Struve 2398 A is one of a pair of red dwarfs in Draco, catalogued as a double star by Wilhelm Struve and invisible to the naked eye.
At a glance
| type | red dwarf (class M) |
|---|---|
| distance from the Sun | 11.5 light-years (3.52 pc) |
| its light left it | 11.5 years ago |
| luminosity | 0.0234 × the Sun |
| radius | 0.35 × the Sun |
| surface temperature | 3,440 K |
Read off the piece’s own catalogue, the same values it draws with.
About Struve 2398 A
Struve 2398 A is a red dwarf orbiting a slightly smaller red dwarf companion, Struve 2398 B. Wilhelm Struve, who surveyed the northern sky for double stars with one of the finest telescopes of his day, listed the pair in his catalogue; its number there is the one it still carries. The two lie close together on the sky in Draco and are too faint to see without a telescope.
Both stars are ordinary, mildly active red dwarfs. Each has a cool, dim surface and will burn its hydrogen slowly for far longer than the Sun. Seen from a planet around one of them, the other would be a bright orange-red star, outshining everything else in the sky.
What you see in the piece
Fly to it and you find a dull orange-red disc, with the planets catalogued around it drawn on their orbits. In HUMAN EYE there is nothing to see in this part of Draco.
Measured or modelled
Planets have been reported around both stars from radial-velocity measurements and are listed in planet catalogues, but they are small signals that further data could revise.
Questions
How far away is Struve 2398?
Struve 2398 A is 11.5 light-years (3.52 pc) from the Sun.