Gamma Geminorum
Sign in to saveAlso known as Alhena, 24 Geminorum, 24 Gem, γ Geminorum, γ Gem, HD 47105, HIP 31681, HIC 31681
star in the constellation Gemini
Astronomical data · SIMBAD
- Object type
- SB*
- Spectral type
- A1.5IV+
- Distance
- 109 light-years
- Redshift
- z = -0.00004212825782845542
- Coordinates
- RA 99.4280° · Dec 16.3993°
View on SIMBAD →
via SIMBAD · CDS Strasbourg
Key facts
- Constellation
- Gemini
- Right ascension
- 06 37 42.71050
- Declination
- +16 ° 23 ′ 57.4095 ″
- Evolutionary stage
- subgiant
- Spectral type
- A1IV + G
- U b color index
- +0.137
- B v color index
- +0.005
via Wikipedia infobox
Wikidata facts
- Constellation
- Gemini
- Distance from Earth
- 109
- Radius
- 4.4
- Mass
- 2.8
- Image
- Gemini constellation map.png
Show 16 more facts
- spectral class
- A1IVSB
- catalog code
- Renson 12640
- apparent magnitude
- 1.87
- metallicity
- -0.2
- right ascension
- 99.427960429
- declination
- 16.399280427
- effective temperature
- 9000
- radial velocity
- -2.8
- parallax
- 29.84
- epoch
- J2000.0
- stellar rotational velocity
- 12
- luminosity
- 160
- absolute magnitude
- -0.61
- surface gravity
- 10000
- right ascension component of proper motion
- 46
- declination component of proper motion
- -43
via Wikidata · CC0
~3 min read
Encyclopedic overview
Gamma Geminorum (γ Geminorum, abbreviated Gamma Gem, γ Gem), formally named Alhena /ælˈhiːnə/, is the third-brightest object in the constellation of Gemini. It has an apparent visual magnitude of 1.9, making it easily visible to the naked eye even in urban regions. Based upon parallax measurements with the Hipparcos satellite, it is located at a distance of roughly 109 light-years (33 parsecs).
Properties
Excerpted from Wikipedia’s “Gamma Geminorum” article, available under the CC BY-SA 4.0 licence.