Star profile
40 Persei
Hot blue starWhat is 40 Persei
40 Persei is a hot blue B-type star sitting roughly 1,056 light-years away in the northern sky swept by Perseus. By distance and youth it belongs to the great stellar complex that anchors the Perseus arm of our galaxy, a region of massive star formation. Its intensely blue light set out when the Christian kingdoms of Iberia were only beginning their slow medieval reorganisation.
Where it is and when to see it
40 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 culminates about 72° above the horizon.
- From New York it culminates about 83° above the horizon.
- From Sydney it culminates about 22° above the horizon.
It can be seen from anywhere north of 56° S.
It ranks no. 38 in brightness among the 99 stars of Perseus in our catalogue. To find it, start from Mirfak, the brightest: it lies about 16° away (a fist at arm's length covers about 10°).
The light you see today left it about 1,100 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 40 Persei
- Constellation
- Perseus
- Apparent magnitude
- 4.97
- Distance
- 1055.7 light years
- Coordinates (J2000)
- RA 55.594° · Dec 33.965°
- Catalogue
- HIP 17313 · HD 22951
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
- 54 Persei4.93
- 24 Persei4.94
- 32 Persei4.96
- HIP 161474.99
- 4 Persei4.99