The Galactic Center Radio Arc
27.04.2008

What causes this unusual structure near the center of our Galaxy? The long parallel rays slanting across the top of the above radio image are known collectively as the Galactic Center Radio Arc and jut straight out from the Galactic plane.

Retrograde Mars
13.06.2010

Why would Mars appear to move backwards? Most of the time, the apparent motion of Mars in Earth's sky is in one direction, slow but steady in front of the far distant stars. About every two years, however, the Earth passes Mars as they orbit around the Sun.

Iridescent Cloud Edge Over Colorado
28.10.2014

Sometimes your eclipse viewing goes bad in an interesting way. While watching and photographing last Thursday's partial solar eclipse, a popular astronomy blogger suffered through long periods of clouds blocking the Sun. Unexpectedly, however, a nearby cloud began to show a rare effect: iridescence.

Saturn in Infrared from Cassini
2.04.2017

Many details of Saturn appear clearly in infrared light. Bands of clouds show great structure, including long stretching storms. Also quite striking in infrared is the unusual hexagonal cloud pattern surrounding Saturn's North Pole. Each side of the dark hexagon spans roughly the width of our Earth.

A Waterspout in Florida
16.05.2020

What's happening over the water? Pictured here is one of the better images yet recorded of a waterspout, a type of tornado that occurs over water. Waterspouts are spinning columns of rising moist air that typically form over warm water.

Northern Lights, West Virginia
11.10.2024

A gravel country lane gently winds through this colorful rural night skyscape. Captured from Monroe County in southern West Virginia on the evening of October 10, the starry sky above is a familiar sight. Shimmering curtains of aurora borealis or northern lights definitely do not make regular appearances here, though.

NGC 1850: Gas Clouds and Star Clusters
23.12.2000

There's nothing like it in our own Galaxy. Globular clusters as young as NGC 1850 don't exist here. Globular clusters only 40 millions of years old can still be found in the neighboring LMC galaxy, though, but perhaps none so unusual as NGC 1850.

Spiral Galaxies in Collision
8.11.1999

Billions of years from now, only one of these two galaxies will remain. Until then, spiral galaxies NGC 2207 and IC 2163 will slowly pull each other apart, creating tides of matter, sheets of shocked gas, lanes of dark dust, bursts of star formation, and streams of cast-away stars.

The Surface of Titan
4.08.1999

If sailing the hydrocarbon seas of Titan, beware of gasoline rain. Such might be a travel advisory issued next millennium for adventurers visiting Titan, the largest moon of Saturn. Images of Titan's surface were released last week from the Keck 10-meter telescope featuring the finest details yet resolved.

Shadow of a Martian Robot
29.06.2008

What if you saw your shadow on Mars and it wasn't human? Then you might be the Opportunity rover currently exploring Mars. Opportunity and sister robot Spirit have been probing the red planet since early 2004, finding evidence of ancient water, and sending breathtaking images across the inner Solar System.