Seginus is a white star marking the herdsman’s shoulder in Boötes, a star whose surface pulses gently in a rapid rhythm of brightening and dimming.
At a glance
| type | white star (class A) |
|---|---|
| distance from the Sun | 86.8 light-years (26.6 pc) |
| its light left it | 86.8 years ago |
| luminosity | 39.4 × the Sun |
| radius | 3.39 × the Sun |
| surface temperature | 7,850 K |
| constellation | Bootes (Herdsman) |
Read off the piece’s own catalogue, the same values it draws with.
About Seginus
Seginus is a white star of class A, wider than the Sun and far more luminous. It is a Delta Scuti variable: its outer layers pulse in and out in a matter of hours, changing its brightness by an amount too small for the eye to notice.
It marks the left shoulder of the herdsman, at one corner of the kite of Boötes. The origin of its name is uncertain.
What you see in the piece
In the piece Seginus is a steady white point at its real brightness; its pulsation is far too small to show at any scale the eye can see.
Questions
Is Seginus a variable star?
Yes, slightly. It is a Delta Scuti variable whose brightness changes by a small amount over a few hours.