Denebola
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| Observation data Equinox J2000 |
|
|---|---|
| Constellation | Leo |
| Right ascension | 11h 49m 03.6s |
| Declination | +14° 34′ 19.0″ |
| Apparent magnitude (V) | 2.14 |
| Characteristics | |
| Spectral type | A3 V |
| U-B color index | +0.07 |
| B-V color index | +0.09 |
| Variable type | δ Scuti type |
| Astrometry | |
| Radial velocity (Rv) | -0.2 km/s |
| Proper motion (μ) | RA: -499.02 mas/yr Dec.: -113.78 mas/yr |
| Parallax (π) | 90.16 ± 0.89 mas |
| Distance | 36.2 ± 0.4 ly (11.1 ± 0.1 pc) |
| Absolute magnitude (MV) | 1.91 |
| Details | |
| Mass | 2.3 M☉ |
| Radius | 1.5 R☉ |
| Luminosity | 12 L☉ |
| Temperature | 8,500 K |
| Metallicity | ? |
| Rotation | ? |
| Age | ? years |
| Other designations | |
| Database references | |
| SIMBAD | data |
Denebola (β Leo / β Leonis / Beta Leonis) is the second brightest star in the constellation Leo. Its name is shortened from Deneb Alased, from the Arabic phrase ذنب الاسد ðanab al-asad "tail of the lion", as it represents the lion's tail. (Deneb in Cygnus has a similar name origin.)
Denebola is an A-type star, with a surface temperature of about 8500 K. It is about 36 light years distant from earth, and has a luminosity about twelve times that of the sun. Its apparent magnitude is 2.14. Denebola is a Delta Scuti type variable star, meaning its luminosity varies very slightly over a period of a few hours.
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[edit] Evidence for a dusty disk
Denebola shows a strong infrared excess, which means there must be a disk of cool dust in orbit around it. As our solar system is believed to have formed out of such a disk, Denebola and similar stars such as Vega and Beta Pictoris may be good candidate locations for extrasolar planets. The dust surrounding Denebola has a temperature of about 120 K. Unsuccessful attempts have been made to image the dust disk, implying that the disk is much smaller than that surrounding Beta Pictoris, which has been imaged frequently.
[edit] Supercluster membership
Kinematic studies have shown that Denebola is part of a stellar association dubbed the IC 2391 supercluster. All the stars of this group share a roughly common motion through space, although they are not gravitationally bound. This implies that they were born in the same location, and perhaps initially formed an open cluster. Other stars in this association include Alpha Pictoris, Beta Canis Minoris and the open cluster IC 2391. In total more than sixty probable members of the group have been identified.
[edit] References
- Cote J. (1987), B and A type stars with unexpectedly large colour excesses at IRAS wavelengths, Astronomy and Astrophysics (ISSN 0004-6361), v. 181, p. 77-84
- Eggen O.J. (1991), The IC 2391 supercluster, Astronomical Journal (ISSN 0004-6256), v. 102, p. 2028-2040
- Smith B.A., Fountain J.W., & Terrile R.J. (1992), An optical search for Beta Pictoris-like disks around nearby stars, Astronomy and Astrophysics (ISSN 0004-6361), v. 261, p. 499-502
