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.

Comet Hale-Bopp Passes M14
12.11.1996

Comet Hale-Bopp continues its slow trek across the night sky, and can now be seen superposed near the bright globular cluster M14. Will Comet Hale-Bopp become as bright in early 1997 as Comet Hyakutake did in early 1996? It is still too early to tell.

Night Lightning on Jupiter
16.12.1997

Why is there lightning on Jupiter? Lightning is a sudden rush of electrically charged particles from one location to another. To create lightning, charges must first separate inside a cloud. On Earth, drafts of colliding ice and water droplets usually create this charge separation, but what happens on Jupiter?

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.

Interstellar Dust Bunnies of NGC 891
19.09.1999

What is going on in NGC 891? This galaxy appeared previously to be very similar to our own Milky Way Galaxy: a spiral galaxy seen nearly edge-on. However, recent high-resolution images of NGC 891's dust show unusual filamentary patterns extending well away from its Galactic disk.

Comet Between Fireworks and Lightning
5.07.2008

Sometimes the sky itself is the best show in town. Last January, people from Perth, Australia gathered on a local beach to watch a sky light up with delights near and far. Nearby, fireworks exploded as part of Australia Day celebrations. On the far right, lightning from a thunderstorm flashed in the distance.

A Sun Pillar Over North Carolina
15.12.2008

Have you ever seen a sun pillar? When the air is cold and the Sun is rising or setting, falling ice crystals can reflect sunlight and create an unusual column of light. Ice sometimes forms flat, six-sided shaped crystals as it falls from high-level clouds.

The Antennae Galaxies in Collision
18.07.2010

Two galaxies are squaring off in Corvus and here are the latest pictures. But when two galaxies collide, the stars that compose them usually do not. That's because galaxies are mostly empty space and, however bright, stars only take up only a small amount of that space.

Moon and Earth from Chang e 5 T1
3.11.2014

Described at times as a big blue marble, from some vantage points Earth looks more like a small blue marble. Such was the case in this iconic image of the Earth and Moon system taken by the Chang'e 5-T1 mission last week.

Auroras and Star Trails over Iceland
18.05.2015

It was one of the quietest nights of aurora in weeks. Even so, in northern- Iceland during last November, faint auroras lit up the sky every clear night. The featured 360-degree panorama is the digital fusion of four wide-angle cameras each simultaneously taking 101 shots over 42 minutes.