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A comet trails a tail of light behind it as it moves.
Literal
Comet [topic-は] orbit-while behind [locative-に] light [possessive-の] tail [object-を] drags.
An astronomy description. 彗星 (すいせい) 'comet' — 彗 is an unusual kanji ('broom'), reflecting the Chinese name 'broom star' for the tail-sweeping appearance. 運行 ('movement, orbit, operation') is used for celestial bodies and also for train schedules. 尾を引く ('to drag a tail') — 引く here means 'to pull/drag' rather than its other meanings. ~ながら links the simultaneous actions.