Alpha Centauri B is the smaller partner of Alpha Centauri A, a cooler, more orange star that, with A, forms the closest pair of Sun-like stars to us.
At a glance
| type | orange star (class K) |
|---|---|
| distance from the Sun | 4.37 light-years (1.34 pc) |
| its light left it | 4.37 years ago |
| luminosity | 0.5 × the Sun |
| radius | 0.86 × the Sun |
| surface temperature | 5,260 K |
Read off the piece’s own catalogue, the same values it draws with.
About Alpha Centauri B
B is an orange star, a little smaller and cooler than the Sun, with a warmer tint than its yellow companion. The two stars circle a common centre on an elongated orbit, swinging from a little beyond Saturn’s distance from the Sun out to beyond Neptune’s, and each would show the other as a dazzling star in its sky. From Earth they merge into one bright point; a small telescope splits them.
B has a place in the history of planet hunting for a planet that turned out not to be there. A small world was announced around it from the faint wobble in its light, and later analysis showed the signal was an artefact of how the data had been handled. The episode is a reminder of how small these signals are.
What you see in the piece
Fly to the pair and B is the warmer-coloured of the two, slightly dimmer than A. The piece draws it as a star and nothing more: no planets have been confirmed around it.
Questions
How far away is Alpha Centauri B?
Alpha Centauri B is 4.37 light-years (1.34 pc) from the Sun, the same distance as its partner A.
Does Alpha Centauri B have planets?
None confirmed. A planet once announced around it was later shown to be a false signal.