WR 25HD 93162)是在船底座星云湍流恒星形成区的联星系统,距离地球大约6,800光年。它包含一颗沃夫–瑞叶星和一颗热且明亮伴星,并且是川普勒16星团的成员。

WR 25
Location of WR 25的位置(红圈)
Credit: ESO
观测资料
历元 J2000.0
星座 船底座
星官
赤经 10h 44m 10.337s[1]
赤纬 -59° 43′ 11.41″[1]
视星等(V) 8.80[2]
特性
演化阶段沃夫–瑞叶星
光谱分类O2.5If*/WN6 + OB[3]
天体测定
径向速度 (Rv)−34.6[4] km/s
自行 (μ) 赤经:−6.813±0.057[5] mas/yr
赤纬:2.721±0.055[5] mas/yr
视差 (π)0.4763 ± 0.0329[5] mas
距离6,800 ± 500 ly
(2,100 ± 100 pc)
绝对星等 (MV)-6.98[6]
轨道[4]
绕行周期 (P)207.85 days
半长轴 (a)156 R
偏心率 (e)0.50
半振幅 (K1)
(primary)
44 km/s
详细资料
WR
质量98[6] M
半径20.24[6] R
亮度 (bolometric)2,400,000[6] L
温度50,100[6] K
其他命名
HD 93162、2微米全天巡天 J10441038-5943111、WR 25、XMMU J104410.3-594311、CD−59°3282、PPM 339385、SAO 238408、川普勒16 177、GSC 08626-01989、UBV 9882、Hen 3-478
参考数据库
SIMBAD资料

光谱

WR 25因为它的亮度和光谱以宽发射线为主,在19世纪就被认定为沃夫–瑞叶星[7]。它的光谱包含氢线,介于经典的WN星和O型超巨星之间。这导致早期报告是联星,例如WN7星加上O7的恒星[8]。它也被描述为WN7 + abs[9]和WN6ha[10]。WR 25的光谱被归类为特定分类引进的热斜杠星,O2.5If*/WN6 。由许多微弱的发射谱线,认识到有氮的存在,还有一些氢和氦的吸收线。这个分类表示比WN6ha光谱类型更精细,有更弱的发射线和更强的吸收线[11]。但是无法清楚的检测到伴星的光谱,而对伴星的认识毫无贡献[4]

性质

 
WR 25是影像中最亮的恒星。在其左侧的橙色星只是前景星。

WR 25系统的主星大约比太阳亮240万倍,并照亮了川普勒16星团的远端。用于推导恒星参数的模型不适合在联星系统中使用,作者指出伴星占系统亮度的15%以上,因此亮度极不稳定。早先基于电离通量测量的估计所产生的值为太阳的150万倍,其它物理数据的估计值也相应降低[12]

伴星被认为是一颗年轻的炙热大质量恒星,类似于其它已知的WR + O 或WR + WR联星。据报导,它曾被视为O4超巨星,但后续的测量仍然不确定确实的光谱类型。两颗炙热恒星的恒星风碰撞,产生硬X射线[13],而早在检测到208天的轨道周期之前出,就怀疑是联星[4]

WR 25虽然非常明亮,但由于星云中大量灰尘的消光,以及大部分的辐射是在紫外线,所以无法以肉眼看见,而只能在X射线和红外线中观测[13][14]

WR 25位于川普勒16星团的西侧边界处,是银河系中最巨大的OB星协船底座OB1的一部分[15]。由于它极端的亮度,对恒星环境有极大的影响,从恒星移动离开的细长弧线和细丝中可以看到手指星云[16]

相关条目

参考资料

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