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Explanation: What's that rising from the clouds? The space shuttle. Sometimes, if you looked out the window of an airplane at just the right place and time, you could have seen something very unusual -- a space shuttle launching to orbit. Images of the rising shuttle and its plume became widely circulated over the web shortly after Endeavour's final launch in 2011 May. The above image was taken from a shuttle training aircraft by NASA and is not copyrighted. Taken well above the clouds, the image can be matched with similar images of the same shuttle plume taken below the...

Explanation: Hot, young stars and cosmic pillars of gas and dust seem to crowd into NGC 7822. At the edge of a giant molecular cloud toward the northern constellation Cepheus, the glowing star forming region lies about 3,000 light-years away. Within the nebula, bright edges and dark shapes are highlighted in this colorful skyscape. The image includes data from narrowband filters, mapping emission from atomic oxygen, hydrogen, and sulfur into blue, green, and red hues. The atomic emission is powered by energetic radiation from the hot stars, whose powerful winds and radiation also sculpt and erode the denser pillar shapes....

you can see the best-ever images of Pluto, our solar system's most distant (dwarf) planet. The animation is made up of images taken by NASA's New Horizons spacecraft between April 12 and 18 from a distance of 69 to 64 million miles from Pluto. They capture one complete rotation of Pluto and its moon Charon... The images have already surpassed the Hubble's resolution, but there are plenty of features too subtle for the spacecraft to pick up. In fact, the images don't even show all of Pluto's known moons yet -- let alone any smaller ones we've yet to discover...

Explanation: In the dusty sky toward the constellation Taurus and the Orion Arm of our Milky Way Galaxy, this broad mosaic follows dark and faint reflection nebulae along the region's fertile molecular cloud. The six degree wide field of view starts with long dark nebula LDN 1495 stretching from the lower left, and extends beyond the (upside down) bird-like visage of the Baby Eagle Nebula, LBN 777, at lower right. Small bluish reflection nebulae surround scattered fainter Taurus stars, sights often skipped over in favor of the constellation's better known, brighter celestial spectacles. Associated with the young, variable star RY...

Explanation: NGC 6240 offers a rare, nearby glimpse of a cosmic catastrophe in its final throes. The titanic galaxy-galaxy collision takes place a mere 400 million light-years away in the constellation Ophiuchus. The merging galaxies spew distorted tidal tails of stars, gas, and dust and undergo fast and furious bursts of star formation. The two supermassive black holes in the original galactic cores will also coalesce into a single, even more massive black hole and soon, only one large galaxy will remain. This dramatic image of the scene is a composite of narrowband and near-infrared to visible broadband data from...

One of the great physics experiments of our age looks ready to begin its quest.Scientists have held a dedication ceremony to inaugurate the Advanced Ligo facilities in the US. This pair of widely separated laboratories will be hunting for gravitational waves. These ripples in the fabric of space-time are predicted to result from extreme cosmic events, such as the merger of black holes and the explosive demise of giant stars. Confirmation of the waves' existence should open up a new paradigm in astronomy. It is one that would no longer depend on traditional light telescopes to observe and understand phenomena...

Explanation: What that looming behind this gravel-strewn hill on Comet Churyumov–Gerasimenko? A jagged cliff. The unusual double-lobed nucleus of Comet 67P/Churyumov–Gerasimenko lends itself to unusual and dramatic vistas, another of which has been captured by the Rosetta spacecraft that arrived at the comet last September. The featured cometscape, taken last October and digitally enhanced, spans about 850 meters across. Meanwhile, Comet Churyumov–Gerasimenko continues to sprout jets as it nears its closest approach to the Sun in August. Along the way, Rosetta will continue listening for signals from Philae, a probe that landed on the nucleus but rebounded to an unknown...

Scientists from Rosetta’s OSIRIS team have discovered an extraordinary formation on the larger lobe of comet 67P/Churyumov-Gerasimenko in the Aker region. From a group of three boulders the largest one with a diameter of approximately 30 meters stands out: images obtained on 16 September 2014 from a distance of 29 kilometers with the help of Rosetta’s scientific imaging system OSIRIS show it to perch on the rim of a small depression. There seems to be only a very small contact area with the nucleus. Similar geological formations are found also on Earth. So-called balancing rocks touch the underground with only...

Explanation: Globular star cluster 47 Tucanae is a jewel box of the southern sky. Also known as NGC 104, it roams the halo of our Milky Way Galaxy along with over 150 other globular star clusters. The second brightest globular cluster (after Omega Centauri) as seen from planet Earth, 47 Tuc lies about 17,000 light-years away and can be spotted naked-eye near the Small Magellanic Cloud in the constellation of the Toucan. The dense cluster is made up of hundreds of thousands of stars in a volume only about 120 light-years across. Recent observations have shown that 47 Tuc's white...

Explanation: It was one of the quietest nights of aurora in weeks. Even so, in northern- Iceland during last November, faint auroras lit up the sky every clear night. The featured 360-degree panorama is the digital fusion of four wide-angle cameras each simultaneously taking 101 shots over 42 minutes. In the foreground is serene Lake Myvatn dotted with picturesque rock formations left over from ancient lava flows. Low green auroras sweep across the sky above showing impressive complexity near the horizon. Stars far in the distance appear to show unusual trails -- as the Earth turned -- because early exposures...

Explanation: Like a pearl, a white dwarf star shines best after being freed from its shell. In this analogy, however, the Sun would be a mollusk and its discarded hull would shine prettiest of all! In the above shell of gas and dust, the planetary nebula designated NGC 2440, contains one of the hottest white dwarf stars known. The glowing stellar pearl can be seen as the bright dot near the image center. The portion of NGC 2440 shown spans about one light year. The center of our Sun will eventually become a white dwarf, but not for another five...

Explanation: This close-up from the Mars Reconnaissance Orbiter's HiRISE camera shows weathered craters and windblown deposits in southern Acidalia Planitia. A striking shade of blue in standard HiRISE image colors, to the human eye the area would probably look grey or a little reddish. But human eyes have not gazed across this terrain, unless you count the eyes of NASA astronauts in the scifi novel The Martian by Andy Weir. The novel chronicles the adventures of Mark Watney, an astronaut stranded at the fictional Mars mission Ares 3 landing site corresponding to the coordinates of this cropped HiRISE frame. For...

The merger of the Milky Way and Andromeda galaxy won’t happen for another 4 billion years, but the recent discovery of a massive halo of hot gas around Andromeda may mean our galaxies are already touching. Andromeda’s halo is gargantuan. Extending for at least 2 million light years, if we could see in our night sky it would be 100 times the diameter of the Moon or 50 degrees across! [the entire sky, from horizon to horizon, is approx 180 deg -ETL] Credit: NASA University of Notre Dame astrophysicist Nicholas Lehner led a team of scientists using the Hubble Space...

Explanation: In this sharp snapshot, the Solar System's largest moon Ganymede poses next to Jupiter, the largest planet. Captured on March 10 with a small telescope from our fair planet Earth, the scene also includes Jupiter's Great Red Spot, the Solar System's largest storm. In fact, Ganymede is about 5,260 kilometers in diameter. That beats out all three of its other fellow Galilean satellites, along with Saturn's Moon Titan at 5,150 kilometers and Earth's own Moon at 3,480 kilometers. Though its been shrinking lately, the Great Red Spot's diameter is still around 16,500 kilometers. Jupiter, the Solar System's ruling gas...

Explanation: Now at Ceres, Dawn's camera recorded this closer view of the dwarf planet's northern hemisphere and one of its mysterious bright spots on May 4. A sunlit portrait of a small, dark world about 950 kilometers in diameter, the image is part of a planned sequence taken from the solar-powered spacecraft's 15-day long RC3 mapping orbit at a distance of 13,600 kilometers (8,400 miles). The animated sequence shows Ceres' rotation, its north pole at the top of the frame. Imaged by Hubble in 2004 and then by Dawn as it approached Ceres in 2015, the bright spot itself is...

Explanation: Sculpted by stellar winds and radiation, a magnificent interstellar dust cloud by chance has assumed this recognizable shape. Fittingly named the Horsehead Nebula, it is some 1,500 light-years distant, embedded in the vast Orion cloud complex. About five light-years "tall", the dark cloud is cataloged as Barnard 33 and is visible only because its obscuring dust is silhouetted against the glowing red emission nebula IC 434. Stars are forming within the dark cloud. Contrasting blue reflection nebula NGC 2023, surrounding a hot, young star, is at the lower left. The gorgeous featured image combines both narrowband and broadband images....

It is an obvious truth we too often forget. At the Albert Einstein Memorial, on the grounds of the National Academy of Sciences in Washington, D.C., an explanatory sign states a simple fact that refutes the argument President Barack Obama's science adviser once made for redistributing wealth and limiting human population so as to save the human race from a poverty he claimed must inevitably intensify as our numbers increase. "At Einstein's feet lies a circular sky map representing the planets, sun, moon, and stars, positioned as observed by astronomers from the U.S. Naval Observatory at noon on the day...

Astronomers have been arguing over just how many spiral arms our galaxy exhibits. Is the Milky Way a four or two-armed spiral galaxy? Astronomers had often assumed the Milky Way was potentially a four-armed spiral galaxy, but comparatively recent observations from NASA's Spitzer telescope implied the galaxy had two spiral arms. In 2013, astronomers mapped star forming regions and argued they had found the two missing arms, bringing the total number of arms back to four. The case for a four-armed Milky Way may have just gotten stronger. A team of Brazilian astronomers used star clusters embedded in their natal...

A COLOSSAL asteroid hurtling through space is feared to be one of the biggest EVER to threaten a collision with Earth. The gigantic missile thought to measure almost a mile across will brush closer than previous monsters which have sparked a global panic. Worried astronomers warned 1999 FN53, which is an eighth of the size of Mount Everest, will skim the Earth in TWO DAYS. A collision would be nothing short of catastrophic triggering mass destruction, earthquakes and global extinction. The monster is more than TEN TIMES bigger than other meteorites currently visible on NASA’s Near Earth Object radar. It...

Explanation: How different does sunset appear from Mars than from Earth? For comparison, two images of our common star were taken at sunset, one from Earth and one from Mars. These images were scaled to have same angular width and featured here side-by-side. A quick inspection will reveal that the Sun appears slightly smaller from Mars than from Earth. This makes sense since Mars is 50% further from the Sun than Earth. More striking, perhaps, is that the Martian sunset is noticeably bluer near the Sun than the typically orange colors near the setting Sun from Earth. The reason for...