THE PECULIAR PHOTOMETRIC PROPERTIES OF 2010 WG9: A SLOWLY ROTATING TRANS-NEPTUNIAN OBJECT FROM THE OORT CLOUD
THE PECULIAR PHOTOMETRIC PROPERTIES OF 2010 WG9: A SLOWLY ROTATING TRANS-NEPTUNIAN OBJECT FROM THE OORT CLOUD
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DOI：
10.1088/0004-6256/146/1/17
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发表时间：
2013-05
期刊：
影响因子：
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通讯作者：
D. Rabinowitz;M. Schwamb;E. Hadjiyska;S. Tourtellotte;P. Rojo
中科院分区：
文献类型：
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作者：
D. Rabinowitz;M. Schwamb;E. Hadjiyska;S. Tourtellotte;P. Rojo
我们展示了 2010 WG9 的长期 BVRI 观测结果，这是由 La Silla-QUEST 南部天空巡天发现的直径约 100 公里的跨海王星天体 (TNO)，倾角极高，达到 70°。大部分观测数据是 2010 年 12 月至 2012 年 11 月期间在智利 Cerro Tololo 的 SMARTS 1.3 m 上使用 ANDICAM 获得的。 2011 年 2 月，欧洲南方天文台位于智利拉西拉的 3.5 m NTT 望远镜使用 EFOSC2 进行了额外观测。观测结果显示，正弦光曲线的振幅为 0.14 星等，周期为 5.4955 ± 0.0025 天，这可能是真实自转周期的一半。如此长的自转周期以前仅在潮汐演化的双星海天组织中观察到，这表明2010 WG9可能就是这样一个系统。我们预测标称间隔至少为 790 公里，可以通过哈勃太空望远镜和地面系统解析。我们测得 B − R = 1.318 ± 0.029 和 V − R = 0.520 ± 0.018，与适度红色的半人马座和达摩克洛伊星的颜色一致。在 I 波段波长，我们观察到颜色随旋转相位的变化异常大，R − I 范围从 0.394 ± 0.025 到 0.571 ± 0.044。我们还测量到 R 波段的绝对星等为 7.93 ± 0.05，太阳相位系数为 0.049 ± 0.019 mag deg−1。
We present long-term BVRI observations of 2010 WG9, an ∼100 km diameter trans-Neptunian object (TNO) with an extremely high inclination of 70° discovered by the La Silla–QUEST southern sky survey. Most of the observations were obtained with ANDICAM on the SMARTS 1.3 m at Cerro Tololo, Chile from 2010 December to 2012 November. Additional observations were made with EFOSC2 on the 3.5 m NTT telescope of the European Southern Observatory at La Silla, Chile in 2011 February. The observations reveal a sinusoidal light curve with amplitude 0.14 mag and period 5.4955 ± 0.0025 days, which is likely half the true rotation period. Such long rotation periods have previously been observed only for tidally evolved binary TNOs, suggesting that 2010 WG9 may be such a system. We predict a nominal separation of at least 790 km, resolvable with the Hubble Space Telescope and ground-based systems. We measure B − R = 1.318 ± 0.029 and V − R = 0.520 ± 0.018, consistent with the colors of modestly red Centaurs and Damocloids. At I-band wavelengths, we observe an unusually large variation of color with rotational phase, with R − I ranging from 0.394 ± 0.025 to 0.571 ± 0.044. We also measure an absolute R-band absolute magnitude of 7.93 ± 0.05 and solar phase coefficient of 0.049 ± 0.019 mag deg−1.