Back الطرف (نجم) Arabic Alterf AST Alterf Catalan Alterf German Alterf Spanish Lambda Leonis French Lambda Leonis ID しし座ラムダ星 Japanese Alterf (Stär) LB Alterf Dutch
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Leo |
| Right ascension | 09h 31m 43.22754s[1] |
| Declination | +22° 58′ 04.6904″[1] |
| Apparent magnitude (V) | 4.32[2] |
| Characteristics | |
| Spectral type | K4.5 III[3] |
| U−B color index | +1.82[2] |
| B−V color index | +1.54[2] |
| Astrometry | |
| Radial velocity (Rv) | 24.27±0.19[4] km/s |
| Proper motion (μ) | RA: −20.17[1] mas/yr Dec.: −39.47[1] mas/yr |
| Parallax (π) | 9.91 ± 0.18 mas[1] |
| Distance | 329 ± 6 ly (101 ± 2 pc) |
| Absolute magnitude (MV) | −0.70[5] |
| Details[6] | |
| Mass | 1.29±0.18 M☉ |
| Radius | 44.93+0.85 −0.87 R☉ |
| Luminosity | 541.4±33.5 L☉ |
| Surface gravity (log g) | 1.70 cgs |
| Temperature | 4,152±53 K |
| Metallicity [Fe/H] | −0.21 dex |
| Rotational velocity (v sin i) | 8[7] km/s |
| Age | 3.62±1.37 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
Lambda Leonis (λ Leonis, abbreviated Lam Leo, λ Leo), formally named Alterf /ælˈtərf/,[9][10] is a star in the constellation of Leo. The star is bright enough to be seen with the naked eye, having an apparent visual magnitude of 4.32[2] Based upon an annual parallax shift of 0.00991 arcseconds, it is located about 329 light-years from the Sun. At that distance, the visual magnitude of the star is reduced by an interstellar absorption factor of 0.06 because of extinction.[4]
- ^ a b c d e Cite error: The named reference
vanLeeuwen2007was invoked but never defined (see the help page). - ^ a b c d Cite error: The named reference
Mermilliod1986was invoked but never defined (see the help page). - ^ Cite error: The named reference
Keenan1989was invoked but never defined (see the help page). - ^ a b Cite error: The named reference
Famaey2005was invoked but never defined (see the help page). - ^ Cite error: The named reference
Anderson2012was invoked but never defined (see the help page). - ^ Cite error: The named reference
Baines2018was invoked but never defined (see the help page). - ^ Cite error: The named reference
Bernacca1970was invoked but never defined (see the help page). - ^ Cite error: The named reference
SIMBADwas invoked but never defined (see the help page). - ^ Kunitzsch, Paul; Smart, Tim (2006). A Dictionary of Modern star Names: A Short Guide to 254 Star Names and Their Derivations (2nd rev. ed.). Cambridge, Massachusetts: Sky Pub. ISBN 978-1-931559-44-7.
- ^ "Naming Stars". IAU.org. Retrieved 16 December 2017.