Eight Planets and New Solar System Designations
28.08.2006

How many planets are in the Solar System? This popular question now has a new formal answer according the International Astronomical Union (IAU): eight. Last week, the IAU voted on a new definition for planet and Pluto did not make the cut.

Southern Neptune
10.07.1999

Neptune, the Solar System's outermost gas giant planet, is 30 times farther from the Sun than Earth. Twelve years after a 1977 launch, Voyager 2 flew by Neptune and found surprising activity on a planet that receives only 3 percent as much sunlight as Jupiter.

AR 2192: Giant on the Sun
24.10.2014

As you (safely!) watched the progress of yesterday's partial solar eclipse, you probably also spotted a giant sunspot group. Captured in this sharp telescopic image from October 22nd the complex AR 2192 is beautiful to see, a sprawling solar active region comparable in size to the diameter of Jupiter.

Night Sky Reflections from the Worlds Largest Mirror
21.10.2019

What's being reflected in the world's largest mirror? Stars, galaxies, and a planet. Many of these stars are confined to the grand arch that runs across the image, an arch that is the central plane of our home Milky Way Galaxy. Inside the arch is another galaxy -- the neighboring Large Magellanic Cloud (LMC).

Irregular Moons Discovered Around Uranus
2.11.1997

Where did these two irregular moons of Uranus originate? Last week two previously undiscovered moons of the distant gas planet were confirmed, the first in irregular orbits. All fifteen previously known moons of Uranus are 'regular', circling near the planet's equator. Most of these were discovered by the passing Voyager 2 spacecraft in 1986.

Galileo s Europa Remastered
26.11.2014

Looping through the Jovian system in the late 1990s, the Galileo spacecraft recorded stunning views of Europa and uncovered evidence that the moon's icy surface likely hides a deep, global ocean. Galileo...

Galileo s Europa Remastered
28.11.2019

Looping through the Jovian system in the late 1990s, the Galileo spacecraft recorded stunning views of Europa and uncovered evidence that the moon's icy surface likely hides a deep, global ocean. Galileo...

Perseid Rain
14.08.2021

Comet dust rained down on planet Earth last week, streaking through dark skies in the annual Perseid meteor shower. The featured picture is a composite of many images taken from the same location over the peak night of the Perseids.

Late Night Vallentuna
14.08.2024

Bright Mars and even brighter Jupiter are in close conjunction just above the pine trees in this post-midnight skyscape from Vallentuna, Sweden. Taken on August 12 during a geomagnetic storm, the snapshot records the glow of aurora borealis or northern lights, beaming from the left side of the frame.

Crescent Europa
24.02.2002

Although the phase of this moon might appear familiar, the moon itself might not. In fact, this crescent shows part of Jupiter's moon Europa. The passing robot spacecraft Voyager 2 captured this image in 1979.