The International Space Station over...

2016-04-18

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 ...

Asperatus Clouds Over New Zealand

2016-04-17 Witta Priester

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, ...

Heliopause Electrostatic Rapid...

2016-04-16

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 ...

Mercury and Crescent Moon Set

2016-04-15 Miguel Claro

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 ...

Full Venus and Crescent Moon Rise

2016-04-14 El Cielo de Canarias

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 ...

Orion in Red and Blue

2016-04-13 David Lindemann

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 ...

Combined Solar Eclipse Corona from...

2016-04-12

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 -- ...

The Comet and the Star Cluster

2016-04-11 José J. Chambó

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 ...

Cassini Approaches Saturn

2016-04-10

Cassini, a robot spacecraft launched in 1997 by NASA, became close enough in 2002 to resolve many rings and moons of its destination planet: Saturn. At that time, Cassini snapped several images during an engineering test. Several of those ...

A Green Flash of Spring

2016-04-09 Murray Schukar

Taken on March 20 from the top of Haleakala on the isle of Maui, planet Earth, the first sunrise of northern spring is pictured in this vacation snapshot. The telephoto view from the volcanic caldera above a sea of clouds also captures an elusive ...