2014/10/31

Specular Spectacular



This near-infrared, color mosaic from NASA's Cassini spacecraft shows the sun glinting off of Titan's north polar seas. While Cassini has captured, separately, views of the polar seas (see PIA17470) and the sun glinting off of them (see PIA12481 and PIA18433) in the past, this is the first time both have been seen together in the same view. The sunglint, also called a specular reflection, is the bright area near the 11 o'clock position at upper left. This mirror-like reflection, known as the specular point, is in the south of Titan's largest sea, Kraken Mare, just north of an island archipelago separating two separate parts of the sea. This particular sunglint was so bright as to saturate the detector of Cassini's Visual and Infrared Mapping Spectrometer (VIMS) instrument, which captures the view. It is also the sunglint seen with the highest observation elevation so far -- the sun was a full 40 degrees above the horizon as seen from Kraken Mare at this time -- much higher than the 22 degrees seen in PIA18433. Because it was so bright, this glint was visible through the haze at much lower wavelengths than before, down to 1.3 microns. The southern portion of Kraken Mare (the area surrounding the specular feature toward upper left) displays a "bathtub ring" -- a bright margin of evaporate deposits -- which indicates that the sea was larger at some point in the past and has become smaller due to evaporation. The deposits are material left behind after the methane & ethane liquid evaporates, somewhat akin to the saline crust on a salt flat. The highest resolution data from this flyby -- the area seen immediately to the right of the sunglint -- cover the labyrinth of channels that connect Kraken Mare to another large sea, Ligeia Mare. Ligeia Mare itself is partially covered in its northern reaches by a bright, arrow-shaped complex of clouds. The clouds are made of liquid methane droplets, and could be actively refilling the lakes with rainfall. The view was acquired during Cassini's August 21, 2014, flyby of Titan, also referred to as "T104" by the Cassini team. The view contains real color information, although it is not the natural color the human eye would see. Here, red in the image corresponds to 5.0 microns, green to 2.0 microns, and blue to 1.3 microns. These wavelengths correspond to atmospheric windows through which Titan's surface is visible. The unaided human eye would see nothing but haze, as in PIA12528. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology, Pasadena, manages the mission for NASA's Science Mission Directorate in Washington. The VIMS team is based at the University of Arizona in Tucson. More information about Cassini is available at http://ift.tt/ZjpQgB and http://ift.tt/Jcddhk. Image Credit: NASA/JPL-Caltech/University of Arizona/University of Idaho via NASA http://ift.tt/1s0kCnh

A Spectre in the Eastern Veil



Frightening forms and scary faces are a mark of the Halloween season. They also haunt this cosmic close-up of the eastern Veil Nebula. The Veil Nebula itself is a large supernova remnant, the expanding debris cloud from the death explosion of a massive star. While the Veil is roughly circular in shape and covers nearly 3 degrees on the sky in the constellation Cygnus, this portion of the eastern Veil spans only 1/2 degree, about the apparent size of the Moon. That translates to 12 light-years at the Veil's estimated distance, a reassuring 1,400 light-years from planet Earth. In the composite of image data recorded through broad and narrow band filters, emission from hydrogen atoms in the remnant is shown in red with strong emission from oxygen atoms in blue-green hues. Of course, in the western part of the Veil lies another seasonal apparition, the Witch's Broom. via NASA http://ift.tt/1q1lTtw

2014/10/30

Fifteen Years of NASA's Chandra X-ray Observatory



This Chandra X-ray Observatory image of the Hydra A galaxy cluster was taken on Oct. 30, 1999, with the Advanced CCD Imaging Spectrometer (ACIS) in an observation that lasted about six hours. Hydra A is a galaxy cluster that is 840 million light years from Earth. The cluster gets its name from the strong radio source, Hydra A, that originates in a galaxy near the center of the cluster. Optical observations show a few hundred galaxies in the cluster. Chandra X-ray observations reveal a large cloud of hot gas that extends throughout the cluster. The gas cloud is several million light years across and has a temperature of about 40 million degrees in the outer parts decreasing to about 35 million degrees in the inner region. NASA's Chandra X-ray Observatory was launched into space fifteen years ago aboard the Space Shuttle Columbia. Since its deployment on July 23, 1999, Chandra has helped revolutionize our understanding of the universe through its unrivaled X-ray vision. Chandra, one of NASA's current "Great Observatories," along with the Hubble Space Telescope and Spitzer Space Telescope, is specially designed to detect X-ray emission from hot and energetic regions of the universe. Image Credit: NASA/CXC/SAO via NASA http://ift.tt/1DCG9ru

Iridescent Cloud Edge Over Colorado



Sometimes your eclipse viewing goes bad in an interesting way. While watching and photographing last Thursday's partial solar eclipse, a popular astronomy blogger suffered through long periods of clouds blocking the Sun. Unexpectedly, however, a nearby cloud began to show a rare effect: iridescence. Frequently part of a more familiar solar corona effect, iridescence is the diffraction of sunlight around a thin screen of nearly uniformly-sized water droplets. Different colors of the sunlight become deflected by slightly different angles and so come to the observer from slightly different directions. This display, featured here, was quite bright and exhibited an unusually broad range of colors. On the right, the contrails of an airplane are also visible. via NASA http://ift.tt/1tJ7ad5

2014/10/29

Sunrise From the International Space Station



NASA astronaut Reid Wiseman posted this image of a sunrise, captured from the International Space Station, to social media on Oct. 29, 2014. Wiseman wrote, "Not every day is easy. Today was a tough one." Wiseman was referring to the loss on Oct. 28 of the Orbital Sciences Corporation Antares rocket and Cygnus spacecraft, moments after launch at NASA's Wallops Flight Facility in Virginia. The Cygnus spacecraft was filled with about 5,000 pounds of supplies slated for the International Space Station, including science experiments, experiment hardware, spare parts, and crew provisions. The station crew is in no danger of running out of food or other critical supplies. Image Credit: NASA/Reid Wiseman via NASA http://ift.tt/1rAyUKd

The Warm Glow of Mach 3



The Flight Loads Laboratory at NASA's Armstrong Flight Research Center is celebrating 50 years. It sprang into existence during the era of the X-15 rocket plane and the YF-12 and SR-71 Blackbirds, and was dedicated to testing the latest in high-speed flight. In this image from 1971, the YF-12 forebody's radiant heating system is being tested at the Flight Loads Laboratory under conditions experienced at Mach 3, or three times the speed of sound, over 2,000 miles an hour. Eventually the entire airframe was tested in the lab, always with the goal to collect data, validate parts and reduce risk to the aircraft and the pilots who flew them. Image credit: NASA Read More About the Flight Loads Laboratory Anniversary Read About Modern Aeronautics Testing in the Flight Loads Laboratory via NASA http://ift.tt/1zJyN90

Retrograde Mars



Why would Mars appear to move backwards? Most of the time, the apparent motion of Mars in Earth's sky is in one direction, slow but steady in front of the far distant stars. About every two years, however, the Earth passes Mars as they orbit around the Sun. During the most recent such pass starting late last year, Mars as usual, loomed large and bright. Also during this time, Mars appeared to move backwards in the sky, a phenomenon called retrograde motion. Featured here is a series of images digitally stacked so that all of the stars coincide. Here, Mars appears to trace out a narrow loop in the sky. At the center of the loop, Earth passed Mars and the retrograde motion was the highest. Retrograde motion can also be seen for other Solar System planets. via NASA http://ift.tt/1DV3Du8

2014/10/28

Here’s Looking at You: Spooky Shadow Gives Jupiter a Giant Eye



This trick that the planet is looking back at you is actually a Hubble treat: An eerie, close-up view of Jupiter, the biggest planet in our solar system. Hubble was monitoring changes in Jupiter’s immense Great Red Spot (GRS) storm on April 21, 2014, when the shadow of the Jovian moon, Ganymede, swept across the center of the storm. This gave the giant planet the uncanny appearance of having a pupil in the center of a 10,000 mile-diameter “eye.” For a moment, Jupiter “stared” back at Hubble like a one-eyed giant Cyclops. Click on the image to view Jupiter from a distance. Image Credit: NASA/ESA/A. Simon (Goddard Space Flight Center) Caption: Ray Villard, Space Science Telescope Institute Acknowledgment: C. Go and the Hubble Heritage Team (STScI/AURA) via NASA http://ift.tt/1323kAq

Plane, Clouds, Moon, Spots, Sun



What's that in front of the Sun? The closest object is an airplane, visible just below the Sun's center and caught purely by chance. Next out are numerous clouds in Earth's atmosphere, creating a series of darkened horizontal streaks. Farther out is Earth's Moon, seen as the large dark circular bite on the upper right. Just above the airplane and just below the Sun's surface are sunspots. The main sunspot group captured here, AR 2192, is one of the largest ever recorded and has been crackling and bursting with flares since it came around the edge of the Sun early last week. Taken last Thursday, this show of solar silhouettes was unfortunately short-lived. Within a few seconds the plane flew away. Within a few minutes the clouds drifted off. Within a few hours the partial solar eclipse of the Sun by the Moon was over. Only the sunspot group remains, but within a few more days even AR 2192 will disappear around the edge of the Sun. Fortunately, when it comes to the Sun, even unexpected alignments are surprisingly frequent. via NASA http://ift.tt/1oNEuOT

2014/10/27

Orbital Antares Rocket at the Launch Pad



The Orbital Sciences Corporation Antares rocket, with the Cygnus spacecraft onboard, is seen on launch Pad-0A, Sunday, Oct. 26, 2014, at NASA's Wallops Flight Facility in Virginia. The Antares will launch with the Cygnus spacecraft filled with over 5,000 pounds of supplies for the International Space Station, including science experiments, experiment hardware, spare parts, and crew provisions. The Orbital-3 mission is Orbital Sciences' third contracted cargo delivery flight to the space station for NASA. Launch is scheduled for Monday, Oct. 27 at 6:45 p.m. EDT. > Latest: Orbital Launch Blog Image Credit: NASA/Joel Kowsky via NASA http://ift.tt/1zzRTyz

Too Close to a Black Hole



What would you see if you went right up to a black hole? Featured is a computer generated image highlighting how strange things would look. The black hole has such strong gravity that light is noticeably bent towards it - causing some very unusual visual distortions. Every star in the normal frame has at least two bright images - one on each side of the black hole. Near the black hole, you can see the whole sky - light from every direction is bent around and comes back to you. The original background map was taken from the 2MASS infrared sky survey, with stars from the Henry Draper catalog superposed. Black holes are thought to be the densest state of matter, and there is indirect evidence for their presence in stellar binary systems and the centers of globular clusters, galaxies, and quasars. via NASA http://ift.tt/1t4wS8Q

2014/10/26

Antares Rocket at Sunrise



The Orbital Sciences Corporation Antares rocket, with the Cygnus spacecraft onboard, is seen on launch Pad-0A during sunrise, Sunday, Oct. 26, 2014, at NASA's Wallops Flight Facility in Virginia. The Antares will launch with the Cygnus spacecraft filled with over 5,000 pounds of supplies for the International Space Station, including science experiments, experiment hardware, spare parts, and crew provisions. The Orbital-3 mission is Orbital Sciences' third contracted cargo delivery flight to the space station for NASA. Launch is scheduled for Monday, Oct. 27 at 6:45 p.m. EDT.Image Credit: NASA/Joel Kowsky via NASA http://ift.tt/1zw8Auu

Sunspots and Solar Eclipse



A New Moon joined giant sunspot group AR 2192 to dim the bright solar disk during Thursday's much anticipated partial solar eclipse. Visible from much of North America, the Moon's broad silhouette is captured in this extreme telephoto snapshot near eclipse maximum from Santa Cruz, California. About the size of Jupiter, the remarkable AR 2192 itself darkens a noticeable fraction of the Sun, near center and below the curved lunar limb. As the sunspot group slowly rotates across the Sun and out of view in the coming days its activity is difficult to forecast. But the timing of solar eclipses is easier to predict. The next will be a total solar eclipse on March 20, 2015. via NASA http://ift.tt/1skb2KM

2014/10/25

AR 2192: Giant on the Sun



As you (safely!) watched the progress of yesterday's partial solar eclipse, you probably also spotted a giant sunspot group. Captured in this sharp telescopic image from October 22nd the complex AR 2192 is beautiful to see, a sprawling solar active region comparable in size to the diameter of Jupiter. Like other smaller sunspot groups, AR 2192 is now crossing the Earth-facing side of the Sun and appears dark in visible light because it is cooler than the surrounding surface. Still, the energy stored in the region's twisted magnetic fields is enormous and has already generated powerful explosions, including two X-class solar flares this week. Coronal mass ejections (CMEs) associated with the flares have not affected planet Earth, so far. The forecast for further activity from AR 2192 is still significant though, as it swings across the center of the solar disk and Earth-directed CMEs become possible. via NASA http://ift.tt/1tPQWQ6

2014/10/24

Galaxies in Pegasus



This wide, sharp telescopic view reveals galaxies scattered beyond the stars and faint dust nebulae of the Milky Way at the northern boundary of the high-flying constellation Pegasus. Prominent at the upper right is NGC 7331. A mere 50 million light-years away, the large spiral is one of the brighter galaxies not included in Charles Messier's famous 18th century catalog. The disturbed looking group of galaxies at the lower left is well-known as Stephan's Quintet. About 300 million light-years distant, the quintet dramatically illustrates a multiple galaxy collision, its powerful, ongoing interactions posed for a brief cosmic snapshot. On the sky, the quintet and NGC 7331 are separated by about half a degree. via NASA http://ift.tt/1mZrII2

2014/10/22

James Webb Space Telescope's Heart Survives Deep Freeze Test



After 116 days of being subjected to extremely frigid temperatures like that in space, the heart of the James Webb Space Telescope, the Integrated Science Instrument Module (ISIM) and its sensitive instruments, emerged unscathed from the thermal vacuum chamber at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. The Webb telescope's images will reveal the first galaxies forming 13.5 billion years ago. The telescope will also pierce through interstellar dust clouds to capture stars and planets forming in our own galaxy. At the telescope's final destination in space, one million miles away from Earth, it will operate at incredibly cold temperatures of -387 degrees Fahrenheit, or 40 degrees Kelvin. This is 260 degrees Fahrenheit colder than any place on the Earth’s surface has ever been. To create temperatures that cold on Earth, the team uses the massive thermal vacuum chamber at Goddard called the Space Environment Simulator, or SES, that duplicates the vacuum and extreme temperatures of space. This 40-foot-tall, 27-foot-diameter cylindrical chamber eliminates the tiniest trace of air with vacuum pumps and uses liquid nitrogen and even colder liquid helium to drop the temperature simulating the space environment. The James Webb Space Telescope is the scientific successor to NASA's Hubble Space Telescope. It will be the most powerful space telescope ever built. Webb is an international project led by NASA with its partners, the European Space Agency and the Canadian Space Agency. > More: NASA Webb's Heart Survives Deep Freeze Test Image Credit: NASA/Chris Gunn via NASA http://ift.tt/1yYhfoh

2014/10/21

Comet Siding Spring Passes Mars



Yesterday, a comet passed very close to Mars. In fact, Comet C/2013 A1 (Siding Spring) passed closer to the red planet than any comet has ever passed to Earth in recorded history. To take advantage of this unique opportunity to study the close interaction of a comet and a planet, humanity currently has five active spacecraft orbiting Mars: NASA's MAVEN, MRO, Mars Odyssey, as well as ESA's Mars Express, and India's Mars Orbiter. Most of these spacecraft have now sent back information that they have not been damaged by small pieces of the passing comet. These spacecraft, as well as the two active rovers on the Martian surface -- NASA's Opportunity and Curiosity -- have taken data and images that will be downloaded to Earth for weeks to come and likely studied for years to come. The featured image taken yesterday, however, was not taken from Mars but from Earth and shows Comet Siding Spring on the lower left as it passed Mars, on the upper right. via NASA http://ift.tt/11Um6sU

2014/10/20

Extreme Ultraviolet Image of a Significant Solar Flare



The sun emitted a significant solar flare on Oct. 19, 2014, peaking at 1:01 a.m. EDT. NASA's Solar Dynamics Observatory, which is always observing the sun, captured this image of the event in extreme ultraviolet wavelength of 131 Angstroms – a wavelength that can see the intense heat of a flare and that is typically colorized in teal. This flare is classified as an X1.1-class flare. X-class denotes the most intense flares, while the number provides more information about its strength. An X2 flare is twice as intense as an X1, and an X3 is three times as intense. Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however -- when intense enough -- they can disturb the atmosphere in the layer where GPS and communications signals travel. > More: NASA's SDO Observes an X-class Solar Flare Image Credit: NASA/Solar Dynamics Observatory via NASA http://ift.tt/1rXNFXo

Comet McNaught Over New Zealand



Comet McNaught was perhaps the most photogenic comet of modern times -- from Earth. After making quite a show in the northern hemisphere in early January of 2007, the comet moved south and developed a long and unusual dust tail that dazzled southern hemisphere observers. In late January 2007, Comet McNaught was captured between Mount Remarkable and Cecil Peak in this spectacular image taken from Queenstown, South Island, New Zealand. The bright comet dominates the right part of the above image, while the central band of our Milky Way Galaxy dominates the left. Careful inspection of the image will reveal a meteor streak just to the left of the comet. Today, Comet Siding Spring may become the most photogenic comet of modern times -- from Mars. via NASA http://ift.tt/1ohO7Fd

2014/10/19

Hubble Time-lapse Catches Stunning Stellar Explosion (VIDEO)




The Hubble Space Telescope captured the stellar explosion of V838 Monocerotis over the course of four years. Then scientists combined the footage into this stunning time-lapse. The event was first observed in early 2002. The first initial flash of light was seen in January. After it began to dim, it suddenly began to brighten again (in infrared wavelengths). This brightening took place towards the start of March. After that brightening faded, another one happened in April.

This was a little confusing.

Nothing like this has ever been observed before, but there are five hypotheses about what happened. Some think that this event was just a unique supernova. Others assert that the event occurred because of a stellar collision. This is known as a mergeburst, in which two main sequence stars collide. The other ideas are a planetary capture event, during which a star begins to consume planets in its system, and a helium flash or a thermonuclear event. The ultimate answer is currently unknown. Regardless of what caused it, the result is simply stunning.

Melotte 15 in the Heart



Cosmic clouds form fantastic shapes in the central regions of emission nebula IC 1805. The clouds are sculpted by stellar winds and radiation from massive hot stars in the nebula's newborn star cluster, Melotte 15. About 1.5 million years young, the cluster stars are toward the right in this colorful skyscape, along with dark dust clouds in silhouette against glowing atomic gas. A composite of narrowband and broadband telescopic images, the view spans about 30 light-years and includes emission from ionized hydrogen, sulfur, and oxygen atoms mapped to green, red, and blue hues in the popular Hubble Palette. Wider field images reveal that IC 1805's simpler, overall outline suggests its popular name - The Heart Nebula. IC 1805 is located about 7,500 light years away toward the boastful constellation Cassiopeia. via NASA http://ift.tt/1sSWBCx

2014/10/18

Messier 6 and Comet Siding Spring



This looks like a near miss but the greenish coma and tail of Comet Siding Spring (C/2013 A1) are really 2,000 light-years or so away from the stars of open cluster Messier 6. They do appear close together though, along the same line-of-sight in this gorgeous October 9th skyscape toward the constellation Scorpius. Still, on Sunday, October 19th this comet really will be involved in a near miss, passing within only 139,500 kilometers of planet Mars. That's about 10 times closer than any known comet flyby of planet Earth, and nearly one third the Earth-Moon distance. While an impact with the nucleus is not a threat the comet's dust, moving with a speed of about 56 kilometers per second relative to the Red Planet, and outskirts of its gaseous coma could interact with the thin Martian atmosphere. Of course, the comet's close encounter will be followed intently by spacecraft in Martian orbit and rovers on the surface. via NASA http://ift.tt/1piHLQG

2014/10/17

Rosetta's Selfie



This Rosetta spacecraft selfie was snapped on October 7th. At the time the spacecraft was about 472 million kilometers from planet Earth, but only 16 kilometers from the surface of comet 67P/Churyumov-Gerasimenko. Looming beyond the spacecraft near the top of the frame, dust and gas stream away from the comet's curious double-lobed nucleus and bright sunlight glints off one of Rosetta's 14 meter long solar arrays. In fact, two exposures, one short and one long, were combined to record the dramatic high contrast scene using the CIVA camera system on Rosetta's still-attached Philae lander. Its chosen primary landing site is visible on the smaller lobe of the nucleus. This is the last image anticipated from Philae's cameras before the lander separates from Rosetta on November 12. Shortly after separation Philae will take another image looking back toward the orbiter, and begin its descent to the nucleus of the comet. via NASA http://ift.tt/1rwxZu2

2014/10/16

Mysterious Changing feature on Titan



What is that changing object in a cold hydrocarbon sea of Titan? Radar images from the robotic Cassini spacecraft orbiting Saturn have been recording the surface of the cloud-engulfed moon Titan for years. When imaging the flat -- and hence radar dark -- surface of the methane and ethane lake called Ligeia Mare, an object appeared in 2013 just was not there in 2007. Subsequent observations in 2014 found the object remained -- but had changed! The featured image shows how the 20-km long object has appeared and evolved. Current origin speculative explanations include bubbling foam and floating solids, but no one is sure. Future observations may either resolve the enigma or open up more speculation. via NASA http://ift.tt/1sJMQI0

2014/10/15

Wiseman and Wilmore Spacewalk Preparations



Flight Engineers Reid Wiseman and Barry Wilmore spent most of the day on Tuesday, Oct. 14 completing preparations for their 6 ½-hour Oct. 15 spacewalk. The two astronauts set up their spacesuits and tools in the equipment lock of the Quest airlock. Flight Engineer Alexander Gerst of the European Space Agency, who is coordinating spacewalk activities from inside the station, joined Wiseman and Wilmore for a review of spacewalk procedures. During today’s spacewalk, the astronauts will venture out to the starboard truss of the station to remove and replace a power regulator known as a sequential shunt unit, which failed back in mid-May. The two spacewalkers also will move TV and camera equipment in preparation for the relocation of the Leonardo Permanent Multipurpose Module to accommodate the installation of new docking adapters for future commercial crew vehicles. This photo was taken on Oct. 1, 2014. Image Credit: NASA via NASA http://ift.tt/1rbUjJo

Auroral Corona over Norway



Higher than the highest mountain lies the realm of the aurora. Auroras rarely reach below 60 kilometers, and can range up to 1000 kilometers. Aurora light results from energetic electrons and protons striking atoms and molecules in the Earth's atmosphere. Somewhat uncommon, an auroral corona appears as a center point for a surrounding display and may occur when an aurora develops directly overhead, or when auroral rays are pointed nearly toward the observer. This picturesque but brief green and purple aurora exhibition occurred last month high above Kvaløya, Tromsø, Norway. The Sessøyfjorden fjord runs through the foreground, while numerous stars are visible far in the distance. via NASA http://ift.tt/1vpkEeB

2014/10/14

Stuck on the Rings



Like a drop of dew hanging on a leaf, Tethys appears to be stuck to the A and F rings from this perspective. Tethys (660 miles, or 1,062 kilometers across), like the ring particles, is composed primarily of ice. The gap in the A ring through which Tethys is visible is the Keeler gap, which is kept clear by the small moon Daphnis (not visible here). This view looks toward the Saturn-facing hemisphere of Tethys. North on Tethys is up and rotated 43 degrees to the right. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on July 14, 2014. The view was acquired at a distance of approximately 1.1 million miles (1.8 million kilometers) from Tethys and at a Sun-Tethys-spacecraft, or phase, angle of 22 degrees. Image scale is 7 miles (11 kilometers) per pixel. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo. For more information about the Cassini-Huygens mission visit http://ift.tt/ZjpQgB and http://ift.tt/Jcddhk . The Cassini imaging team homepage is at http://ciclops.org . Credit: NASA/JPL-Caltech/Space Science Institute via NASA http://ift.tt/11j90Fx

2014/10/13

The Helix Nebula from Blanco and Hubble



How did a star create the Helix nebula? The shapes of planetary nebula like the Helix are important because they likely hold clues to how stars like the Sun end their lives. Observations by the orbiting Hubble Space Telescope and the 4-meter Blanco Telescope in Chile, however, have shown the Helix is not really a simple helix. Rather, it incorporates two nearly perpendicular disks as well as arcs, shocks, and even features not well understood. Even so, many strikingly geometric symmetries remain. How a single Sun-like star created such beautiful yet geometric complexity is a topic of research. The Helix Nebula is the nearest planetary nebula to Earth, lies only about 700 light years away toward the constellation of Aquarius, and spans about 3 light-years. via NASA http://ift.tt/1sAFDc9

2014/10/12

Eclipse at Moonrise



As the Moon rose and the Sun set on October 8, a lunar eclipse was in progress seen from Chongqing, China. Trailing through this composite time exposure, the rising Moon began as a dark reddened disk in total eclipse near the eastern horizon. Steadily climbing above the populous city's colorful lights along the Yangtze River, the moontrail grows brighter and broader, until a bright Full Moon emerged from the Earth's shadow in evening skies. Although lunar eclipses are not always total ones, this eclipse, along with last April's lunar eclipse, were the first two of four consecutive total lunar eclipses, a series known as a tetrad. The final two eclipses of this tetrad will occur in early April and late September 2015. via NASA http://ift.tt/1yjIEAS

2014/10/11

Moons at Opposition



From the early hours of October 8, over the Santa Cruz Mountains near Los Gatos, California, the totally eclipsed Moon shows a range of color across this well-exposed telescopic view of the lunar eclipse. Of course, a lunar eclipse can only occur when the Moon is opposite the Sun in Earth's sky and gliding through the planet's shadow. But also near opposition during this eclipse, and remarkably only half a degree or so from the lunar limb, distant Uranus is faint but easy to spot at the lower right. Fainter still are the ice giant's moons. To find them, slide your cursor over the image (or just follow this link) to check out a longer exposure. While even the darkened surface of our eclipsed Moon will be strongly overexposed, Uranus moons Titania, Oberon, and Umbriel can just be distinguished as faint pinpricks of light. via NASA http://ift.tt/1oWkwf7

2014/10/10

Eclipse at Moonset



The Pacific Ocean and Chilean coast lie below this sea of clouds. Seen through the subtle colors of the predawn sky a lunar eclipse is in progress above, the partially eclipsed Moon growing dark. The curved edge of planet Earth's shadow still cuts across the middle of the lunar disk as the Moon sinks lower toward the western horizon. In fact, from this southern hemisphere location as well as much of eastern North America totality, the Moon completely immersed within Earth's shadow, began near the time of moonset and sunrise on October 8. From farther west the total phase could be followed for almost an hour though, the darker reddened Moon still high in the night sky. via NASA http://ift.tt/1vOiRxf

2014/10/09

Super Typhoon Vongfong in the Philippine Sea



On Oct. 9, 2014 at 04:25 UTC (12:25 a.m. EDT), the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument aboard NASA's Aqua satellite captured this view of Super Typhoon Vongfong in the Philippine Sea. > Two NASA Satellites Get Data on Category 5 Super Typhoon Vongfong Image Credit: NASA Goddard MODIS Rapid Response Team via NASA http://ift.tt/1skPG4Z

NGC 6823: Cloud Sculpting Star Cluster



Star cluster NGC 6823 is slowly turning gas clouds into stars. The center of the open cluster, visible on the upper right, formed only about two million years ago and is dominated in brightness by a host of bright young blue stars. Some outer parts of the cluster, visible in the featured image's center as the stars and pillars of emission nebula NGC 6820, contain even younger stars. The huge pillars of gas and dust likely get their elongated shape by erosion from hot radiation emitted from the brightest cluster stars. Striking dark globules of gas and dust are also visible across the upper left of the featured image. Open star cluster NGC 6823 spans about 50 light years and lies about 6000 light years away toward the constellation of the Fox (Vulpecula). via NASA http://ift.tt/1qexgxh

2014/10/08

Astronaut Reid Wiseman on the First Spacewalk of Expedition 41



On Oct. 7, NASA astronaut Reid Wiseman (pictured here) and European Space Agency astronaut Alexander Gerst completed the first of three spacewalks for the Expedition 41 crew aboard the International Space Station. The spacewalkers worked outside the space station's Quest airlock for 6 hours and 13 minutes, relocating a failed cooling pump to external stowage and installing gear that provides back up power to external robotics equipment. Flight Engineer Barry Wilmore of NASA operated the Canadian robotic arm, maneuvered Gerst during the course of the spacewalk and served as the spacewalk coordinator. A second U.S. spacewalk is set for Oct. 15. Wilmore will don a U.S. spacesuit and follow Wiseman outside the Quest airlock for a 6-1/2 hour excursion. Gerst will serve as the spacewalk choreographer. The goal of the excursion is to replace a failed voltage regulator component on the starboard truss of the station. They will also move external camera equipment in advance of a major reconfiguration of station modules next year for the arrival of new docking adapters for commercial crew vehicles. Image Credit: NASA/ESA/Alexander Gerst via NASA http://ift.tt/1sePzrB

From the Temple of the Sun to the Temple of the Moon



What connects the Sun to the Moon? Many answers have been given throughout history, but in the case of today's featured image, it appears to be the plane of our Milky Way Galaxy. The 16-image panorama was taken in Capitol Reef National Park, Utah, USA where two sandstone monoliths -- the Temple of the Moon on the right and the Temple of the Sun on the left -- rise dramatically from the desert. Each natural monument stands about 100 meters tall and survives from the Jurassic period 160 million years ago. Even older are many of the stars and nebulas that dot the celestial background, including the Andromeda Galaxy. Tomorrow the Earth will connect the Sun to the Moon by way of its shadow: a total lunar eclipse will be visible from many locations around the globe. via NASA http://ift.tt/1vKRfYF

2014/10/07

Space Station Detector Finds Unexplained Positron Excess



Where did all these high energy positrons come from? The Alpha Magnetic Spectrometer (AMS-02) onboard the International Space Station (ISS) has been meticulously recording how often it is struck by both high energy electrons and positrons since 2011. After accumulating years of data, it has now become clear that there are significantly more positrons than expected at the highest energies detected. The excess may have a very exciting and profound origin -- the annihilation of distant but previously undetected dark matter particles. However, it is also possible that astronomical sources such as pulsars are creating the unexplained discrepancy. The topic remains a very active area of research. Pictured here, the AMS is visible on the ISS just after being installed, with a US Space Shuttle docked on the far right, a Russian Soyuz capsule docked on the far left, and the blue Earth that houses all nations visible across the background. via NASA http://ift.tt/1yGDlwz

2014/10/06

Launch Abort System Installed for Orion Flight Test



The launch abort system for the Orion Flight Test is lowered by crane for installation on the Orion spacecraft inside the Launch Abort System Facility, or LASF, at NASA's Kennedy Space Center in Florida. The completed crew and service modules will be tested and verified together with the launch abort system. Orion will remain inside the LASF until mid-November, when the United Launch Alliance Delta IV Heavy rocket is ready for integration with the spacecraft. Orion is the exploration spacecraft designed to carry astronauts to destinations not yet explored by humans, including an asteroid and Mars. It will have emergency abort capability, sustain the crew during space travel and provide safe re-entry from deep space return velocities. The first unpiloted test flight of the Orion is scheduled to launch in December atop the Delta IV Heavy rocket from Cape Canaveral Air Force Station in Florida to an altitude of 3,600 miles above the Earth's surface. The two-orbit, four-hour flight test will help engineers evaluate the systems critical to crew safety including the heat shield, parachute system and launch abort system. Image Credit: NASA/Cory Huston via NASA http://ift.tt/Z9buVl

2014/10/05

Mars, Antares, Moon, and Saturn



Mars, Antares, Moon, and Saturn are the brightest celestial beacons in this serene sky. The Sun's golden light is still scattered along the southwestern horizon though, captured after sunset on September 28. The evening gathering of wandering planets and Moon along with the bright star viewed as an equal to Mars and the Scorpion's Heart was enjoyed around planet Earth. But from the photographer's perspective looking across the calm waters of Lake Balaton, Hungary, they were joined by a more terrestrial sailboat mast light. Mast light, bright star, planets and Moon are all posing near the plane of the ecliptic. via NASA http://ift.tt/1vo1AcN

2014/10/04

Aurora and Milky Way in a Little Sky



Stepping stones seem to lead to the Milky Way as it stretches across this little sky. Of course, the scene is really the northern hemisphere's autumnal equinox night. Water and sky are inverted by a top to bottom, around the horizon stereographic projection centered on the zenith above Lake Storsjön in Jämtland, Sweden. In the north the Milky Way arcs from east to west overhead as fall begins, but the season is also a good time for viewing aurora. Geomagnetic storms increase in frequency near the equinox and produce remarkable displays of northern lights at high latitudes, like the eerie greenish glow reflected in this watery cosmos. via NASA http://ift.tt/1rCnE5K

2014/10/03

The Bubble Nebula



Blown by the wind from a massive star, this interstellar apparition has a surprisingly familiar shape. Cataloged as NGC 7635, it is also known simply as The Bubble Nebula. Although it looks delicate, the 10 light-year diameter bubble offers evidence of violent processes at work. Below and left of the Bubble's center is a hot, O star, several hundred thousand times more luminous and around 45 times more massive than the Sun. A fierce stellar wind and intense radiation from that star has blasted out the structure of glowing gas against denser material in a surrounding molecular cloud. The intriguing Bubble Nebula and associated cloud complex lie a mere 11,000 light-years away toward the boastful constellation Cassiopeia. This tantalizing view of the cosmic bubble is composed from narrowband image data, recording emission from the region's ionized hydrogen and oxygen atoms. To create the three color image, hydrogen and oxygen emission were used for red and blue and combined to create the green channel. via NASA http://ift.tt/1rxAphS

2014/10/02

James Webb Space Telescope Sunshield Test Unfolds Seamlessly



A major test of the sunshield for NASA’s James Webb Space Telescope was conducted recently by Northrop Grumman in Redondo Beach, California. For the first time, the five sunshield test layers were unfolded and separated; unveiling important insights for the engineers and technicians as to how the deployment will take place when the telescope launches into space. “These tests are critical and allow us to see how our modeling works and learn about any modifications we may need to make in our design as we move into sunshield flight production,” said Jim Flynn, Webb sunshield manager. The three-day test took place in July, taking seven engineers and six technicians about 20 hours to complete. On orbit, the sunshield will take several days to unfold. “Tests on the ground are a little bit tricky because we have to account for gravity,” says Flynn. “Webb won’t face those same challenges in space. To overcome challenges on the ground, our technicians came up with the idea to rest the layers on a structure of metal beams covered by plastic.” The tennis court-sized sunshield, which is the largest part of the observatory, will be folded up around the Webb telescope’s mirrors and instruments during launch. As the telescope travels to its orbit one million miles from Earth, it will receive a command to unfold and separate the sunshield's five layers into their precisely stacked arrangement with its kite-like shape. The sunshield separates the observatory into a warm, sun-facing side (reaching temperatures close to 400 degrees Farenheit), and a cold side (185 degrees below zero) where the sunlight is blocked from interfering with the sensitive telescope instruments. It provides the instruments with an effective sun protection factor, or SPF, of one million. The sunshield’s membrane layers, each as thin as a human hair, are made of Kapton, a tough, high-performance plastic coated with a reflective metal. On orbit, the observatory will be pointed so that the sun, Earth and moon are always on one side, with the sunshield acting as an umbrella to shade the telescope mirrors and instruments from the warmer spacecraft electronics and the sun. Northrop Grumman subcontractor NeXolve is currently manufacturing the flight sunshield layers at their facilities in Huntsville, Ala. The five flight layers will be delivered to Northrop Grumman in 2016, when extensive testing will continue, followed by integration with the entire observatory. Image Credit: Northrop Grumman/Alex Evers via NASA http://ift.tt/1oEmDUN

The Butterfly Nebula from Hubble



The bright clusters and nebulae of planet Earth's night sky are often named for flowers or insects. Though its wingspan covers over 3 light-years, NGC 6302 is no exception. With an estimated surface temperature of about 250,000 degrees C, the dying central star of this particular planetary nebula has become exceptionally hot, shining brightly in ultraviolet light but hidden from direct view by a dense torus of dust. This sharp close-up of the dying star's nebula was recorded in 2009 by the Hubble Space Telescope's Wide Field Camera 3, and is presented here in reprocessed colors. Cutting across a bright cavity of ionized gas, the dust torus surrounding the central star is near the center of this view, almost edge-on to the line-of-sight. Molecular hydrogen has been detected in the hot star's dusty cosmic shroud. NGC 6302 lies about 4,000 light-years away in the arachnologically correct constellation of the Scorpion (Scorpius). via NASA http://ift.tt/1rFxe6E

2014/10/01

A Full Circle Rainbow over Australia



Have you ever seen an entire rainbow? From the ground, typically, only the top portion of a rainbow is visible because directions toward the ground have fewer raindrops. From the air, though, the entire 360 degree circle of a rainbow is more commonly visible. Pictured here, a full circle rainbow was captured over Cottesloe Beach near Perth, Australia last year by a helicopter flying between a setting sun and a downpour. An observer-dependent phenomenon primarily caused by the internal reflection of sunlight by raindrops, the 84-degree diameter rainbow followed the helicopter, intact, for about 5 kilometers. As a bonus, a second rainbow that was more faint and color-reversed was visible outside the first. via NASA http://ift.tt/YK2ZQn