Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2023 May 29
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 Way Galaxy. Also visible in the sky is the star cluster Omega Centauri, toward the left, and the famous Southern Cross asterism in the center. Red-glowing nebulas include the bright Carina Nebula, just right of center, and the expansive Gum Nebula on the upper right.
Authors & editors:
Jerry Bonnell (UMCP)
NASA Official: Phillip Newman Specific rights apply.
A service of: ASD at NASA / GSFC,
NASA Science Activation
& Michigan Tech. U.