1] Gemini Observatory, 670 North A'ohoku Place, Hilo, Hawaii 96720, USA [2].
1] Department of Terrestrial Magnetism, Carnegie Institution for Science, 5241 Broad Branch Road NW, Washington DC 20015, USA [2].
Nature. 2014 Mar 27;507(7493):471-4. doi: 10.1038/nature13156.
The observable Solar System can be divided into three distinct regions: the rocky terrestrial planets including the asteroids at 0.39 to 4.2 astronomical units (AU) from the Sun (where 1 AU is the mean distance between Earth and the Sun), the gas giant planets at 5 to 30 AU from the Sun, and the icy Kuiper belt objects at 30 to 50 AU from the Sun. The 1,000-kilometre-diameter dwarf planet Sedna was discovered ten years ago and was unique in that its closest approach to the Sun (perihelion) is 76 AU, far greater than that of any other Solar System body. Formation models indicate that Sedna could be a link between the Kuiper belt objects and the hypothesized outer Oort cloud at around 10,000 AU from the Sun. Here we report the presence of a second Sedna-like object, 2012 VP113, whose perihelion is 80 AU. The detection of 2012 VP113 confirms that Sedna is not an isolated object; instead, both bodies may be members of the inner Oort cloud, whose objects could outnumber all other dynamically stable populations in the Solar System.
岩石类地行星，包括距离太阳 0.39 到 4.2 天文单位（AU）范围内的小行星；距离太阳 5 到 30 AU 范围内的气态巨行星；以及距离太阳 30 到 50 AU 范围内的冰冷柯伊伯带天体。10 年前发现了直径 1000 公里的矮行星阋神星，它是独一无二的，因为它离太阳最近的点（近日点）是 76 AU，远远超过太阳系中任何其他天体。形成模型表明，阋神星可能是柯伊伯带天体和假设的在距离太阳 10000 AU 处的奥尔特云之间的一个连接。在这里，我们报告了第二个类似于阋神星的物体 2012 VP113 的存在，它的近日点是 80 AU。2012 VP113 的探测证实了阋神星不是一个孤立的物体；相反，这两个物体可能都是内奥尔特云的成员，其天体数量可能超过太阳系中所有其他动态稳定的天体群。
