Star profile
4 Persei
Hot blue starWhat is 4 Persei
4 Persei is a hot blue B-type star 728 light-years away, set on the western edge of Perseus near the border with Andromeda. Its light pours from a surface so hot that most of its energy escapes as ultraviolet, invisible to human eyes. Perseus is a constellation crowded with young clusters —the Double Cluster lies not far— and 4 Persei fits in among that population of blue suns just a few tens of millions of years old.
Where it is and when to see it
4 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 87° up.
- From New York it never sets and culminates about 76° up.
- From Sydney it culminates about 2° above the horizon.
It can be seen from anywhere north of 36° S.
It ranks no. 39 in brightness among the 99 stars of Perseus in our catalogue. To find it, start from Mirfak, the brightest: it lies about 13° away (a fist at arm's length covers about 10°).
The light you see today left it about 730 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 4 Persei
- Constellation
- Perseus
- Apparent magnitude
- 4.99
- Distance
- 728.1 light years
- Coordinates (J2000)
- RA 30.575° · Dec 54.488°
- Catalogue
- HIP 9505 · HD 12303
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
- 32 Persei4.96
- 40 Persei4.97
- HIP 161474.99
- HIP 152195.04
- 31 Persei5.05