HD 177830

A K-type star in the constellation Lyra around which has been found an extrasolar planet. Discovered in 1999, this planet, HD 117830 b, is at least 1.28 times as massive as Jupiter, though it may be much more massive since the inclination of its orbit is not known. The mean distance of HD 117830 b from its host star is about the same as that of Earth from the Sun; however, its orbit is so eccentric that periastron (near point to the star) occurs at only half this distance whereas apoastron is as distant as Mars is from the Sun.

Host star
Distance	192.4 light-years (59.03 pc)
Spectral type	K0
Apparent magnitude	7.18
Position	R.A. 19h 5m 20.77s; Dec. +25° 55' 14.38"
Other catalog designations	BD+25°3719, HIP 93746

Planet
Mass (Jupiter=1)	>1.28
Semimajor axis	1.00 AU (150 million km, 93 million miles)
Orbital period	391 days
Eccentricity	0.43
Discovery	1999, Vogt, Marcy, et al
Method	radial velocity

Related categories

• NOTABLE STARS
• EXTRASOLAR PLANETS AND SUBSTELLAR OBJECTS

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