Beta Hydri

From Wikipedia, the free encyclopedia

Beta Hydri
Observation data
Equinox J2000
Constellation Hydrus
Right ascension 00h 25m 45.1s
Declination -77° 15′ 15″
Apparent magnitude (V) 2.80
Characteristics
Spectral type G2 IV
U-B color index 0.11
B-V color index 0.61
Variable type Suspected
Astrometry
Radial velocity (Rv) 22.9 km/s
Proper motion (μ) RA: 2,220.12 mas/yr
Dec.: 324.37 mas/yr
Parallax (π) 133.86 ± 0.51 mas
Distance 24.37 ± 0.09 ly
(7.47 ± 0.03 pc)
Absolute magnitude (MV) 3.43
Details
Mass 1.1 M
Radius 1.9 R
Luminosity 3.53 L
Temperature 5,750 K
Metallicity 49-100%
Rotation 3.3 km/s. (~29 days)
Age 6.7 × 109 years
Other designations
Gl 19, HR 98, CD -77°15, HD 2151, LHS 6, LTT 226, GCTP 69, SAO 255670, CP(D)-77 16, FK5 11, LPM 22, LFT 43, HIP 2021.

Beta Hydri (β Hyi / β 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. Beta Hydri is often studied because it might give insights on what might happen to our Sun in the next 2.5 billion years.

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.

[edit] See also

[edit] External links


In other languages