Can one galaxy hide behind another? Not in the case of SDP.81. Here the foreground galaxy, shown in blue in an image taken by the Hubble Space Telescope, acts like a huge gravitational lens, pulling light from a background galaxy, shown in red ...
How far can you see? The Andromeda Galaxy 2.5 million light years away is the most distant object easily seen by the unaided eye. Other apparent denizens of the night sky, stars, clusters, and nebulae, typically range from a few hundred to a few ...
The International Space Station is the largest object ever constructed by humans in space. The station perimeter extends over roughly the area of a football field, although only a small fraction of this is composed of modules habitable by ...
What kind of clouds are these? Although their cause is presently unknown, such unusual atmospheric structures, as menacing as they might seem, do not appear to be harbingers of meteorological doom. Known informally as Undulatus asperatus clouds, ...
Want to take a fast trip to the edge of the Solar System? Consider a ride on a Heliopause Electrostatic Rapid Transit System (HERTS). The concept is currently being tested and it might take only 10 to 15 years to make the trip of over 100 ...
Innermost planet Mercury and a thin crescent Moon are never found far from the Sun in planet Earth's skies. Taken near dusk on April 8, this colorful evening skyscape shows them both setting toward the western horizon just after the Sun. The ...
Inner planet Venus and a thin crescent Moon are never found far from the Sun in planet Earth's skies. Taken near dawn on April 6, this timelapse composite shows them both rising just before the Sun. The mountaintop Teide Observatory domes on the ...
When did Orion become so flashy? This colorful rendition of part of the constellation of Orion comes from red light emitted by hydrogen and sulfur (SII), and blue-green light emitted by oxygen (OIII). Hues on the featured image were then ...
Sometimes, a total eclipse is a good time to eye the Sun. Taking advantage of an unusual juxtaposition of Earth, Moon and Sun, the featured image depicts the total solar eclipse that occurred last month as it appeared -- nearly simultaneously -- ...
Comet Linear has become unexpectedly bright. The comet, discovered in 2000, underwent a 100-fold outburst just a week before it passed a mere 14 lunar distances from Earth late last month. The comet was captured here last week at about magnitude ...