APOD: 2024 January 22 Б Shadows of Mountain and Moon
22.01.2024

Can the Moon and a mountain really cast similar shadows? Yes, but the division between light and dark does not have to be aligned. Pictured, a quarter moon was captured above the mountain Grivola in Italy in early October of 2022.

APOD: 2025 February 17 Б SpaceX Rocket Launch Plume over California
17.02.2025

What's happened to the sky? Last Monday, the photogenic launch plume from a SpaceX rocket launch created quite a spectacle over parts of southern California and Arizona. Looking at times like a giant...

Methane Earth
12.02.2002

Can you help in reducing this blanket of methane gas that is warming up our Earth? Recent evidence holds that methane (CH₄) is second only to carbon dioxide (CO₂) in creating a warming greenhouse effect but is easier to control.

Sunspot Region 30
18.07.2002

The solar active region designated number 0030 is now appearing on the visible hemisphere of the closest star. Dwarfed by the Sun's disk, the group of sunspots which make up region 30 actually cover an enormous area -- nearly 10 times the size of Earth.

Moons and Bright Mars
1.08.2003

In this serene view, the moons of Earth along with the bright planet Mars shine above the city of Turku near the southwestern tip of Finland. Of course Earth's large natural satellite, the Moon, at a distance of 400,000 kilometers, is by far the brightest object in this sky.

The Long Shadow of the Moon
27.11.2003

The long shadow of the Moon fell across the continent of Antarctica on November 23rd, during the second total solar eclipse of 2003. In this view from orbit, based on data from the MODIS instrument on board the Earth observing Aqua satellite, the Moon's shadow stretches for almost 500 kilometers.

Jupiter Swallows Comet Shoemaker Levy 9
4.08.1998

What happens when a comet encounters a planet? If the planet has a rocky surface, a huge impact feature will form. A giant planet like Jupiter, however, is mostly gas. When Comet Shoemaker-Levy 9 struck Jupiter in 1994, each piece was swallowed into the vast Jovian atmosphere.

The M7 Open Star Cluster in Scorpius
6.04.2005

M7 is one of the most prominent open clusters of stars on the sky. The cluster, dominated by bright blue stars, can be seen with the naked eye in a dark sky in the tail of the constellation of Scorpius.

Eclipsed Moon Rising Over England
11.09.2006

Last Thursday, part of our Moon turned dark. The cause, this time, was not a partial lunar phase -- the Moon was full -- but rather that part of the Moon went into Earth's shadow.

3D Mercury Transit
25.11.2006

Mercury is now visible shortly before dawn, the brightest "star" just above the eastern horizon. But almost two weeks ago Mercury actually crossed the face of the Sun for the second time in the 21st century.