Crescent Saturn
23.10.2007

Saturn never shows a crescent phase -- from Earth. But when viewed from beyond, the majestic giant planet can show an unfamiliar diminutive sliver. This image of crescent Saturn in natural color was taken by the robotic Cassini spacecraft in May.

M13: The Great Globular Cluster in Hercules
27.05.2010

In 1716, English astronomer Edmond Halley noted, "This is but a little Patch, but it shews it self to the naked Eye, when the Sky is serene and the Moon absent." Of course...

Unusual Rocks near Pahrump Hills on Mars
29.09.2014

How did these Martian rocks form? As the robotic Curiosity rover has approached Pahrump Hills on Mars, it has seen an interesting and textured landscape dotted by some unusual rocks. The featured image shows a curiously round rock spanning about two centimeters across.

Dark Craters and Bright Spots Revealed on Asteroid Ceres
17.02.2015

What are those bright spots on asteroid Ceres? As the robotic spacecraft Dawn approaches the largest asteroid in the asteroid belt, the puzzle only deepens. Sharper new images taken last week and released yesterday...

A Colorful Solar Corona over the Himalayas
10.01.2016

What are those colorful rings around the Sun? A corona visible only to Earth observers in the right place at the right time. Rings like this will sometimes appear when the Sun or Moon is seen through thin clouds.

A Sagittarius Triplet
25.04.2021

These three bright nebulae are often featured on telescopic tours of the constellation Sagittarius and the crowded starfields of the central Milky Way. In fact, 18th century cosmic tourist Charles Messier cataloged two of them; M8, the large nebula below and right of center, and colorful M20 near the top of the frame.

The Galaxy Between Two Friends
5.11.2021

On an August night two friends enjoyed this view after a day's hike on the Plateau d'Emparis in the French Alps. At 2400 meters altitude the sky was clear. Light from a setting moon illuminates the foreground captured in the simple vertical panorama of images.

APOD: 2025 August 12 Б Perseids from Perseus
11.08.2025

Where are all of these meteors coming from? In terms of direction on the sky, the pointed answer is the constellation of Perseus. That is why the meteor shower that peaks tonight is known as the Perseids -- the meteors all appear to come from a radiant toward Perseus.

Mariner's Mercury
16.12.1996

Mercury, the closest planet to the Sun, remains the most mysterious of the Solar System's inner planets. Hiding in the Sun's glare it is a difficult target for Earth bound observers.

Big Blue Marble Earth
26.04.2003

This reconstructed digital portrait of our planet is reminiscent of the Apollo-era pictures of the "big blue marble" Earth from space. To create it, researchers at Goddard Space Flight Center's Laboratory for Atmospheres...