The impact flash may have been caused by the thermal emission from the impact itself or by the release of spacecraft volatiles, such as the small amount of hydrazine fuel remaining on board.

撞击的闪光可能来自撞击本身产生的热喷发，也可能是飞船上的挥发物，如剩余的少量肼燃料。

youdao

Static electricity could cause a small spark when a petrol pump nozzle is inserted which could in turn ignite fuel vapour in a flash fire.

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