维基百科
天兔座AK
天兔座AK是南天星座天兔座中的一顆變星。它的視星等為6.141等[3]，因此，根據波特爾暗空分類法，在夜間它從鄉村天空中隱約可見。這顆恆星與廁三形成目視雙星：兩者的角距離為97"，使得即使在最佳條件下也很難用肉眼將它們分開[12]。廁三和天兔座AK都是大熊座移動星群的成員，它們在太空中有著相同的自行[6]。
| 觀測資料 曆元 J2000 | |
|---|---|
| 星座 | 天兔座 |
| 星官 | |
| 赤經 | 05h 44m 26.543s[2] |
| 赤緯 | −22° 25′ 18.77″[2] |
| 視星等（V） | 6.141[3] |
| 特性 | |
| 光谱分类 | K2V[4] |
| U−B 色指数 | +0.74[5] |
| B−V 色指数 | +0.96[5] |
| 变星类型 | BY Draconis[4] |
| 天体测定 | |
| 徑向速度 (Rv) | −9.57 ± 0.13[6] km/s |
| 自行 (μ) | 赤经：−304.4[7] mas/yr 赤纬：−352.2[7] mas/yr |
| 视差 (π) | 112.0[8] mas |
| 距离 | 28 ly (9.0[9] pc) |
| 绝对星等 (MV) | 6.31[3] |
| 詳細資料 | |
| 表面重力 (log g) | 4.66 ± 0.01[10] |
| 溫度 | 4,869 ± 61[10] K |
| 金属量 [Fe/H] | 0.01 ± 0.06[10] dex |
| 自轉速度 (v sin i) | 2.8 ± 1.8[6] km/s |
| 年齡 | 0.9[9] Gyr |
| 其他命名 | |
| 參考資料庫 | |
| SIMBAD | 资料 |
這是一顆天龍座BY型變星，由於恆星的活動而經歷亮度的變化。差異自轉導致變化週期取決於緯度活動的變化[4]。已經在天兔座AK檢測到X射線發射，它位於電波源或附近[8]。
對這顆變星的紅外線觀測顯示，在24μm的波長處有大量過量。這可能是由於廁三靠近視線，或者可能存在紅矮星伴星或塵埃盤。但在70μm處沒有觀察到過量[9]。
參考資料
- ^ 1.0 1.1 Nitschelm, C.; des Etangs, A. Lecavelier; Vidal-Madjar, A.; Ferlet, R.; Olsen, E. H.; Dennefeld, M. A three-year Strömgren photometric survey of suspected β Pictoris-like stars. Astronomy and Astrophysics Supplement Series. August 2000, 145: 275–281 [19 January 2022]. doi:10.1051/aas:2000243. （原始内容于2022-01-19）.
- ^ 2.0 2.1 Roeser, S.; Bastian, U., A new star catalogue of SAO type, Astronomy and Astrophysics Supplement Series, September 1988, 74 (3): 449–451, Bibcode:1988A&AS...74..449R.
- ^ 3.0 3.1 3.2 Nordström, Andersen; et al, The Geneva-Copenhagen survey of the Solar neighbourhood. Ages, metallicities, and kinematic properties of ~14000 F and G dwarfs, Publications of the Astronomical Society of Australia, 2004, 21 (2): 129–133, Bibcode:2004PASA...21..129N, doi:10.1071/AS04013 .
- ^ 4.0 4.1 4.2 Lecavelier Des Etangs, A.; et al, A photometric survey of stars with circumstellar material, Astronomy and Astrophysics, August 2005, 439 (2): 571–574, Bibcode:2005A&A...439..571L, doi:10.1051/0004-6361:20042401 .
- ^ 5.0 5.1 Mermilliod, J.-C., Compilation of Eggen's UBV data, transformed to UBV (unpublished), Catalogue of Eggen's UBV Data (SIMBAD), 1986, Bibcode:1986EgUBV........0M.
- ^ 6.0 6.1 6.2 Biazzo, K.; et al, Elemental abundances of low-mass stars in nearby young associations: AB Doradus, Carina Near and Ursa Major, Monthly Notices of the Royal Astronomical Society, December 2012, 427 (4): 2905–2916, Bibcode:2012MNRAS.427.2905B, S2CID 118617986, arXiv:1209.2591 , doi:10.1111/j.1365-2966.2012.22132.x.
- ^ 7.0 7.1 Høg, E.; et al, The Tycho-2 catalogue of the 2.5 million brightest stars, Astronomy and Astrophysics, March 2000, 355: L27–L30, Bibcode:2000A&A...355L..27H, doi:10.1888/0333750888/2862.
- ^ 8.0 8.1 Lazio, T. Joseph W.; et al, A Blind Search for Magnetospheric Emissions from Planetary Companions to Nearby Solar-Type Stars, The Astronomical Journal, January 2010, 139 (1): 96–101, Bibcode:2010AJ....139...96L, S2CID 118537554, arXiv:0910.3938 , doi:10.1088/0004-6256/139/1/96.
- ^ 9.0 9.1 9.2 Lawler, S. M.; et al, Explorations Beyond the Snow Line: Spitzer/IRS Spectra of Debris Disks Around Solar-type Stars, The Astrophysical Journal, November 2009, 705 (1): 89–111, Bibcode:2009ApJ...705...89L, S2CID 1272803, arXiv:0909.0058 , doi:10.1088/0004-637X/705/1/89.
- ^ 10.0 10.1 10.2 Prugniel, Ph.; et al, The atmospheric parameters and spectral interpolator for the MILES stars, Astronomy & Astrophysics, July 2011, 531: A165, Bibcode:2011A&A...531A.165P, S2CID 54940439, arXiv:1104.4952 , doi:10.1051/0004-6361/201116769.
- ^ V* AK Lep. SIMBAD. 斯特拉斯堡天文資料中心.
- ^ Kaler, James B., Gamma Leporis, Stars (University of Illinois), [2015-04-02], （原始内容于2022-12-05）.