Propus is a red supergiant at the foot of Castor in Gemini, a swollen, slowly varying star whose Greek name means the forward foot.
At a glance
| type | red giant (class M) |
|---|---|
| distance from the Sun | 385 light-years (118 pc) |
| its light left it | 385 years ago |
| luminosity | 3,170 × the Sun |
| radius | 167 × the Sun |
| surface temperature | 3,350 K |
| constellation | Gemini (Twins) |
Read off the piece’s own catalogue, the same values it draws with.
About Propus
Propus is a cool red star, vastly larger than the Sun, its surface so extended that its brightness wavers irregularly as it pulsates. It also has a companion that passes in front of it, so its light changes in more than one way.
The name is Greek for the forward foot: Propus stands at the foot of Castor, the western twin, just ahead of Tejat. Close by on the sky lies the star cluster M35, easy in binoculars.
What you see in the piece
Propus glows red in the piece because it is cool; Tejat beside it is a similar star, and flying out the twin’s feet drift apart while M35 lies far behind both.
Questions
What does Propus mean?
Propus is Greek for the forward foot; it marks the foot of Castor in Gemini.