61 Cygni
Dari Wikipedia bahasa Indonesia, ensiklopedia bebas
 Expanded view of the star field around 61 Cygni. This system is located at the end of the arrow above. |
|
| Ciri-ciri | |
|---|---|
| Kelas spektrum | K5V / K7V |
| Indeks warna U-B | +1.155 / +1.242[1] |
| Indeks warna B-V | +1.139 / +1.320[1] |
| Jenis variabel | A: BY Draconis B: Flare star |
| Astrometri | |
| Kecepatan radial (Rv) | -64.3/-63.5 km/s |
| Gerak diri (μ) | RA: 4156.93/ 4109.17 mas/thn Dek.: 3259.39/ 3144.17 mas/thn |
| Paralaks (π) | 287.18 ± 1.51 mas |
| Jarak | 11,36 ± 0,06 tc (3,48 ± 0,02 pc) |
| Magnitudo mutlak (MV) | 7.48/8.33 |
| Detail | |
| 61 Cygni A | |
| Massa | 0.70[2] M☉ |
| Radius | 0.665 ± 0.005[3] R☉ |
| Gravitasi permukaan (log g) | 4.40[4] |
| Luminositas | 0.215 L☉ |
| Suhu | 4,526 ± 66[5] K |
| Metalisitas | [Fe/H] = -0.20[4] |
| Rotasi | 35.37 d[6] |
| 61 Cygni B | |
| Massa | 0.63[2] M☉ |
| Radius | 0.595 ± 0.008[3] R☉ |
| Gravitasi permukaan (log g) | 4.20[4] |
| Luminositas | 0.15 L☉ |
| Suhu | 4,077 ± 59[5] K |
| Metalisitas | [Fe/H] = -0.27[4] |
| Rotasi | 37.84 d[6] |
| Orbit bintang ganda visual | |
| Bintang sekunder | 61 Cygni B |
| Periode (P) | 678 ± 34 tahun |
| Sumbu semi-mayor (a) | 24.272 ± 0.592" |
| Eksentrisitas (e) | 0.49 ± 0.03 |
| Inklinasi (i) | 51 ± 2° |
| Bujur node (Ω) | 178 ± 2° |
| Epoch periastron (T) | 1709 ± 16 |
| Penamaan lain | |
GJ 820 A/B, Struve 2758 A/B, ADS 14636 A/B, GCTP 5077.00 A/B [7]
V1803 Cyg, HD 201091, HIP 104214, HR 8085, BD+38°4343, LHS 62
HD 201092, HIP 104217, HR 8086, BD+38°4344, LHS 63 |
|
61 Cygni merupakan bintang ganda di rasi Cygnus. Bintang ini terdiri dari dua bintang katai tipe K (K-type dwarf) yang saling mengorbit. 61 Cygni adalah salah satu bintang yang menarik untuk diteliti oleh para astronom. Pada tahun 1838, Friedrich Wilhelm Bessel mengukur jarak antara keberadaanya dengan Bumi, dan menghasil angka sekitar 10.4 tahun cahaya, lebih dekat daripada hasil yang diperoleh pada pengujian terakhir (11.4 tahun cahaya)[8]. Setelah berbagai pengujian pada abad keduabelas, beberapa pelanet dilaporkan mengelilingi bintang ini, namun sejauh ini pernyataan tersebut belum teruji[9][10][11] To date, no planets have been confirmed in this system and all of the past claims are now considered spurious.
Etimologi [sunting]
Bintang ini disebut juga Bintang Bessel (Bessel's Star)[12] atau Piazzi's Flying Star,[13]
Selain rasi Cygnus, bintang ini juga merupakan anggota dari kelompok berikut :
| nama rasi / asterisma / kelompok | asal | arti | anggota lainnya |
|---|---|---|---|
| 61 Cygni Group[14] | (antara lain) : 31 Aql, HD 131111, HD 3443, β Col, π Men, HD 142, HD 55526, 14 Tau, HD 150275, 68 Vir, HD 53501 |
Referensi [sunting]
- ^ a b Blanco, C.; Marilli, E.; Catalano, S. (1979). "Photoelectric observations of stars with variable H and K emission components. III". Astronomy and Astrophysics Supplement Series 36: 297–306. Diakses 2007-02-04.
- ^ a b Staff (June 8, 2007). "List of the Nearest 100 Stellar Systems". Research Consortium on Nearby Stars, Georgia State University. Diakses 2007-07-15.
- ^ a b Kervella, P.; Mérand, A.; Pichon, B.; Thévenin, F.; Heiter, U.; Bigot, L.; Ten Brummelaar, T. A.; McAlister, H. A.; Ridgway, S. T.; Turner, N.; Sturmann, J.; Sturmann, L.; Goldfinger, P. J.; Farrington, C. (September 2008). "The radii of the nearby K5V and K7V stars 61 Cygni A & B. CHARA/FLUOR interferometry and CESAM2k modeling". Astronomy and Astrophysics 488 (2): 667–674. doi:10.1051/0004-6361:200810080.
- ^ a b c d Luck, R. Earle; Heiter, Ulrike (2005). "Stars within 15 Parsecs: Abundances for a Northern Sample". The Astronomical Journal 129 (2): 1063–1083. doi:10.1086/427250. Diakses 2007-07-17.
- ^ a b van Belle, Gerard T.; von Braun, Kaspar (2009). "Directly Determined Linear Radii and Effective Temperatures of Exoplanet Host Stars". The Astrophysical Journal 694 (2): 1085–1098. doi:10.1088/0004-637X/694/2/1085.
- ^ a b Böhm-Vitense, Erika (March 2007). "Chromospheric Activity in G and K Main-Sequence Stars, and What It Tells Us about Stellar Dynamos". The Astrophysical Journal 657 (1): 486–493. doi:10.1086/510482.
- ^ "SIMBAD Query Result: ADS 14636 AB -- Double or multiple star". SIMBAD. Centre de Données astronomiques de Strasbourg. Diakses 2009-04-01. (61 Cygni)
- ^ Frommert, Hartmut; Kronberg, Christine. "Friedrich Wilhelm Bessel". Students for the Exploration and Development of Space. Diakses 2009-04-03.
- ^ Walker, G. A. H.; Walker, A. R.; Irwin, A. W.; Larson, A. M.; Yang, S. L. S.; Richardson, D. C (1995). "A search for Jupiter-mass companions to nearby stars". Icarus 116 (2): 359–375. doi:10.1006/icar.1995.1130.
- ^ Cumming, A.; Marcy, G. W.; Butler, R. P. (1999). "The Lick planet search: detectability and mass thresholds". Astrophysical Journal 526: 890–915. doi:10.1086/308020.
- ^ Wittenmyer, R. A.; Endl, M.; Cochran, W.D.; Hatzes , A.; Walker, G. A. H.; Yang, S. L. S.; Paulson, D. B. (2006). "Detection limits from the McDonald Observatory planet search program". Astronomical Journal 132: 177–188. doi:10.1086/504942.
- ^ Pannekoek, Anton (1989). A History of Astronomy. Courier Dover Publications. p. 343. ISBN 0486659941.
- ^ Hirshfeld, Alan (2001). Parallax: The Race to Measure the Cosmos. Macmillan. ISBN 0716737116.
- ^ Eggen, O. J. (1959). "White dwarf members of the 61 Cygni group". The Observatory 79: 135–39. Diakses 2007-07-17. – Gives space velocity components of U=+94, V=-53 and W=-7 for HD 201091/2.
Pranala luar [sunting]
- "61 Cygni 2". SolStation. Diakses 2007-07-16.
- Kaler, James B. "61 Cygni". University of Illinois at Urbana-Champaign. Diakses 2007-07-16.
