A Sun Halo Over Tennessee
8.03.2005

Sometimes it looks like the Sun is being viewed through a large lens. In the above case, however, there are actually millions of lenses: ice crystals. As water freezes in the upper atmosphere, small, flat, six-sided, ice crystals might be formed.

Tyrrhenian Sea and Solstice Sky
21.12.2007

Today the Solstice occurs at 0608 Universal Time, the Sun reaching its southernmost declination in planet Earth's sky. Of course, the December Solstice marks the beginning of winter in the northern hemisphere and summer in the south.

Clouds, Comet, and Crescent Moon
14.03.2013

In silhouette against the colorful evening twilight glow, clouds part in this much anticipated magic moment. The scene captures naked-eye Comet PanSTARRS peeking into northern hemisphere skies on March 12. The comet stands over the western horizon after sunset, joined by the thin, flattened crescent of a day old Moon.

Smile in the Sky
4.12.2008

At sunset, Monday's western sky showed off stunning colors and dramatic clouds reflected in Brisbane Water on the Central Coast of New South Wales, Australia. It also featured the remarkable conjunction of the crescent Moon, Venus, and Jupiter forming a twilight smiley face.

Noctilucent Clouds over Paris Fireworks
9.07.2018

It's northern noctilucent cloud season -- perhaps a time to celebrate! Composed of small ice crystals forming only during specific conditions in the upper atmosphere, noctilucent clouds may become visible at sunset during late summer when illuminated by sunlight from below.

Mars Rising Behind Poodle Rock
13.08.2003

Have you seen Mars lately? As Earth and Mars near their closest approach in nearly 60,000 years on August 27, the red planet has begun to appear dramatically bright and show interesting details through telescopes and binoculars. Although not yet visible at sunset, Mars can be seen rising increasingly earlier in the evening.

A Glimpse of CLIMSO
25.11.2011

A tantalizing glimpse inside this dome was captured after sunset at the mountain top Pic Du Midi Observatory in the French Pyrenees. But while most are just beginning their work at sunset, this observatory's day was done.

The Magnificent Tail of Comet McNaught
5.12.2009

Comet McNaught, the Great Comet of 2007, was the brightest comet of the last 40 years. Its spectacular tail spread across the sky and was breathtaking to behold from dark locations for many Southern Hemisphere observers.

Highlights of the North Autumn Sky
24.09.2018

What can you see in the night sky this season? The featured graphic gives a few highlights for Earth's northern hemisphere. Viewed as a clock face centered at the bottom, early (northern) autumn sky events fan out toward the left, while late autumn events are projected toward the right.

Red Moon Rising
16.12.2011

This surreal, wintry scene is a composite picture recorded on December 10 as the Moon rose behind the Zagros Mountains of Iran. A total lunar eclipse was already in progress. The image combines nearly 500 successive frames taken over 1.5 hours beginning in twilight as the eclipsed Moon steadily climbed above the rugged landscape.