Radiation from the sun pushes dust particles away from the coma, forming a dust tail, while charged particles from the sun convert some of the comet's gases into ions, forming an ion tail.

从太阳而来的辐射，将尘埃粒子吹离彗发，形成尘埃彗尾；同时，来自太阳的带电粒子将一些彗星气体电离成离子，形成离子彗尾。

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The fan-shaped region that stretches upward from Johnson's nucleus (yellow ball in the middle) represents the dust "tail" of the comet.

从Johnson彗星的彗核（照片中部的黄色球体）向上延展的扇状区域描绘出了这颗彗星的尘埃“尾”。

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It already has a 64, 000km-long tail of dust and gas that will become visible to the naked eye later in the year - a trail scientists will study closely.

BBC: Comet Ison caught on film by Deep Impact craft

As a comet gets closer to the sun, the sun's heat causes these elements to melt, spewing out dust and gas in a brilliant tail.

CNN: Welcome to the year of the comet (we hope)