Alpha Doradus
Alpha Doradus (Alpha Dor, α Doradus, α Dor) adalah bintang paling terang yang ad di rasi bintang Dorado. Dengan menggunakan sistem paralaks, jarak ke bintang ini dihitung sebesar 169 tahun cahaya (52 parsec).[6]
 Lokasi α Doradus (lingkaran) | ||
| Data pengamatan Epoch J2000.0 Equinox J2000.0 (ICRS) | ||
| Rasi bintang | Dorado | |
| Komponen | A | B |
| Asensio rekta | 04j 33m | 04j 33m |
| 59.778s | 59.782s | |
| Deklinasi | −55° 02′[1] | −55° 02′[2] |
| 41.91″ | 42.39″ | |
| Magnitudo semu (V) | 3.8[3] | 4.3[3] |
| Karakteristik | ||
| Klasifikasi bintang | A0IIIp[3] | B9IV[3] |
| U-B Indeks warna | −0.35[3] | |
| B-V Indeks warna | −0.10[3] | |
| R-I Indeks warna | −0.09[3] | |
| Variable type | ACV[4] | |
| Astrometri | ||
| Kecepatan radial (Rv) | 25.6 ± 0.9[5] km/s | |
| Gerak diri: | ||
| RA (μα cos δ) | 58.06[1] m.b/thn | 42.83[2] m.b/thn |
| Dec. (μδ) | 12.73[1] m.b/thn | 12.94[2] m.b/thn |
| Paralaks (π) | 19.34 ± 0.31[6] m.b | |
| Jarak | 169 ± 3 tc (51,7 ± 0,8 pc) | |
| Details | ||
| Massa | 3.33 ± 0.10[7] M☉ | 2.7[8] M☉ |
| Radius | 3.5 ± 0.3[7] R☉ | 1.9[8] R☉ |
| Gravitasi permukaan (log g) | 4.02 ± 0.07[7] | |
| Luminositas (bolometriks) | 195[7] L☉ | 70[8] L☉ |
| Temperatur | 11,588[7] K | 12,200[8] K |
| Rotasi | 2.94 days[7] | |
| Orbit[9] | ||
| Periode (P) | 12.1 y | |
| Sumbu semi-mayor (a) | 0.18″ | |
| Eksentrisitas (e) | 0.80 | |
| Inklinasi (i) | 31° | |
| Bujur node menaik (Ω) | 140° | |
| Periastron epos (T) | B1986 | |
| Argumen periastron (ω) (secondary) | 193° | |
| Referensi Database | ||
| SIMBAD | data | |
| Nama lain | ||
Bintang ini merupakan sistem bintang biner[8] dengan magnitudo semu bervariasi dari 3.26 - 3.30,[4] membuatnya menjadi bintang biner yang paling terang.[10]
Referensi
- HIP 21281, record for component 1, Hipparcos catalogue; CDS ID I/239.
- HIP 21281, record for component 2, Hipparcos catalogue; CDS ID I/239.
- HR 1465, database entry, The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version), D. Hoffleit and W. H. Warren, Jr., CDS ID V/50. Accessed on line September 3, 2008.
- alf Dor, database entry, The combined table of GCVS Vols I-III and NL 67-78 with improved coordinates, General Catalogue of Variable Stars, Sternberg Astronomical Institute, Moscow, Russia. Accessed on line September 3, 2008.
- V* alf Dor -- Variable Star, database entry, SIMBAD. Accessed on line September 3, 2008.
- van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752
. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. - North, P. (1998), "Do SI stars undergo any rotational braking?", Astronomy and Astrophysics, 334: 181–187, arXiv:astro-ph/9802286 , Bibcode:1998A&A...334..181N
- Kaler, James B., Stars, diakses tanggal 2012-03-04
- "Entry 04340-5503", Sixth Catalog of Orbits of Visual Binary Stars, United States Naval Observatory, diakses tanggal 2008-09-03
- Heintz, W. D. (1984), "Note on the orbit of alpha Doradus", The Observatory, 104: 88–89, Bibcode:1984Obs...104...88H
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