Dschubba is the hot blue-white star at the centre of the scorpion’s head that unexpectedly brightened and became a star shedding a disc of gas.
At a glance
| type | blue-white star (class B) |
|---|---|
| distance from the Sun | 491 light-years (151 pc) |
| its light left it | 491 years ago |
| luminosity | 34,300 × the Sun |
| radius | 7.33 × the Sun |
| surface temperature | 29,000 K |
| constellation | Scorpius (Scorpion) |
Read off the piece’s own catalogue, the same values it draws with.
About Dschubba
Dschubba is a blue-white star of class B, one of the hottest bright stars of Scorpius and enormously more luminous than the Sun. It spins very fast. For a long time it was thought steady, until it unexpectedly brightened, changing the familiar look of the scorpion’s head, and it has varied irregularly since.
The brightening came as the star began throwing off a disc of gas around its equator, turning it into what astronomers call a Be star. A companion on an elongated orbit is thought to play a part. Its name comes from the Arabic for forehead, the scorpion’s brow.
What you see in the piece
In the piece Dschubba is drawn at its catalogue brightness, a blue-white point at the centre of the arc of Acrab, Fang and Iklil, its siblings in the Scorpius–Centaurus association.
Measured or modelled
How much the disc and the companion each contribute to Dschubba’s outbursts is still studied; its brightness is not fixed.
Questions
Why did Dschubba brighten?
It began shedding a disc of gas around its equator, making it a Be star. It is a blue-white star (class B) 491 light-years (151 pc) from the Sun.