HD 139357
Encyclopedia
HD 139357 is a 6th magnitude
K-type giant
star
located approximately 396 light years away in the constellation
of Draco
. Its mass is four thirds that of our Sun
but its radius is 11.47 times larger. However, despite being a giant star, it is only 3.07 billion years old, which is younger than our Sun.
It hosts a planet discovered in 2009.
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...
located approximately 396 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...
. Its mass is four thirds that of our 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 its radius is 11.47 times larger. However, despite being a giant star, it is only 3.07 billion years old, which is younger than our Sun.
It hosts a planet discovered in 2009.
See also
- 42 Draconis42 Draconis42 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...
- Iota DraconisIota DraconisIota Draconis is an orange giant star located away in the constellation Draco. A visually unremarkable star of apparent magnitude 3.31, it has recently been discovered to have a planet.-Name:...
- List of extrasolar planets
- List of stars in Draco