Comet Churyumov Gerasimenko in Crescent
29.04.2015

What's happening to Comet 67P/ChuryumovGerasimenko? As the 3-km wide comet moves closer to the Sun, heat causes the nucleus to expel gas and dust. The Rosetta spacecraft arrived at the comet's craggily double nucleus last July and now is co-orbiting the Sun with the giant dark iceberg.

Phases of Venus
21.05.2020

Just as the Moon goes through phases, Venus' visible sunlit hemisphere waxes and wanes. This composite of backyard telescopic images illustrates the steady changes for Venus during its current stint as our evening star, as the inner planet grows larger but narrows to a thin crescent.

Neptune in Infrared
25.10.1999

Neptune has never looked so clear in infrared light. Neptune is the eighth most distant planet from the Sun, thirty times the Earth-Sun distance. Neptune is the fourth largest planet, almost four times Earth's diameter. Surprisingly, Neptune radiates about twice as much energy as it receives from the Sun.

Suspension Bridge Solargraph
15.01.2009

If every picture tells a story, this one might make a novel. The six month long exposure compresses the time from December 17, 2007 to June 21, 2008 into a single point of view.

APOD: 2024 December 4 Б Driveway Analemma
4.12.2024

Does the Sun return to the same spot on the sky every day?б No.б A more visual answer is an analemma, a composite of sky images taken at the same time and from the same place over a year.

Sunspot Metamorphosis: From Bottom to Top
16.02.2005

Sunspots -- magnets the size of the Earth -- are normally seen flat on the Sun. The above digital metamorphosis, however, shows a sunspot as it appears at increasing heights, effectively in three dimensions. The above...

APOD: 2024 May 26 Б A Solar Filament Erupts
26.05.2024

What's happened to our Sun? Nothing very unusual -- it just threw a filament. Toward the middle of 2012, a long standing solar filament suddenly erupted into space, producing an energetic coronal mass ejection (CME).

APOD: 2025 October 19 Б Comet Churyumov Gerasimenko Creates Its Tails
19.10.2025

Where do comet tails come from? There are usually no obvious places on the nuclei of comets from which the jets that create comet tails emanate. One of the best images of emerging jets...

A Prominent Solar Prominence
27.01.1997

One of the most spectacular solar sights is a prominence. A solar prominence is a cloud of solar gas held above the Sun's surface by the Sun's magnetic field. The Earth would easily fit under one of the loops of the prominence shown in the above picture.

Nacreous Clouds over Sweden
1.02.2025

Vivid and lustrous, wafting iridescent waves of color wash across this skyscape from northern Sweden. Known as nacreous clouds or mother-of-pearl clouds, they are rare. But their unforgettable appearance was captured in this snapshot on January 12 with the Sun just below the local horizon.