Lunar Dust and Duct Tape
14.12.2022

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

Lunar Dust and Duct Tape
28.03.2025

Why is the Moon so dusty? On Earth, rocks are weathered by wind and water, creating soil and sand. On the Moon, eons of constant micrometeorite bombardment have blasted away at the rocky surface creating a layer of powdery lunar soil or regolith.

Full Moon, Full Mars
15.12.2022

On December 8 a full Moon and a full Mars were close, both bright and opposite the Sun in planet Earth's sky. In fact Mars was occulted, passing behind the Moon when viewed from some locations across Europe and North America.

Rima Hyginus
22.02.2025

Rima Hyginus is a spectacular fissure, some 220 kilometers long, found near the center of the lunar near side. Easy to spot in telescopic views of the Moon, it stretches top left to bottom right across this lunar closeup. The image was made with exaggerated colors that reflect the mineral composition of the lunar soil.

Moon Pi and Mountain Shadow
14.03.2025

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.

Lunar Dust and Duct Tape
17.04.2004

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.

Lunar Dust and Duct Tape
10.11.2001

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.

Mimas: Small Moon with a Big Crater
25.04.1999

Mimas is one of the smaller moons of Saturn but shows one of the largest impact craters. In fact, if the impact had been much greater, it would have disrupted the entire satellite. The large crater has been named Herschel after the 1789 discoverer of Mimas, Sir William Herschel.

APOD: 2025 November 12 Б A Super Lunar Corona
12.11.2025

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 diffraction of light around individual, similarly-sized water droplets in an intervening but mostly transparent cloud.

A Daylight Eclipse of Venus
20.06.2007

Something was about to happen. Just two days ago, two of the three celestial objects easily visible during the day appeared to collide. But actually, Earth's Moon passed well in front of the distant planet Venus. The occultation was caught from Switzerland in the hours before sunset.