Jyvцskylц in the Sky
25.01.2024

You might not immediately recognize this street map of a neighborhood in Jyvцskylц, Finland, planet Earth. But that's probably because the map was projected into the night sky and captured with an allsky camera on January 16. The temperature recorded on that northern winter night was around minus 20 degrees Celsius.

Shadow at the Lunar South Pole
28.11.1995

In 1994, the space probe Clementine spent 70 days in lunar orbit mapping the Moon's surface. Shown above is a dramatically detailed composite view centered on the Moon's South Pole constructed from 1500 Clementine images.

Mammatus Clouds Over Mexico
30.12.2007

Normal cloud bottoms are flat because moist warm air that rises and cools will condense into water droplets at a very specific temperature, which usually corresponds to a very specific height. After water droplets form that air becomes an opaque cloud.

Uranus's Moon Umbriel: A Mysterious Dark World
7.04.1996

Why is Umbriel so dark? This dark moon reflects only half the light of other Uranus' moons such as Ariel. And what is that bright ring at the top? Unfortunately, nobody yet knows. These questions presented themselves when Voyager 2 passed this satellite of Uranus in January 1986.

Leonids 1998: A Safe Meteor Storm
16.11.1998

You're in no danger. During the meteor storm occurring tonight and tomorrow, thousands of bits of ice and rock will likely rain onto the Earth. Few, if any, will hit the ground. Touted as potentially the most active meteor shower since 1966, the Leonids of 1998 will be tracked by observers the world over.

Huygens Images Titan s Surface
15.01.2005

After a seven year interplanetary voyage on board the the Cassini spacecraft, the European Space Agency's Huygens probe parachuted to a historic landing on Saturn's moon Titan on January 14. Above...

Jupiters Moons Thebe, Amalthea, and Metis
8.05.2000

The robot spacecraft Galileo in orbit around Jupiter has recently photographed the inner moons of Jupiter in greater detail than ever before. These pictures of Thebe, Amalthea, and Metis are shown to scale, and reveal details as small as three kilometers across. Amalthea, by contrast, has a total length of about 200 kilometers.

Cracks and Ridges on Europa
2.06.2002

Which way to the interstate? What appears to be a caricature of a complex highway system on Earth is actually a system of ridges and cracks on the icy surface of Jupiter's moon Europa. The distance between parallel ridges in the above photograph is typically about 1 kilometer.

Stereo Saturn
29.10.1997

Get out your red/blue glasses and launch yourself into this stereo picture of Saturn! The picture is actually composed from two images recorded weeks apart by the Voyager 2 spacecraft during its visit to the Saturnian System in August of 1981.

Mammatus Clouds over Saskatchewan
11.08.2021

When do cloud bottoms appear like bubbles? Normally, cloud bottoms are flat. This is because moist warm air that rises and cools will condense into water droplets at a specific temperature, which usually corresponds to a very specific height. As water droplets grow, an opaque cloud forms.