Dust

Dust is fine particles of matter from various origins.

By April 2151, the only other inhabited planet besides Earth had visited, featured only dust-dwelling ticks. Later, Malcolm Reed claimed if he didn't realign the navigational deflector of space dust would damage the hull of Enterprise. 

The Andorian Tholos told T'Pol in June of 2151 that most Vulcans smell of dust but she was different. 

In 2266, Eve McHuron apologized for coughing, saying it must be the dust in the air that caused it. Ben Childress told her Rigel XII was always like that. 

In 2267, Montgomery Scott attributed the shorting of a circuit on the SS Botany Bay to dust. 

In 2268, Spock noted the presence of dust on various instruments in the Vians' laboratory, suggesting they had not been used for some time. 

The nebula encountered by USS Voyager in 2371 consisted of hydrogen, helium, hydroxyl radicals, and some local dust nodules. That was no problem for Voyager to navigate.