Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Scorpius |
Right ascension | 17h 11m 17.01945s [1] |
Declination | −32° 19′ 30.7140″ [1] |
Apparent magnitude (V) | 6.5 - 9.6 [2] |
Characteristics | |
Spectral type | M4-5 Ia-Iab [3] |
B−V color index | +2.57 [4] |
Variable type | SRc [3] |
Astrometry | |
Radial velocity (Rv) | −13.40±2.4 [5] km/s |
Proper motion (μ) | RA: −2.322±0.115 [1] mas/yr Dec.: −2.610±0.068 [1] mas/yr |
Parallax (π) | 0.5632 ± 0.0799 mas [1] |
Distance | 7,400±620 ly (2,260±190 [6] pc) |
Absolute magnitude (MV) | −5.8 [7] |
Details | |
Mass | 20 [8] M☉ |
Radius | 1,411±124 [4] R☉ |
Luminosity | 329,000±86,000 [4] L☉ |
Surface gravity (log g) | −0.5 [4] cgs |
Temperature | 3,682 [4] K |
Other designations | |
Database references | |
SIMBAD | data |
AH Scorpii (abbreviated to AH Sco) is a red supergiant variable star located in the constellation Scorpius. It is one of the largest stars known by radius and is also one of the most luminous red supergiant stars in the Milky Way.
The distance of AH Scorpii is considered to be uncertain. VLBI measurements of the masers have provided an accurate distance of 2,260 parsecs based on observation of SiO, H2O, and OH masers in its oxygen-rich circumstellar material. The masers were observed to be approaching the star at 13 km/s, indicating overall contraction at around phase 0.55 of the visual variations. [6]
AH Scorpii is a dust-enshrouded red supergiant [10] and is classified as a semiregular variable star with a main period of 714 days. The total visual magnitude range is 6.5 - 9.6. [2] No long secondary periods have been detected. [11] Modelling of AH Scorpii near maximum light has determined an effective temperature of 3,682±190 K and a luminosity of 330,000±86,000 L☉. A radius of 1,411±124 R☉ was determined from an angular diameter of 5.81±0.15 mas and the given distance of 2.26±0.19 kpc. [4] Its angular diameter was re-measured at 5.05±0.5 mas in 2023. [12]
X Sagittarii is a variable star and candidate binary star system in the southern constellation of Sagittarius, near the western constellation boundary with Ophiuchus. It has a yellow-white hue and is visible to the naked eye with an apparent visual magnitude that fluctuates around 4.54. The star is located at a distance of approximately 950 light years from the Sun based on parallax, and is drifting closer with a radial velocity of −10 km/s. The star has an absolute magnitude of around −2.85.
Xi Scorpii is part of a quintuple star system in the constellation Scorpius. It was assigned this designation by Bayer, although Ptolemy had catalogued the star in Libra. Flamsteed assigned it the designation 51 Librae, but this has fallen out of use since modern constellation boundaries assign the star to Scorpius.
Rho Scorpii is a double star in the constellation of Scorpius. It has an apparent visual magnitude of +3.87, which is bright enough to be seen with the naked eye. Based upon parallax measurements, it is located approximately 472 light years from the Sun. At that distance, the visual magnitude of the system is reduced by 0.07 due to extinction from interstellar dust. It is a member of the Upper Scorpius OB association.
KW Sagittarii is a red supergiant star, located approximately 2,160 parsecs away from the Sun in the direction of the constellation Sagittarius. It is one of the largest known stars, with a diameter about 1,000 times larger than the Sun. If placed at the center of the Solar System, the star's surface would engulf Mars, coming close to Jupiter's orbit.
V354 Cephei is a red supergiant star located within the Milky Way. It is an irregular variable located over 13,000 light-years away from the Sun. It has an estimated radius of 1,139 solar radii. If it were placed in the center of the Solar System, it would extend to between the orbits of Mars and Jupiter.
NO Aurigae is a pulsating variable star in the constellation Auriga. It is an unusually-luminous asymptotic giant branch star about 3,500 light years away.
Zeta1 Scorpii is a B-type hypergiant star in the constellation of Scorpius. It has an apparent visual magnitude which varies between 4.66 and 4.86. It is a member of the Scorpius OB1 association, and potentially of the open star cluster NGC 6231, also known as the "Northern jewel box" cluster. Around 36 times as massive as the Sun, it is also one of the most luminous stars known in the Galaxy, with an estimated bolometric luminosity of around 850,000 times that of the Sun and a radius 103 times that of the Sun.
Zeta2 Scorpii is a K-type orange giant star in the constellation of Scorpius. It has an apparent visual magnitude which varies between 3.59 and 3.65, and is located near the blue-white supergiant star ζ1 Scorpii in Earth's sky. In astronomical terms, ζ2 is much closer to the Sun and unrelated to ζ1 except for line-of sight co-incidence. ζ1 is about 6,000 light-years away and probably an outlying member of open star cluster NGC 6231, whereas ζ2 is a mere 135 light-years distant and thus much less luminous in real terms. ζ2 can also be distinguished from its optical partner, ζ1, because of its orangish colour especially in long-exposure astrophotographs.
V381 Cephei is a triple star system in the northern constellation of Cepheus. Its apparent magnitude is slightly variable between 5.5 and 5.7.
V602 Carinae is a red supergiant and variable star of spectral type M3 in the constellation Carina. It is considered to be one of largest known stars, being around 1,000 times larger than the Sun.
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.
V424 Lacertae is a red supergiant variable star in the constellation Lacerta. It is a member of the Lacerta OB1 stellar association.
PZ Cassiopeiae is a red supergiant star located in the constellation of Cassiopeia, and a semi-regular variable star.
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.
V1073 Scorpii is a variable star in the constellation Scorpius. It has a non-Greek Bayer designation of k Scorpii. The star has a blue-white hue and is visible to the naked eye with an apparent visual magnitude that fluctuates around +4.87. Parallax measurements yield a distance estimate of approximately 2,920 ly (896 pc) from the Sun, and it is drifting further away with a radial velocity of +7 km/s. It has an absolute magnitude of −6.8
UY Scuti (BD-12°5055) is a red supergiant star, located 5,900 light-years away in the constellation Scutum. It is also a pulsating variable star, with a maximum brightness of magnitude 8.29 and a minimum of magnitude 10.56, which is too dim for naked-eye visibility. It is considered to be one of the largest known stars, with a radius estimated at 909 solar radii, thus a volume of 750 million times that of the Sun. This estimate implies if it were placed at the center of the Solar System, its photosphere would extend past the orbit of Mars or even the asteroid belt.
V915 Scorpii is a hypergiant and semiregular variable star, located 1,718 parsecs (5,600 ly) away in the constellation Scorpius. Its apparent magnitude varies between 6.22 and 6.64, being heavily diminshed by 2.93 magnitudes due to interstellar extinction.
CK Carinae is a variable star in the constellation Carina, the keel of Argo Navis. It is a member of the star association Carina OB1-D, at a distance of around 2,300 parsecs or 7,500 light years.
BO Carinae, also known as HD 93420, is an irregular variable star in the constellation Carina.