APOD: 2023 May 29 Б Milky Way over a Turquoise Wonderland
29.05.2023

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.

The 37 Cluster
14.05.2024

For the mostly harmless denizens of planet Earth, the brighter stars of open cluster NGC 2169 seem to form a cosmic 37. Did you expect 42? From our perspective, the improbable numerical asterism appears solely by chance. It lies at an estimated distance of 3,300 light-years toward the constellation Orion.

The Gamma Ray Sky
22.02.1997

What if you could "see" gamma rays? If you could, the sky would seem to be filled with a shimmering high-energy glow from the most exotic and mysterious objects in the Universe.

A True Image from False Kiva
29.09.2008

Is there any place in the world you could see a real sight like this? Yes. Pictured above is single exposure image spectacular near, far, and in between. Diving into the Earth far in the distance is part of the central band of our Milky Way Galaxy, taken with a long duration exposure.

Perseid Storm
21.08.2010

Storms on the distant horizon and comet dust raining through the heavens above are combined in this alluring nightscape. The scene was recorded in the early hours of August 13 from the Keota Star Party site on the Pawnee National Grasslands of northeastern Colorado, USA.

Winter Hexagon Over Stagecoach Colorado
3.01.2011

If you can find Orion, you might be able to find the Winter Hexagon. The Winter Hexagon involves some of the brightest stars visible, together forming a large and easily found pattern in the winter sky of Earth's northern hemisphere.

3 ATs
21.04.2012

Despite their resemblance to R2D2, these three are not the droids you're looking for. Instead, the enclosures house 1.8 meter Auxiliary Telescopes (ATs) at Paranal Observatory in the Atacama Desert region of Chile.

Tombaugh 4
21.10.2006

Clyde Tombaugh discovered planet Pluto in 1930 while surveying the skies with the 13-inch Lawrence Lowell Telescope. But the skilled and careful astronomer also went on to discover star clusters, comets, asteroids, and clusters of galaxies. For example, pictured is galactic or open star cluster Tombaugh 4 in the northern constellation Cassiopeia.

NGC 7789: Galactic Star Cluster
9.07.1999

At 1.6 billion years old, this cluster of stars is beginning to show its age. NGC 7789 is an open or galactic star cluster about 8,000 light-years distant toward the constellation Cassiopeia and lies near the plane of our Milky Way galaxy.

The Great Carina Nebula
27.10.2007

A jewel of the southern sky, the Great Carina Nebula, aka NGC 3372, spans over 300 light-years, one of our galaxy's largest star forming regions. Like the smaller, more northerly Orion Nebula...