Epsilon Crucis

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Epsilon Crucis
Ctx crux.gif
Crux, showing Epsilon Crucis in relation to the other main stars
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Crux
Right ascension 12h 21m 21.6s
Declination −60° 24′ 4″
Apparent magnitude (V) 3.56
Characteristics
Spectral type K3III
U−B color index 1.63
B−V color index 1.42
Astrometry
Radial velocity (Rv) −4.6 km/s
Proper motion (μ) RA: −171.06 mas/yr
Dec.: 91.83 mas/yr
Parallax (π) 14.30 ± -.56 mas
Distance 228 ± −9 ly
(70 ± −3 pc)
Absolute magnitude (MV) −0.63 ± 0.09[1]
Details
Mass 1.42 ± 0.22[1] M
Radius 32.9 ± 2.5[1] R
Surface gravity (log g) 1.52 ± 0.11[1] cgs
Temperature 4,148[1] K
Metallicity [Fe/H] −0.10[1] dex
Age 2.83 ± 1.20[1] Gyr
Other designations
HD 107446, HR 4700, SAO 251862, FK5 2989, NSV 5568, CD -59°4221 , HIP 60260

Epsilon Crucis (ε Cru, ε Crucis) is a Class K3III, fourth-magnitude star in the constellation Crux. It is sometimes called Intrometida (intrusive) in Portuguese.[2] This star is an orange giant, located about 228 light-years from Earth.

The bright blue star on the right centre of this image is Epsilon Crucis. The colours used in this image represent specific wavelengths of infrared light. Blue represents light emitted at 3.4 and 4.6 micrometres.

Modern legacy[edit]

ε Cru is represented on the flags of Australia and Papua New Guinea, as one of five stars which comprise the Southern Cross. It is also featured in the flag of Brazil, along with 26 other stars, each of which represents a state. ε Cru represents the State of Espírito Santo.[3]

References[edit]

  1. ^ a b c d e f g da Silva, L. et al. (November 2006), "Basic physical parameters of a selected sample of evolved stars", Astronomy and Astrophysics 458 (2): 609–623, arXiv:astro-ph/0608160, Bibcode:2006A&A...458..609D, doi:10.1051/0004-6361:20065105 
  2. ^ da Silva Oliveira, R., "Crux Australis: o Cruzeiro do Sul", Artigos: Planetario Movel Inflavel AsterDomus.
  3. ^ "Astronomy of the Brazilian Flag". FOTW Flags Of The World website. 

External links[edit]