Alpha Comae Berenices
Alpha Comae Berenices is a yellow-white star, a little hotter than the Sun, in the constellation Coma Berenices. It is in the long, steady part of its life, making helium from hydrogen in its core, as the Sun is.
How far
47 light years
The light you see from Alpha Comae Berenices tonight set off about 47 years ago. Everything we know about it is that much out of date.
How bright
1.5 Suns
It gives out 1.5 times as much visible light as the Sun. It can just be seen by eye from a really dark place.
Astronomers put its brightness in our sky at magnitude 5.17. Smaller numbers are brighter, and the faintest stars the eye can see are about 6.
How hot
About 6,600 K
That is the temperature of its surface, worked out from its spectral type, F5 V, with a standard table of how hot stars of each type are. It is a guide and not a measurement, and could be out by a tenth or so. The Sun's is 5,772 K. Hotter stars are bluer and cooler stars are redder, the same way a poker in a fire goes from red to white.
In your sky now
Working it out…
Its names
It has no name of its own. Its name by constellation is a Greek letter and the constellation it is in, a way of naming begun by Johann Bayer in 1603.
- By constellation (Bayer)
- Alpha Comae Berenices
- Henry Draper catalogue
- HD 114379
- Spectral type
- F5 V
Where this comes from
Distance, brightness, colour and spectral type are from the HYG star database, version 4.4, by David Nash, shared under a Creative Commons Attribution-ShareAlike 4.0 licence. Its distances are those measured by the Hipparcos satellite. The temperature is read from the spectral type with the table of Pecaut and Mamajek (2013), and the words are written for this site.
To read more: Colour and brightness, How stars live and die, Measuring distance.