R Hydrae
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| Observation data Epoch J2000 Equinox J2000 |
|
|---|---|
| Constellation | Hydra |
| Right ascension | 13h 29m4 2.80s |
| Declination | -23° 16' 53.0" |
| Apparent magnitude (V) | 3.5 to 10.9 (variable)[2] |
| Characteristics | |
| Spectral type | M6e/M9e: |
| Variable type | Mira period= 388.87 days[2] |
| Astrometry | |
| Radial velocity (Rv) | −10.4[3] km/s |
| Details | |
| Mass | 2 M☉ |
| Radius | 460 R☉ |
R Hydrae, also known as R Hya[2], is a Mira-type variable star in the constellation Hydra.[3][2]
The magnitude of R Hydrae varies over a period of 389 days, between 3.21 and 11.00. The period of R Hydrae changes slowly.
At maximum brightness the star can be seen with the naked eye, while at minimum a telescope of at least 5 cm is needed.
R Hydrae is approximately 2000 light years from Earth. R Hydrae's spectral class is M7IIIe.[3]
