Rho2 Arietis

From Wikipedia, the free encyclopedia
(Redirected from 45 Arietis)
Jump to navigation Jump to search

Template:Short description

Template:Other stars by Bayer designation

ρ2 Arietis
Template:Location mark
Location of ρ2 Arietis (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Aries[1]
Right ascension Template:RA[2]
Declination Template:DEC[2]
Apparent magnitude (V) 5.93[3] (5.45–6.01)[4]
Characteristics
Evolutionary stage AGB[5][6]
Spectral type M6 III[7]
U−B Template:Engvar +1.12[3]
B−V Template:Engvar +1.51[3]
R−I Template:Engvar +2.17[8]
Variable type SRb[4]
Astrometry
Radial velocity (Rv)+46.0[9] km/s
Proper motion (μ) RA: −7.78[2] mas/yr
Dec.: −14.98[2] mas/yr
Parallax (π)9.28±0.30 mas[2]
DistanceTemplate:Rnd ± Template:Rnd ly
(Template:Rnd ± Template:Rnd pc)
Absolute magnitude (MV)+0.60[1]
Details
Mass1.21[6] Template:Solar mass
RadiusScript error: No such module "val".[6] Template:Solar radius
Luminosity1,390[6] Template:Solar luminosity
Surface gravity (log g)0.5[10] cgs
Temperature3,400[10] K
Metallicity [Fe/H]–0.25[6] dex
Rotation<909[6] days
Rotational velocity (v sin i)Script error: No such module "val".[10] km/s
Metallicity [Fe/H]{{{metal_fe2}}} dex
Other designations
Template:Odlist[11]
Database references
SIMBADdata

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

Rho2 Arietis is an M-type red giant star in the northern constellation of Aries. Its name is a Bayer designation that is Latinized from ρ2 Arietis, and abbreviated Rho2 Ari or ρ2 Ari. The brightness of this star varies from magnitude 5.45 to 6.01,[12] making it faintly visible to the naked eye under good observing conditions. With an annual parallax shift of Script error: No such module "val".,[2] it is approximately Script error: No such module "convert". distant from the Earth. It is drifting further away from the Sun with a radial velocity of +46 km/s.[9]

File:RZAriLightCurve.png
A visual band light curve for Rho2 Arietis, plotted from data presented in Tabur et al. (2009)[13]

Rho2 Arietis is classified as a semiregular variable star with periods of 49.9 and 54.8 days.[13] It has the variable star designation, RZ Arietis.[4]

This is a red giant star with a stellar classification of M6 III;[7] it is probably on the asymptotic giant branch, having exhausted its core helium.[5][6] It is predicted to have started its life with 1.5 times the mass of the Sun, and is now down to 1.2 times the Sun's mass. At its current evolutionary stage Rho2 Arietis has expanded to 108 times the Sun's radius. It is radiating 1,390 times the Sun's luminosity from its photosphere at an effective temperature of 3,400 K.[6]

This star possesses a strong magnetic field, one of the strongest for M-type giants. It also possesses a high lithium abundance, higher than expected from evolutionary models. The strong magnetic field, rapid rotation and unusual lithium abundance suggest this star may have engulfed a planet when it was on the red-giant branch.[6]

References

<templatestyles src="Reflist/styles.css" />

  1. ↑ a b Template:Cite XHIP
  2. ↑ a b c d e f Script error: No such module "citation/CS1".
  3. ↑ a b c Script error: No such module "citation/CS1".
  4. ↑ a b c Script error: No such module "citation/CS1". ID II/250.
  5. ↑ a b Script error: No such module "citation/CS1".
  6. ↑ a b c d e f g h i Script error: No such module "citation/CS1".
  7. ↑ a b Script error: No such module "citation/CS1".
  8. ↑ Script error: No such module "citation/CS1". ID V/50.
  9. ↑ a b Script error: No such module "citation/CS1".
  10. ↑ a b c Script error: No such module "citation/CS1".
  11. ↑ Script error: No such module "citation/CS1".
  12. ↑ Script error: No such module "citation/CS1".
  13. ↑ a b Script error: No such module "citation/CS1".

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

Template:Sky Template:Stars of Aries

Retrieved from "http://debianws.lexgopc.com/wiki143/index.php?title=Rho2_Arietis&oldid=7104085"