ISS040-E-090540 (9 Aug. 2014) — One of the Expedition 40 crew members aboard the International Space Station photographed this nighttime image showing city lights in at least half a dozen southern states from some 225 miles above the home planet. Lights from areas in the Gulf Coast states of Texas, Louisiana, Mississippi and Alabama, as well as some of the states that border them on the north, are visible.

Image Credit: NASA via NASA http://ift.tt/1oVu5i3

New data from NASA’s Chandra X-ray Observatory has provided stringent constraints on the environment around one of the closest supernovas discovered in decades. The Chandra results provide insight into possible cause of the explosion, as described in our press release.
 
On January 21, 2014, astronomers witnessed a supernova soon after it exploded in the Messier 82, or M82, galaxy. Telescopes across the globe and in space turned their attention to study this newly exploded star, including Chandra.  Astronomers determined that this supernova, dubbed SN 2014J, belongs to a class of explosions called “Type Ia” supernovas. These supernovas are used as cosmic distance-markers and played a key role in the discovery of the Universe’s accelerated expansion, which has been attributed to the effects of dark energy.  Scientists think that all Type Ia supernovas involve the detonation of a white dwarf. One important question is whether the fuse on the explosion is lit when the white dwarf pulls too much material from a companion star like the Sun, or when two white dwarf stars merge. 
 
This image contains Chandra data, where low, medium, and high-energy X-rays are red, green, and blue respectively. The boxes in the bottom of the image show close-up views of the region around the supernova in data taken prior to the explosion (left), as well as data gathered on February 3, 2014, after the supernova went off (right).  The lack  of the detection of X-rays detected by Chandra is an important clue for astronomers looking for the exact mechanism of how this star exploded.
 
The non-detection of X-rays reveals that the region around the site of the supernova explosion is relatively devoid of material. This finding is a critical clue to the origin of the explosion. Astronomers expect that if a white dwarf exploded because it had been steadily collecting matter from a companion star prior to exploding, the mass transfer process would not be 100% efficient, and the white dwarf would be immersed in a cloud of gas.
 
If a significant amount of material were surrounding the doomed star, the blast wave generated by the supernova would have struck it by the time of the Chandra observation, producing a bright X-ray source. Since they do not detect any X-rays, the researchers determined that the region around SN 2014J is exceptionally clean.
 
A viable candidate for the cause of SN 2014J must explain the relatively gas-free environment around the star prior to the explosion.  One possibility is the merger of two white dwarf stars, in which case there might have been little mass transfer and pollution of the environment before the explosion. Another is that several smaller eruptions on the surface of the white dwarf cleared the region prior to the supernova.  Further observations a few hundred days after the explosion could shed light on the amount of gas in a larger volume, and help decide between these and other scenarios.
 
A paper describing these results was published in the July 20 issue of The Astrophysical Journal and is available online. The first author is Raffaella Margutti from the Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, MA, and the co-authors are Jerod Parrent (CfA), Atish Kamble (CfA), Alicia Soderberg (CfA), Ryan Foley (University of Illinois at Urbana-Champaign), Dan Milisavljevic (CfA), Maria Drout (CfA), and Robert Kirshner (CfA).
Image Credit: NASA/CXC/SAO/R.Margutti et al
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The center section of the “pathfinder” (test) backplane of NASA’s James Webb Space Telescope arrived at the Goddard Space Flight Center in July 2014, to be part of a simulation of putting together vital parts of the telescope. In this photograph, the backplane is hoisted into place in the assembly stand in NASA Goddard’s giant cleanroom, where over the next several months engineers and scientists will install two spare primary mirror segments and a spare secondary mirror. By installing the mirrors on the replica, technicians are able to practice this delicate procedure for when the actual flight backplane arrives. Installation of the mirrors on the backplane requires precision, so practice is important.
> James Webb Space Telescope “Pathfinder” Backplane’s Path to NASA
Image Credit: NASA/Chris Gunn via NASA http://ift.tt/1l2V77h

ISS040-E-088856 (5 Aug. 2014) — NASA astronaut Reid Wiseman, Expedition 40 flight engineer, installs Capillary Channel Flow (CCF) experiment hardware in the Microgravity Science Glovebox (MSG) located in the Destiny laboratory of the International Space Station. CCF is a versatile experiment for studying a critical variety of inertial-capillary dominated flows key to spacecraft systems that cannot be studied on the ground.
Capillary flow is the natural wicking of fluid between narrow channels in the opposite direction of gravity. Tree roots are one example of a capillary system, drawing water up from the soil. By increasing understanding of capillary flow in the absence of gravity, the Capillary Channel Flow (CCF) experiment helps scientists find new ways to move liquids in space. Capillary systems do not require pumps or moving parts, which reduces their cost, weight and complexity.
Image Credit: NASA via NASA http://ift.tt/1untpor

A perigee full moon or “supermoon” is seen, Sunday, Aug. 10, 2014, in Washington. A supermoon occurs when the moon’s orbit is closest (perigee) to Earth at the same time it is full.
Image Credit: NASA/Bill Ingalls via NASA http://ift.tt/1sPQ3mo

Divers retrieve the test vehicle for NASA’s Low-Density Supersonic Decelerator off the coast of the U.S. Navy’s Pacific Missile Range Facility in Kauai, Hawaii. On June 28, 2014, the vehicle was lifted to near-space with the help of a balloon and rocket in order to test new Mars landing technologies. The divers, from the U.S. Navy’s Explosive Ordnance Disposal team, retrieved the vehicle hours after the successful test.
NASA’s Space Technology Mission Directorate funds the LDSD mission, a cooperative effort led by NASA’s Jet Propulsion Laboratory in Pasadena, California. NASA’s Technology Demonstration Mission program manages LDSD at NASA’s Marshall Space Flight Center in Huntsville, Alabama. NASA’s Wallops Flight Facility in Wallops Island, Virginia, coordinated support with the Pacific Missile Range Facility, provided the core electrical systems for the test vehicle, and coordinated the balloon and recovery services for the LDSD test.
For more information about the LDSD space technology demonstration mission: http://go.usa.gov/kzZQz.
Image Credit: NASA/JPL-Caltech via NASA http://ift.tt/1ssIjpl