dust

1 - Volcanoes are built by the accumulation of their own eruptive products, which are lava, ash flows, airborne ash and dust.

2 - Dust and a variety of gases from forest fires, volcanoes, and decaying material in rivers, oceans, and other bodies of water continually enter the atmosphere.

3 - The latest Japanese vacuum cleaners contain sensors that detect the amount of dust and type of floor.

4 - According to currently accepted theory, the Sun formed about 4.7 x 109 years ago from a cloud of gas and dust whose collapse was triggered by a supernova explosion.

5 - A meteor stream is composed of dust particles that have been ejected from a parent comet at a variety of velocities.