-poor K dwarf". The Astrophysical Journal 706 (1): 785–796. arXiv:0904.4704. Bibcode:2009ApJ...706..785H. doi:10.1088/0004-637X/706/1/785.
2. http://iopscience.iop.org/1538-3881/143/4/95/fulltext/

External links

Media related to HAT-P-12b at Wikimedia Commons

Coordinates: 13^h 57^m 434^s, +43° 29′ 37″