2025年7月7日
Interstellar Comet 3I/ATLAS
Image Credit: NASA, JPL-Caltech
Explanation: It came from outer space. An object from outside our Solar System is now passing through at high speed. Classified as a comet because of its gaseous coma, 3I/ATLAS is only the third identified macroscopic object as being so alien. The comet’s trajectory is shown in white on the featured map, where the orbits of Jupiter, Mars, and Earth are shown in gold, red, and blue. Currently Comet 3I/ATLAS is about the distance of Jupiter from the Sun — but closing, with its closest approach to our Sun expected to be within the orbit of Mars in late October. Expected to pass near both Mars and Jupiter, 3I/ATLAS is not expected to pass close to the Earth. The origin of Comet 3I/ATLAS remains unknown. Although initial activity indicates a relatively normal comet, future observations about 3I/ATLAS‘ composition and nature will surely continue.
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星际彗星3I/ATLAS
影像提供: NASA, JPL-Caltech
说明: 这颗彗星来自外太空。目前有来自太阳系外的天体，正高速穿过我们的太阳系。由于拥有气态的彗发，故归类为彗星的3I/ATLAS，是第三颗确认来自太阳系外的天体。在上面这幅呈现太阳系内围的空间图示里，白色线为这颗彗星的轨迹，而木星、火星、及地球的轨道，则分别以金、红、与蓝色来标示。逐渐接近太阳的彗星3I/ATLAS，目前与太阳的间距和木星相当，而在今年的10月底最接近太阳时，预计会来到火星的轨道之内。此外，会掠过火星与木星附近、来处目前仍不明的彗星3I/ATLAS，预期并不会太靠近地球。虽然它初期的活动很像常见的彗星，但探索3I/ATLAS的组成及本质之观测，必然会持续下去。
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