A Cerro Tololo Sky
13.03.2004

High atop a Chilean mountain lies one of the premier observatories of the southern sky: the Cerro Tololo Inter-American Observatory (CTIO). Pictured above is the dome surrounding one of the site's best known instruments, the 4-meter Blanco Telescope.

Warped Sky: Star Trails Panorama
13.06.2007

What's happened to the sky? A time warp, of sorts, and a digital space warp too. The time warp occurs because the above image captured in a single frame a four hour exposure of the night sky. Prominent and picturesque star trails are visible.

A Western Sky at Twilight
1.05.2004

On April 23rd, the Moon along with planets Saturn, Mars, and Venus (and planet Earth of course ...) were all visible in the west at twilight, captured here from a site near Saylorvillle Lake north of Des Moines, Iowa, USA.

Earth, Clouds, Sky, Comet
3.04.1997

Does a comet's dust tail always orbit behind it? Since comets rotate, they shed gas and dust in all directions equally. Small ice and dust particles expelled by the comet, however, are literally pushed around by sunlight. The smaller the particle, the greater the effect.

Contemplating the Sky
8.08.2004

Have you contemplated your sky recently? This week will be a good one for midnight meditators at many northerly locations as meteors from the Perseid meteor shower will frequently streaked through. The Perseid meteor shower has slowly been building to a crescendo and should peak on the nights of August 11 and 12.

Meteor in the Desert Sky
11.12.2010

Created as planet Earth sweeps through dusty debris from mysterious, asteroid-like, 3200 Phaethon, the annual Geminid Meteor Shower should be the best meteor shower of the year. The Geminids are predicted to peak on the night of December 13/14, but you can start watching for Geminid meteors this weekend.

An Airglow Fan from Lake to Sky
27.01.2016

Why would the sky look like a giant fan? Airglow. The featured intermittent green glow appeared to rise from a lake through the arch of our Milky Way Galaxy, as captured last summer next to Bryce Canyon in Utah, USA.

Sea and Sky Glows over the Oregon Coast
28.08.2018

Every step caused the sand to light up blue. That glow was bioluminescence -- a blue radiance that also lights the surf in this surreal scene captured last month at Meyer's Creek Beach in Oregon, USA. Volcanic stacks dot the foreground sea, while a thin fog layer scatters light on the horizon.

The Infrared Sky
28.01.1998

Three major sources contribute to the far-infrared sky: our Solar System, our Galaxy, and our Universe. The above image, in representative colors, is a projection of the entire infrared sky created from years of observations by the robot spacecraft COBE.

An Airglow Fan from Lake to Sky
3.02.2019

Why would the sky look like a giant fan? Airglow. The featured intermittent green glow appeared to rise from a lake through the arch of our Milky Way Galaxy, as captured during 2015 next to Bryce Canyon in Utah, USA.