Star profile
31 Persei
Hot blue starWhat is 31 Persei
31 Persei shines blue-white more than five hundred and sixty light-years away, within a young, hot Perseus. It belongs to the Perseus OB2 association, a cluster of massive stars still bound by their shared birth in a gas cloud. Its B-type atmosphere is one of the few places in the sky where the human eye can sense, without knowing it, the true blue of the hottest stars.
Where it is and when to see it
31 Persei lies in the northern celestial hemisphere. It is visible to the naked eye under a dark sky. Its best month of the year is November, when it culminates around midnight.
- From London it never sets and culminates about 89° up.
- From New York it never sets and culminates about 81° up.
- From Sydney it culminates about 6° above the horizon.
It can be seen from anywhere north of 40° S.
It ranks no. 42 in brightness among the 99 stars of Perseus in our catalogue. To find it, start from Mirfak, the brightest: it lies about 1° away (a fist at arm's length covers about 10°).
The light you see today left it about 560 years ago.
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A public signature from a real person. The chosen name is a symbolic denomination within Stelvia, with no official standing or IAU recognition: the sky is not for sale and belongs to no one.
Astronomical data for 31 Persei
- Constellation
- Perseus
- Apparent magnitude
- 5.05
- Distance
- 560.5 light years
- Coordinates (J2000)
- RA 49.782° · Dec 50.095°
- Catalogue
- HIP 15444 · HD 20418
A symbolic commemorative gift: neither the signature nor the chosen name implies ownership of the star or recognition by the IAU.
Other stars in Perseus
Perseus has 99 stars in Stelvia's catalogue. Here are a few of them.
- MirfakAlpha Persei1.79
- AlgolBeta Persei2.09
- Zeta Persei2.84
- HIP 161474.99
- 4 Persei4.99
- HIP 152195.04
- 21 Persei5.10
- 42 Persei5.14