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

NASA astronaut Reid Wiseman checks his spacesuit in preparation for the first Expedition 41 spacewalk in this image, posted to social media by European Space Agency astronaut Alexander Gerst. Wiseman and Gerst will work outside the International Space Station for about 6-1/2 hours Tuesday, Oct. 7. They set their spacesuits to internal battery power at 8:30 a.m. EDT Tuesday morning, signifying the official start of the spacewalk. The spacewalkers will move a failed cooling pump from temporary to long-term storage on the station’s truss. They also will install a new relay system that will provide backup power options to the mobile transporter, which moves the large robotic arm around the outside of the space station.

> Wiseman and Gerst Conduct First Spacewalk of Expedition 41

Image Credit: NASA/ESA/Alexander Gerst via NASA http://ift.tt/1oN3KiG

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

The four images that make up this montage of comet 67P/Churyumov–Gerasimenko were taken on Sept. 26, 2014 by the European Space Agency’s Rosetta spacecraft. At the time, Rosetta was about 16 miles (26 kilometers), from the center of the comet.

In the montage, a region of jet activity can be seen at the neck of the comet. These jets, originating from several discrete locations, are a product of ices sublimating and gases escaping from inside the nucleus.  

The overlapping and slightly dissimilar angles of the four images that compose the montage are a result of the combined effect of the comet rotating between the first and last images taken in the sequence (about 10 degrees over 20 minutes), and the spacecraft movement during that same time.

Launched in March 2004, Rosetta was reactivated in January 2014 after a record 957 days in hibernation. Composed of an orbiter and lander, Rosetta’s objectives since arriving at comet 67P/Churyumov-Gerasimenko earlier this month are to study the celestial object up close in unprecedented detail, prepare for landing a probe on the comet’s nucleus in November, and after the landing track the comet’s changes through 2015, as it sweeps past the sun.

Comets are time capsules containing primitive material left over from the epoch when the sun and its planets formed. Rosetta’s lander will obtain the first images taken from a comet’s surface and will provide comprehensive analysis of the comet’s possible primordial composition by drilling into the surface. Rosetta also will be the first spacecraft to witness at close proximity how a comet changes as it is subjected to the increasing intensity of the sun’s radiation. Observations will help scientists learn more about the origin and evolution of our solar system and the role comets may have played in seeding Earth with water, and perhaps even life.

Rosetta is an ESA mission with contributions from its member states and NASA. Rosetta’s Philae lander is provided by a consortium led by the German Aerospace Center, Cologne; Max Planck Institute for Solar System Research, Gottingen; National Center of Space Studies of France (CNES), Paris; and the Italian Space Agency, Rome. NASA’s Jet Propulsion Laboratory in Pasadena, California, a division of the California Institute of Technology, manages the U.S. participation in the Rosetta mission for NASA’s Science Mission Directorate in Washington.

For more information on the U.S. instruments aboard Rosetta, visit:

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More information about Rosetta is available at:

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Image Credit: ESA/Rosetta/NAVCAM via NASA http://ift.tt/1tniSV2

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

NASA astronaut Reid Wiseman captured this image from the International Space Station and posted it to social media on Sept. 28, 2014, writing, “The Milky Way steals the show from Sahara sands that make the Earth glow orange.”

Aboard the space station, the six-person Expedition 41 crew is currently preparing for two spacewalks set for Oct. 7 and 15. During the first six-and-a-half-hour spacewalk, slated to begin on Oct. 7 around 8:10 a.m. EDT, Wiseman and European Space Agency astronaut Alexander Gerst will transfer a previously uninstalled pump module from its temporary stowage location to the External Stowage Platform-2. The two spacewalkers also will install the Mobile Transporter Relay Assembly that adds the capability to provide “keep-alive” power to the system that moves the station’s robotic arm between worksites. NASA astronaut Barry Wilmore will join Wiseman for the second Expedition 41 spacewalk on Oct. 15.

Image Credit: NASA/Reid Wiseman via NASA http://ift.tt/1xBGsV8

A few days after autumn showed up on the calendar in the Northern Hemisphere, it showed up on the landscape of North America. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite captured this view of fall colors around the Great Lakes on Sept. 26, 2014.

The changing of leaf color in temperate forests involves several causes and reactions, but the dominant factors are sunlight and heat. Since temperatures tend to drop sooner and sunlight fades faster at higher latitudes, the progression of fall color changes tends to move from north to south across North America from mid-September through mid-November.

In late summer and autumn, tree and plant leaves produce less chlorophyll, the green pigment that harvests sunlight for plants to convert water and carbon dioxide into sugars. The subsidence of chlorophyll allows other chemical compounds in the leaves—particularly carotenoids and flavonoids—to emerge from the green shadow of summer. These compounds do not decay as fast as chlorophyll, so they shine through in yellows, oranges, and reds as the green fades. Another set of chemicals, anthocyanins, are associated with the storage of sugars and give the leaves of some species deep purple and red hues.

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Image Credit: Jeff Schmaltz at NASA GSFC. Caption by Mike Carlowicz via NASA http://ift.tt/10jQcFw