HD 45350 b
Encyclopedia
HD 45350 b is an extrasolar planet
located approximately 160 light-year
s away in the constellation
of Auriga
. It has a minimum mass
about 1.79 times that of Jupiter
. The mean distance of the planet from the star is more than the distance between Mars
and the Sun
, but the eccentricity of the orbit is nothing short of remarkable; at periastron the planet is as close to the star as Mercury
is from the Sun, but at apastron it is 8 times further. No doubt season
s on the planet would be extreme.
Dynamical simulations covering a period of 107 years show that a second, low-mass, planet could only orbit stably if it were no more than 0.2 AU
away from the star; in the simulations, these planets show oscillations in eccentricity up to an eccentricity of 0.25. Radial velocity
observations rule out any such planet whose mass is greater than 4 Neptune masses.
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...
located approximately 160 light-year
Light-year
A light-year, also light year or lightyear is a unit of length, equal to just under 10 trillion kilometres...
s 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 Auriga
Auriga (constellation)
Auriga is a constellation in the northern sky. Its name is Latin for 'charioteer' and its stars form a shape that has been associated with the pointed helmet of a charioteer. It was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and remains among the 88 modern...
. It has a minimum mass
Minimum mass
In astronomy, minimum mass is the lower-bound calculated mass of observed objects such as planets, stars and binary systems, nebulae, and black holes. Minimum mass is a widely cited statistic for extrasolar planets...
about 1.79 times that of Jupiter
Jupiter
Jupiter is the fifth planet from the Sun and the largest planet within the Solar System. It is a gas giant with mass one-thousandth that of the Sun but is two and a half times the mass of all the other planets in our Solar System combined. Jupiter is classified as a gas giant along with Saturn,...
. The mean distance of the planet from the star is more than the distance between Mars
Mars
Mars is the fourth planet from the Sun in the Solar System. The planet is named after the Roman god of war, Mars. It is often described as the "Red Planet", as the iron oxide prevalent on its surface gives it a reddish appearance...
and the Sun
Sun
The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...
, but the eccentricity of the orbit is nothing short of remarkable; at periastron the planet is as close to the star as Mercury
Mercury (planet)
Mercury is the innermost and smallest planet in the Solar System, orbiting the Sun once every 87.969 Earth days. The orbit of Mercury has the highest eccentricity of all the Solar System planets, and it has the smallest axial tilt. It completes three rotations about its axis for every two orbits...
is from the Sun, but at apastron it is 8 times further. No doubt season
Season
A season is a division of the year, marked by changes in weather, ecology, and hours of daylight.Seasons result from the yearly revolution of the Earth around the Sun and the tilt of the Earth's axis relative to the plane of revolution...
s on the planet would be extreme.
Dynamical simulations covering a period of 107 years show that a second, low-mass, planet could only orbit stably if it were no more than 0.2 AU
Astronomical unit
An astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....
away from the star; in the simulations, these planets show oscillations in eccentricity up to an eccentricity of 0.25. Radial velocity
Radial velocity
Radial velocity is the velocity of an object in the direction of the line of sight . In astronomy, radial velocity most commonly refers to the spectroscopic radial velocity...
observations rule out any such planet whose mass is greater than 4 Neptune masses.