Cassiopeia constellation
Cassiopeia is one of the 88 constellations, and it represents the queen. It is highest in the sky at midnight around 7 October, and its whole figure rises above the horizon from 90°N to 26°S.
Cassiopeia at a glance
- Represents
- the queen
- Highest at midnight
- 7 October
- Highest at 9 pm
- 20 November
- Seen whole from
- 90°N to 26°S
- Brightest star
- Cih
- Stars in the figure
- 5 stars
- Origin
- Ptolemy's list, 2nd century
When to see Cassiopeia
Cassiopeia is highest in the sky at midnight around 7 October and at 9 pm around 20 November. Each month it is highest about two hours earlier than the month before.
The times are local solar time. Clocks on summer time or daylight saving time read about one hour later.
| Date | Highest at |
|---|---|
| 15 January | 5:20 pm |
| 15 February | 3:20 pm |
| 15 March | 1:30 pm |
| 15 April | 11:30 am |
| 15 May | 9:30 am |
| 15 June | 7:30 am |
| 15 July | 5:30 am |
| 15 August | 3:30 am |
| 15 September | 1:20 am |
| 15 October | 11:20 pm |
| 15 November | 9:20 pm |
| 15 December | 7:20 pm |
Where to look for Cassiopeia
From the northern hemisphere
From 40°N, Cassiopeia never sets. It circles the pole and is highest around midnight on 7 October, 69° above the northern horizon.
From the southern hemisphere
From 35°S, Cassiopeia never rises. You need to be north of 33°S to see any of it.
Brightest stars in Cassiopeia
Cassiopeia in myth and history
In Greek myth, Cassiopeia was the queen of Aethiopia, the wife of King Cepheus and the mother of Andromeda. Her boast that she was more beautiful than the sea nymphs angered the sea god Poseidon, who sent the sea monster Cetus.
Cassiopeia is one of the 48 constellations that the astronomer Ptolemy listed in the 2nd century.
Constellations next to Cassiopeia
Find Cassiopeia in your sky
Questions about Cassiopeia
Cassiopeia is highest in the sky at midnight around 7 October and at 9 pm around 20 November. The weeks around those dates are the best time to look.
The whole figure of Cassiopeia rises above the horizon from 90°N to 26°S, and at least part of it rises from 90°N to 33°S.
Cih is the brightest star in Cassiopeia, at magnitude 2.15.
Cassiopeia represents the queen. Cassiopeia is one of the 48 constellations that the astronomer Ptolemy listed in the 2nd century.