"During this, our tenth holiday season at Saturn, we hope that these images from Cassini remind everyone the world over of the significance of our discoveries in exploring such a remote and beautiful planetary system," said Carolyn Porco, Cassini imaging team leader, based at the Space Science Institute, Boulder, Colo. "Happy holidays from all of us on Cassini."

Two views of Enceladus are included in the package and highlight the many fissures, fractures and ridges that decorate the icy moon's surface. Enceladus is a white, glittering snowball of a moon, now famous for the nearly 100 geysers that are spread across its south polar region and spout tiny icy particles into space. Most of these particles fall back to the surface as snow. Some small fraction escapes the gravity of Enceladus and makes its way into orbit around Saturn, forming the planet's extensive and diffuse E ring. Because scientists believe these geysers are directly connected to a subsurface, salty, organic-rich, liquid-water reservoir, Enceladus is home to one of the most accessible extraterrestrial habitable zones in the solar system.

Packaged along with Saturn and Enceladus is a group of natural-color images of Saturn's largest moon, Titan, highlighting two of Titan's most outstanding features. Peering through the moon's hazy, orange atmosphere, the Cassini narrow-angle camera spots dark, splotchy features in the polar regions of the moon. These features are the lakes and seas of liquid methane and ethane for which the moon is renowned. Titan is the only other place in the solar system that we know has stable liquids on its surface, though in Titan's case, the liquids are ethane and methane rather than water. At Titan's south pole, a swirling high-altitude vortex stands out distinctly against the darkness of the moon's un-illuminated atmosphere. Titan's hazy atmosphere and surface environment are believed to be similar in certain respects to the early atmosphere of Earth.

"Until Cassini arrived at Saturn, we didn't know about the hydrocarbon lakes of Titan, the active drama of Enceladus' jets, and the intricate patterns at Saturn's poles," said Linda Spilker, the Cassini project scientist at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "Spectacular images like these highlight that Cassini has given us the gift of knowledge, which we have been so excited to share with everyone." Launched in 1997, Cassini has explored the Saturn system for more than nine years. NASA plans to continue the mission through 2017, with the anticipation of much more groundbreaking science and imagery to come.

NASA's Deep Space Network, the world's largest and most powerful communications system for "talking to" spacecraft, will reach a milestone on Dec. 24: the 50th anniversary of its official creation.
Over the past 50 years, antennas of the Deep Space Network (DSN) have communicated with just about every mission that has gone to the moon or beyond. The historic communiqués include "That's one small step for man. One giant leap for mankind"; numerous encounters with the outer planets of our solar system; images taken by rovers exploring Mars; and the data confirming that NASA's Voyager spacecraft had finally entered interstellar space.

The Deep Space Network has been so critical to so many missions over the decades, the network's team members like to use the phrase "Don't leave Earth without us."
More information about the Deep Space Network is online at: http://www.jpl.nasa.gov/dsn50/
From the very beginning of NASA's space program, it was clear that a simple, direct way to communicate with missions in deep space would be needed. For example, what is the purpose of sending a spacecraft to Mars if we can't receive data, images and other vital information from that spacecraft?
What is now known as the Deep Space Network first existed as just a few small antennas called the Deep Space Instrumentation Facility. The facility was originally operated by the U.S. Army in the 1950s and then later moved over to the jurisdiction of the newly created National Aeronautics and Space Administration (NASA).

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Get to know the Deep Space Network (DSN)NASA's worldwide radio telescope array that communicates with spacecraft throughout the solar method.

As the World Turns: The DSN is Earth's only global spacecraft communication network

The Deep Space Network has facilities - at Goldstone, Calif.; near Madrid, Spain; and Canberra, Australia, all with multiple parabolic dish antennas, including dish each that is 230 feet (70 meters) across. Located about 120 degrees apart around Earth, the position of the complexes provides round-the-clock coverage of the solar method. (A telescope needs a direct line of sight to "speak" with a spacecraft.)

 Little Step: The DSN showed us the first moonwalk

That's little step for man. giant leap for mankind. The DSN received and relayed to the world the first TV images of astronaut Neil Armstrong setting foot on the surface of the moon in 1969.

Solar Method Ambassador: DSN relays first close-up views of other planets

The historic network enabled the world to see the first-ever picture of Mars, obtained by NASA's Mariner four spacecraft in 1965. Mariner ten returned images of Mercury's surface in 1974. NASA's twin Voyager spacecraft were the first to fly by Jupiter, Saturn, Neptune and Uranus, capturing the first close-up images of these planets, and some of their rings and moons. The DSN also relayed Voyager 1's portrait of Earth from 6 billion miles away, the iconic picture Carl Sagan called "The Pale Blue Dot," as well as the spacecraft's entry in to interstellar space.

Now Listen to This: The DSN speaks with 33 spacecraft

In the work of 1963, the DSN's first year of operation, it communicated with spacecraft. In 2013, space is a much busier place. The DSN is currently communicating with 33 spacecraft across the solar method. The DSN sends commands to spacecraft and receives telemetry, engineering and scientific knowledge.

Not NASA: The DSN relays knowledge on behalf of international space agencies

While the DSN tracks, sends commands to and receives knowledge from all NASA spacecraft beyond the moon, the network also supports spacecraft from the European Space Agency, Japanese Space Agency and Indian Space Agency.

There is Always Room for Science: The DSN is used for scientific observation

In addition to its crucial role in two-way spacecraft communication, DSN dishes make direct science observations. There is radar science, in which waves are bounced off objects such as passing asteroids to generate radar images; radio science, where changes in the steady radio link between a spacecraft and the DSN reveal the internal structure of another world; radio astronomy, which looks at naturally occurring radio sources such as pulsars and quasars; and geodetic measurements, which reveal changes in the crust of Earth by tracking how long it takes a radio signal from a quasar or other astronomical source to reach different telescopes.

A newly released image from NASA's Wide-Field Infrared Survey Explorer (WISE) shows a dying star, called the Helix nebula, surrounded by the tracks of asteroids. The nebula is far outside our solar system, while the asteroid tracks are inside our solar system.
Amazing Picture for WISE's Fourth Anniversary

The portrait, discovered by chance in a search for asteroids, comes at a time when the mission's team is celebrating its fourth launch anniversary -- and new lease on life. In August, NASA decided to bring WISE out of hibernation to search for more asteroids. The mission was rechristened NEOWISE, formerly the name of the asteroid-hunting portion of WISE. "I was recently looking for asteroids in images collected in 2010, and this picture jumped out at me," said Amy Mainzer, the NEOWISE principal investigator at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "I recognized the Helix nebula right away."
WISE launched into the morning skies above Vandenberg Air Force Base in central California on Dec. 14, 2009. By early 2011, it had finished scanning the entire sky twice in infrared light, snapping pictures of nearly one billion objects, including remote galaxies, stars and asteroids. Upon completing its main goals, WISE was put to sleep. Now, engineers are bringing the spacecraft out of slumber, as it cools back down to the chilly temperatures required for infrared observations. The spacecraft no longer has onboard coolant, but two of its infrared channels still work and can be used for asteroid hunting.
"WISE is the spacecraft that keeps on giving," said Ned Wright of UCLA, the principal investigator of WISE before it transitioned into NEOWISE.
In the Helix nebula image, infrared wavelengths of light have been assigned different colors, with longer wavelengths being red, and shorter, blue. The bluish-green and red materials are expelled remnants of what was once a star similar to our sun. As the star aged, it puffed up and its outer layers sloughed off. The burnt-out core of the star, called a white dwarf, is heating the expelled material, inducing it to glow with infrared light. Over time, the brilliant object, known as a planetary nebula, will fade away, leaving just the white dwarf.

The VeSpR (Venus Spectral Rocket) Experiment launched successfully from White Sand Missile Range.  VeSpR will study the present day escape of water from the atmosphere of Venus and relate it to the past abundance of water on Venus by measuring hydrogen (H) and the heavier, slower to escape, deuterated hydrogen (D) above 90 km on Venus. The use of a pre-dispersing prism to prevent long wavelengths from entering the spectrograph permits a long-aperture approach to echelle spectroscopy, and the chosen combination of imaging and dispersion scales provides high spectral resolution of emission line profiles with a several arc sec wide aperture for good sensitivity. For comparable spectral resolution the HST/STIS uses a 0.2 arc sec aperture, which provides 375 times less solid angle on the sky than a 3 x 5 arc sec region observed by the sounding rocket telescope.  Good data was obtained by both detectors with no obvious significant anomalies.  Preliminary reports indicate a successful mission.

Sounding Rocket to Peek at Atmosphere of Venus

The Mars Atmosphere and Volatile Evolution, or MAVEN, mission launched from Cape Canaveral Air Force Station in Florida on Nov. 18. Now, the Venus Spectral Rocket, VeSpR for short, is scheduled to lift off from White Sands, N.M., on Nov. 25.

"It is appropriate that these launch dates are close together, because both missions will study atmospheric loss," said Kelly Fast, the program scientist for MAVEN and the program officer for Planetary Astronomy at NASA Headquarters in Washington. "VeSpR will peek at Venus from above Earth's absorbing atmosphere, and MAVEN will journey to Mars to do a long-term study."

VeSpR is a two-stage system, combining a Terrier missile – originally built as a surface-to-air missile and later repurposed to support science missions – and a Black Brant model Mk1 sounding rocket with a telescope inside. Integration took place at NASA’s Wallops Flight Facility in Virginia.

The experiments will look at ultraviolet (UV) light that is being emitted from Venus' atmosphere, which can provide information about the history of the planet's water. Measurements like these cannot be done using Earth-based telescopes because our atmosphere absorbs most UV light before it reaches the ground.

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The Boeing Company of Houston, a NASA Commercial Crew Program (CCP) partner, recently performed wind tunnel testing of its CST-100 spacecraft and integrated launch vehicle, the United Launch Alliance (ULA) Atlas V rocket. The testing is part of NASA's Commercial Crew Integrated Capability (CCiCap) initiative, intended to make commercial human spaceflight services available for government and commercial customers. 

Boeing and ULA also worked together to test a newly developed component of the Atlas V's Centaur upper stage. Boeing now has completed two of eight performance milestones under CCiCap and is on track to have completed all 19 of its milestones around mid-2014.

"The Centaur has a long and storied past of launching the agency's most successful spacecraft to other worlds," said Ed Mango, NASA's CCP manager at the agency's Kennedy Space Center in Florida. "Because it has never been used for human spaceflight before, these tests are critical to ensuring a smooth and safe performance for the crew members who will be riding atop the human-rated Atlas V."

The wind tunnel testing, which began in March and wrapped up in May at NASA's Ames Research Center in Moffett Field, Calif., were the first interface tests of Boeing's spacecraft, launch vehicle adaptor and launch vehicle. A scale model of the integrated spacecraft and rocket was placed in Ames' 11-foot diameter transonic wind tunnel. The data gathered provides Boeing with critical information it needs to ensure its system is safe for launching crews to low-Earth orbit.  

The Centaur liquid oxygen-feed duct line was tested in March in Murrieta, Calif., to characterize how liquid oxygen moves from the stage's oxygen tank to its two engines where the propellant will be mixed with liquid hydrogen to create thrust. The Centaur, which takes over after the Atlas V first stage runs low on propellants, will push the spacecraft to its intended orbit. The Centaur has an extensive and successful history of delivering spacecraft to their destinations, including carrying NASA's Curiosity science rover to Mars. 

A new study of glaciers worldwide using observations from two NASA satellites has helped resolve differences in estimates of how fast glaciers are disappearing and contributing to sea level rise.

The new research found glaciers outside of the Greenland and Antarctic ice sheets, repositories of 1 percent of all land ice, lost an average of 571 trillion pounds (259 trillion kilograms) of mass every year during the six-year study period, making the oceans rise 0.03 inches (0.7 mm) per year. This is equal to about 30 percent of the total observed global sea level rise during the same period and matches the combined contribution to sea level from the Greenland and Antarctica ice sheets.

The study compares traditional ground measurements to satellite data from NASA's Ice, Cloud, and Land Elevation Satellite (ICESat) and Gravity Recovery and Climate Experiment (GRACE) missions to estimate ice loss for glaciers in all regions of the planet. The study period spans 2003 to 2009, the years when the two missions overlapped.

"For the first time, we have been able to very precisely constrain how much these glaciers as a whole are contributing to sea level rise," said Alex Gardner, Earth scientist at Clark University in Worcester, Mass., and lead author of the study. "These smaller ice bodies are currently losing about as much mass as the ice sheets."

NASA's Hubble Space Telescope has found the building blocks for Earth-sized planets in an unlikely place-- the atmospheres of a pair of burned-out stars called white dwarfs.

These dead stars are located 150 light-years from Earth in a relatively young star cluster, Hyades, in the constellation Taurus. The star cluster is only 625 million years old. The white dwarfs are being polluted by asteroid-like debris falling onto them.
NASA's Hubble Space Telescope Finds Dead Stars 'Polluted with Planet Debris

Hubble's Cosmic Origins Spectrograph observed silicon and only low levels of carbon in the white dwarfs' atmospheres. Silicon is a major ingredient of the rocky material that constitutes Earth and other solid planets in our solar system. Carbon, which helps determine properties and origin of planetary debris, generally is depleted or absent in rocky, Earth-like material.

"We have identified chemical evidence for the building blocks of rocky planets," said Jay Farihi of the University of Cambridge in England. He is lead author of a new study appearing in the Monthly Notices of the Royal Astronomical Society. "When these stars were born, they built planets, and there's a good chance they currently retain some of them. The material we are seeing is evidence of this. The debris is at least as rocky as the most primitive terrestrial bodies in our solar system."

This discovery suggests rocky planet assembly is common around stars, and it offers insight into what will happen in our own solar system when our sun burns out 5 billion years from now.

Farihi's research suggests asteroids less than 100 miles (160 kilometers)
wide probably were torn apart by the white dwarfs' strong gravitational forces. Asteroids are thought to consist of the same materials that form terrestrial planets, and seeing evidence of asteroids points to the possibility of Earth-sized planets in the same system.

The pulverized material may have been pulled into a ring around the stars and eventually funneled onto the dead stars. The silicon may have come from asteroids that were shredded by the white dwarfs' gravity when they veered too close to the dead stars.


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