HD 240210
Encyclopedia
HD 240210 is a star
in the constellation
of Cassiopeia
. On June 10, 2009 an extrasolar planet
, designated HD 240210 b
, was discovered in orbit.
Star
A star is a massive, luminous sphere of plasma held together by gravity. At the end of its lifetime, a star can also contain a proportion of degenerate matter. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth...
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 Cassiopeia
Cassiopeia (constellation)
Cassiopeia is a constellation in the northern sky, named after the vain queen Cassiopeia in Greek mythology, who boasted about her unrivalled beauty. Cassiopea was one of the 48 constellations listed by the 2nd century Greek astronomer Ptolemy, and it remains one of the 88 modern constellations today...
. On June 10, 2009 an extrasolar planet
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...
, designated HD 240210 b
HD 240210 b
HD 240210 b is a 6.9 Jupiter-mass exoplanet discovered on June 10, 2009 by Niedzielski et al. using the Hobby-Eberly Telescope. It orbits the K3 giant star HD 240210 in the constellation of Cassiopeia. Its average orbital separation is at 1.33 Astronomical Units away from its star with a year of...
, was discovered in orbit.