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

Engineers took another step forward in preparations for the first test flight of NASA’s new Orion spacecraft in December. At the United Launch Alliance (ULA) Horizontal Integration Facility (HIF), at Cape Canaveral Air Force Station, Florida, the three primary core elements of the ULA Delta IV Heavy rocket recently were integrated, forming the first stage of the launch vehicle that will send Orion far from Earth to allow NASA to evaluate the spacecraft’s performance in space.

The three common booster cores are 134 feet in length and 17 feet in diameter. Each has an RS-68 engine that uses liquid hydrogen and liquid oxygen propellant producing 656,000 pounds of thrust. All totaled, the three Delta IV boosters collectively generate 1.96 million pounds of thrust.

The upcoming flight test will use the Delta IV Heavy to launch the Orion and send it 3,600 miles in altitude beyond the Earth’s surface. During the two-orbit, four-hour mission, engineers will evaluate the systems critical to crew safety, the launch abort system, the heat shield and the parachute system. The data gathered during the mission will influence design decisions and validate existing computer models. The flight also will reduce overall mission risks and costs for later Orion flights.

> Delta IV Booster Integration Another Step Toward First Orion Flight

Image Credit: NASA/Ben Smegelsky via NASA http://ift.tt/1xu3GMN

The Soyuz TMA-14M rocket is launched with Expedition 41 Soyuz Commander Alexander Samokutyaev of the Russian Federal Space Agency (Roscosmos) Flight Engineer Elena Serova of Roscosmos, and Flight Engineer Barry Wilmore of NASA, Friday, Sept. 26, 2014 at the Baikonur Cosmodrome in Kazakhstan. Samokutyaev, Serova, and Wilmore will spend the next five and a half months aboard the International Space Station. Serova will become the fourth Russian woman to fly in space and the first Russian woman to live and work on the station.

Image Credit: NASA/Joel Kowsky via NASA http://ift.tt/1qzGjsr

On a July night this summer, a 5,200-pound balloon gondola hangs from a crane and moves toward the open doors of a building at the Johns Hopkins University Applied Physics Lab in Laurel, Md. The telescopes and instruments carried by the gondola, which are part of NASA’s Balloon Observation Platform for Planetary Science (BOPPS), are calibrated by taking a long look at the stars and other objects in the sky.

This photo was created from 100 separate 30-second-exposure photos, composited together to make the star trail that “spins” around Polaris, the North Star.

BOPPS is a high-altitude, stratospheric balloon mission, which will spend up to 24 hours aloft to study a number of objects in our solar system, including an Oort cloud comet. Two comets that may be visible during the flight include Pan STARRS and Siding Spring, which will pass very close to Mars on Oct. 19. The mission may also survey a potential array of other targets including asteroids Ceres and Vesta, Earth’s moon, and Neptune and Uranus. BOPPS is scheduled to launch on Sept. 25 from the NASA Columbia Scientific Balloon Research Facility in Fort Sumner, New Mexico.

Learn more about the BOPPS mission:

> News Release

Image Credit: NASA/JHUAPL via NASA http://ift.tt/YcHrM2

On Sept. 19, 2014, the Operational Land Imager (OLI) on the Landsat 8 satellite captured these images of the King fire in Eldorado National Forest. In the false-color image, burned forest appears red; unaffected forests are green; cleared forest is beige; and smoke is blue. As of Sept. 23, the blaze had charred 36,320 hectares (89,571 acres).

> More information and annotated images
> Additional NASA resources: Fire and Smoke

Image Credit: NASA Earth Observatory image by Jesse Allen, using Landsat data from the U.S. Geological Survey
Caption: Adam Voiland via NASA http://ift.tt/ZLG9J3

The sun rises as the Soyuz TMA-14M spacecraft is rolled out by train to the launch pad at the Baikonur Cosmodrome, Kazakhstan, Sept. 23, 2014. Launch of the Soyuz rocket is scheduled for Sept. 25 at 4:25 p.m. EDT (Sept. 26 at 2:25 a.m. Kazakh time) and will carry Expedition 41 Soyuz Commander Alexander Samokutyaev of the Russian Federal Space Agency (Roscosmos), Flight Engineer Barry Wilmore of NASA, and Flight Engineer Elena Serova of Roscosmos into orbit to begin their five and a half month mission on the International Space Station.

Image Credit: NASA/Joel Kowsky via NASA http://ift.tt/1vclasP

The Cassini spacecraft captures a rare family photo of three of Saturn’s moons that couldn’t be more different from each other! As the largest of the three, Tethys (image center) is round and has a variety of terrains across its surface. Meanwhile, Hyperion (to the upper-left of Tethys) is the “wild one” with a chaotic spin and Prometheus (lower-left) is a tiny moon that busies itself sculpting the F ring.

To learn more about the surface of Tethys (660 miles, or 1,062 kilometers across), see PIA17164. More on the chaotic spin of Hyperion (168 miles, or 270 kilometers across) can be found at PIA07683. And discover more about the role of Prometheus (53 miles, or 86 kilometers across) in shaping the F ring in PIA12786.

This view looks toward the sunlit side of the rings from about 1 degree above the ringplane. 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 1.2 million miles (1.9 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/Z9QWgf