Perseus
Perseus is at the side of Andromeda along the Milky Way. They are high in the sky
in the winter. If you use binoculars, you can see a pair of open star clusters
(NGC 869 & NGC 884) close together in the midst of the Milky Way in Perseus. This double cluster is
known as the Sword Handle.
Another interesting object in Perseus is the variable star Algol. Every
2.7 days, Algol becomes fainter for a period of five hours. It goes from its normal magnitude of
2.1 down to magnitude 3.3 and back to magnitude 2.1 again. This happens when
Algol is eclipsed by its companion star.
| Telescopic Objects | Main Stars | ||||||
| Object | Magnitude | Comments | Name | Magnitude | Distance L/Y | Comments | |
| NGC 869 | 4.3 | Open cluster | a Mirphak | 1.8 | 620 | ||
| NGC 884 | 4.4 | Open cluster | b Algol | 2.4 - 2.9 | 95 | Eclipsing binary | |
| M34 | 5.2 | Open cluster | z Atik | 2.8 | 1,108 | ||
| NGC 1245 | 8.4 | Open cluster | g | 2.8 | 110 | ||
| e | 2.9 | 678 | |||||
| Variable Stars | Range | Period | Multiple Stars | ||||
| b Algol | 2.1 - 3.3 | 2.7 days | Name | Magnitude / Separation" | |||
| g | 2.8 & 10.6 / 57" | ||||||
| e | 2.9 & 8.1 / 8.8" | ||||||
| h | 3.3 & 8,5 / 28.3" | Good target for binoculars | |||||
| z Atik | 2.8 & 9.5 / 12.9" | Two more stars in the same field | |||||