"在'行星9'存在的情况下，2017 OF201在几亿年内就会被抛出太阳系，如果'行星9'不存在，它就会留下 来。"Napier说，显然，这并不是支持"行星9"存在的证据。 2017 OF201目前距离地球约90.5个天文单位（AU），大约是太阳到地球距离的90倍。由于绕太阳运行 的平均轨道比海王星轨道大，因此2017 OF201被称为海王星外天体（TNO）。它会穿过柯伊伯带，后 者是海王星轨道外的一个由冰质天体构成的圆盘状区域。 研究人员回顾了加拿大-法国-夏威夷望远镜7年来的19次观测数据，确定2017 OF201的近日点为 44.5AU，与冥王星轨道相似；而它与太阳最远的距离为1600AU，远超出太阳系的范围。 研究人员表示，这个遥远轨道的形成可能是2017 OF201与一颗巨行星相遇的结果。这颗行星将候选矮 行星挤出了太阳系。 来源：中国科学报 美国密歇根大学的Kevin Napier说，这颗天体会飞到太阳系外很远的地方，可能与银河系中的其他恒星 发生强烈的相互作用，就像它与太阳系中的一些行星相互作用一样。 近日，一项公布于预印本平台arXiv的研究称，科学家在太阳系外围发现了一颗潜在矮行星——201 ...

Core Viewpoint - A new comet named SWAN is rapidly approaching the Sun, expected to reach its closest point to the Sun on May 1, with an estimated brightness of around magnitude 7 [1][3]. Group 1: Comet Characteristics - The SWAN comet was first observed by the SWAN camera on the European Space Agency's SOHO spacecraft in late March and was officially named "C/2025 F2 (SWAN)" by the International Astronomical Union on April 10 [1][2]. - The comet has a parabolic orbit with an eccentricity of 1.0000995, indicating it will not return after its close approach to the Sun [1][2]. - SWAN is characterized by its green appearance due to diatomic carbon in its coma, which reflects sunlight [2]. Group 2: Observational Details - The comet is currently moving from the northern hemisphere towards the southern hemisphere, with its closest approach to the Sun occurring at approximately 50 million kilometers, within the orbit of Mercury [2]. - It is expected to be observable from the northern hemisphere until around May 8, after which it will become increasingly difficult to see as it moves southward [2]. - There is uncertainty regarding the comet's stability as it approaches the Sun, with potential for disintegration due to solar heat, which has already been observed to some extent on April 20 [2]. Group 3: Public Observation - If the SWAN comet survives its close approach, it can be observed using binoculars or telephoto lenses in early May after sunset [3]. - The public is encouraged to check for the latest updates on the comet's status as it approaches the Sun [2].