Mimas in Saturnlight
30.07.2021

Peering from the shadows, the Saturn-facing hemisphere of Mimas lies in near darkness alongside a dramatic sunlit crescent. The mosaic was captured near the Cassini spacecraft's final close approach on January 30, 2017. Cassini's camera was pointed in a nearly sunward direction only 45,000 kilometers from Mimas.

Mercury: A Cratered Inferno
30.11.1997

Mercury's surface looks similar to our Moon's. Each is heavily cratered and made of rock. Mercury's diameter is about 4800 km, while the Moon's is slightly less at about 3500 km (compared with about 12,700 km for the Earth). But Mercury is unique in many ways.

A Giant Starspot on HD 12545
2.11.2003

What could cause a star to have such a large spot? Our Sun itself frequently has sunspots, relatively cool dark magnetic depressions that move across its surface. HD 12545, however, exhibits the largest starspots yet observed.

Equinox Earth
28.09.2013

From a geostationary orbit 36,000 kilometers above the equator, Russian meteorological satellite Elektro-L takes high-resolution images our fair planet every 30 minutes. But only twice a year, during an Equinox, can it capture an image like this one, showing an entire hemisphere bathed in sunlight.

Perihelion to Aphelion
8.07.2021

Aphelion for 2021 occurred on July 5th. That's the point in Earth's elliptical orbit when it is farthest from the Sun. Of course, the distance from the Sun doesn't determine the seasons.

APOD: 2024 January 22 Б Shadows of Mountain and Moon
22.01.2024

Can the Moon and a mountain really cast similar shadows? Yes, but the division between light and dark does not have to be aligned. Pictured, a quarter moon was captured above the mountain Grivola in Italy in early October of 2022.

Sunspot Region 30
18.07.2002

The solar active region designated number 0030 is now appearing on the visible hemisphere of the closest star. Dwarfed by the Sun's disk, the group of sunspots which make up region 30 actually cover an enormous area -- nearly 10 times the size of Earth.

Lunar Farside from Apollo 11
12.03.2003

The far side of the Moon is rough and filled with craters. By comparison, the near side of the Moon, the side we always see, is relatively smooth. Since the Moon is rotation locked to always point the same side toward Earth, humanity has only glimpsed the lunar farside recently -- last century.

Star Trails at Dawn
8.12.2007

Just fix your camera to a tripod and you too can make an image of graceful trails traced by the stars as planet Earth rotates on its axis. Made on September 14 from Montlaux...

Prominences and Filaments on the Active Sun
15.06.2024

This colorized and sharpened image of the Sun is composed of frames recording emission from hydrogen atoms in the solar chromosphere on May 15. Approaching the maximum of solar cycle 25, a multitude of active regions and twisting, snake-like solar filaments are seen to sprawl across the surface of the active Sun.