Why does the right part of this image of the Moon stand out? Shadows. The terminator line -- the line between light and dark -- occurs in the featured image so that just over half the Moon's face is illuminated by sunlight. The lunar surface appears different nearer the terminator because there the Sun is nearer the horizon and therefore causes shadows to become increasingly long. These shadows make it easier for us to discern structure, giving us depth cues so that the two-dimensional image, when dominated by shadows, appears almost three-dimensional. Therefore, as the Moon fades from light to dark, shadows not only tell us the high from the low, but become noticeable for increasingly shorter structures. For example, many craters appear near the terminator because their height makes them easier to discern there. The image was taken two weeks ago when the lunar phase was waning gibbous. The next full moon, a Moon without shadows, will occur one week from today.

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European robin (Erithacus rubecula) juvenile.jpg

This is a good time of year to spot a juvenile European robin (Erithacus rubecula). You can just see the beginnings of the orange breast.


Orbital ATK Antares rocket streaks toward orbit after liftoff

The Orbital ATK Antares rocket, with the Cygnus spacecraft onboard, launches from Pad-0A, Monday, May 21, 2018 at NASA's Wallops Flight Facility in Virginia. Orbital ATK’s ninth contracted cargo resupply mission with NASA to the International Space Station will deliver approximately 7,400 pounds of science and research, crew supplies and vehicle hardware to the orbital laboratory and its crew.

Photo Credit: NASA/Aubrey Gemignani


Source: www.nasa.gov
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Borgmühle (built 1406) in Lüdinghausen, North Rhine-Westphalia, Germany


Orbital ATK Antares vertical at launchpad

The Orbital ATK Antares rocket, with the Cygnus spacecraft onboard, is seen at launch Pad-0A, Saturday, May 19, 2018, at Wallops Flight Facility in Virginia. Liftoff is currently targeted for 4:39 a.m. Eastern on Monday, May 21.

The Antares will launch with the Cygnus spacecraft filled with 7,400 pounds of cargo for the International Space Station, including science experiments, crew supplies, and vehicle hardware. The mission is Orbital ATK's ninth contracted cargo delivery flight to the space station for NASA.

More about the cargo aboard Cygnus: Science Launching to the Space Station Looks Forward and Back

Photo Credit: (NASA/Aubrey Gemignani)


Source: www.nasa.gov

In the heart of monstrous Tarantula Nebula lies huge bubbles of energetic gas, long filaments of dark dust, and unusually massive stars. In the center of this heart, is a knot of stars so dense that it was once thought to be a single star. This star cluster, labeled as R136 or NGC 2070, is visible just above the center of the featured image and home to a great number of hot young stars. The energetic light from these stars continually ionizes nebula gas, while their energetic particle wind blows bubbles and defines intricate filaments. The representative-color picture, a digital synthesis of images from the NASA/ESA orbiting Hubble Space Telescope and ESO's ground-based New Technology Telescope, shows great details of the LMC nebula's tumultuous center. The Tarantula Nebula, also known as the 30 Doradus nebula, is one of the largest star-formation regions known, and has been creating unusually strong episodes of star formation every few million years.


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Haus der Kulturen der Welt, Berlin. The building is located in the Tiergarten park. It was formerly known as the Kongresshalle conference hall. It was designed in 1957 by the American architect Hugh Stubbins. The building is reflecting in the water basin in front of it.



Dodging powerful laser beams, a drone captured this stunning aerial view. The confrontation took place above the 8.2 meter diameter Very Large Telescopes of the Paranal Observatory on planet Earth. Firing during a test of the observatory's 4 Laser Guide Star Facility, the lasers are ultimately battling against the blurring effect of atmospheric turbulence by creating artificial guide stars. The guide stars are actually emission from laser excited sodium atoms at high altitudes within the telescopic field of view. Guide star image fluctuations are used in real-time to correct for atmospheric blurring by controlling a deformable mirror in the telescope's optical path. Known as adaptive optics, the technique can produce images at the diffraction limit of the telescope. That's the same sharpness you would get if the telescope were in space.



Posing near the western horizon, a brilliant evening star and slender young crescent shared reflections in a calm sea last Thursday after sunset. Recorded in this snapshot from the Atlantic beach at Santa Marinella near Rome, Italy, the lovely celestial conjunction of the two brightest beacons in the night sky could be enjoyed around the world. Seaside, light reflected by briefly horizontal surfaces of the gentle waves forms the shimmering columns across the water. Similar reflections by fluttering atmospheric ice crystals can create sometimes mysterious pillars of light. Of course, earthlight itself visibly illuminates the faint lunar night side.


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The Fernsehturm (in english "Television Tower") is a television tower located in central Berlin, not far from Alexanderplatz, Germany. The tower was constructed between 1965 and 1969 by the administration of the German Democratic Republic with the intention to became a symbol of Berlin, which it remains today. With its height of 368 metres (1,207 ft) (including antenna) it is the tallest structure in Germany, and the second tallest structure in the European Union just beaten by the Riga Radio and TV Tower, which is 50 centimetres (20 in) higher.


An Orbital ATK rocket rolls out to launch Pad-0A at NASA's Wallops Flight Facility on May 17, 2018, for launch on May 20.

Editor's note: The original launch date of May 20 has changed to May 21.

An Orbital ATK rocket rolls out to launch Pad-0A at NASA's Wallops Flight Facility on May 17, 2018, in advance of a May 21 launch from Wallops Island, VA. The Antares will launch a Cygnus spacecraft on a cargo resupply mission to the International Space Station. The mission is Orbital ATK’s ninth contracted cargo delivery flight to the space station for NASA. Among the 7,400 pounds of cargo onboard Cygnus are science experiments, crew supplies and vehicle hardware. Launch is scheduled for 5:04 a.m. EDT on Sunday, May 20.

Image Credit: NASA/Aubrey Gemignani


Source: www.nasa.gov
Bright white galaxy with a black bar along the centerline

Resembling a wizard’s staff set aglow, NGC 1032 cleaves the quiet darkness of space in two in this image from the NASA/ESA Hubble Space Telescope.

NGC 1032 is located about a hundred million light-years away in the constellation Cetus (the Sea Monster). Although beautiful, this image perhaps does not do justice to the galaxy’s true aesthetic appeal: NGC 1032 is actually a spectacular spiral galaxy, but from Earth, the galaxy’s vast disk of gas, dust and stars is seen nearly edge-on.

A handful of other galaxies can be seen lurking in the background, scattered around the narrow strip of NGC 1032. Many are oriented face-on or at tilted angles, showing off their glamorous spiral arms and bright cores. Such orientations provide a wealth of detail about the arms and their nuclei, but fully understanding a galaxy’s three-dimensional structure also requires an edge-on view. This gives astronomers an overall idea of how stars are distributed throughout the galaxy and allows them to measure the “height” of the disk and the bright star-studded core.


Credit: ESA/Hubble & NASA
Text: European Space Agency


Source: www.nasa.gov
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Pantala flavescens, Globe skimmer, Globe wanderer or Wandering glider, is a wide-ranging dragonfly of the family Libellulidae.


Ricky Arnold

NASA astronaut @astro_ricky Ricky Arnold took this selfie during the May 16, 2018, spacewalk to perform upgrades on the International Space Station, saying in a tweet "An amazing view of our one and only planet. #Spacewalk #EVA50."

Arnold and fellow spacewalker Drew Feustel donned spacesuits and worked for more than six hours outside the station to finish upgrading cooling system hardware and install new and updated communications equipment for future dockings of commercial crew spacecraft. 

Image Credit: NASA


Source: www.nasa.gov

This pretty cosmic cloud lies some 1,500 light-years away, it shape and color reminiscent of a blue robin's egg. It spans about 3 light-years, nested securely within the boundaries of the southern constellation Fornax. Recognized as a planetary nebula, NGC 1360 doesn't represent a beginning though. Instead it corresponds to a brief and final phase in the evolution of an aging star. In fact, visible in the telescopic image the central star of NGC 1360 is known to be a binary star system likely consisting of two evolved white dwarf stars, less massive but much hotter than the Sun. Their intense and otherwise invisible ultraviolet radiation has stripped away electrons from the atoms in the surrounding gaseous shroud. The predominant blue-green hue of NGC 1360 seen here is the strong emission produced as electrons recombine with doubly ionized oxygen atoms.



What lies at the bottom of Hyperion's strange craters? To help find out, the robot Cassini spacecraft that once orbited Saturn swooped past the sponge-textured moon in 2005 and 2010 and took images of unprecedented detail. A six-image mosaic from the 2005 pass, featured here in natural color, shows a remarkable world strewn with strange craters and an odd sponge-like surface. At the bottom of most craters lies some type of unknown dark reddish material. This material appears similar to that covering part of another of Saturn's moons, Iapetus, and might sink into the ice moon as it better absorbs warming sunlight. Hyperion is about 250 kilometers across, rotates chaotically, and has a density so low that it likely houses a vast system of caverns inside.



Four hundred years ago today (May 15, 1618) Johannes Kepler discovered the simple mathematical rule governing the orbits of the solar system's planets, now recognized as Kepler's Third Law of planetary motion. At that time he was living in this tall house on The Hofgasse, a narrow street near the castle and main square of the city of Linz, Austria, planet Earth. The conclusive identification of this residence (Hofgasse 7) as the location of the discovery of his third law is a recent discovery itself. Erich Meyer of the Astronomical Society of Linz was able to solve the historical mystery, based in part on descriptions of Kepler's own observations of lunar eclipses. A key figure in the 17th century scientific revolution, Kepler supported Galileo's discoveries and the Copernican system of planets orbiting the Sun instead of the Earth. He showed that planets move in ellipses around the Sun (Kepler's First Law), that planets move proportionally faster in their orbits when they are nearer the Sun (Kepler's Second Law), and that more distant planets take proportionally longer to orbit the Sun (Kepler's Third Law).



Captured last week after sunset on a Chilean autumn night, an exceptional airglow floods this allsky view from Las Campanas Observatory. The airglow was so intense it diminished parts of the Milky Way as it arced horizon to horizon above the high Atacama desert. Originating at an altitude similar to aurorae, the luminous airglow is due to chemiluminescence, the production of light through chemical excitation. Commonly recorded in color by sensitive digital cameras, the airglow emission here is fiery in appearance. It is predominately from atmospheric oxygen atoms at extremely low densities and has often been present during southern hemisphere nights over the last few years. Like the Milky Way, on that dark night the strong airglow was very visible to the eye, but seen without color. Jupiter is brightest celestial beacon though, standing opposite the Sun and near the central bulge of the Milky Way rising above the eastern (top) horizon. The Large and Small Magellanic clouds both shine through the airglow to the lower left of the galactic plane, toward the southern horizon.


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Chapel of the Holy Sepulchre (or Blood Chapel), Monastery Endowment of the Holy Grave, Heiligengrabe, Brandenburg, Germany


Southern Greenland town of Narsaq

This image of the southern Greenland town of Narsaq was taken during an Operation IceBridge flight on Apr. 26, 2018. Operation IceBridge, NASA’s longest-running airborne mission to monitor polar ice change, concluded this year’s springtime survey of Arctic sea and land ice on May 2. The flights, which began on March 22, covered the western basin of the Arctic Ocean and Greenland’s fastest-changing glaciers.

Browse more images this year's Operation IceBridge campaign.

Image Credit: NASA/Joe MacGregor
 


Source: www.nasa.gov

This image is not blurry. It shows in clear detail that the largest satellite galaxy to our Milky Way, the Large Cloud of Magellan (LMC), rotates. First determined with Hubble, the rotation of the LMC is presented here with fine data from the Sun-orbiting Gaia satellite. Gaia measures the positions of stars so accurately that subsequent measurements can reveal slight proper motions of stars not previously detectable. The featured image shows, effectively, exaggerated star trails for millions of faint LMC stars. Inspection of the image also shows the center of the clockwise rotation: near the top of the LMC's central bar. The LMC, prominent in southern skies, is a small spiral galaxy that has been distorted by encounters with the greater Milky Way Galaxy and the lesser Small Magellanic Cloud (SMC).

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