NGC 2423-3

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**NGC 2423-3**
Observation data Epoch J2000.0
Constellation (pronunciation)	Puppis
Right ascension	07^h 37^m 09^s
Declination	-13º 54' 24″
Apparent magnitude (V)	9.45
Absolute magnitude (V)	0.03
Distance	2498 ly (766 pc)
Spectral type	K-M III
Other designations
TYC 5409-2156-1

NGC 2423-3 (TYC 5409-2156-1) is a star located in the open cluster NGC 2423, located 2500 light years away in the constellation of Puppis. It is an apparent magnitude 9 red giant with absolute magnitude of 0. The star has a mass of 2.4 times solar.

In 2007, it was found to have a massive superjovian planet in orbit around it.

1 NGC 2423-3 b
2 References
3 See also
4 External links

[edit] NGC 2423-3 b

**NGC 2423-3 b**
Discovery
Discovered by	Lovis and Mayor
Discovery site	USA
Discovery date	July 2007
Detection method	doppler spectroscopy
Designations
Alternative names	TYC 5409-2156-1 b
Orbital characteristics
Periastron	1.66 AU
Apastron	2.54 AU
Semi-major axis	2.1 AU
Eccentricity	0.21±0.07
Orbital period	714.3±5.3 d
Average orbital speed	31.6 km/s
Angular distance	2.742 mas
Longitude of periastron	18±10°
Time of periastron	2,453,213±21 JD
Semi-amplitude	71.5 m/s
Physical characteristics
Mass	>10.6 M_J

NGC 2423-3 b (TYC 5409-2156-1 b) is an exoplanet that is 10.6 times more massive than Jupiter, even more massive than Pi Mensae b, which has a mass about 10.3 times Jupiter. Only the minimum mass is known since the orbital inclination is not known, it is likely to be a brown dwarf instead like NGC 4349-127 b. The planet orbits at 10.2 μpc, taking 1.956 years to orbit eccentrically around the star. Its eccentricity is about the same as Mercury, but less than Pluto. The planet has a semi-amplitude of 71.5 m/s since if 10.6 M_J planet orbits at 2.1 AU from 2.4 M_S star.

This planet was discovered by Chad Lovis and Michel Mayor in July 2007; which Lovis had also found three Neptune-mass planets around HD 69830 in May 2006, also in Puppis constellation.