Star profile
Sigma Cygni
Hot blue starWhat is Sigma Cygni
Sigma Cygni is a blue supergiant almost three thousand light-years away, embedded in the Cygnus OB4 association. Its atmosphere is chemically strange: abnormally rich in helium, nitrogen, calcium, cerium and europium, depleted in carbon and aluminium. Corrected for the light absorbed by interstellar dust, it shines more than fifty thousand times brighter than the Sun. Internal pulsations with a 1.59-hour period stir its spectral lines while leaving its brightness untouched.
Where it is and when to see it
Sigma Cygni lies in the northern celestial hemisphere. It is visible to the naked eye under a dark sky. Its best month of the year is September: the Sun sits at the opposite point of the sky and the star culminates around midnight. How high it climbs above the horizon depends on the latitude you watch from.
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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 Sigma Cygni
- Constellation
- Cygnus
- Apparent magnitude
- 4.22
- Distance
- 2886.7 light years
- Coordinates (J2000)
- RA 319.354° · Dec 39.395°
- Catalogue
- HIP 105102 · HD 202850
A symbolic commemorative gift: neither the signature nor the chosen name implies ownership of the star or recognition by the IAU.
Other stars in Cygnus
Cygnus has 137 stars in Stelvia's catalogue. Here are a few of them.
- DenebAlpha Cygni1.25
- SadrGamma Cygni2.23
- AljanahEpsilon Cygni2.48
- Rho Cygni3.98
- 41 Cygni4.01
- 52 Cygni4.22
- Pi 2 Cygni4.23
- 33 Cygni4.28