Astronomy:Iota2 Librae
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Libra[1] |
| Right ascension | 15h 13m 19.1935s[2] |
| Declination | −19° 38′ 51.274″[2] |
| Apparent magnitude (V) | 6.066[3] |
| Characteristics | |
| Evolutionary stage | main sequence[2] |
| Spectral type | A2V[4] |
| Astrometry | |
| Radial velocity (Rv) | −7.61±0.56[2] km/s |
| Proper motion (μ) | RA: −50.808[2] mas/yr Dec.: −33.581[2] mas/yr |
| Parallax (π) | 11.2409 ± 0.2282[2] mas |
| Distance | 290 ± 6 ly (89 ± 2 pc) |
| Absolute magnitude (MV) | +1.86[1] |
| Details | |
| Mass | 1.84[5] M☉ |
| Radius | 2.314[6] R☉ |
| Luminosity | 20.33[6] L☉ |
| Surface gravity (log g) | 3.95[5] cgs |
| Temperature | 8,526±290[5] K |
| Age | 363[5] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
Iota2 Librae is a faint, sixth-magnitude star situated in the zodiacal constellation Libra. It has a stellar spectrum of A2V. This indicate that it is in the main sequence. Parallax measurements imply a distance of 89 parsecs (290 ly) from Earth. At this distance, interstellar extinction caused by interveining gas and dust makes Iota2 Librae 0.44 magnitudes fainter as seen from Earth. The star is currently drifting closer at 7.61 km/s.[2]
This A-type star has 84% more mass and 2.3 times the radius of the Sun. It is about 360 million years old, is 20 times more energetic and 48% hotter than the Sun, its surface has an effective temperature of 8,526 K.[6][5] It is also known by its Flamsteed designation 25 Librae, Iota2 Librae is the Bayer designation, with the corresponding Greek letter being shared with another star, Iota1 Librae. Other designations, like HD 134967 or HR 5656, are catalogue entries.
References
- ↑ 1.0 1.1 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode: 2012AstL...38..331A XHIP record for this object at VizieR.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940 Gaia DR3 record for this source at VizieR.
- ↑ Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P. et al. (2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics 355. Bibcode: 2000A&A...355L..27H.
- ↑ Houk, N.; Smith-Moore, M. (1988). "Michigan Catalogue of Two-dimensional Spectral Types for the HD Stars. Volume 4, Declinations -26°.0 to -12°.0.". Michigan Catalogue of Two-dimensional Spectral Types for the HD Stars. Volume 4 4. Bibcode: 1988mcts.book.....H.
- ↑ 5.0 5.1 5.2 5.3 5.4 David, Trevor J.; Hillenbrand, Lynne A. (2015-05-01). "The Ages of Early-type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets". The Astrophysical Journal 804 (2): 146. doi:10.1088/0004-637X/804/2/146. ISSN 0004-637X. Bibcode: 2015ApJ...804..146D. Iota2 Librae's database entry at VizieR.
- ↑ 6.0 6.1 6.2 McDonald, I.; Zijlstra, A. A.; Watson, R. A. (2017-10-01). "Fundamental parameters and infrared excesses of Tycho-Gaia stars". Monthly Notices of the Royal Astronomical Society 471: 770–791. doi:10.1093/mnras/stx1433. ISSN 0035-8711. Iota2 Librae's database entry at VizieR.
- ↑ "Iota2 Librae". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=Iota2+Librae.
Coordinates: 
15h 13m 19s, −19° 38′ 51″
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