HD 231701 b
Encyclopedia
HD 231701 b is an extrasolar planet
approximately 354 light years away in the constellation
of Sagitta. This planet orbits at 0.55 AU from the star HD 231701
with eccentricity
0.19. Based on its high mass of 1.08 MJ, the planet is probably a gas giant
, meaning the planet has no solid surface and have composition similar to solar system
's outer planets
.
Extrasolar planet
An extrasolar planet, or exoplanet, is a planet outside the Solar System. A total of such planets have been identified as of . It is now known that a substantial fraction of stars have planets, including perhaps half of all Sun-like stars...
approximately 354 light years away in the constellation
Constellation
In modern astronomy, a constellation is an internationally defined area of the celestial sphere. These areas are grouped around asterisms, patterns formed by prominent stars within apparent proximity to one another on Earth's night sky....
of Sagitta. This planet orbits at 0.55 AU from the star HD 231701
HD 231701
HD 231701 is a yellow-white dwarf star approximately 354 light years away in the constellation of Sagitta. It is a 9th magnitude star, meaning the star is not visible to the naked eye, but powerful binoculars or a small telescope is needed to view the star...
with eccentricity
Orbital eccentricity
The orbital eccentricity of an astronomical body is the amount by which its orbit deviates from a perfect circle, where 0 is perfectly circular, and 1.0 is a parabola, and no longer a closed orbit...
0.19. Based on its high mass of 1.08 MJ, the planet is probably a gas giant
Gas giant
A gas giant is a large planet that is not primarily composed of rock or other solid matter. There are four gas giants in the Solar System: Jupiter, Saturn, Uranus, and Neptune...
, meaning the planet has no solid surface and have composition similar to solar system
Solar System
The Solar System consists of the Sun and the astronomical objects gravitationally bound in orbit around it, all of which formed from the collapse of a giant molecular cloud approximately 4.6 billion years ago. The vast majority of the system's mass is in the Sun...
's outer planets
Outer planets
The outer planets are those planets in the Solar System beyond the asteroid belt, which typically refers to these gas giant planets in order of their distance from the Sun:...
.