Observation data Epoch J2000.0 Equinox J2000.0 ( ICRS) | |
---|---|
Constellation | Crater |
Right ascension | 11h 11m 39.48783s [1] |
Declination | −22° 49′ 33.0593″ [1] |
Apparent magnitude (V) | 4.46 [2] (4.61 + 13.40) [3] |
Characteristics | |
Spectral type | A2 III [3] + DA1.4 [3] |
U−B color index | +0.05 [2] |
B−V color index | +0.02 [2] |
Astrometry | |
Radial velocity (Rv) | +5.6±0.5 [4] km/s |
Proper motion (μ) |
RA: + 5.220 ± 0.546
[5]
mas/
yr Dec.: −103.457 ± 0.483 [5] mas/ yr |
Parallax (π) | 11.0358 ± 0.2918 mas [5] |
Distance | 296 ± 8
ly (91 ± 2 pc) |
Absolute magnitude (MV) | −0.62 [6] + 8.19 [3] |
Details | |
Luminosity | 147 [7] L☉ |
Surface gravity (log g) | 3.5 [8] cgs |
Temperature | 8,830 [7] K |
Rotational velocity (v sin i) | 49 [9] km/s |
β Crt B | |
Mass | 0.43 [10] M☉ |
Radius | 0.027 [3] R☉ |
Surface gravity (log g) | 7.40 [11] cgs |
Temperature | 36,885 [11] K |
Other designations | |
Database references | |
SIMBAD | data |
Beta Crateris, Latinized from β Crateris, is a binary star [3] system in the southern constellation of Crater. It is visible to the naked eye with an apparent visual magnitude of 4.46. [2] Based upon an annual parallax shift of 9.59 mas as seen from Earth, it is located around 340 light years from the Sun.
This is an astrometric binary [13] star system with an orbital period of 6.0 years and a projected separation of 8.3 AU. The orbit has an estimated semimajor axis of 9.3 AU. [3] The primary, component A, is listed as an A-type giant star with a stellar classification of A2 III. [3] [13] [10] However, Houk and Smith-Moore (1988) give a main sequence classification of A1 V, [14] while Abt and Morrell (1995) list it as a subgiant star with a class of A2 IV. [15] The spectrum shows enhanced barium, possibly as a result of a previous mass transfer event. [8]
The companion, component B, is a white dwarf [10] of class DA with an effective temperature of 36,885 K that has been cooling down for around four million years. [11] It has an unusually low mass, 43% that of the Sun, suggesting that the white dwarf progenitor may have transferred matter to its companion. Alternative scenarios require either the evolution of a triple star system, or a binary system with highly eccentric orbit resulting in grazing interactions. [3] The dwarf is a source of X-ray emission. [16]
This star was one of the set assigned by the 16th century astronomer Al Tizini [17] to Al Sharāsīf (ألشراسيف), the Ribs (of Hydra), which included the stars from β Crateris westward through κ Hydrae. [18] [19]
According to the catalogue of stars in the Technical Memorandum 33-507 - A Reduced Star Catalog Containing 537 Named Stars, Al Sharāsīf were the title for two stars : β Crateris as Al Sharasīf II and κ Hydrae as Al Sharasīf I. [20]
In Chinese, 翼宿 (Yì Sù), meaning Wings (asterism), refers to an asterism consisting of β Crateris, α Crateris, γ Crateris, ζ Crateris, λ Crateris, ν Hydrae, η Crateris, δ Crateris, ι Crateris, κ Crateris, ε Crateris, HD 95808, HD 93833, θ Crateris, HD 102574, HD 100219, HD 99922, HD 100307, HD 96819, χ1 Hydrae, HD 102620 and HD 103462. [21] Consequently, β Crateris itself is known as 翼宿十六 (Yì Sù shíliù, English: the Sixteenth Star of Wings.) [22] [23]
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cite web}}
: CS1 maint: postscript (
link)
Observation data Epoch J2000.0 Equinox J2000.0 ( ICRS) | |
---|---|
Constellation | Crater |
Right ascension | 11h 11m 39.48783s [1] |
Declination | −22° 49′ 33.0593″ [1] |
Apparent magnitude (V) | 4.46 [2] (4.61 + 13.40) [3] |
Characteristics | |
Spectral type | A2 III [3] + DA1.4 [3] |
U−B color index | +0.05 [2] |
B−V color index | +0.02 [2] |
Astrometry | |
Radial velocity (Rv) | +5.6±0.5 [4] km/s |
Proper motion (μ) |
RA: + 5.220 ± 0.546
[5]
mas/
yr Dec.: −103.457 ± 0.483 [5] mas/ yr |
Parallax (π) | 11.0358 ± 0.2918 mas [5] |
Distance | 296 ± 8
ly (91 ± 2 pc) |
Absolute magnitude (MV) | −0.62 [6] + 8.19 [3] |
Details | |
Luminosity | 147 [7] L☉ |
Surface gravity (log g) | 3.5 [8] cgs |
Temperature | 8,830 [7] K |
Rotational velocity (v sin i) | 49 [9] km/s |
β Crt B | |
Mass | 0.43 [10] M☉ |
Radius | 0.027 [3] R☉ |
Surface gravity (log g) | 7.40 [11] cgs |
Temperature | 36,885 [11] K |
Other designations | |
Database references | |
SIMBAD | data |
Beta Crateris, Latinized from β Crateris, is a binary star [3] system in the southern constellation of Crater. It is visible to the naked eye with an apparent visual magnitude of 4.46. [2] Based upon an annual parallax shift of 9.59 mas as seen from Earth, it is located around 340 light years from the Sun.
This is an astrometric binary [13] star system with an orbital period of 6.0 years and a projected separation of 8.3 AU. The orbit has an estimated semimajor axis of 9.3 AU. [3] The primary, component A, is listed as an A-type giant star with a stellar classification of A2 III. [3] [13] [10] However, Houk and Smith-Moore (1988) give a main sequence classification of A1 V, [14] while Abt and Morrell (1995) list it as a subgiant star with a class of A2 IV. [15] The spectrum shows enhanced barium, possibly as a result of a previous mass transfer event. [8]
The companion, component B, is a white dwarf [10] of class DA with an effective temperature of 36,885 K that has been cooling down for around four million years. [11] It has an unusually low mass, 43% that of the Sun, suggesting that the white dwarf progenitor may have transferred matter to its companion. Alternative scenarios require either the evolution of a triple star system, or a binary system with highly eccentric orbit resulting in grazing interactions. [3] The dwarf is a source of X-ray emission. [16]
This star was one of the set assigned by the 16th century astronomer Al Tizini [17] to Al Sharāsīf (ألشراسيف), the Ribs (of Hydra), which included the stars from β Crateris westward through κ Hydrae. [18] [19]
According to the catalogue of stars in the Technical Memorandum 33-507 - A Reduced Star Catalog Containing 537 Named Stars, Al Sharāsīf were the title for two stars : β Crateris as Al Sharasīf II and κ Hydrae as Al Sharasīf I. [20]
In Chinese, 翼宿 (Yì Sù), meaning Wings (asterism), refers to an asterism consisting of β Crateris, α Crateris, γ Crateris, ζ Crateris, λ Crateris, ν Hydrae, η Crateris, δ Crateris, ι Crateris, κ Crateris, ε Crateris, HD 95808, HD 93833, θ Crateris, HD 102574, HD 100219, HD 99922, HD 100307, HD 96819, χ1 Hydrae, HD 102620 and HD 103462. [21] Consequently, β Crateris itself is known as 翼宿十六 (Yì Sù shíliù, English: the Sixteenth Star of Wings.) [22] [23]
{{
cite web}}
: CS1 maint: postscript (
link)