Most of the city's population would have had less than half an hour to get under cover before radioactive dust fell.

So we know that dust falls from the atmosphere frequently.

The roar of voices made dust fall down from the ceiling.

Dust fell slowly down its sides and was scooped in once more.

The air was still and the dust fell like a little waterfall in the vacuum.

As dust and debris from the explosion fell around me, I jumped to my feet.

One piece hit so hard that dust and fine fragments fell from the inside of the crude roof.

New cracks appeared in the stone walls, and dust fell from the ceiling.

Dust fell from the grainy surface and floated to the ground.

"When enough dust and gas falls together, it can get hot enough to turn into a star, yes?"