Eta Andromedae
Data pengamatan Epoch J2000.0 Equinox J2000.0 (ICRS) | ||
Rasi bintang | Andromeda | |
Asensio rekta | 00j 57m 12.4000d[1] | |
Deklinasi | +23° 25′ 03.533″[1] | |
Magnitudo semu (V) | 4.403[1] | |
Karakteristik | ||
Klasifikasi bintang | G8III-IV[2] | G8III-IV[2] |
U-B Indeks warna | +0.69[3] | |
B-V Indeks warna | +0.94[3] | |
R-I Indeks warna | +0.48[3] | |
Astrometri | ||
Kecepatan radial (Rv) | −10.3 ± 0.9[1] km/d | |
Gerak diri: | ||
RA (μα cos δ) | −43.72[1] m.b/thn | |
Dec. (μδ) | −46.06[1] m.b/thn | |
Paralaks (π) | 13.44 ± 0.75[1] m.b | |
Jarak | 240 ± 10 tc (74 ± 4 pc) | |
Magnitudo mutlak (MV) | 0.52 ± 0.06[2] | 1.07 ± 0.07[2] |
Details | ||
Massa | 2.6 ± 0.35[4] M☉ | 2.3 ± 0.31[4] M☉ |
Gravitasi permukaan (log g) | 2.8[2] | 3.0[2] |
Luminositas (bolometriks) | 65 ± 3[2] L☉ | 39 ± 3[2] L☉ |
Temperatur | 4900[2] K | 4900[2] K |
Umur | 8×108 [2] tahun | |
Orbit[5] | ||
Periode (P) | 115.72 ± 0.01 d | |
Sumbu semi-mayor (a) | 10.37 ± 0.03 mas | |
Eksentrisitas (e) | 0.006 ± 0.002 | |
Inklinasi (i) | 30.5 ± 0.4° | |
Bujur node menaik (Ω) | 69.4 ± 0.5° | |
Periastron epos (T) | 48013 ± 1 MJD | |
Argumen periastron (ω) (secondary) | 215 ± 4° | |
Referensi Database | ||
SIMBAD | data | |
Nama lain | ||
η And, Eta Andromedae, Eta And, 38 Andromedae, 38 And, MKT 2, FOX 116A, BD+22°153, CCDM J00572+2325A, FK5 2060, GC 1136, HD 5516, HIP 4463, HR 271, IDS 00519+2253 A, PPM 90327, SAO 74388, WDS 00572+2325A/Aa.[1] Entry 00572+2325, discoverer code MKT 2, components Aa,
The Washington Double Star Catalog, United States Naval Observatory. Accessed on line August 27, 2008.</ref> | ||
Eta Andromedae (Eta And / η Andromedae / η And) adalah bintang ganda yang berada di rasi Andromeda. Sistem bintang ini terdiri dari dua bintang sub raksasa tipe G (G-type subgiant)]] dengan periode orbit 115.7 hari dan magnitudo keseluruhan 4.40.[1][2]
Sejarah pengamatan
[sunting | sunting sumber]Eta Andromedae ditemukan dan diamati sebagai bintang ganda pada tahun 1899 dan 1900.[6] Its orbit was computed in 1946 from spectroscopic observations.[7] Pada pengamatan tahun 1990 sampai 1992, Eta Andromedae diamati melalui Mark III Stellar Interferometer di Mount Wilson Observatory, California, Amerika Serikat. Hasil pengamatini ini dilaporkan pada tahun 1993.[2]
Lokasi
[sunting | sunting sumber]Komponen visual
[sunting | sunting sumber]Data pengamatan Epos J2000.0 Ekuinoks J2000.0 (ICRS) | |
---|---|
Rasi bintang | Andromeda |
Asensio rekta | 00j 57m 04.9d[8] |
Deklinasi | +23° 23′ 43″[8] |
Magnitudo tampak (V) | 11.5[8] |
Posisi (relatif ke η And) | |
Epoch pengamatan | 1997 |
Jarak sudut | 129.2″ |
Sudut posisi | 232° Entry 00572+2325, discoverer code FOX 116, components AB,
The Washington Double Star Catalog, United States Naval Observatory. Accessed on line August 23, 2008.</ref> |
Referensi basis data | |
SIMBAD | data |
Penamaan lain | |
Bintang ini memiliki magnitudo 11.5, terpisah 129.2 arcsecond dari komponen utama.
Etimologi
[sunting | sunting sumber]Nama lain yang diberikan oleh para astronom untuk bintang ini adalah:
Nama lain | Asal bahasa | Arti |
---|---|---|
奎宿一 / Kuísuyī | China | bintang pertama pada rasi Kaki[9] |
奎宿西南小星 / Kuísuxīnánxiǎoxīng | China | bintang kecil di baratdaya rasi Kaki[1] |
Quae in cubito sinistro (Almagest) | Latin | yang berada di siku kiri (sang perawan yang dirantai) [10] |
Referensi
[sunting | sunting sumber]- ^ a b c d e f g h i j HD 5516 -- Spectroscopic binary, database entry, SIMBAD. Accessed on line August 23, 2008. Kesalahan pengutipan: Tanda
<ref>
tidak sah; nama "sb0" didefinisikan berulang dengan isi berbeda - ^ a b c d e f g h i j k l m The spectroscopic binary eta Andromedae: Determination of the orbit by optical interferometry, C. A. Hummel et al., Astronomical Journal 106, #6 (December 1993), pp. 2486–2492, Bibcode: 1993AJ....106.2486H, DOI:10.1086/116816.
- ^ a b c HR 271, 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 August 23, 2008.
- ^ a b Table 2, Resolved double-lined spectroscopic binaries: A neglected source of hypothesis-free parallaxes and stellar masses, D. Pourbaix, Astronomy and Astrophysics Supplement 145 (August 2000), pp. 215–222, Bibcode: 2000A&AS..145..215P.
- ^ Entry 00572+2325, Sixth Catalog of Orbits of Visual Binary Stars, United States Naval Observatory. Accessed on line August 27, 2008.
- ^ A list of nine stars whose velocities in the line of sight are variable, W. W. Campbell and W. H. Wright, Astrophysical Journal 12 (November 1900), pp. 254–257, Bibcode: 1900ApJ....12..254C, DOI:10.1086/140765.
- ^ The Spectroscopic Binary η Andromedae, Katherine C. Gordon, Astrophysical Journal 103 (January 1946), pp. 13–15, Bibcode: 1946ApJ...103...13G.
- ^ a b c d BD+22 153B -- Star in double system, database entry, SIMBAD. Accessed on line August 22, 2008.
- ^ salah satu rasi bintang menurut bangsa Cina
- ^ http://www.atlascoelestis.com/alsufi%2020.htm
Pranala luar
[sunting | sunting sumber]- η Andromedae Diarsipkan 2009-08-27 di Wayback Machine. at Alycone Software's Star Data Pages
- Image η Andromedae