HD 202206 c
Encyclopedia
HD 202206 c is an extrasolar planet
discovered on November 16, 2004, using long-term observation of a formerly unconfirmed second planet after the discovery of a brown dwarf
(first companion) around the star
.
The planet orbits 3.07 times further out and is 7.13 times less massive than the first companion, having a semi-amplitude
of only 42 m/s. Its mass is 2.44 times that of Jupiter
and its diameter
is roughly the same size as Jupiter's. The orbital resonance
of the planet orbiting the brown dwarf is 5:1. The eccentricity of the planet is higher than that of all the planet
s and dwarf planet
s in our solar system
except Eris
, which has an eccentricity of 0.44.
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...
discovered on November 16, 2004, using long-term observation of a formerly unconfirmed second planet after the discovery of a brown dwarf
Brown dwarf
Brown dwarfs are sub-stellar objects which are too low in mass to sustain hydrogen-1 fusion reactions in their cores, which is characteristic of stars on the main sequence. Brown dwarfs have fully convective surfaces and interiors, with no chemical differentiation by depth...
(first companion) around the star
HD 202206
HD 202206 is a yellow dwarf star approximately 151 light-years away in the constellation Capricornus. The star is orbited by two companions with substellar masses in a near-resonant configuration.- Distance, age and metallicity :...
.
The planet orbits 3.07 times further out and is 7.13 times less massive than the first companion, having a semi-amplitude
Amplitude
Amplitude is the magnitude of change in the oscillating variable with each oscillation within an oscillating system. For example, sound waves in air are oscillations in atmospheric pressure and their amplitudes are proportional to the change in pressure during one oscillation...
of only 42 m/s. Its mass is 2.44 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,...
and its diameter
Diameter
In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints are on the circle. The diameters are the longest chords of the circle...
is roughly the same size as Jupiter's. The orbital resonance
Orbital resonance
In celestial mechanics, an orbital resonance occurs when two orbiting bodies exert a regular, periodic gravitational influence on each other, usually due to their orbital periods being related by a ratio of two small integers. Orbital resonances greatly enhance the mutual gravitational influence of...
of the planet orbiting the brown dwarf is 5:1. The eccentricity of the planet is higher than that of all the planet
Planet
A planet is a celestial body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighbouring region of planetesimals.The term planet is ancient, with ties to history, science,...
s and dwarf planet
Dwarf planet
A dwarf planet, as defined by the International Astronomical Union , is a celestial body orbiting the Sun that is massive enough to be spherical as a result of its own gravity but has not cleared its neighboring region of planetesimals and is not a satellite...
s in our 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...
except Eris
Eris (dwarf planet)
Eris, formal designation 136199 Eris, is the most massive known dwarf planet in the Solar System and the ninth most massive body known to orbit the Sun directly...
, which has an eccentricity of 0.44.