Like Earth's moon, Saturn's largest moon Titan is locked in synchronous rotation. This mosiac of images recorded by the Cassini spacecraft in May of 2012 show's its anti-Saturn side, the side always facing away from the ringed gas giant. The only moon in the solar system with a dense atmosphere, Titan is the only solar system world besides Earth known to have standing bodies of liquid on its surface and an earthlike cycle of liquid rain and evaporation. Its high altitude layer of atmospheric haze is evident in the Cassini view of the 5,000 kilometer diameter moon over Saturn's rings and cloud tops. Near center is the dark dune-filled region known as Shangri-La. The Cassini-delivered Huygens probe rests below and left of center, after the most distant landing for a spacecraft from Earth.

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View of bus station and metro bridge from Slussen towards Gamla stan (Old town) and Riddarholmen. In the background Kungsholmen and Stockholm City Hall

larger blue-white galaxy in a field of background orange galaxies

At first glance, this image is dominated by the vibrant glow of the swirling spiral to the lower left of the frame. However, this galaxy is far from the most interesting spectacle here — behind it sits a galaxy cluster.

Galaxies are not randomly distributed in space; they swarm together, gathered up by the unyielding hand of gravity, to form groups and clusters. The Milky Way is a member of the Local Group, which is part of the Virgo Cluster, which in turn is part of the 100,000-galaxy-strong Laniakea Supercluster.

The galaxy cluster seen in this image is known as SDSS J0333+0651. Clusters such as this can help astronomers understand the distant — and therefore early — universe. SDSS J0333+0651 was imaged as part of a study of star formation in far-flung galaxies. Star-forming regions are typically not very large, stretching out for a few hundred light-years at most, so it is difficult for telescopes to resolve them at a distance. Even using its most sensitive and highest-resolution cameras, Hubble can’t resolve very distant star-forming regions, so astronomers use a cosmic trick: they search instead for galaxy clusters, which have a gravitational influence so immense that they warp the space-time around them. This distortion acts like a lens, magnifying the light of galaxies (and their star-forming regions) sitting far behind the cluster and producing elongated arcs like the one seen in the upper left part of this image.

Credit: ESA/Hubble & NASA


This stunning group of galaxies is far, far away, about 450 million light-years from planet Earth and cataloged as galaxy cluster Abell S0740. Dominated by the cluster's large central elliptical galaxy (ESO 325-G004), this reprocessed Hubble Space Telescope view takes in a remarkable assortment of galaxy shapes and sizes with only a few spiky foreground stars scattered through the field. The giant elliptical galaxy (right of center) spans over 100,000 light years and contains about 100 billion stars, comparable in size to our own spiral Milky Way galaxy. The Hubble data can reveal a wealth of detail in even these distant galaxies, including arms and dust lanes, star clusters, ring structures, and gravitational lensing arcs.

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Female leopard (Panthera pardus) descending from its favourite tree, where it spent the warmest hours of the day. Londolozi, Sabi Sand, South Africa

A close-up image of a 2-inch-deep hole produced using a new drilling technique for NASA's Curiosity rover

This close-up image is of a 2-inch-deep hole produced using a new drilling technique for NASA's Curiosity rover. The hole is about 0.6 inches (1.6 centimeters) in diameter. This image was taken by Curiosity's Mast Camera (Mastcam) on Sol 2057. It has been white balanced and contrast-enhanced.

Curiosity drilled this hole in a target called "Duluth" on May 20, 2018. It was the first rock sample captured by the drill since October 2016. A mechanical issue took the drill offline in December 2016.

Engineers at NASA's Jet Propulsion Laboratory had to innovate a new way for the rover to drill in order to restore this ability. The new technique, called Feed Extended Drilling (FED) keeps the drill's bit extended out past two stabilizer posts that were originally used to steady the drill against Martian rocks. It lets Curiosity drill using the force of its robotic arm, a little more like a human would while drilling into a wall at home.

Image Credit: NASA


Named for a cosmic cloud hunter, Australian astronomer Colin Stanley Gum (1924-1960), The Gum Nebula is so large and close it is actually hard to see. In fact, we are only about 450 light-years from the front edge and 1,500 light-years from the back edge of this interstellar expanse of glowing hydrogen gas. Covered in this 40+ degree-wide monochrome mosaic of Hydrogen-alpha images, the faint emission region stands out against the background of Milky Way stars. The complex nebula is thought to be a supernova remnant over a million years old, sprawling across the Ship's southern constellations Vela and Puppis. This spectacular wide field view also explores many objects embedded in The Gum Nebula, including the younger Vela supernova remnant.

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Exemplar of red rock crab (Grapsus grapsus), Cerro Brujo, San Cristobal Island, Galapagos Islands, Ecuador.

GRACE Follow-On spacecraft launch onboard a SpaceX Falcon 9 rocket, Tuesday, May 22, 2018

The GRACE-FO, or Gravity Recovery and Climate Experiment Follow-On, mission lifted off on Tuesday, May 22, 2018, from Space Launch Complex 4E at Vandenberg Air Force Base in California. GRACE-FO is a joint project of NASA and the German Research Centre for Geosciences. The mission will measure changes in how mass is redistributed within and among Earth's atmosphere, oceans, land and ice sheets, as well as within Earth itself. GRACE-FO is sharing its ride to orbit with five Iridium NEXT communications satellites as part of a commercial rideshare agreement.

This image, and others, are available on Flickr:

Image Credit: NASA/Bill Ingalls

GRACE-FO launch

The NASA/German Research Centre for Geosciences Gravity Recovery and Climate Experiment Follow-on (GRACE-FO) mission launched onboard a SpaceX Falcon 9 rocket, Tuesday, May 22, 2018, from Space Launch Complex 4E at Vandenberg Air Force Base in California. The mission will measure changes in how mass is redistributed within and among Earth's atmosphere, oceans, land and ice sheets, as well as within Earth itself. GRACE-FO is sharing its ride to orbit with five Iridium NEXT communications satellites as part of a commercial rideshare agreement.
This image, and others, are also available Flickr:

Image Credit: NASA/Bill Ingalls


This galaxy is having a bad millennium. In fact, the past 100 million years haven't been so good, and probably the next billion or so will be quite tumultuous. Visible toward the lower right, NGC 4038 used to be a normal spiral galaxy, minding its own business, until NGC 4039, to its upper left, crashed into it. The evolving wreckage, known famously as the Antennae, is featured here. As gravity restructures each galaxy, clouds of gas slam into each other, bright blue knots of stars form, massive stars form and explode, and brown filaments of dust are strewn about. Eventually the two galaxies will converge into one larger spiral galaxy. Such collisions are not unusual, and even our own Milky Way Galaxy has undergone several in the past and is predicted to collide with our neighboring Andromeda Galaxy in a few billion years. The frames that compose this image were taken by the orbiting Hubble Space Telescope by professional astronomers to better understand galaxy collisions. These frames -- and many other deep space images from Hubble -- have since been made public, allowing interested amateurs to download and process them into, for example, this visually stunning composite.

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The Red Arrows roll upside down in tight formation during display training over their headquarters at RAF Scampton in Lincolnshire

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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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

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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)


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.