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.

A View to the Sunset
31.05.2008

Each day on planet Earth can have a dramatic ending as the Sun sets below the colorful western horizon. Often inspiring, or offering a moment for contemplation, a sunset is perhaps the single most photographed celestial event. Did you recognize this as a picture of one?

Sunset Over Gusev Crater
20.06.2005

What would it be like to see a sunset on Mars? To help find out, the robotic rover Spirit was deployed last month to park and serenely watch the Sun dip below the distant lip of Gusev crater. It was a tough job, but some robot had to do it.

The Belt of Venus
10.11.1999

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.

Sunset with Hale-Bopp at Keck
5.05.1997

A famous star cluster and observatory highlight this picture of Comet Hale-Bopp. Taken last week from the observatory summit of Hawaii's Mauna Kea Volcano, the dome of the new 10-meter Keck II telescope appears silhouetted on the lower left.

Noctilucent Clouds Over Germany
24.06.2009

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.

A Flock of Stars
6.09.2008

Only a few stars can be found within ten light-years of our lonely Sun, situated near an outer spiral arm of the Milky Way galaxy. But if the Sun were found within one of our galaxy's star clusters, thousands of stars might occupy a similar space.