A Proton Aurora
17.12.2003

What are auroras made out of? Most auroras are caused by the solar wind exciting electrons that are funneled down the Earth's magnetic field. These electrons strike air molecules, liberating other electrons that glow when re-acquired.

Jules Verne in Orbit
5.04.2008

The bright edge of planet Earth fades into the darkness of space in the background of this view of Jules Verne on an extraordinary voyage. Snapped last Monday, the picture shows the European Space...

Circles in the Sky
16.05.2008

Gazing skyward on a sunny day in May, photographer Jean-Marc Lecleire captured this engaging display of ice halos forming complete circles in the sky. Recorded with a fish-eye lens from a spot near the grand Château de Chambord in France, the picture looks straight up, spanning almost 180 degrees from horizon to horizon.

Dim World, Dark Nebula
8.07.2010

Dim, distant, dwarf planet Pluto can be hard to spot, especially in recent months as it wanders through the crowded starfields of Sagittarius and the central Milky Way. But fortunately for backyard Pluto hunters, it crossed in front of a dark nebula in early July.

Echoes from the Depths of a Red Giant Star
8.04.2011

A journey to the center of a red giant star is very firmly in the realm of science fiction. But the science of asteroseismology can explore the conditions there. The technique is to time the small variations in a star's brightness measured by the planet hunting Kepler spacecraft.

Curiosity Inspects Mt Remarkable on Mars
7.05.2014

What has the Curiosity rover come across on Mars? Dubbed Mount Remarkable, the rolling robot has chanced upon this notable 5-meter tall mound during its continuing journey around and, eventually, up 5.5-kilometer high Mt. Sharp.

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.

Cataclysmic Dawn
10.01.2015

Will this dawn bring another nova? Such dilemmas might be pondered one day by future humans living on a planet orbiting a cataclysmic variable binary star system. Cataclysmic variables involve gas falling from a large star onto an accretion disk surrounding a massive but compact white dwarf star.

Saturn, Tethys, Rings, and Shadows
5.04.2015

Seen from ice moon Tethys, rings and shadows would display fantastic views of the Saturnian system. Haven't dropped in on Tethys lately? Then this gorgeous ringscape from the Cassini spacecraft will have to do for now.

Comet PanSTARRS in the Southern Fish
17.06.2016

Now approaching our fair planet this Comet PanSTARRS (C/2013 X1) will come closest on June 21-22, a mere 5.3 light-minutes away. By then its appearance low in northern hemisphere predawn skies (high in the south), will be affected by the light of a nearly Full Moon, though.