2015/08/31

Western Wildfire Smoke Has Drifted Over the Atlantic


Smoke from the treacherous western wildfires has wafted across country and out to sea. via NASA http://ift.tt/1MXEkxm

M31: The Andromeda Galaxy


What is the nearest major galaxy to our own Milky Way Galaxy? Andromeda. In fact, our Galaxy is thought to look much like Andromeda. Together these two galaxies dominate the Local Group of galaxies. The diffuse light from Andromeda is caused by the hundreds of billions of stars that compose it. The several distinct stars that surround Andromeda's image are actually stars in our Galaxy that are well in front of the background object. Andromeda is frequently referred to as M31 since it is the 31st object on Messier's list of diffuse sky objects. M31 is so distant it takes about two million years for light to reach us from there. Although visible without aid, the above image of M31 is a digital mosaic of 20 frames taken with a small telescope. Much about M31 remains unknown, including exactly how long it will before it collides with our home galaxy. via NASA http://ift.tt/1Eq99t1

2015/08/30

The Seagull Nebula


A broad expanse of glowing gas and dust presents a bird-like visage to astronomers from planet Earth, suggesting its popular moniker - The Seagull Nebula. This portrait of the cosmic bird covers a 1.6 degree wide swath across the plane of the Milky Way, near the direction of Sirius, alpha star of the constellation Canis Major. Of course, the region includes objects with other catalog designations: notably NGC 2327, a compact, dusty emission region with an embedded massive star that forms the bird's head (aka the Parrot Nebula, above center). Dominated by the reddish glow of atomic hydrogen, the complex of gas and dust clouds with bright young stars spans over 100 light-years at an estimated 3,800 light-year distance. via NASA http://ift.tt/1NZ7MSf

2015/08/29

Puppis A Supernova Remnant


Driven by the explosion of a massive star, supernova remnant Puppis A is blasting into the surrounding interstellar medium about 7,000 light-years away. At that distance, this colorful telescopic field based on broadband and narrowband optical image data is about 60 light-years across. As the supernova remnant expands into its clumpy, non-uniform surroundings, shocked filaments of oxygen atoms glow in green-blue hues. Hydrogen and nitrogen are in red. Light from the initial supernova itself, triggered by the collapse of the massive star's core, would have reached Earth about 3,700 years ago. The Puppis A remnant is actually seen through outlying emission from the closer but more ancient Vela supernova remnant, near the crowded plane of our Milky Way galaxy. Still glowing across the electromagnetic spectrum Puppis A remains one of the brightest sources in the X-ray sky. via NASA http://ift.tt/1LF7ZfT

2015/08/28

Signs of Katrina Linger in the Marshes


Ten years after making landfall, scars from Hurricane Katrina still linger. via NASA http://ift.tt/1MSLi6M

The Large Cloud of Magellan


The 16th century Portuguese navigator Ferdinand Magellan and his crew had plenty of time to study the southern sky during the first circumnavigation of planet Earth. As a result, two fuzzy cloud-like objects easily visible to southern hemisphere skygazers are known as the Clouds of Magellan, now understood to be satellite galaxies of our much larger, spiral Milky Way galaxy. About 160,000 light-years distant in the constellation Dorado, the Large Magellanic Cloud (LMC) is seen here in a remarkably deep, colorful, image. Spanning about 15,000 light-years or so, it is the most massive of the Milky Way's satellite galaxies and is the home of the closest supernova in modern times, SN 1987A. The prominent patch below center is 30 Doradus, also known as the magnificent Tarantula Nebula, is a giant star-forming region about 1,000 light-years across. via NASA http://ift.tt/1KP4xcI

2015/08/27

Astronaut Kjell Lindgren Corrals the Supply of Fresh Fruit


NASA astronaut Kjell Lindgren corrals the supply of fresh fruit that arrived on the Kounotori 5 H-II Transfer Vehicle (HTV-5.) via NASA http://ift.tt/1hI2yjP

Collinder 399: The Coat Hanger


Is this coat hanger a star cluster or an asterism? This cosmic hang-up has been debated over much of last century, as astronomers wondered whether this binocular-visible object is really a physically associated open cluster or a chance projection. Chance star projections are known as asterisms, an example of which is the popular Big Dipper. Recent precise measurements from different vantage points in the Earth's orbit around the Sun have uncovered discrepant angular shifts indicating that the Coat Hanger is better described as an asterism. Known more formally as Collinder 399, this bright stellar grouping is wider than the full moon and lies in the constellation of the Fox (Vulpecula). via NASA http://ift.tt/1EhBBgC

2015/08/26

Stark Beauty of Supersonic Shock Waves


Updating a 150-year-old German photography technique, NASA and the U.S. Air Force released what's called a "schlieren" image of the shock wave from a supersonic aircraft. via NASA http://ift.tt/1fFScyS

Meteors and Milky Way over Mount Ranier


Despite appearances, the sky is not falling. Two weeks ago, however, tiny bits of comet dust were. Featured here is the Perseids meteor shower as captured over Mt. Rainier, Washington, USA. The image was created from a two-hour time lapse video, snaring over 20 meteors, including one that brightened dramatically on the image left. Although each meteor train typically lasts less than a second, the camera was able to capture their color progressions as they disintegrated in the Earth's atmosphere. Here an initial green tint may be indicative of small amounts of glowing magnesium atoms that were knocked off the meteor by atoms in the Earth's atmosphere. To cap things off, the central band of our Milky Way Galaxy was simultaneously photographed rising straight up behind the snow-covered peak of Mt. Rainier. Another good meteor shower is expected in mid-November when debris from a different comet intersects Earth as the Leonids. via NASA http://ift.tt/1Efg08x

2015/08/25

The Lonely Mountain


NASA's Dawn spacecraft spotted this tall, conical mountain on Ceres from a distance of 915 miles (1,470 kilometers). via NASA http://ift.tt/1IcpgoZ

Dione, Rings, Shadows, Saturn


What's happening in this strange juxtaposition of moon and planet? First and foremost, Saturn's moon Dione was captured here in a dramatic panorama by the robotic Cassini spacecraft currently orbiting the giant planet. The bright and cratered moon itself spans about 1100-km, with the large multi-ringed crater Evander visible on the lower right. Since the rings of Saturn are seen here nearly edge-on, they are directly visible only as a thin horizontal line that passes behind Dione. Arcing across the bottom of the image, however, are shadows of Saturn's rings, showing some of the rich texture that could not be seen directly. In the background, few cloud features are visible on Saturn. The featured image was taken during the last planned flyby of Dione by Cassini, as the spacecraft is scheduled to dive into Saturn's atmosphere during 2017. via NASA http://ift.tt/1Jf3ODS

2015/08/24

Sea Ice in the Greenland Sea


As the northern hemisphere experiences the heat of summer, ice moves and melts in the Arctic waters and the far northern lands surrounding it. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Aqua satellite captured this true-color image of sea ice off Greenland on July 16, 2015. via NASA http://ift.tt/1PuQrkn

Giant Cluster Bends Breaks Images


What are those strange blue objects? Many of the brightest blue images are of a single, unusual, beaded, blue, ring-like galaxy which just happens to line-up behind a giant cluster of galaxies. Cluster galaxies here typically appear yellow and -- together with the cluster's dark matter -- act as a gravitational lens. A gravitational lens can create several images of background galaxies, analogous to the many points of light one would see while looking through a wine glass at a distant street light. The distinctive shape of this background galaxy -- which is probably just forming -- has allowed astronomers to deduce that it has separate images at 4, 10, 11, and 12 o'clock, from the center of the cluster. A blue smudge near the cluster center is likely another image of the same background galaxy. In all, a recent analysis postulated that at least 33 images of 11 separate background galaxies are discernable. This spectacular photo of galaxy cluster CL0024+1654 from the Hubble Space Telescope was taken in November 2004. via NASA http://ift.tt/1MLh1Z0

2015/08/23

Little Planet Curiosity


A curious robot almost completely straddles this rocky little planet. Of course, the planet is really Mars and the robot is the car-sized Curiosity Rover, posing over its recent drilling target in the Marias Pass area of lower Mount Sharp. The 92 images used to assemble the little planet projection, a digitally warped and stitched mosaic covering 360x180 degrees, were taken by the rover's Mars Hand Lens Imager (MAHLI) during the Curiosity mission sol (martian day) 1065. That corresponds to 2015 August 5, three Earth years since Curiosity landed on the surface of the Red Planet. The composite selfie excludes images that show the rover's robotic arm and mount of the MAHLI camera itself, but their shadow is visible beneath. Check out this spectacular interactive version of Curiosity's sol 1065 panorama. via NASA http://ift.tt/1fxgZFq

2015/08/22

Sprites from Space


An old Moon and the stars of Orion rose above the eastern horizon on August 10. The Moon's waning crescent was still bright enough to be overexposed in this snapshot taken from another large satellite of planet Earth, the International Space Station. A greenish airglow traces the atmosphere above the limb of the planet's night. Below, city lights and lightning flashes from thunderstorms appear over southern Mexico. The snapshot also captures the startling apparition of a rare form of upper atmospheric lightning, a large red sprite caught above a lightning flash at the far right. While the space station's orbital motion causes the city lights to blur and trail during the exposure, the extremely brief flash of the red sprite is sharp. Now known to be associated with thunderstorms, much remains a mystery about sprites including how they occur, their effect on the atmospheric global electric circuit, and if they are somehow related to other upper atmospheric lightning phenomena such as blue jets or terrestrial gamma flashes. via NASA http://ift.tt/1Kz3Lk4

2015/08/21

A Hubble Cosmic Couple


Here we see the spectacular cosmic pairing of the star Hen 2-427 — more commonly known as WR 124 — and the nebula M1-67 which surrounds it. via NASA http://ift.tt/1U4ogtV

M27: Not a Comet


While hunting for comets in the skies above 18th century France, astronomer Charles Messier diligently kept a list of the things he encountered that were definitely not comets. This is number 27 on his now famous not-a-comet list. In fact, 21st century astronomers would identify it as a planetary nebula, but it's not a planet either, even though it may appear round and planet-like in a small telescope. Messier 27 (M27) is an excellent example of a gaseous emission nebula created as a sun-like star runs out of nuclear fuel in its core. The nebula forms as the star's outer layers are expelled into space, with a visible glow generated by atoms excited by the dying star's intense but invisible ultraviolet light. Known by the popular name of the Dumbbell Nebula, the beautifully symmetric interstellar gas cloud is over 2.5 light-years across and about 1,200 light-years away in the constellation Vulpecula. This impressive color composite highlights details within the well-studied central region and fainter, seldom imaged features in the nebula's outer halo. It incorporates broad and narrowband images recorded using filters sensitive to emission from sulfur, hydrogen and oxygen atoms. via NASA http://ift.tt/1Mz4ZQS

2015/08/20

Curiosity Low-Angle Self-Portrait at 'Buckskin' Drilling Site on Mount Sharp


This low-angle self-portrait of NASA's Curiosity Mars rover shows the vehicle above the "Buckskin" rock target, where the mission collected its seventh drilled sample. via NASA http://ift.tt/1NvoIS7

Central Cygnus Skyscape


In cosmic brush strokes of glowing hydrogen gas, this beautiful skyscape unfolds across the plane of our Milky Way Galaxy and the center of the northern constellation Cygnus the Swan. The featured image spans about six degrees. Bright supergiant star Gamma Cygni (Sadr) to the upper left of the image center lies in the foreground of the complex gas and dust clouds and crowded star fields. Left of Gamma Cygni, shaped like two luminous wings divided by a long dark dust lane is IC 1318, whose popular name is understandably the Butterfly Nebula. The more compact, bright nebula at the lower right is NGC 6888, the Crescent Nebula. Some distance estimates for Gamma Cygni place it at around 1,800 light-years while estimates for IC 1318 and NGC 6888 range from 2,000 to 5,000 light-years. via NASA http://ift.tt/1hLIP2m

2015/08/19

Testing on Deck


In 1939, President Franklin D. Roosevelt designated August 19 as National Aviation Day in honor of Orville Wright’s birthday, directing citizens to celebrate the day with activities that encourage an interest and appreciation for aviation. NASA's heritage in aviation research goes back more than 100 years. via NASA http://ift.tt/1PmyG6I

Announcing Comet Catalina


Will Comet Catalina become visible to the unaided eye? Given the unpredictability of comets, no one can say for sure, but it seems like a good bet. The comet was discovered in 2013 by observations of the Catalina Sky Survey. Since then, Comet C/2013 US10 (Catalina) has steadily brightened and is currently brighter than 8th magnitude, making it visible with binoculars and long-duration camera images. As the comet further approaches the inner Solar System it will surely continue to intensify, possibly becoming a naked eye object sometime in October and peaking sometime in late November. The comet will reside primarily in the skies of the southern hemisphere until mid-December, at which time its highly inclined orbit will bring it quickly into northern skies. Featured above, Comet Catalina was imaged last week sporting a green coma and two growing tails. via NASA http://ift.tt/1Mv7t2K

2015/08/18

Aurora's Colorful Veil Over Earth


NASA astronaut Scott Kelly shared this photograph on social media, taken from the International Space Station on August 15, 2015. Kelly wrote, "#Aurora trailing a colorful veil over Earth this morning. Good morning from @space_station! #YearInSpace" via NASA http://ift.tt/1EAdN2i

Andromeda Rising over the Alps


Have you ever seen the Andromeda galaxy? Although M31 appears as a faint and fuzzy blob to the unaided eye, the light you see will be over two million years old, making it likely the oldest light you ever will see directly. Now rising near a few hours after sunset from mid-latitude northern locations, Andromeda is rising earlier each night and will be visible to northerners all night long starting in September. The featured image captured Andromeda rising above the Italian Alps last month. As cool as it may be to see this neighboring galaxy to our Milky Way with your own eyes, long duration camera exposures can pick up many faint and breathtaking details. Recent data indicates that our Milky Way Galaxy will collide and coalesce with the slightly larger Andromeda galaxy in a few billion years. via NASA http://ift.tt/1JlwgXV

2015/08/17

Chasms on Dione


While not bursting with activity like its system satellite Enceladus, the surface of Dione is definitely not boring. via NASA http://ift.tt/1KrxyLw

M1: The Crab Nebula from Hubble


This is the mess that is left when a star explodes. The Crab Nebula, the result of a supernova seen in 1054 AD, is filled with mysterious filaments. The filaments are not only tremendously complex, but appear to have less mass than expelled in the original supernova and a higher speed than expected from a free explosion. The featured image, taken by the Hubble Space Telescope, is presented in three colors chosen for scientific interest. The Crab Nebula spans about 10 light-years. In the nebula's very center lies a pulsar: a neutron star as massive as the Sun but with only the size of a small town. The Crab Pulsar rotates about 30 times each second. via NASA http://ift.tt/1fhhDqi

2015/08/16

Perihelion Approaches


This dramatic outburst from the nucleus of Comet 67P/Churyumov-Gerasimenko occured on August 12, just hours before perihelion, its closest approach to the Sun. Completing an orbit of the Sun once every 6.45 years, perihelion distance for this periodic comet is about 1.3 astronomical units (AU), still outside the orbit of planet Earth (at 1 AU). The stark image of the 4 kilometer wide, double-lobed nucleus in bright sunlight and dark shadows was taken by the Rosetta spacecraft's science camera about 325 kilometers away. Too close to see the comet's growing tail, Rosetta maintains its ringside seat to watch the nucleus warm and become more active in coming weeks, as primordial ices sublimating from the surface produce jets of gas and dust. Of course, dust from the nucleus of periodic comet Swift-Tuttle, whose last perihelion passage was in 1992 at a distance of 0.96 AU, fell to Earth just this week. via NASA http://ift.tt/1PqWQ0H

2015/08/15

Comet Dust over Enchanted Rock


Dusty debris from periodic Comet Swift-Tuttle was swept up by planet Earth this week. Vaporized by their passage through the dense atmosphere at 59 kilometers per second, the tiny grains produced a stream of Perseid meteors. A bright, colorful Perseid meteor flash was captured during this 20 second exposure. It made its ephemeral appearance after midnight on August 12, in the moonless skies over the broad granite dome of Enchanted Rock State Natural Area, central Texas, USA. Below the Perseid meteor, trees stand in silhouette against scattered lights along the horizon and the faint Milky Way, itself cut by dark clouds of interstellar dust. via NASA http://ift.tt/1JWDAI4

2015/08/14

Hubble Sees a "Mess of Stars"


Bursts of pink and red, dark lanes of mottled cosmic dust, and a bright scattering of stars — this NASA/ESA Hubble Space Telescope image shows part of a messy barred spiral galaxy known as NGC 428. via NASA http://ift.tt/1WoQCD7

Moonless Meteors and the Milky Way


Have you watched the Perseid meteor shower? Though the annual shower's predicted peak was last night, meteor activity should continue tonight (August 13/14), best enjoyed by just looking up in clear, dark skies after midnight. Of course, this year's Perseid shower has the advantage of being active near the August 14 New Moon. Since the nearly New Moon doesn't rise before the morning twilight many fainter meteors are easier to spot until then, with no interference from bright moonlight. The Perseid meteor shower last occurred near a New Moon in 2013. That's when the exposures used to construct this image were made, under dark, moonless skies from Hvar Island off the coast of Croatia. The widefield composite includes 67 meteors streaming from the heroic constellation Perseus, the shower's radiant, captured during 2013 August 8-14 against a background of faint zodiacal light and the Milky Way. The next moonless Perseid meteor shower will be in August 2018. via NASA http://ift.tt/1JV4IHC

2015/08/13

Welding Preparations For Orion Spacecraft at Michoud Assembly Facility


At NASA’s Michoud Assembly Facility, engineers are welding together the Orion crew module pathfinder in preparation for the welding process set to begin later this summer on the Orion spacecraft for Exploration Mission-1. This pathfinder, including the barrel section shown here, is a full-scale version of the current spacecraft design. via NASA http://ift.tt/1HIG9Yn

Milky Way and Exploding Meteor


Tonight the Perseid Meteor Shower reaches its maximum. Grains of icy rock will streak across the sky as they evaporate during entry into Earth's atmosphere. These grains were shed from Comet Swift-Tuttle. The Perseids result from the annual crossing of the Earth through Comet Swift-Tuttle's orbit, and are typically the most active meteor shower of the year. Although it is hard to predict the level of activity in any meteor shower, in a clear dark sky an observer might see a meteor a minute. This year's Perseids occur just before a new Moon and so the relatively dark sky should make even faint meteors visible. Meteor showers in general are best be seen from a relaxing position, away from lights. Featured here is a meteor caught exploding two weeks ago above Austria next to the central band of our Milky Way Galaxy. via NASA http://ift.tt/1DLQVSs

2015/08/12

For Anniversary of Orbiter's Launch: Seasonal Flows in Mars' Valles Marineris


Among the many discoveries by NASA's Mars Reconnaissance Orbiter since the mission was launched on Aug. 12, 2005, are seasonal flows on some steep slopes. via NASA http://ift.tt/1WiS1uZ

A Blue Moon Halo over Antarctica


Have you ever seen a halo around the Moon? Such 22 degree rings around the Moon -- caused by ice crystals falling in the Earth's atmosphere -- are somewhat rare. OK, but have you ever seen a blue moon? Given the modern definition of blue moon -- the second full moon occurring in a calendar month -- these are also rare. What is featured above might therefore be considered doubly rare -- a halo surrounding a blue moon. The featured image was taken late last month near Zhongshan Station in Antarctica. Visible in the foreground are a power generating house and a snowmobile. What might seem to be stars in the background are actually illuminated snowflakes near the camera. via NASA http://ift.tt/1DJkFPU

2015/08/11

Good Morning From the International Space Station


NASA astronaut Scott Kelly took this photograph of a sunrise over the western United States and posted it to social media on Aug. 10, 2015. Kelly wrote, "#GoodMorning to those in the western #USA. Looks like there's a lot going on down there. #YearInSpace" via NASA http://ift.tt/1ICJwE0

A Sagittarius Triplet


These three bright nebulae are often featured in telescopic tours of the constellation Sagittarius and the crowded starfields of the central Milky Way. In fact, 18th century cosmic tourist Charles Messier cataloged two of them; M8, the large nebula left of center, and colorful M20 on the right. The third, NGC 6559, is above M8, separated from the larger nebula by a dark dust lane. All three are stellar nurseries about five thousand light-years or so distant. The expansive M8, over a hundred light-years across, is also known as the Lagoon Nebula. M20's popular moniker is the Trifid. Glowing hydrogen gas creates the dominant red color of the emission nebulae, with contrasting blue hues, most striking in the Trifid, due to dust reflected starlight. The colorful skyscape recorded with telescope and digital camera also includes one of Messier's open star clusters, M21, just above the Trifid. via NASA http://ift.tt/1EiMERv

2015/08/10

Darkness Descending


Saturn’s unusual appearance in this picture is a result of the planet being imaged via an infrared filter. via NASA http://ift.tt/1HBGnQN

HCG 87: A Small Group of Galaxies


Sometimes galaxies form groups. For example, our own Milky Way Galaxy is part of the Local Group of Galaxies. Small, compact groups, like Hickson Compact Group 87 (HCG 87) shown above, are interesting partly because they slowly self-destruct. Indeed, the galaxies of HCG 87 are gravitationally stretching each other during their 100-million year orbits around a common center. The pulling creates colliding gas that causes bright bursts of star formation and feeds matter into their active galaxy centers. HCG 87 is composed of a large edge-on spiral galaxy visible near the image center, an elliptical galaxy visible to its right, and a spiral galaxy visible near the top. The small spiral near the center might be far in the distance. Several stars from our Galaxy are also visible in the foreground. Studying groups like HCG 87 allows insight into how all galaxies form and evolve. via NASA http://ift.tt/1OYEq6J

2015/08/09

Curiosity s View


By planet Earth's calendar, the Curiosity Mars Rover reached its 3rd anniversary on the surface of the Red Planet on August 6. To celebrate, gaze across this dramatic panoramic view of diverse terrain typical of the rover's journey to the layered slopes of Aeolis Mons, also known as Mount Sharp. Recorded with Curiosity's Mast Camera instrument, the scene looks south across gravel, sand ripples, and boulders toward rounded buttes. In the background, higher layers at left are toward the southeast, with southwest at panorama right. The individual images composing the view were taken on Curiosity's mission sols (martian days) 952 and 953 since the rover's landing on August 6, 2012. via NASA http://ift.tt/1UuFz9B

2015/08/08

Full Earth, Full Moon


The Moon was new on July 16. Its familiar nearside facing the surface of planet Earth was in shadow. But on that date a million miles away, the Deep Space Climate Observatory (DSCOVR) spacecraft's Earth Polychromatic Imaging Camera (EPIC) captured this view of an apparently Full Moon crossing in front of a Full Earth. In fact, seen from the spacecraft's position beyond the Moon's orbit and between Earth and Sun, the fully illuminated lunar hemisphere is the less familiar farside. Only known since the dawn of the space age, the farside is mostly devoid of dark lunar maria that sprawl across the Moon's perpetual Earth-facing hemisphere. Only the small dark spot of the farside's Mare Moscoviense (Sea of Moscow) is clear, at the upper left. Planet Earth's north pole is near 11 o'clock, with the North America visited by Hurricane Dolores near center. Slight color shifts are visible around the lunar edge, an artifact of the Moon's motion through the field caused by combining the camera's separate exposures taken in quick succession through different color filters. While monitoring the Earth and solar wind for space weather forcasts, about twice a year DSCOVR can capture similar images of Moon and Earth together as it crosses the orbital plane of the Moon. via NASA http://ift.tt/1MReigo

2015/08/07

Hubble Finds a Little Gem


This colorful bubble is a planetary nebula called NGC 6818, also known as the Little Gem Nebula. The rich glow of the cloud is just over half a light-year across — humongous compared to its tiny central star — but still a little gem on a cosmic scale. via NASA http://ift.tt/1K7fc2m

Stereo Pluto


These two detailed, true color images of Pluto were captured during the historic New Horizons flyby last month. With slightly different perspectives on the now recognizeable surface features they are presented in this first high quality stereo pair intended for viewing by denizens of planet Earth. The left hand image (left eye) is a mosaic recorded when the spacecraft was about 450,000 kilometers from Pluto. The right single image was acquired earlier, a last full look before the spacecraft's closest approach. Despite a difference in resolution, the pair combine for a stunning 3D perception of the distant, underworldly terrain. via NASA http://ift.tt/1KS4Shi

2015/08/06

Stormy Seas in Sagittarius


This new NASA/ESA Hubble Space Telescope image shows the center of the Lagoon Nebula, an object with a deceptively tranquil name, in the constellation of Sagittarius. The region is filled with intense winds from hot stars, churning funnels of gas, and energetic star formation, all embedded within an intricate haze of gas and pitch-dark dust. via NASA http://ift.tt/1gdKYmi

X ray Echoes from Circinus X 1


Circinus X-1 is an X-ray binary star known for its erratic variability. In the bizarre Circinus X-1 system, a dense neutron star, the collapsed remnant of a supernova explosion, orbits with a more ordinary stellar companion. Observations of the X-ray binary in months following an intense X-ray flare from the source in 2013 progressively revealed striking concentric rings - bright X-ray light echoes from four intervening clouds of interstellar dust. In this X-ray/optical composite, the swaths of Chandra Observatory X-ray image data showing partial outlines of the rings are in false colors. Remarkably, timing the X-ray echoes, along with known distances to the interstellar dust clouds, determines the formerly highly uncertain distance to Circinus X-1 itself to be 30,700 light-years. via NASA http://ift.tt/1MN5Hdu

2015/08/05

Testing Hardware for Growing Plants and Vegetables in Space


Astronauts on the International Space Station continue testing the VEGGIE hardware for growing vegetables and plants in space. VEGGIE provides lighting and nutrient supply for plants in the form of a low-cost growth chamber and planting "pillows" -- helping provide nutrients for the root system. via NASA http://ift.tt/1E8ffZG

Virgo Cluster Galaxies


Well over a thousand galaxies are known members of the Virgo Cluster, the closest large cluster of galaxies to our own local group. In fact, the galaxy cluster is difficult to appreciate all at once because it covers such a large area on the sky. This careful wide-field mosaic of telescopic images clearly records the central region of the Virgo Cluster through faint foreground dust clouds lingering above the plane of our own Milky Way galaxy. The cluster's dominant giant elliptical galaxy M87, is just below and to the left of the frame center. To the right of M87 is a string of galaxies known as Markarian's Chain. A closer examination of the image will reveal many Virgo cluster member galaxies as small fuzzy patches. Sliding your cursor over the image will label the larger galaxies using NGC catalog designations. Galaxies are also shown with Messier catalog numbers, including M84, M86, and prominent colorful spirals M88, M90, and M91. On average, Virgo Cluster galaxies are measured to be about 48 million light-years away. The Virgo Cluster distance has been used to give an important determination of the Hubble Constant and the scale of the Universe. via NASA http://ift.tt/1g355DJ

2015/08/04

Algae Bloom in Lake St. Clair


On July 28, 2015, the Operational Land Imager (OLI) on the Landsat 8 satellite captured images of algal blooms around the Great Lakes, visible as swirls of green in this image of Lake St. Clair and in western Lake Erie. via NASA http://ift.tt/1VZie1w

A Proton Arc Over Lake Superior


The setting had been picked out -- all that was needed was an aurora. And late last August, forecasts predicted that an otherwise beautiful night sky would be lit up with auroral green. Jumping into his truck, the astrophotographer approached his secret site -- but only after a five hour drive across the rural Upper Peninsula of Michigan. What he didn't know was that his luck was just beginning. While setting up for the image, a proton arc -- a rare type of aurora -- appeared. The red arc lasted only about 15 minutes, but that was long enough to capture in a 30-second exposure. As the name indicates, proton arcs are caused not by electrons but by more massive protons that bombard the Earth's atmosphere following an energetic event on the Sun. In the featured image, the yellow lights on the horizon are the city lights of Marquette, Michigan, USA. The blue and yellow rocks in the Lake Superior foreground are lit by a LED flashlight. Also captured, to the left of the red proton arc, was the band of our Milky Way Galaxy. via NASA http://ift.tt/1fYAdUS

2015/08/03

Apollo 17 at Shorty Crater


On the Moon, it is easy to remember where you parked. In December of 1972, Apollo 17 astronauts Eugene Cernan and Harrison Schmitt spent about 75 hours on the Moon in the Taurus-Littrow valley, while colleague Ronald Evans orbited overhead. This sharp image was taken by Cernan as he and Schmitt roamed the valley floor. The image shows Schmitt on the left with the lunar rover at the edge of Shorty Crater, near the spot where geologist Schmitt discovered orange lunar soil. The Apollo 17 crew returned with 110 kilograms of rock and soil samples, more than was returned from any of the other lunar landing sites. Now forty three years later, Cernan and Schmitt are still the last to walk on the Moon. via NASA http://ift.tt/1IwRkUL

2015/08/02

Space Station Lunar Transit


The International Space Station, with a crew of six onboard, is seen in silhouette as it transits the moon at roughly five miles per second, Sunday, Aug. 2, 2015, Woodford, VA. via NASA http://ift.tt/1IRWKQp