Sky obscured by clouds overhead.

Atmospheric phenomenon tinted by sunset.

Dense, opaque interstellar dust accumulation.

Visible mass of condensed water.

Sky becomes covered with clouds.

Device visualizing particle paths via condensation.

Collection of particles suspended airborne.

Area where electrons are likely found.

High-altitude forest, dense, moist fog.

Explosive nuclear reaction atmospheric formation.

Galaxies near Milky Way, irregular.

Atmospheric stratum containing condensed vapor.

Condensation of water vapor aloft.

Starting height of cloud formation.

(astronomy) A large and relatively dense cloud of cold gas and dust in interstellar space from which new stars are formed