Meet a star / Ursa Major

Muscida

Muscida is a yellow star, much like the Sun in temperature, in the constellation Ursa Major. It is a bright giant: a star that has left the steady part of its life and swollen up.

A drawing in the star's own colour, worked out from its measured colour index. It is not a photograph.

How far

180 light years

The light you see from Muscida tonight set off about 180 years ago. Everything we know about it is that much out of date.

How bright

120 Suns

It gives out 120 times as much visible light as the Sun. It is easy to see by eye on a clear night.

Astronomers put its brightness in our sky at magnitude 3.35. Smaller numbers are brighter, and the faintest stars the eye can see are about 6.

How hot

About 5,100 K

That is the temperature of its surface, worked out from its colour, so it is a guide and not a measurement. It could be out by a few hundred degrees. 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.

MuscidaThe Sun

In your sky now

Working it out…

Its names

Its own name
Muscida
By constellation (Bayer)
Omicron Ursae Majoris
Hipparcos catalogue
HIP 41704
Henry Draper catalogue
HD 71369
Spectral type
G4II-III

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 worked out here from the colour with the formula of Ballesteros (2012), and the words are written for this site.

To read more: Colour and brightness, How stars live and die, Measuring distance.