APOD: 2025 September 1 Б Callisto: Dirty Battered Iceball
1.09.2025

Its surface is the most densely cratered in the Solar System -- but what's inside? Jupiter's moon Callisto is a battered ball of dirty ice that is larger than the planet Mercury.

APOD: 2023 July 18 Б Milky Way above La Palma Observatory
18.07.2023

What's happening in the night sky? To help find out, telescopes all over the globe will be pointing into deep space. Investigations will include trying to understand the early universe, finding and tracking Earth-menacing asteroids, searching for planets that might contain extra-terrestrial life, and monitoring stars to help better understand our Sun.

The Surface of Europa
19.05.2016

An enhanced-color view, this image covers a 350 by 750 kilometer swath across the surface of Jupiter's tantalizing moon Europa. The close-up combines high-resolution image data with lower resolution color data from observations made in 1998 by the Galileo spacecraft.

Kepler s House in Linz
15.05.2018

Four hundred years ago today (May 15, 1618) Johannes Kepler discovered the simple mathematical rule governing the orbits of the solar system's planets, now recognized as Kepler's Third Law of planetary motion.

Cassini Spacecraft Crosses Saturns Ring Plane
23.02.2014

If this is Saturn, where are the rings? When Saturn's "appendages" disappeared in 1612, Galileo did not understand why. Later that century, it became understood that Saturn's unusual protrusions were rings and that when the Earth crosses the ring plane, the edge-on rings will appear to disappear.

Jupiter and Ring in Infrared from Webb
20.07.2022

Why does Jupiter have rings? Jupiter's main ring was discovered in 1979 by NASA's passing Voyager 1 spacecraft, but its origin was then a mystery. Data from NASA's Galileo spacecraft that...

Asteroids
13.03.1998

No asteroid or comet is known to be on a collision course with Earth. The asteroid designated 1997 XF11 had been predicted to come uncomfortably close, but new estimates place its passing beyond the orbit of the Moon. This earth-approaching asteroid was discovered by SpaceWatch astronomer Jim Scotti in December of last year.

Two Views, Two Crescents
11.11.2010

Venus rose in a glowing dawn sky on November 5th, just before the Sun. For early morning risers, its brilliant crescent phase was best appreciated with binoculars or a small telescope. On that...

APOD: 2025 April 2 Б Jupiter and Ring in Infrared from Webb
2.04.2025

Why does Jupiter have rings? Jupiter's main ring was discovered in 1979 by NASA's passing Voyager 1 spacecraft, but its origin was then a mystery. Data from NASA's Galileo spacecraft that...

Messier 45: The Daughters of Atlas and Pleione
5.01.2023

Hurtling through a cosmic dust cloud a mere 400 light-years away, the lovely Pleiades or Seven Sisters open star cluster is well-known for its striking blue reflection nebulae. It lies in the night sky toward the constellation Taurus and the Orion Arm of our Milky Way galaxy.