标题： 柯伊伯带最大天体的卫星 显示英文标题

标题： Satellites of the largest Kuiper belt objects

摘要： 我们利用刚刚启用的凯克天文台激光导星自适应光学系统，对柯伊伯带的四个最亮天体进行了搜寻，以检查它们是否存在卫星。 在这四个天体中有三个发现了卫星：冥王星（其已知的卫星卡戎广为人知）、2003 EL61 和 2003 UB313。 亮度排名第四的柯伊伯带天体 2005 FY9（仅次于冥王星的最亮柯伊伯带天体）在其周围 0.4 弧秒范围内、且亮度超过主星 0.5% 的范围内没有发现卫星。 这四个最亮柯伊伯带天体中有三个存在卫星，这一结果与柯伊伯带整体卫星比例相比，在 99.1% 的置信水平上不一致，表明这些最大的柯伊伯带卫星可能具有不同的形成机制。 2003 EL61 和 2003 UB313 的卫星相对于它们的主星分别只有主星亮度的 5% 和 2%，明显比其他已知的柯伊伯带天体卫星暗得多，再次表明它们可能有不同的起源。 显示英文摘要

摘要： We have searched the four brightest objects in the Kuiper belt for the presence of satellites using the newly commissioned Keck Observatory Laser Guide Star Adaptive Optics system. Satellites are seen around three of the four objects: Pluto (whose satellite Charon is well-known), 2003 EL61, and 2003 UB313. The object 2005 FY9, the brightest Kuiper belt object after Pluto, does not have a satellite detectable within 0.4 arcseconds with a brightness of more than 0.5% of the primary. The presence of satellites to 3 of the 4 brightest Kuiper belt objects is inconsistent with the fraction of satellites in the Kuiper belt at large at the 99.1% confidence level, suggesting a different formation mechanism for these largest KBO satellites. The satellites of 2003 EL61 and 2003 UB313, with fractional brightnesses of 5% and 2% of their primaries, respectively, are significantly fainter relative to their primaries than other known Kuiper belt object satellites, again pointing to possible differences in their origin.