HD 38283 b

HD 38283 b

Exoplanet		List of exoplanets
Parent star
Star		HD 38283
Constellation		Mensa
Right ascension	(α)	05^h 37^m 02^s
Declination	(δ)	−73° 41′ 58″
Distance		123 ± 3 ly (37.7 ± 0.9 pc)
Spectral type		F9.5V
Mass	(m)	1.085 ± 0.02[1] M☉
Temperature	(T)	5945 ± 100[1] K
Metallicity	[Fe/H]	−0.24 ± 0.07[1]
Age		5.4 ± 1.5[1] Gyr
Orbital elements
Semi-major axis	(a)	1.02 ± 0.07[1] AU (153 Gm)
Periastron	(q)	0.60 AU (90 Gm)
Apastron	(Q)	1.44 AU (216 Gm)
Eccentricity	(e)	0.41 ± 0.16
Orbital period	(P)	363.2 ± 1.6[1] d (0.994 y)
Orbital speed	(υ)	29.78 km/s
Time of periastron	(T0)	2450802.6 ± 12[1] JD
Physical characteristics
Minimum mass	(m sin i)	0.34 ± 0.02[1] MJ
Discovery information
Discovery date		2011-04-11
Discoverer(s)		Tinney et al.
Discovery method		Radial velocity
Discovery site		Anglo-Australian Observatory
Discovery status		Published[1]
Database references
Extrasolar Planets Encyclopaedia		data
SIMBAD		data
Exoplanet Archive		data
Open Exoplanet Catalogue		data

HD 38283 b is an extrasolar planet, orbiting the 7th magnitude F-type main-sequence star HD 38283, 123 light years away in the constellation Mensa. It is a Saturn-like planet orbiting at Earth-like distance in the middle of its habitable zone. But its eccentricity is 0.41, much higher than the Earth's eccentricity of 0.017. The planet's distance ranges from about 0.60 AU (closer to its star than Venus is to the Sun) and 1.44 AU (nearly as distant from its star as Mars is to the Sun). This planet takes 363.2 days to orbit the star, just two days shy of the Earth's orbital period of 365.256366 days. Its mass is one-thirds that of Jupiter but its size and density are not known. Since inclination is not known, its actual mass is unknown, either slightly greater or much greater than its lower limit.

This planet may have Earth-like moons with bodies of water and possibly life. But giving the planet's high eccentricity, life on the moons may not evolve as well as those on Earth. From the surface of the moon, ones may see parent planet in the sky about half of the times with different phases just like the Moon seen from Earth, as well as other moons. If this planet has rings nearly as prominent as Saturn's, then the rings can be seen surrounding the planet, making this scenery even more amazing.

HD 38283 b was discovered on 11 April 2011 using the radial velocity technique using the Anglo-Australian Telescope (AAT). This method uses to look for planets by watching the star periodically wobble caused by the gravitational tug of the orbiting planets.^[1]

References

1. Tinney; et al. (April 2011). "The Anglo-Australian Planet Search. XXI. A Gas-giant Planet in a One Year Orbit and the Habitability of Gas-giant Satellites". The Astrophysical Journal. Bibcode:2011ApJ...732...31T. doi:10.1088/0004-637x/732/1/31.

Coordinates: 05^h 37^m 02^s, −73° 41′ 58″