42 Draconis b
Encyclopedia
42 Draconis b is an extrasolar planet
located approximately 317 light years away in the constellation
of Draco
, orbiting the 5th magnitude
K-type giant
star
42 Draconis
. It takes 479 days to orbit the star in a 38% eccentricity
. This planet was discovered by radial velocity method on March 20, 2009, which was the first day of spring.
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 317 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 Draco
Draco (constellation)
Draco is a constellation in the far northern sky. Its name is Latin for dragon. Draco is circumpolar for many observers in the northern hemisphere...
, orbiting the 5th magnitude
Apparent magnitude
The apparent magnitude of a celestial body is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere...
K-type giant
Giant star
A giant star is a star with substantially larger radius and luminosity than a main sequence star of the same surface temperature. Typically, giant stars have radii between 10 and 100 solar radii and luminosities between 10 and 1,000 times that of the Sun. Stars still more luminous than giants are...
star
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...
42 Draconis
42 Draconis
42 Draconis is a 5th magnitude K-type giant star located approximately 317 light years away in the constellation of Draco. The star has mass similar to our Sun but its radius is 22 times greater. It is a metal-poor star with metallicity as low as 35% that of our Sun and its age is 9.49 billion years...
. It takes 479 days to orbit the star in a 38% 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...
. This planet was discovered by radial velocity method on March 20, 2009, which was the first day of spring.