Algol
Also known as β Per · HR 936
Algol is a spectroscopic binary star in the constellation Perseus, about 89.9 light-years from Earth.
Facts
| Type | Spectroscopic binary star (spectral type B8V) |
|---|---|
| Constellation | Perseus |
| Position (J2000) | 3h 08m 10s, +40° 57′ |
| Distance | 89.9 light-years (its light set off about 89.9 years ago) |
| Brightness | magnitude 2.12 (smaller is brighter; the faintest stars the eye sees are about 6) |
| Size on the sky | 0′ (the full Moon is about 31′) |
| Studied in | 1,272 scientific papers (SIMBAD) |
When and how to see it
Algol is highest in the sky at midnight in November. From India (about 20° N) it climbs to about 69° above the horizon; from 50° N, to about 81°. To see it you need the naked eye, even from a town.
Heights are worked out for India and for 50° N. Set your location in Settings to see them for where you are.
For tonight's best time from your own town, the darkness and the Moon, open it on the map and see its "Tonight from your location" card.
More in Perseus
- Alpha Persei Cluster
- California Nebula
- Double Cluster
- Little Dumbbell Nebula (M76)
- M34 (NGC 1039)
- NGC 1277
- Perseus A (NGC 1275)
- Perseus Cluster
Everything in Perseus · All 88 constellations · All sky objects
Data: SIMBAD (CDS, Strasbourg; the site's weekly copy) · Data sources & credits