Alpha Sextantis

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Template:Short description

α Sextantis
Template:Location mark
Location of α Sextantis on the map (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Sextans
Right ascension Template:RA[1]
Declination Template:DEC[1]
Apparent magnitude (V) 4.49[2]
Characteristics
Spectral type A0 III[3]
U−B Template:Engvar −0.07[2]
B−V Template:Engvar −0.04[2]
Astrometry
Radial velocity (Rv)10.00[4] km/s
Proper motion (μ) RA: −25.83[1] mas/yr
Dec.: −4.25[1] mas/yr
Parallax (π)11.51±0.98 mas[1]
DistanceTemplate:Rnd ± Template:Rnd ly
(Template:Rnd ± Template:Rnd pc)
Absolute magnitude (MV)Template:Val[5]
Details
MassTemplate:Val[6] Template:Solar mass
Radius3.07[6] Template:Solar radius
Luminosity90[6] Template:Solar luminosity
Surface gravity (log g)3.55[7] cgs
Temperature9,984[8] K
Metallicity [Fe/H]Template:Val[7] dex
Rotational velocity (v sin i)21[9] km/s
Age385[6] Myr
Metallicity [Fe/H]{{{metal_fe2}}} dex
Other designations
α Sex, 15 Sextantis, BD+00°2615, FK5 2814, HD 87887, HIP 49641, HR 3981, SAO 137366.[10]
Database references
SIMBADdata

Script error: No such module "Check for unknown parameters".

Alpha Sextantis (α Sex, α Sextantis) is the brightest star in the equatorial constellation of Sextans.[11] It is visible to the naked eye on a dark night with an apparent visual magnitude of 4.49.[2] The distance to this star, as determined from parallax measurements,[1] is around 280 light years. This is considered an informal "equator star", as it lies less than a quarter of a degree south of the celestial equator. In 1900, it was 7 minutes of arc north of the equator. As a result of Earth's axial precession, it crossed over to the southern hemisphere in December 1923.[12]

The variability of Alpha Sextantis was discovered by Aven Magded Hamadamen and included in the International Variable Star Index.[13] The star undergoes pulsations with a period of 9.1 hours.[6]

This is an evolved A-type giant star with a stellar classification of A0 III.[3] It has around 2.5[6] times the mass of the Sun and three[6] times the Sun's radius. The abundance of elements is similar to that in the Sun.[7] It radiates 90 times the solar luminosity[6] from its outer atmosphere at an effective temperature of 9,984 K.[8] Alpha Sextantis is nearing the end of its life as a main-sequence star; it is around 385[6] million years old with a projected rotational velocity of 21 km/s.[9]

References

Template:Reflist

External links

Template:Stars of Sextans

  1. ↑ a b c d e f Cite error: Invalid <ref> tag; no text was provided for refs named vanLeeuwen2007
  2. ↑ a b c d Cite error: Invalid <ref> tag; no text was provided for refs named Mermilliod1986
  3. ↑ a b Cite error: Invalid <ref> tag; no text was provided for refs named Cowley1969
  4. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Gontcharov2006
  5. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Gerbaldi1999
  6. ↑ a b c d e f g h i Cite error: Invalid <ref> tag; no text was provided for refs named Bowman
  7. ↑ a b c Cite error: Invalid <ref> tag; no text was provided for refs named Pintado2003
  8. ↑ a b Cite error: Invalid <ref> tag; no text was provided for refs named Mcdonald2012
  9. ↑ a b Cite error: Invalid <ref> tag; no text was provided for refs named Royer2002
  10. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named SIMBAD
  11. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Darling
  12. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Kaler
  13. ↑ Script error: No such module "citation/CS1".
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