Total Eclipse of the Active Sun
20.06.2001

A total eclipse of the Sun is that special geocentric celestial event where the Moon passes exactly in front of the solar disk. During a fleeting few minutes of totality, fortunate earthdwellers located within...

Lunar Dust and Duct Tape
1.05.1999

Why is the Moon dusty? On Earth, rocks are weathered by wind and water, creating soil and sand. On the Moon, the long history of micrometeorite bombardment has blasted away at the rocky surface creating a layer of powdery lunar soil or regolith. This lunar regolith could be a scientific and industrial bonanza.

The Ecliptic Plane
14.10.2000

The Plane of the Ecliptic is well illustrated in this picture from the 1994 lunar prospecting Clementine spacecraft. Clementine's star tracker camera image reveals (from right to left) the Moon lit by Earthshine, the Sun's corona rising over the Moon's dark limb, and the planets Saturn, Mars, and Mercury.

Huygens Images Titan s Surface
15.01.2005

After a seven year interplanetary voyage on board the the Cassini spacecraft, the European Space Agency's Huygens probe parachuted to a historic landing on Saturn's moon Titan on January 14. Above...

Artemis 1: Flight Day 13
30.11.2023

On flight day 13 (November 28, 2022) of the Artemis I mission, the Orion spacecraft reached its maximum distance from its home world. Over 430,000 kilometers from Earth in a distant retrograde orbit, Orion surpassed the record for most distant spacecraft designed to carry humans.

Stickney Crater
7.11.2009

Stickney Crater, the largest crater on the martian moon Phobos, is named for Chloe Angeline Stickney Hall, mathematician and wife of astronomer Asaph Hall. Asaph Hall discovered both the Red Planet's moons in 1877.

Hamlet of Oberon
31.01.1998

What's in a name? Since 1919, the International Astronomical Union has been charged with the task of establishing "conventional" nomenclature for planets, satellites, and surface features. For the remote Uranian system of moons, namesakes from Shakespearean works have been chosen.

Eclipse with Lighthouse
10.03.2007

A red Moon rose over Cape Cod, Massachusetts, USA on March 3rd, immersed in Earth's shadow near the total phase of a lunar eclipse. This serene portrait of the eclipsed Moon in a dark blue twilight sky also features the Highland Lighthouse (aka Cape Cod lighthouse), another more locally familiar beacon in the night.

APOD: 2024 March 24 Б Looking Back at an Eclipsed Earth
24.03.2024

Here is what the Earth looks like during a solar eclipse. The shadow of the Moon can be seen darkening part of Earth. This shadow moved across the Earth at nearly 2000 kilometers per hour.

APOD: 2024 July 9 Б Noctilucent Clouds over Florida
9.07.2024

These clouds are doubly unusual. First, they are rare noctilucent clouds, meaning that they are visible at night -- but only just before sunrise or just after sunset. Second, the source of these noctilucent clouds is actually known.