Eta Leonis

Nomenclature

With Regulus, γ Leonis (Algieba), and ζ Leonis (Adhafera), it formed the Arabic lunar mansion Al Jabhah, the forehead (of the lion). Some sources apply the name Al Jabhah to this star specifically, though the name Algieba for γ Leonis has the same etymology.

Properties

Eta Leonis is a blue supergiant with the stellar classification A0Ib. Since 1943, the spectrum of this star has served as one of the stable anchor points by which other stars are classified. Though its apparent magnitude is 3.5, making it a relatively dim star to the naked eye, it is nearly 20,000 times more luminous than the Sun, with an absolute magnitude of -5.60. The Hipparcos astrometric data has estimated the distance of Eta Leonis to be roughly 390 parsecs from Earth, or 1,270 light years away. It is believed to be in a blue loop phase.

Eta Leonis is apparently a multiple star system, but the number of components and their separation is uncertain.

References

References

1. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics.
2. (2012). "Quantitative spectroscopy of Galactic BA-type supergiants. I. Atmospheric parameters". Astronomy & Astrophysics.
3. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters.
4. (2006). "Quantitative spectroscopy of BA-type supergiants". Astronomy and Astrophysics.
5. (2013). "Elemental abundances of the supergiant stars σ Cygnus and η Leonis". New Astronomy.
6. (December 1993). "Anchor Points for the MK System of Spectral Classification". Bulletin of the American Astronomical Society.
7. (1996). "ICCD Speckle Observations of Binary Stars.XV.An Investigation of Lunar Occultation Systems". The Astronomical Journal.
8. (1899). "Star Names: Their Lore and Meaning".
9. Ridpath, Ian. "Star Tales - Leo".