APOD: 2025 December 22 Б Sunset Solstice over Stonehenge
22.12.2025

Yesterday the Sun reached its southernmost point in planet Earth's sky. Called a solstice, many cultures mark yesterday's date as a change of seasons -- from autumn to winter in Earth's Northern Hemisphere and from spring to summer in Earth's Southern Hemisphere.

Crescents of Venus
26.08.2023

Just as the Moon goes through phases, Venus' visible sunlit hemisphere waxes and wanes. This sequence of telescopic images illustrates the steady changes for Venus during its recent 2023 apparition as our evening star. Gliding along its interior orbit between Earth and Sun, Venus grows larger during that period because it is approaching planet Earth.

A Solar Ballet
15.01.2013

Sometimes, the Sun itself seems to dance. On just this past New Year's Eve, for example, NASA's Sun-orbiting Solar Dynamic Observatory spacecraft imaged an impressive prominence erupting from the Sun's surface. The dramatic explosion was captured in ultraviolet light in the above time lapse video covering four hours.

Sunspots: Magnetic Depressions
13.01.1997

Our Sun has spots! These spots appear dark in photographs like the one above, but in fact sunspots are quite bright - they are just dark compared to the rest of the Sun. Sunspots are about the size of the Earth and frequently occur in groups, as shown above.

Shuttle Plume Shadow Points to the Moon
27.11.2011

Why would the shadow of a space shuttle launch plume point toward the Moon? In early 2001 during a launch of Atlantis, the Sun, Earth, Moon, and rocket were all properly aligned for this photogenic coincidence.

Touran Sunrise
23.03.2007

Clouds covered the eastern horizon on Monday, when the Sun rose over the expansive Touran Wildlife Reserve in northeastern Iran. Of course, on that day the Moon rose with the Sun, creating a widely enjoyed partial solar eclipse.

DIA Sunrise
14.11.2009

What's 93 million miles away and still hurts your eyes when you look at it? The answer is not the Denver International Airport, known to some travelers as DIA. But DIA does appear in dramatic silhouette in the foreground of this telephoto image.

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.

Moon Pi and Mountain Shadow
14.03.2024

What phase of the Moon is 3.14 radians from the Sun? The Full Moon, of course. Even though the Moon might look full for several days, the Moon is truly at its full phase when it is Pi radians (aka 180 degrees) from the Sun in ecliptic longitude.

Perihelion to Aphelion
9.01.2020

Perihelion for 2020, the point in Earth's elliptical orbit when it is closest to the Sun, occurred on January 5th. The distance from the Sun doesn't determine the seasons, though. Those...