Struve 2398 A
Struve 2398 A is an orange star, cooler than the Sun, in the constellation Draco.
How far
12 light years
The light you see from Struve 2398 A tonight set off about 12 years ago. Everything we know about it is that much out of date.
How bright
0.00 of a Sun
It gives out one 340th of the Sun's visible light. It is too faint to see without a telescope.
Astronomers put its brightness in our sky at magnitude 8.94. Smaller numbers are brighter, and the faintest stars the eye can see are about 6.
How hot
About 3,800 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.
Struve 2398 AThe Sun
Its names
- Its own name
- Struve 2398 A
- Hipparcos catalogue
- HIP 91768
- Henry Draper catalogue
- HD 173739
- Spectral type
- K5
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.