APOD: 2023 December 20 Б Ice Halos over Bavaria
20.12.2023

What's causing those unusual sky arcs? Ice crystals. While crossing a field of fresh snow near Fцssen, Bavaria, Germany, earlier this month, the photographer noticed that he had entered an ice fog.

A View Toward M106
22.02.2024

Big, bright, beautiful spiral, Messier 106 dominates this cosmic vista. The nearly two degree wide telescopic field of view looks toward the well-trained constellation Canes Venatici, near the handle of the Big Dipper. Also...

Voyager at 90 AU
20.11.2003

Launched in 1977, Voyager 1 is now about 12 light-hours or 90 astronomical units (AU) from the Sun, making this spacecraft humanity's most distant ambassador to the cosmos. Well beyond the orbits...

APOD: 2024 September 9 Б Mars: Moon, Craters, and Volcanos
9.09.2024

If you could fly over Mars, what might you see? The featured image shows exactly this in the form of a Mars Express vista captured over a particularly interesting region on Mars in July. The picture's most famous feature is Olympus Mons, the largest volcano in the Solar System, visible on the upper right.

Storm Alley on Saturn
2.11.2004

What causes storms on Saturn? To help find out, scientists commanded the robot Cassini spacecraft now orbiting Saturn to inspect a circulating band of clouds nicknamed "Storm Alley." This westwardly moving cloud ring...

The Nucleus of Comet Tempel 1
15.09.2005

Approaching the nucleus of comet Tempel 1 at ten kilometers per second, the Deep Impact probe's targeting camera recorded a truly dramatic series of images. Successive pictures improve in resolution and have been...

Coronal Rain on the Sun
27.05.2018

Does it rain on the Sun? Yes, although what falls is not water but extremely hot plasma. An example occurred in mid-July 2012 after an eruption on the Sun that produced both a Coronal Mass Ejection and a moderate solar flare. What was more unusual, however, was what happened next.

Shackleton from ShadowCam
5.05.2023

Shackleton crater lies at the lunar south pole. Peaks along the 21 kilometer diameter are in sunlight, but Shackleton's floor is in dark permanent shadow. Still, this image of the shadowed rim wall...

Churning Clouds on Jupiter
11.08.2020

Where is Jupiter's ammonia? Gaseous ammonia was expected to be seen in Jupiter's upper atmosphere by the orbiting Juno spacecraft -- but in many clouds is almost absent. Recent Juno data, however, gives some clues: some high-level clouds appear to be home to an unexpected type of electrical discharge dubbed shallow lightning.

An Extreme UltraViolet View of the Comet
30.03.1996

As the Sun floods Comet Hyakutake with ultraviolet light gases in the coma scatter the radiation and fluoresce making the comet a bright source in the ultraviolet sky. The above image made using data...