Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Cassiopeia |
Right ascension | 23h 48m 50.171s [1] |
Declination | +62° 12′ 52.26″ [1] |
Apparent magnitude (V) | +5.43 [2] (5.34 - 5.45 [3] ) |
Characteristics | |
Spectral type | A2.5 Ia+ [4] |
U−B color index | −0.02 [2] |
B−V color index | +0.67 [2] |
Variable type | α Cyg [3] |
Astrometry | |
Proper motion (μ) | RA: −3.57±0.35 [1] mas/yr Dec.: −1.57±0.33 [1] mas/yr |
Parallax (π) | 0.53 ± 0.37 mas [1] |
Distance | 2,510 [5] pc |
Absolute magnitude (MV) | −8.30 [6] |
Details | |
Mass | 22.0 [6] M☉ |
Radius | 193 [6] R☉ |
Luminosity | 200,000 [7] L☉ |
Surface gravity (log g) | 1.59 [8] cgs |
Temperature | 10,023±227 [8] K |
Metallicity [Fe/H] | 0.29 [8] dex |
Rotational velocity (v sin i) | 50 [6] km/s |
Other designations | |
Database references | |
SIMBAD | data |
6 Cassiopeiae (6 Cas) is a white hypergiant in the constellation Cassiopeia, and a small-amplitude variable star.
6 Cassiopeiae A is a white A2.5 type hypergiant. It is about 25 times as massive as the Sun and 200,000 times as luminous. The star is slightly and erratically variable, an Alpha Cygni variable. Not all sources consider 6 Cas to be a hypergiant. It is thought that the "+" in an early A3 Ia+ spectral classification referred to indications of additional spectral features from a possible companion rather than the more modern indication of a hypergiant luminosity class. However, later publications have given more conventional hypergiant spectral types such as B9Ia+ and A3Ia+. [9]
6 Cas A has a number of close companions, most notably an 8th magnitude O class bright giant at only 1.5″ . Its spectral type is O9.75 and its absolute magnitude is −5.8. [12] Both are considered to be members of the Cassiopeia OB5 stellar association at a distance of around 8,000 light-years, [13] along with several other nearby stars. [14] Gaia parallaxes of the nearby stars suggest a mean distance to the association of about 9,000 light years. [14]
6 Cas A is an α Cyg variable, pulsating erratically between 5.34 and 5.45. The strongest period detected in one study was 37 days. [10] It has the variable star designation V566 Cassiopeiae. [3]
Rho Cassiopeiae is a yellow hypergiant star in the constellation Cassiopeia. It is about 8,150 light-years (2,500 pc) from Earth, yet can still be seen by the naked eye as it is over 300,000 times brighter than the Sun. On average it has an absolute magnitude of −9.5, making it visually one of the most luminous stars known. Its diameter measures between 636 and 981 times that of the Sun, approximately 1,125,000,000 kilometers, or almost four times the size of Earth's orbit.
CS Camelopardalis is a binary star in reflection nebula VdB 14, in the constellation Camelopardalis.
Alpha Cygni variables are variable stars which exhibit non-radial pulsations, meaning that some portions of the stellar surface are contracting at the same time other parts expand. They are supergiant stars of spectral types B or A. Variations in brightness on the order of 0.1 magnitudes are associated with the pulsations, which often seem irregular, due to beating of multiple pulsation periods. The pulsations typically have periods of several days to several weeks.
V382 Carinae, also known as x Carinae, is a yellow hypergiant in the constellation Carina. It is a G-type star with a mean apparent magnitude of +3.93, and a variable star of low amplitude.
Kappa Cassiopeiae is a star in the constellation Cassiopeia.
Omicron1 Centauri is a star in the constellation Centaurus. It is approximately 10,000 light years from Earth.
Zeta Cephei is a red supergiant star, located about 1000 light-years away in the constellation of Cepheus. Zeta Cephei marks the left shoulder of Cepheus, the King of Ethiopia. It is one of the fundamental stars of the MK spectral sequence, defined as type K1.5 Ib.
V Aquilae is a carbon star and semiregular variable star in the constellation Aquila. It has an apparent magnitude which varies between 6.6 and 8.4 and is located around 400 parsecs (1,300 ly) away.
V810 Centauri is a double star consisting of a yellow hypergiant primary and blue giant secondary. It is a small amplitude variable star, entirely due to the supergiant primary which is visually over three magnitudes brighter than the secondary. It is the MK spectral standard for class G0 0-Ia.
TZ Cassiopeiae(TZ Cas, HIP 117763, SAO 20912) is a variable star in the constellation Cassiopeia with an apparent magnitude of around +9 to +10. It is approximately 8,400 light-years away from Earth. The star is a red supergiant star with a spectral type of M3 and a temperature around 3,600 K.
HD 168607 is a blue hypergiant and luminous blue variable (LBV) star located in the constellation of Sagittarius, easy to see with amateur telescopes. It forms a pair with HD 168625, also a blue hypergiant and possible luminous blue variable, that can be seen at the south-east of M17, the Omega Nebula.
55 Cygni is a blue supergiant star in the constellation Cygnus. It is thought to be a member of the Cygnus OB7 stellar association at about 2,700 light years.
9 Cephei, also known as V337 Cephei, is a variable star in the constellation Cepheus.
PZ Cassiopeiae is a red supergiant star located in the constellation of Cassiopeia, and a semi-regular variable star.
13 Monocerotis is a class A0 Ib star in the constellation Monoceros. Its apparent magnitude is 4.5 and it is approximately 780 parsecs (2,500 ly) away.
Sigma Ophiuchi, Latinized from σ Ophiuchi, is a single, orange-hued star in the equatorial constellation Ophiuchus. Its apparent visual magnitude is 4.31, which is bright enough to be faintly visible to the naked eye. The annual parallax shift of 3.62 mas as seen from Earth provides a distance estimate of roughly 900 light years. It is moving closer to the Sun with a radial velocity of −28 km/s.
9 Persei is a single variable star in the northern constellation Perseus, located around 4,300 light years away from the Sun. It has the Bayer designation i Persei; 9 Persei is the Flamsteed designation. This body is visible to the naked eye as a faint, white-hued star with an apparent visual magnitude of about 5.2. It is moving closer to the Sun with a heliocentric radial velocity of −15.2 km/s. The star is a member of the Perseus OB1 association of co-moving stars.
10 Persei is a blue supergiant star in the constellation Perseus. Its apparent magnitude is 6.26 although it is slightly variable.
3 Geminorum is a blue supergiant star in the constellation Gemini. It is a small amplitude pulsating variable and a close double star, with a mean combined apparent visual magnitude of about 5.7.
S Cassiopeiae is a Mira variable and S-type star in the constellation Cassiopeia. It is an unusually cool star, rapidly losing mass and surrounded by dense gas and dust producing masers.