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来自澳大利亚的伦纳德彗星特写

(原标题: Comet Leonard Closeup from Australia)

2022-01-12

浏览次数: 15

莱纳德彗星近距离看是什么样子?虽然我们无法到达那里,但通过小型望远镜对彗星的彗发和内部彗尾进行成像给了我们一个很好的想法。顾名思义,离子尾巴是由电离气体组成的,这种气体受到来自太阳的紫外线的激发,并被太阳风向外推。太阳风是由太阳复杂且不断变化的磁场构造而成的。多变的太阳风加上从彗核喷出的不同气体射流的影响,解释了彗尾复杂的结构。随着风的移动,伦纳德彗星尾巴的结构可以从太阳向外移动,甚至随着时间的推移改变了它的波浪状外观。离子尾部的蓝色主要是一氧化碳分子的重组,而彗星头部周围的昏迷的绿色主要是由少量的双原子碳分子的重组产生的。双原子碳在大约50小时内被阳光破坏,这就是为什么它的绿光不能进入离子尾的原因。这张特色图片是1月2日在澳大利亚赛丁泉天文台拍摄的。伦纳德彗星目前在地球的南半球观测效果最好,它已经绕着太阳转了一圈,现在正在离开太阳系。

查看原文解释

What does Comet Leonard look like up close? Although we can't go there, imaging the comet's coma and inner tails through a small telescope gives us a good idea. As the name implies, the ion tail is made of ionized gas -- gas energized by ultraviolet light from the Sun and pushed outward by the solar wind. The solar wind is quite structured and sculpted by the Sun's complex and ever changing magnetic field. The effect of the variable solar wind combined with different gas jets venting from the comet's nucleus accounts for the tail's complex structure. Following the wind, structure in Comet Leonard's tail can be seen to move outward from the Sun even alter its wavy appearance over time. The blue color of the ion tail is dominated by recombining carbon monoxide molecules, while the green color of the coma surrounding the head of the comet is created mostly by a slight amount of recombining diatomic carbon molecules. Diatomic carbon is destroyed by sunlight in about 50 hours -- which is why its green glow does not make it far into the ion tail. The featured image was taken on January 2 from Siding Spring Observatory in Australia. Comet Leonard, presently best viewed from Earth's Southern Hemisphere, has rounded the Sun and is now headed out of the Solar System.

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