Ski Enceladus
23.01.2002

A small inner moon of Saturn, Enceladus is only about 500 kilometers in diameter. But the cold, distant world does reflect over 90 percent of the sunlight it receives, giving its surface about the same reflectivity as new-fallen snow.

The Sky in Motion
30.12.2008

Still need to come up with a good new year's resolution? Consider one appropriate for 2009, the International Year of Astronomy; just look up -- experience, learn, and enjoy the changing sky. This 4-minute, time-lapse video is composed from a series of 7,000 images highlighting much of what you could see.

Thunder Moon over Pisa
17.07.2017

What's wrong with this picture? If you figure it out, you may then realize where the image was taken. The oddity lies actually in one of the buildings -- it leans. The Leaning Tower of Pisa has been an iconic legend since shortly after its construction began in the year 1173.

APOD: 2023 August 22 Б The Pistachio Nebula
21.08.2023

This nebula had never been noted before. Newly discovered nebulas are usually angularly small and found by professionals using large telescopes. In contrast, the Pistachio Nebula was discovered by dedicated amateurs and, although faint, is nearly the size of the full Moon.

APOD: 2026 August 25 Б Earths Shadow Visualized with Lunar Eclipses
24.08.2026

WhatБs creating this giant hole in space? This is not a black hole Б itБs a shadow. ItБs EarthБs shadow. Since at least the time of Aristotle, people have noted that Earth's dark shadow on the Moon during a partial lunar eclipse is circular -- although never a whole circle.

Double Asteroid 90 Antiope
31.10.2000

This eight-frame animation is based on the first ever images of a double asteroid! Formerly thought to be a single enormous chunk of rock, asteroid 90 Antiope resides in the solar system's main asteroid belt between Mars and Jupiter.

Cassini Images Density Waves in Saturns Rings
5.07.2004

What causes the patterns in Saturn's rings? The Cassini spacecraft just entering orbit around Saturn has started sending back spectacular images of Saturn's immense ring system in unprecedented detail. The physical cause for many of newly resolved ring structures is not always understood.

Suiting Up for the Moon
31.03.2015

How will cows survive on the Moon? One of the most vexing questions asked about space, scientists have spent decades debating this key issue. Finally, after extensive computer modeling and over a dozen midnight milkings, engineers have designed, built, and now tested the new Lunar Grazing Module (LGM), a multi-purpose celestial bovine containment system.

Dawn of the Dish
19.07.2012

Wandering planets Venus and Jupiter were joined by an old crescent Moon near the eastern horizon on July 15. This serene southern skyview of the much anticipated predawn conjunction includes the lovely Pleiades star cluster and bright stars Aldebaran and Betelgeuse in the celestial lineup.

New Horizons
21.06.2015

In three weeks, the robotic New Horizons spacecraft will reach Pluto. As the featured video makes clear, though, humanity has been on an unprecedented epoch of robotic exploration of our Solar System's planets for the past half century.