Beta Hydri
Encyclopedia
Beta Hydri is a star
in the constellation
Hydrus
. (Note that Hydrus is not the same as Hydra
.)
It is about 24.4 light years away from Earth. It is larger and slightly more massive than the Sun.
At around 150 BC, this star was two degrees away from the southern celestial pole. It is currently the nearest relatively bright star to the southern pole.
masses and orbital separation of roughly 8 AU
s could explain the observed trend. If confirmed, it would be a true Jupiter
-analogue, though 4 times more massive. So far no planetary/substellar object has been certainly detected.
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....
Hydrus
Hydrus
Hydrus is a small constellation in the southern sky, created in the sixteenth century. Its name means "male water snake", and it should not be confused with Hydra, a much larger constellation which represents a female water snake.-History:...
. (Note that Hydrus is not the same as Hydra
Hydra (constellation)
Hydra is the largest of the 88 modern constellations, measuring 1303 square degrees. It has a long history, having been included among the 48 constellations listed by the 2nd century astronomer Ptolemy. It is commonly represented as a water snake...
.)
It is about 24.4 light years away from Earth. It is larger and slightly more massive than the Sun.
At around 150 BC, this star was two degrees away from the southern celestial pole. It is currently the nearest relatively bright star to the southern pole.
A planetary system?
In 2002 Endl et al. inferred the possible presence of an unseen companion orbiting Beta Hydri as hinted by radial velocity linear trend with a periodicity exceeding 20 years. A substellar object with minimum mass of 4 JupiterJupiter
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,...
masses and orbital separation of roughly 8 AU
Astronomical unit
An astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....
s could explain the observed trend. If confirmed, it would be a true 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,...
-analogue, though 4 times more massive. So far no planetary/substellar object has been certainly detected.
See also
- List of nearest bright stars
- Beta Hydri in fiction