Space

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Short Shadow



The projection of Saturn's shadow on the rings grows shorter as Saturn's season advances toward northern summer, thanks to the planet's permanent tilt as it orbits the sun. This will continue until Saturn's solstice in May 2017. At that point in time, the shadow will extend only as far as the innermost A ring, leaving the middle and outer A ring completely free of the planet's shadow.

Over the course of NASA's Cassini mission, the shadow of Saturn first lengthened steadily until equinox in August 2009. Since then, the shadow has been shrinking. This view looks toward the sunlit side of the rings from about 10 degrees above the ring plane.

The image was taken in visible light with the Cassini spacecraft wide-angle camera on Feb. 3, 2017. The view was acquired at a distance of approximately 760,000 miles (1.2 million kilometers) from Saturn.

SueSueDio

@cee134 I just wanted to say thanks for taking the time to post all of these pictures and info - it's very interesting!

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ECHO 100' Satellite Inflation Tests

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Portrait of a Galaxy Life



Evidence from NASA Galaxy Evolution Explorer supports the long-held notion that many galaxies begin life as smaller spirals before transforming into larger, elliptical-shaped galaxies.

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Not all Martian sand dunes are located in craters. This image from NASA 2001 Mars Odyssey spacecraft shows dunes located on the plains of Terra Sirenum.

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NASA's Dawn spacecraft successfully observed Ceres at opposition on April 29, 2017, taking images from a position exactly between the sun and Ceres' surface. Ceres is the largest object in the asteroid belt that lies between the orbits of Mars and Jupiter.

Mission specialists had carefully maneuvered Dawn into a special orbit so that the spacecraft could view Occator Crater, which contains the brightest area of Ceres, from this new perspective. A movie shows these opposition images, with contrast enhanced to highlight brightness differences.

The bright spots of Occator stand out particularly well on an otherwise relatively bland surface. Dawn took these images from an altitude of about 12,000 miles (20,000 kilometers). Based on data from ground-based telescopes and spacecraft that have previously viewed planetary bodies at opposition, scientists predicted that Ceres would appear brighter from this opposition configuration. This increase in brightness, or "surge," relates the size of the grains of material on the surface, as well as how porous those materials are.

The science motivation for performing these observations is further explained in the March 2017 issue of the Dawn Journal blog.

A movie can be viewed at https://photojournal.jpl.nasa.gov/catalog/PIA21405

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Canada's robotic arm, the Canadarm2, which is part of the Space Station Remote Manipulator System, is pictured with the Earth's limb in the background during a daytime orbital pass.

A pair of CubeSats, with the Earth’s limb in the background, is seen moments after being ejected from a small satellite deployer outside of the space station’s Kibo lab module.

The Moon, the Earth's limb and thin blue atmosphere are seen in this photograph taken by an Expedition 51 crew member.

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Juno Scientists Prepare for Fifth Science Pass of Jupiter

https://www.nasa.gov/feature/jpl/juno-scientists-prepare-for-fifth-science-pass-of-jupiter

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NASA astronaut Peggy Whitson is seen during the 200th spacewalk in support of the International Space Station.

Expedition 51 Commander Peggy Whitson and Flight Engineer Jack Fischer of NASA successfully replaced a large avionics box that supplies electricity and data connections to the science experiments.

The astronauts also completed additional tasks to install a connector that will route data to the Alpha Magnetic Spectrometer, repair insulation at the connecting point of the Japanese robotic arm, and install a protective shield on the Pressurized Mating Adapter-3.

This adapter will host a new international docking port for the arrival of commercial crew spacecraft.

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This enhanced color image of Ceres' surface was made from data obtained on April 29, 2017, when NASA's Dawn spacecraft was exactly between the sun and Ceres.

Dawn's framing cameras took images of Ceres with a clear filter as well as five different color filters. Images combining these different color filter perspectives reveal fine details of Ceres' surface.

For example, they emphasize the distinct compositions and textures of the material ejected from craters. The brightest region on Ceres, called Cerealia Facula, is highlighted in Occator Crater in the center of this image. Vinalia Faculae, the set of secondary bright spots in the same crater, are located to the right of Cerealia Facula. One of the darkest regions on Ceres is next to Occator, and represents ejected material from the impact that formed the crater.

The ejected material forms a large arc that extends over several hundred kilometers, below the center of Ceres in this image. That material's distribution is partly determined by Ceres' rotation. Other craters also show a mixture of bright and dark regions. While the bright areas are generally identified as salt-rich material excavated from Ceres' crust, the origin of the dark material remains to be explained. It may have been excavated from a different layer within Ceres' subsurface than the rest of the ejecta blanket.

Scientists will continue analyzing the color data to look for clues about the nature of the different materials on Ceres. The blueish color is generally found in association with young craters. Scientists believe the color relates to processes that occur when an impact ejects and redistributes material on the surface. The continuous bombardment of Ceres' surface by micrometeorites alters the texture of the exposed material, leading to its reddening.

This image was taken altitude of about 12,000 miles (20,000 kilometers).

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• Several bright bands of plasma connect from one active region to another, even though they are tens of thousands of miles away from each other (May 17-18, 2017).
  
• Active regions are, by their nature, strong magnetic areas with north and south poles.
  
• The plasma consists of charged particles that stream along the magnetic field lines between these two regions.
  
• These connecting lines are clearly visible in this wavelength of extreme ultraviolet light.
  
• Other loops and strands of bright plasma can be seen rising up and out of smaller active regions as well.

The video covers about one day's worth of activity. Movies are available at https://photojournal.jpl.nasa.gov/catalog/PIA21638

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Light from a Flickering Star

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White Dwarf Stars



Peering deep inside a cluster of several hundred thousand stars, NASA Hubble Space Telescope has uncovered the oldest burned-out stars in our Milky Way Galaxy, giving astronomers a fresh reading on the age of the universe.

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Jupiter



Waves of clouds at 37.8 degrees latitude dominate this three-dimensional Jovian cloudscape, courtesy of NASA's Juno spacecraft.

JunoCam obtained this enhanced-color picture on May 19, 2017, at 5:50 UTC from an altitude of 5,500 miles (8,900 kilometers).

Details as small as 4 miles (6 kilometers) across can be identified in this image. The small bright high clouds are about 16 miles (25 kilometers) across and in some areas appear to form "squall lines" (a narrow band of high winds and storms associated with a cold front). On Jupiter, clouds this high are almost certainly composed of water and/or ammonia ice.

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Southern Storms



This image shows Jupiter's south pole, as seen by NASA's Juno spacecraft from an altitude of 32,000 miles (52,000 kilometers).

The oval features are cyclones, up to 600 miles (1,000 kilometers) in diameter.

Multiple images taken with the JunoCam instrument on three separate orbits were combined to show all areas in daylight, enhanced color, and stereographic projection.

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Jupiter's Southern Lights



The complexity and richness of Jupiter's "southern lights" (also known as auroras) are on display in this animation of false-color maps from NASA's Juno spacecraft.

Auroras result when energetic electrons from the magnetosphere crash into the molecular hydrogen in the Jovian upper atmosphere.

The data for this animation were obtained by Juno's Ultraviolet Spectrograph.

The images are centered on the south pole and extend to latitudes of 50 degrees south. Each frame of the animation includes data from 30 consecutive Juno spins (about 15 minutes), just after the spacecraft's fifth close approach to Jupiter on February 2, 2017.

The eight frames of the animation cover the period from 13:40 to 15:40 UTC at Juno. During that time, the spacecraft was receding from 35,000 miles to 153,900 miles (56,300 kilometers to 247,600 kilometers) above the aurora; this large change in distance accounts for the increasing fuzziness of the features.

Jupiter's prime meridian is toward the bottom, and longitudes increase counterclockwise from there.

The sun was located near the bottom at the start of the animation, but was off to the right by the end of the two-hour period.

The red coloring of some of the features indicates that those emissions came from deeper in Jupiter's atmosphere; green and white indicate emissions from higher up in the atmosphere.

Animations are available at https://photojournal.jpl.nasa.gov/catalog/PIA21643

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Jupiter Ring, With Orion




As NASA's Juno spacecraft flew through the narrow gap between Jupiter's radiation belts and the planet during its first science flyby, Perijove 1, on August 27, 2016, the Stellar Reference Unit (SRU-1) star camera collected the first image of Jupiter's ring taken from the inside looking out.

The bright bands in the center of the image are the main ring of Jupiter's ring system. While taking the ring image, the SRU was viewing the constellation Orion.

The bright star above the main ring is Betelgeuse, and Orion's belt can be seen in the lower right.

Juno's Radiation Monitoring Investigation actively retrieves and analyzes the noise signatures from penetrating radiation in the images of the spacecraft's star cameras and science instruments at Jupiter.

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A South Polar Pit or an Impact Crater?




This observation from NASA's Mars Reconnaissance Orbiter show it is late summer in the Southern hemisphere, so the Sun is low in the sky and subtle topography is accentuated in orbital images.

We see many shallow pits in the bright residual cap of carbon dioxide ice (also called "Swiss cheese terrain"). There is also a deeper, circular formation that penetrates through the ice and dust.

This might be an impact crater or it could be a collapse pit.

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Halos in Martian Sandstone



Pale zones called "halos" border bedrock fractures visible in this 2015 image from NASA's Curiosity Mars rover which has been darkened (a previously released image can be seen at PIA20268).

Measurements overlaid on the image offer a sense of scale for the size of these fractures. The rover team determined that the halos are rich in silica, a clue to the duration of wet environmental conditions long ago.

The location is on the lower slope of Mars' Mount Sharp. Curiosity's Navigation Camera (Navcam) acquired the component images of this mosaic on Aug. 23, 2015, during the 1.083rd Martian day, or sol, of the mission.

The location is along the rover's path between "Marias Pass" and "Bridger Basin." In this region, the rover has found fracture zones to be associated with rock compositions enriched in silica, relative to surrounding bedrock.

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(May 26, 2017) --- Three CubeSats, with Earth’s limb and thin atmosphere in the background, is seen shortly after being ejected from a small satellite deployer outside of the Japanese Kibo laboratory module.

The trio are part of a subset CubeSats released during the week to monitor different gaseous molecules and electrical properties of the Earth's thermosphere to better understand space weather and its long term trends.