Free Republic

Explanation: What glows there? The answer depends: sea or sky? In the sea, the unusual blue glow is bioluminescence. Specifically, the glimmer arises from Noctiluca scintillans, single-celled plankton stimulated by the lapping waves. The plankton use their glow to startle and illuminate predators. This mid-February display on an island in the Maldives was so intense that the astrophotographer described it as a turquoise wonderland. In the sky, by contrast, are the more familiar glows of stars and nebulas. The white band rising from the artificially-illuminated green plants is created by billions of stars in the central disk of our Milky...

Explanation: Celestial sights of the southern sky shine above a cloudy planet Earth in this gorgeous night sky view. The scene was captured from an airliner's flight deck at 38,000 feet on a steady westbound ride to Lima, Peru. To produce the sharp airborne astrophotograph, the best of a series of short exposures were selected and digitally stacked. The broad band of the southern Milky Way begins at top left with the dark Coalsack Nebula and Southern Cross. Its expanse of diffuse starlight encompasses the the Carina Nebula and large Gum Nebula toward the right. Canopus, alpha star of Carina...