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Astronomers using the Hubble Space Telescope have captured the most comprehensive picture ever assembled of the evolving universe—and one of the most colorful. The study is called the Ultraviolet Coverage of the Hubble Ultra Deep Field project. Prior to this survey, astronomers were in a curious position. They knew a lot about star formation occurring in nearby galaxies thanks to UV telescope facilities such as NASA's Galex observatory, which operated from 2003 to 2013. And, thanks to Hubble's near-infrared and visible capability, they had also studied star birth in the most distant galaxies. We see these distant galaxies in their...

Explanation: The space station has caught a dragon. Specifically, in mid-April, the International Space Station captured the unmanned SpaceX Dragon capsule sent to resupply the orbiting outpost. Pictured above, the station's Canadarm2 had just grabbed the commercial spaceship. The Dragon capsule was filled with over 5000 lbs (2260 kilos) of supplies and experiments to be used by the current band of six ISS astronauts that compose Expedition 39, as well as the six astronauts that compose Expedition 40. After docking with the ISS, the Dragon capsule was unloaded and eventually released, splashing down in the Pacific Ocean on May 18....

NASA has been talking about sending people to Mars by 2035. That goal is still on the books, despite recent upheaval in the space program, according to two of the agency's top scientists. "In the near term, Mars remains our primary focus," Ellen Stofan, NASA's chief scientist said May 15 in a talk at the Royal Institution in London ... ....scientists [also] decided to "redirect" an asteroid into an orbit of the moon and are searching for an asteroid that's an appropriate candidate. "Once we find the right one, we'll use all the technology we've got," he said. "We'll snag...

Explanation: The Cat's Eye Nebula (NGC 6543) is one of the best known planetary nebulae in the sky. Its haunting symmetries are seen in the very central region of this stunning false-color picture, processed to reveal the enormous but extremely faint halo of gaseous material, over three light-years across, which surrounds the brighter, familiar planetary nebula. Made with data from the Nordic Optical Telescope in the Canary Islands, the composite picture shows extended emission from the nebula. Planetary nebulae have long been appreciated as a final phase in the life of a sun-like star. Only much more recently however, have...

Explanation: This clear night skyscape captures the colorful glow of aurora australis, the southern lights, just outside the port city of Hobart, Tasmania, Australia, planet Earth. As if staring into the dreamlike scene, the Tasmanian Earth Resources Satellite Station poses in the center, illuminated by nearby city lights. Used to receive data from spacebased Earth observing instruments, including NASA's MODIS and SeaWiFS, the station was decommissioned in 2011 and dismantled only recently, shortly after the picture was taken on April 30. Still shining in southern skies though, the central bulge of our Milky Way galaxy and two bright satellite galaxies...

Explanation: The gorgeous, gaseous shroud of a dying sunlike star, planetary nebula Abell 36 lies a mere 800 light-years away in the constellation of Virgo. At that distance it spans over 1.5 light-years in this sharp telescopic view. Shrugging off its outer layers, the nebula's central star is contracting and becoming hotter, evolving towards a final white dwarf phase. In fact, in Abell 36, the central star is estimated to have a surface temperature of over 73,000 K, compared to the Sun's present 6,000 K temperature. As a result, the intensely hot star is much brighter in ultraviolet light, compared...

Explanation: Globular star cluster Omega Centauri, also known as NGC 5139, is some 15,000 light-years away. The cluster is packed with about 10 million stars much older than the Sun within a volume about 150 light-years in diameter, the largest and brightest of 200 or so known globular clusters that roam the halo of our Milky Way galaxy. Though most star clusters consist of stars with the same age and composition, the enigmatic Omega Cen exhibits the presence of different stellar populations with a spread of ages and chemical abundances. In fact, Omega Cen may be the remnant core of...

Explanation: Stars are forming in the gigantic dust pillar called the Cone Nebula. Cones, pillars, and majestic flowing shapes abound in stellar nurseries where natal clouds of gas and dust are buffeted by energetic winds from newborn stars. The Cone Nebula, a well-known example, lies within the bright galactic star-forming region NGC 2264. The Cone was captured in unprecedented detail in this close-up composite of several observations from the Earth-orbiting Hubble Space Telescope. While the Cone Nebula, about 2,500 light-years away in Monoceros, is around 7 light-years long, the region pictured here surrounding the cone's blunted head is a mere...

Explanation: What's happening at the center of this nebula? Sculpted by stellar winds and radiation, the star factory known as Messier 17 lies some 5,500 light-years away in the nebula-rich constellation Sagittarius. At that distance, this degree wide field of view spans almost 100 light-years. The sharp, composite, color image utilizing data from space and ground based telescopes, follows faint details of the region's gas and dust clouds against a backdrop of central Milky Way stars. Stellar winds and energetic light from hot, massive stars formed from M17's stock of cosmic gas and dust have slowly carved away at the...

Explanation: It is the most expensive and complex ground-based astronomy project ever -- what will it see tonight? The Atacama Large Millimeter Array (ALMA) project consists of 66 dishes, many the size of a small house, situated in the high altitude Atacama Desert in Northern Chile. Together, ALMA observes the skies in high-frequency radio light, a band usually used only for local communication due to considerable absorption by humid air. The thin atmosphere and low humidity above ALMA, however, enable it to see deep into our universe in new and unique ways that allow, for example, explorations of the early...

Explanation: From a camp on the northern shores of the Great Lake Erie, three short bright meteor streaks were captured in this composited night skyscape. Recorded over the early morning hours of May 24, the meteors are elusive Camelopardalids. Their trails point back to the meteor shower's radiant near Polaris, in the large but faint constellation Camelopardalis the camel leopard, or in modern terms the Giraffe. While a few meteors did appear, the shower was not an active one as the Earth crossed through the predicted debris trail of periodic comet 209P/LINEAR. Of course, the long bright streak in the...

Explanation: Why would clouds appear to be different colors? The reason here is that ice crystals in distant cirrus clouds are acting like little floating prisms. Sometimes known as a fire rainbow for its flame-like appearance, a circumhorizon arc lies parallel to the horizon. For a circumhorizontal arc to be visible, the Sun must be at least 58 degrees high in a sky where cirrus clouds are present. Furthermore, the numerous, flat, hexagonal ice-crystals that compose the cirrus cloud must be aligned horizontally to properly refract sunlight in a collectively similar manner. Therefore, circumhorizontal arcs are quite unusual to see....

Explanation: The Rosetta spacecraft captured this remarkable series of 9 frames between March 27 and May 4, as it closed from 5 million to 2 million kilometers of its target comet. Cruising along a 6.5 year orbit toward closest approach to the Sun next year, periodic comet 67P/Churyumov-Gerasimenko is seen moving past a distant background of stars in Ophiuchus and globular star cluster M107. The comet's developing coma is actually visible by the end of the sequence, extending for some 1300 km into space. Rosetta is scheduled for an early August rendezvous with the comet's nucleus. Now clearly active, the...

Explanation: Beautiful emission nebula NGC 6164 was created by a rare, hot, luminous O-type star, some 40 times as massive as the Sun. Seen at the center of the cosmic cloud, the star is a mere 3 to 4 million years old. In another three to four million years the massive star will end its life in a supernova explosion. Spanning around 4 light-years, the nebula itself has a bipolar symmetry. That makes it similar in appearance to more common and familiar planetary nebulae - the gaseous shrouds surrounding dying sun-like stars. Also like many planetary nebulae, NGC 6164 has...

Explanation: How do supercell storm clouds form? Pictured above is a time-lapse video taken last Sunday detailing the formation of one such violent supercell in eastern Wyoming, USA. Starting as part of a large and dark thunderstorm complex, the supercell comes together along with a large rotating updraft of air known as a mesocyclone. Mesocyclones form during rapid changes in wind speed and direction with height and can produce torrential rain, damaging hail, swirling winds, and sometimes tornadoes. Storm watchers are seen studying, imaging, and ultimately running from the developing storm cloud during the video. During the middle part of...

Explanation: M61 is a barred spiral galaxy located in the nearby Virgo Cluster of Galaxies. Visible in M61 are a host of features common to spiral galaxies: bright spiral arms, a central bar, dust lanes, and bright knots of stars. M61, also known as NGC 4303, in similar to our own Milky Way Galaxy. M61 was discovered by telescope in 1779 twice on the same day, but one observer initially mistook the galaxy for a comet. Light from M61 takes about 55 million years to reach us. The above image of the central regions of M61 was taken with the...

Explanation: Sometimes land and sky are both busy and beautiful. The landscape pictured in the foreground encompasses Bryce Canyon in Utah, USA, famous for its many interesting rock structures eroded over millions of years. The skyscape above, photogenic in its own right, encompasses the arching central disk of our Milky Way Galaxy, streaks that include three passing airplanes and at least four Eta Aquariid meteors, and bright stars that include the Summer Triangle. The above image is a digital panorama created from 12 smaller images earlier this month on the night May 6. If you missed the recent Eta Aquariids...

Explanation: What will become of Jupiter's Great Red Spot? Recorded as shrinking since the 1930s, the rate of the Great Red Spot's size appears to have accelerated just in the past few years. A hurricane larger than Earth, the Great Red Spot has been raging at least as long as telescopes could see it. Like most astronomical phenomena, the Great Red Spot was neither predicted nor immediately understood after its discovery. Although small eddies that feed into the storm system seem to play a role, a more full understanding of the gigantic storm cloud remains a topic of continued research,...

Explanation: Gas giant Jupiter is the solar system's largest world with about 320 times the mass of planet Earth. It's also known for a giant swirling storm system, the Great Red Spot, featured in this sharp Hubble image from April 21. Nestled between Jupiter-girdling cloud bands, the Great Red Spot itself could still easily swallow Earth, but lately it has been shrinking. The most recent Hubble observations measure the spot to be about 10,250 miles (16,500 kilometers) across. That's the smallest ever measured by Hubble and particularly dramatic when compared to 14,500 miles measured by the Voyager 1 and 2...

Explanation: Staring up into the martian sky, the Opportunity rover captured an image at 11:02 AM local mean time nearly every 3rd sol, or martian day, for 1 martian year. Of course, the result is this martian analemma, a curve tracing the Sun's motion through the sky in the course of a year (668 sols) on the Red Planet. Spanning Earth dates from July, 16, 2006 to June 2, 2008 the images are shown composited in this zenith-centered, fisheye projection. North is at the top surrounded by a panoramic sky and landscape made in late 2007 from inside Victoria crater....