HD 195019

From Wikipedia, the free encyclopedia

**HD 195019**
Observation data Epoch J2000.0
Constellation (pronunciation)	Delphinus
Right ascension	20^h 28^m 17^s
Declination	+18º 46' 12″
Apparent magnitude (V)	6.91
Absolute magnitude (V)	5.40
Distance	65 ly (20 pc)
Spectral type	G3IV-V
Other designations
HIP 100970, SAO 106138

HD 195019 is a star system in the constellation Delphinus. Star B is located approximately 150 AU from Star A. This star system is located 65 light years or 20 parsecs or 0.617 exameters away from the Sun, Earth, or Solar System. It is a yellow dwarf or subgiant [G3IV-V]. The useful catalogue numbers are HIP 100970, and SAO 106138.

In 1998, a planet was discovered by Lick Observatory, orbiting around Star A.

[edit] HD 195019 Ab

**HD 195019 Ab**
Orbital elements
Extrasolar planet		List of extrasolar planets
Semimajor axis	(a)	0.1388±0.008 AU
Eccentricity	(e)	0.014±0.0044
Orbital period	(P)	18.20163±0.0004 d
Angular distance	(θ)	6.94 mas
Longitude of periastron	(ω)	322±20°
Time of periastron	(T₀)	2,411,015±1.2 JD
Semi-amplitude	(K)	272.3±1.4 m/s
Physical characteristics
Mass	(m)	>3.7 M_J
Discovery information
Discovery date		1998
Discoverer(s)		Fischer et al.
Detection method		Radial Velocity
Discovery site		Lick Observatory
Discovery status		Published

HD 195019 Ab is an exoplanet orbiting around HD 195019 A in binary system. It is a superjovian planet, with minimum mass of 3.7 M_J. It orbits very close to the star, about the same distance as the hypothetized planet Vulcan from the Sun. Like many planets at close distance, it’s orbit is circular, even more circular or less eccentric than Earth. It takes 437 hours to orbit with velocity of 83.24 kilometers per second.