Bright Venus
7.03.2001

Have you seen a bright evening star in the western sky lately? That's no star, that's planet Venus the second "rock" from the Sun. Blazing at -4.6 magnitude, Venus, after the Sun and Moon, is the third brightest celestial body in planet Earth's sky.

A Lucky Lunar Eclipse
3.04.1996

Tonight's full moon would normally washout the spectacle of Comet Hyakutake's lovely tail, even for those far from light polluted skies. Except that tonight comet observers are in luck - the dance of the planets calls for a total lunar eclipse! Lunar eclipses are caused when the Moon passes through the Earth's shadow.

Cratered Cliffs of Ice on Saturns Tethys
12.10.2005

The surface of Saturn's moon Tethys is riddled with icy cliffs and craters. The most detailed images ever taken of Tethys were captured late last month as the robot Cassini spacecraft swooped past the frozen ice moon.

Enceladus Looms
12.05.2011

A sunlit crescent of Saturn's moon Enceladus looms above the night side of Saturn in this dramatic image from the Cassini spacecraft. Captured on August 13, 2010 looking in a sunward direction during...

APOD: 2024 April 14 Б How a Total Solar Eclipse Ended
13.04.2024

How does a total solar eclipse end? Yes, the Moon moves out from fully blocking the Sun, but in the first few seconds of transition, interesting things appear. The first is called a diamond ring.

A Great White Spot on Rhea
30.05.2005

Why caused this great white spot on the surface of Saturn's moon Rhea? The spot was first noticed last year by the robot Cassini spacecraft now orbiting Saturn. Cassini's flyby of Rhea in April imaged in the spot in great detail.

A Lunar Corona over Turin
15.09.2019

What are those colorful rings around the Moon? A corona. Rings like this will sometimes appear when the Moon is seen through thin clouds. The effect is created by the quantum mechanical diffraction of light around individual, similarly-sized water droplets in an intervening but mostly-transparent cloud.

Quadruple Lunar Halo Over Winter Road
1.01.2022

Sometimes falling ice crystals make the atmosphere into a giant lens causing arcs and halos to appear around the Sun or Moon. One Saturday night in 2012 was just such a time near Madrid, Spain, where a winter sky displayed not only a bright Moon but four rare lunar halos.

Io in True Color
15.07.2001

The strangest moon in the Solar System is bright yellow. This picture, showing Io's true colors, was taken in 1999 July by the Galileo spacecraft currently orbiting Jupiter. Io's colors derive from sulfur and molten silicate rock. The unusual surface of Io is kept very young by its system of active volcanoes.

Shadow at the Lunar South Pole
27.11.1995

In 1994, the space probe Clementine spent 70 days in lunar orbit mapping the Moon's surface. Shown above is a dramatically detailed composite view centered on the Moon's South Pole constructed from 1500 Clementine images.