Leonid Sunrise
16.11.2000

Such beautiful things begin as grains of sand. Locked in an oyster a granule grows into an iridescent pearl, lustrous and lovely to behold. While hurtling through the atmosphere at 70 kilometers per second, a cosmic sand grain becomes an awe-inspiring meteor, its transient beauty displayed for any who care to watch.

A Fog Bow Over Ocean Beach
29.05.2008

What is that white arch over the water? What is being seen is a fogbow, a reflection of sunlight by water drops similar to a rainbow but without the colors. The fog itself is not confined to an arch -- the fog is mostly transparent but relatively uniform.

Leonid over Mono Lake
18.11.2009

Eerie spires of rock rise from shore of Mono Lake in the foreground of this early morning skyscape. The salty, mineral-laden lake is located in California's eastern Sierra Nevada mountain range and the spindly rock formations are naturally formed limestone towers called tufa.

A Sailing Stone in Death Valley
22.02.2012

How did this big rock end up on this strange terrain? One of the more unusual places here on Earth occurs inside Death Valley, California, USA. There a dried lakebed named Racetrack Playa exists that is almost perfectly flat, with the odd exception of some very large stones, one of which is pictured above.

APOD: 2025 June 18 Б Space Station Silhouette on the Moon
17.06.2025

What's that unusual spot on the Moon? It's the International Space Station. Using precise timing, the Earth-orbiting space platform was photographed in front of a partially lit gibbous Moon in 2019. The featured image was taken from Palo Alto, California, USA with an exposure time of only 1/667 of a second.

APOD: 2023 August 21 Б Introducing Comet Nishimura
20.08.2023

Will Comet Nishimura become visible to the unaided eye? Given the unpredictability of comets, no one can say for sure, but it currently seems like a good bet. The comet was discovered only ten days ago by Hideo Nishimura during 30-second exposures with a standard digital camera.

The Belt of Venus over the Valley of the Moon
23.07.2006

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.

Annular Solar Eclipse
19.05.2012

Tomorrow, May 20, the Moon's shadow will race across planet Earth. Observers within the 240-300 kilometer wide shadow track will be able to witness an annular solar eclipse as the Moon's apparent size is presently too small to completely cover the Sun.

APOD: 2023 May 24 Б Observatory Aligned with Moon Occulting Jupiter
23.05.2023

Sometimes we witness the Moon moving directly in front of -- called occulting -- one of the planets in our Solar System. Earlier this month that planet was Jupiter. Captured here was the moment when Jupiter re-appeared from behind the surface of our Moon.

Zodiacal Light before Dawn
11.09.2014

You might not guess it, but sunrise was still hours away when this nightscape was taken, a view along the eastern horizon from a remote location in Chile's Atacama desert. Stretching high into...