Milky Way in Moonlight
23.04.2016

A waning crescent moon, early morning twilight, and Al Hamra's city lights on the horizon can't hide the central Milky Way in this skyscape from planet Earth. Captured in a single exposure...

Close Mars
31.08.2018

Still bright in evening skies, Mars was just past opposition and closest to Earth on July 31, a mere 57.6 million kilometers away. Captured only a week later, this remarkable image shows...

APOD: 2023 January 3 Б Kembles Cascade of Stars
3.01.2023

This line of stars is real. A little too faint to see with the unaided eye, KembleБs Cascade of stars inspires awe when seen with binoculars. Like the Big Dipper though, KembleБs Cascade is an asterism, not a constellation. The asterism is visible in the northern sky toward the long-necked constellation of the Giraffe (Camelopardalis).

Callisto Full Face
20.01.2002

Callisto's surface shows its age. While probably formed at the same time as Io, the difference between the surfaces of these two moons of Jupiter could hardly be greater. Io's surface is young, shows practically no impact craters, and is continually being repaved by the lava exploding from its many large volcanoes

Europa's Surface
13.08.1996

Voyager spacecraft images of Europa's surface, like the one above, are suggestive of sea ice on Earth. The criss-crossing dark streaks may indeed be cracks in its ice-covered surface caused by Jupiter's tidal stresses accompanied by the freezing and expansion of an underlying layer of water.

PanSTARRS from France
16.03.2013

Still looking for that comet? Comet PanSTARRS (C/2011 L4) naked-eye appearance in the northern hemisphere is described by successful comet spotters as a dim star with faint a tail. If you want to catch it the next few days could be your best bet.

Mysterious Changing feature on Titan
15.10.2014

What is that changing object in a cold hydrocarbon sea of Titan? Radar images from the robotic Cassini spacecraft orbiting Saturn have been recording the surface of the cloud-engulfed moon Titan for years. When...

Chamaeleon II Dark Cloud
2.08.2019

A small constellation hiding near the south celestial pole, The Chamaeleon boasts no bright stars. Stars are forming within its constellation boundaries though, in a complex of dark, dusty molecular clouds. Some 500 light-years...

Arecibo Telescope Collapse
9.12.2020

This was one great scientific instrument. Starting in 1963, the 305-meters across Arecibo Telescope in Puerto Rico USA reigned as the largest single-dish radio telescope in the world for over 50 years. Among numerous...

Contemplating the Sky
13.08.2002

Have you contemplated your sky recently? Last night was a good one for midnight meditators at many northerly locations as meteors from the Perseid meteor shower frequently streaked through. The Perseid meteor shower has slowly been building to a crescendo but should continue to be rewarding tonight and into the week.