Eta Canis Majoris

η Canis Majoris
Location of η Canis Majoris (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Canis Major
Right ascension 07h 24m 05.70228s[1]
Declination –29° 18′ 11.1798″[1]
Apparent magnitude (V) 2.450[2]
Characteristics
Spectral type B5 Ia[3]
U−B color index −0.708[2]
B−V color index −0.087[2]
Variable type α Cyg[4]
Astrometry
Radial velocity (Rv)41.1[5] km/s
Proper motion (μ) RA: −4.14[1] mas/yr
Dec.: 5.81[1] mas/yr
Parallax (π)1.64 ± 0.40 mas[1]
Distanceapprox. 2,000 ly
(approx. 600 pc)
Absolute magnitude (MV)−7.0[6]
Details
Mass18.19[7] M☉
Radius54[8] R☉
Luminosity135,000 - 174,000[8] L☉
Surface gravity (log g)2.00[8] cgs
Temperature15,000 - 16,000[8] K
Rotational velocity (v sin i)40[8] km/s
Age8.3[9] Myr
Other designations
Aludra, 31 Canis Majoris, CD−29°4328, FK5 283, HD 58350, HIP 35904, HR 2827, SAO 173651
Database references
SIMBADdata

Eta Canis Majoris (η Canis Majoris, abbreviated Eta CMa, η CMa), also named Aludra /əˈluːdrə, əˈljuːdrə/,[10] is a star in the constellation of Canis Major. Since 1943, the spectrum of this star has served as one of the stable anchor points by which other stars are classified.[11]

  1. ^ a b c d e Cite error: The named reference aaa474_2_653 was invoked but never defined (see the help page).
  2. ^ a b c Cite error: The named reference apj156_853 was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference aaa521 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference Kazarovets was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference scfs was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference mnras189_601 was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference kervella2022 was invoked but never defined (see the help page).
  8. ^ a b c d e Cite error: The named reference haucke2018 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference tetzlaff2011 was invoked but never defined (see the help page).
  10. ^ "IAU Catalog of Star Names". Retrieved 28 July 2016.
  11. ^ Cite error: The named reference baas25_1319 was invoked but never defined (see the help page).