R Coronae Australis

R Coronae Australis
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Corona Australis
Right ascension 19h 01m 53.6503s[1]
Declination −36° 57 07.87[1]
Apparent magnitude (V) +11.91
Characteristics
Spectral type B5IIIpe[1]
Variable type irregular[2]
Astrometry
Radial velocity (Rv)-36 km/s
Proper motion (μ) RA: -28.30 mas/yr
Dec.: 20.57 mas/yr
Parallax (π)40.93 ± 27.95 mas
Distanceapprox. 80 ly
(approx. 20 pc)
Details
Other designations
AAVSO 1855-37A, CD-37 13027 HIP 93449

R Coronae Australis (R CrA) is variable star in the constellation Corona Australis.[1] It has varied between magnitudes 10 and 14.36.[2] A small reflection/emission nebula NGC 6729 extends from star towards SE.

This star is moving toward the Solar System with a radial velocity of 36 km s−1. In roughly 222,000 years, this system may approach within 1.77 light-years (0.54 parsecs) of the Sun. However, this estimate has a considerable margin of error, so the actual distance remains uncertain.[3]

A colour photo of the R Coronae Australis region in the southern Milky Way.

References

  1. 1.0 1.1 1.2 1.3 "R Coronae Australis". SIMBAD Astronomical Database. Centre de Données astronomiques de Strasbourg. Retrieved 29 June 2014.
  2. 2.0 2.1 BSJ (14 June 2010). "R Coronae Australis". AAVSO Website. American Association of Variable Star Observers. Retrieved 29 June 2014.
  3. Dybczyński, P. A. (April 2006), "Simulating observable comets. III. Real stellar perturbers of the Oort cloud and their output", Astronomy and Astrophysics 449 (3): 1233–1242, Bibcode:2006A&A...449.1233D, doi:10.1051/0004-6361:20054284