Sunset, Moonset
7.01.2011

Seen from central and northern Asia, the Sun and New Moon set together on January 4, in a partial solar eclipse. Close to its maximum phase, the eclipse is captured near the moment of sunset in this wintry scene from the bank of the Berd River near Novosibirsk, Siberia, Russia.

Mammatus Clouds Over Olympic Valley
20.02.2011

What's happened to these clouds? 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.

Noctilucent Clouds Over Edmonton
20.07.2011

Sometimes it's night on the ground but day in the air. As the Earth rotates to eclipse the Sun, sunset rises up from the ground. Therefore, at sunset on the ground, sunlight still shines on clouds above.

Sunset from the International Space Station
23.06.2010

What are these strange color bands being seen from the International Space Station? The Sun setting through Earth's atmosphere. Pictured above, a sunset captured last month by the ISS's Expedition 23 crew shows in vivid detail many layers of the Earth's thin atmosphere.

Sunspot at Sunset
13.07.2013

Reddened rays of the setting Sun flooded the skies over Cedar Creek Lake, southeast of Dallas, Texas, planet Earth on July 6th. And while sunsets may be the most watched celestial event, this one even offered something extra.

A Solstice Sunset Self Portrait
21.06.2013

Today, the solstice is at 05:04 Universal Time, the Sun reaching the northernmost declination in its yearly journey through planet Earth's sky. A June solstice marks the astronomical beginning of summer in the northern hemisphere and winter in the south.

Mercury on the Horizon
19.02.2013

Have you ever seen the planet Mercury? Because Mercury orbits so close to the Sun, it never wanders far from the Sun in Earth's sky. If trailing the Sun, Mercury will be visible low on the horizon for only a short while after sunset.

Four Planet Sunset
13.06.2013

You can see four planets in this serene sunset image, created from a series of stacked digital exposures captured near dusk on May 25. The composite picture follows the trail of three of them...

The Belt of Venus Over Mercedes Argentina
7.02.2012

Although you've surely seen it, you might not have noticed it. During a cloudless twilight, just before sunrise or after sunset, part of the atmosphere above the horizon appears slightly off-color, slightly pink or orange.

Sunset: Planet Earth
20.03.2008

Today, the Sun crosses the celestial equator heading north at 0548 UT. Known as the equinox, the geocentric astronomical event marks the first day of spring in the northern hemisphere and autumn in the south.