The cliffs and boulder-strewn surface of Comet 67P/Churyumov-Gerasimenko, as imaged by the European Space Agency’s Rosetta spacecraft from 38 miles off the surface last Friday. Although the comet’s nucleus appears bright in this view against the blackness of space, its surface albedo is so low that it’s more comparable in brightness to a charcoal briquette (image credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA).
True-color image of Mars taken during a February, 2007 pass by the European Space Agency’s Rosetta spacecraft. Rosetta was about 150,000 miles from the red planet at the time (image credit: ESA/OSIRIS).
Twenty five years ago, this was Voyager 2’s three million mile view of the receding ice giant Neptune and its largest moon Triton, three days after the spacecraft completed the first (and only) flyby of the most distant planet in our solar system (image credit: NASA).
Dust and scattered boulders accumulate in the “neck” connecting the two lobes of Comet 67P/Churyumov-Gerasimenko, as seen by ESA’s Rosetta spacecraft from orbit around the comet’s nucleus on August 7th. Rosetta caught up with the comet this month after a ten year journey, and will accompany it on its plummet toward our Sun in the months ahead. The European Space Agency’s earthbound team is currently surveying the object to locate the ideal landing spot for its onboard Philae lander, set to deploy in November (image credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA).
Our sun’s closest neighbors: NASA’s Wide-field Infrared Survey Explorer, or WISE, discovered two of the four nearest—the binary brown dwarf system WISE 1049-5319, and the brown dwarf WISE J085510.83-071442.5.
The closest system to the sun is a trio of stars 4.37 light years away that consists of a binary, Alpha Centauri AB, and a distant companion, Proxima Centauri (image credit: Penn State University).
Our most recently discovered neighbor is also the coldest known brown dwarf. This illustration depicts the dim, frigid WISE J085510.83-071442.5, found by NASA’s Wide-field Infrared Survey Explorer and confirmed by the Spitzer Space Telescope. Without enough mass to trigger fusion and too dim to be seen by the naked eye, nearby brown dwarfs show up in infra-red as objects moving quickly against the cosmic backdrop. WISE J085510.83-071442.5 is as cold as our planet’s North Pole, and is a relatively close 7.2 light years away from our Sun (image credit: Penn State University/NASA/JPL-Caltech).
Narrow-angle, approximate color mosaic of Mercury’s crescent, south-to-north, assembled from twenty images taken by the Messenger spacecraft as it flew by the innermost planet in October of 2008 (image credit: NASA/JHUAPL/Gordan Ugarkovic).
Artist’s concept of Kepler-186f, the first Earth-sized alien world yet discovered in its system’s “habitable zone,” where liquid water could conceivably exist on the surface. Kepler-186f is less than ten percent larger than our planet. Though a year on this world is only 130 days long and it orbits its star at around the distance that Mercury orbits our sun, Kepler 186 is a smaller, cooler red dwarf. Four other planets have been discovered orbiting even closer to Kepler 186 in this alien planetary system around 500 light years away from us (image credit: NASA Ames/SETI Institute/JPL-Caltech).
In Green Company: Aurora, mountain climber, and sunset over Svolvær, Norway (image credit: Max Rive).
This morning, the Moon transited the Sun from the vantage point of NASA’s orbiting Solar Dynamics Observatory for two hours of observation in various wavelengths (this image was taken at 171 angstroms—extreme ultraviolet). Just as the Moon left SDO’s field of view, an M8-class solar flare erupted from sunspot group AR 11967 (image credit: NASA/SDO).
Saturn’s churning north polar vortex, imaged in the infrared by the Cassini spacecraft from 476,000 miles away on June 14, 2013 (image credit: NASA/JPL-Caltech/SSI).
Good morning! An unusual perspective on Earth’s aurora - the Southern Lights, full circle over Antarctica.
The icy moon Mimas, seen passing in front of Saturn by NASA’s Cassini spacecraft from a distance of 870,000 miles on January 18, 2005. From this angle of view, the blue clouds of Saturn’s northern hemisphere were striated by shadows cast by the giant planet’s intricate ring system (image credit: NASA/JPL/SSI).
Southern hemisphere of Jupiter, a spherical projection of high-detail images taken by NASA’s Cassini spacecraft as it flew past the gas giant in December of 2000 on its way to Saturn. Thick haze and the angle of view prevented Cassini from clearly imaging the planet’s south pole (image credit: NASA/JPL/SSI).