Nasa Space news - Rosetta: To Chase a Comet

Comets are among the most beautiful and least understood nomads of the night sky. To date, half a dozen of these most heavenly of heavenly bodies have been visited by spacecraft in an attempt to unlock their secrets. All these missions have had one thing in common: the high-speed flyby. Like two ships passing in the night (or one ship and one icy dirtball), they screamed past each other at hyper velocity -- providing valuable insight, but fleeting glimpses, into the life of a comet. That is, until Rosetta.



NASA is participating in the European Space Agency's Rosetta mission, whose goal is to observe one such space-bound icy dirt ball from up close -- for months on end. The spacecraft, festooned with 25 instruments between its lander and orbiter (including three from NASA), is programmed to "wake up" from hibernation on Jan. 20. After a check-out period, it will monitor comet 67P/Churyumov-Gerasimenko as it makes its nosedive into, and then climb out of, the inner solar system. Over 16 months, during which old 67P is expected to transform from a small, frozen world into a roiling mass of ice and dust, complete with surface eruptions, mini-earthquakes, basketball-sized, fluffy ice particles and spewing jets of carbon dioxide and cyanide.

"We are going to be in the cometary catbird seat on this one," said Claudia Alexander, project scientist for U.S. Rosetta from NASA's Jet Propulsion Laboratory in Pasadena, Calif.  "To have an extended presence in the neighborhood of a comet as it goes through so many changes should change our perspective on what it is to be a comet."

Since work began on Rosetta back in 1993, scientists and engineers from all over Europe and the United States have been combining their talents to build an orbiter and a lander for this unique expedition.  NASA's contribution includes three of the orbiter's instruments (an ultraviolet spectrometer called Alice; the Microwave Instrument for Rosetta Orbiter; and the Ion and Electron Sensor. NASA is also providing part of the electronics package for an instrument called the Double Focusing Mass Spectrometer, which is part of the Swiss-built Rosetta Orbiter Spectrometer for Ion and Neutral Analysis instrument. NASA is also providing U.S. science investigators for selected non-U.S. instruments and is involved to a greater or lesser degree in seven of the mission's 25 instruments. NASA's Deep Space Network provides support for ESA's Ground Station Network for spacecraft tracking and navigation.

"All the instruments aboard Rosetta and the Philae lander are designed to work synergistically," said Sam Gulkis of JPL, the principal investigator for the Microwave Instrument for Rosetta Orbiter. "They will all work together to create the most complete picture of a comet to date, telling us how the comet works, what it is made of, and what it can tell us about the origins of the solar system."

The three NASA-supplied instruments are part of the orbiter's scientific payload. Rosetta's Microwave Instrument for Rosetta Orbiter specializes in the thermal properties. The instrument combines a spectrometer and radiometer, so it can sense temperature and identify chemicals located on or near the comet's surface, and even in the dust and ices jetting out from it. The instrument will also see the gaseous activity through the dusty cloud of material.  Rosetta scientists will use it to determine how different materials in the comet change from ice to gas, and to observe how much it changes in temperature as it approaches the sun.

Like the Microwave for Rosetta Orbiter, the Alice instrument contains a spectrometer. But Alice looks at the ultraviolet portion of the spectrum. Alice will analyze gases in the coma and tail and measure the comet’s production rates of water and carbon monoxide and dioxide. It will provide information on the surface composition of the nucleus, and make a potentially key measurement of argon, which will be a big clue about what the temperature was in the primordial solar system when the comet's nucleus originally formed (more than 4.6 billion years ago).

Magnetic Arcs

An M5 flare (medium-size) associated with a coronal mass ejection generated a fairly robust radiation storm (May 22-23, 2013). The outburst originated from active region right near the right edge of the Sun. After the eruption, cascades of magnetic loops spun up above the area as the magnetic fields tried to reorganize themselves. When viewed in profile, they put on a marvelous display of solar activity. The images are a combination of two wavelengths of extreme ultraviolet light (at 171 and 304 Angstroms). Credit: NASA's Solar Dynamics Observatory.

Swirls along an Ice Highway - Nasa Images

Sea water off the east coast of Greenland looked a bit like marbled paper in October 2012. The shifting swirls of white were sea ice, as observed by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite on October 17, 2012. In fact, this ice moved discernibly between October 16 and October 17. Thin, free-drifting ice moves very easily with winds and currents.



Each year, Arctic sea ice grows through the winter, reaching its maximum extent around March. It then melts through the summer, reaching its minimum in September. By October, Arctic waters start freezing again. However, the ice in the image above is more likely a remnant of old ice that migrated down to the coast of Greenland. Sea water is unlikely to start freezing this far south in October.



Along Greenland’s east coast, the Fram Strait serves as an expressway for sea ice moving out of the Arctic Ocean. The movement of ice through the strait used to be offset by the growth of ice in the Beaufort Gyre. Until the late 1990s, ice would persist in the gyre for years, growing thicker and more resistant to melt. Since the start of the twenty-first century, however, ice has been less likely to survive its trip through the southern part of the Beaufort Gyre. As a result, less Arctic sea ice has been able to pile up and form multi-year ice.

With less thick ice there is less Arctic sea ice volume, something the researchers at the Polar Science Center at the University of Washington have modeled from 1979 to 2012. Their results appear in the graph above. The model indicates that ice volume peaks in March through May of each year and reaches its lowest levels from August through October. But while the seasonal timing of the peaks and valleys has remained consistent since 1979, the total sea ice volume has declined.

The thick blue line is the 1979–2000 average, and the lighter blue bands surrounding it are one and two standard deviations from the median. The lines below the blue line are the calculated sea ice volumes for the years since 2000. All of them fall below the median, and almost all of them fall below two standard deviations.

The drop in sea ice volume is consistent with other observed changes in Arctic sea ice. In terms of sea ice extent, the National Snow and Ice Data Center and NASA reported that Arctic sea ice set a record low in September 2012.

NASA Released January Solar Flare Images

The sun emitted a mid-level solar flare, peaking at 5:13 a.m. EST on Jan. 7, 2014. Images of the flare were captured by NASA's Solar Dynamics Observatory and showed that it came from an active region on the sun that currently sports one of the largest sunspots seen in the last 10 years. Sunspots are regions of strong and complex magnetic fields on the sun's surface.



Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however -- when intense enough -- they can disturb the atmosphere in the layer where GPS and communications signals travel.



To see how this event may impact Earth, please visit NOAA's Space Weather Prediction Center at http://spaceweather.gov, the U.S. government's official source for space weather forecasts, alerts, watches and warnings.

This flare is classified as an M7.2-class flare.

Swilling Stormy Stars present on cool celestial orbs

Swirling, stormy clouds may be ever-present on cool celestial orbs called brown dwarfs. New observations from NASA's Spitzer Space Telescope suggest that most brown dwarfs are roiling with one or more planet-size storms akin to Jupiter's "Great Red Spot." "As the brown dwarfs spin on their axis, the alternation of what we think are cloud-free and cloudy regions produces a periodic brightness variation that we can observe," said Stanimir Metchev of the University of Western Ontario, Canada. "These are signs of patchiness in the cloud cover."



In a Spitzer program named "Weather on Other Worlds," astronomers used the infrared space telescope to watch 44 brown dwarfs as they rotated on their axis for up to 20 hours. Previous results had suggested that some brown dwarfs have turbulent weather, so the scientists had expected to see a small fraction vary in brightness over time. However, to their surprise, half of the brown dwarfs showed the variations. When you take into account that half of the objects would be oriented in such a way that their storms would be either hidden or always in view and unchanging, the results indicate that most, if not all, brown dwarfs are racked by storms.

"We needed Spitzer to do this," said Metchev. "Spitzer is in space, above the thermal glow of the Earth's atmosphere, and it has the sensitivity required to see variations in the brown dwarfs' brightness."
The results led to another surprise as well. Some of the brown dwarfs rotated much more slowly than any previously measured, a finding that could not have been possible without Spitzer's long, uninterrupted observations from space. Astronomers had thought that brown dwarfs sped up to very fast rotations when they formed and contracted, and that this rotation didn't wind down with age.

"We don't yet know why these particular brown dwarfs spin so slowly, but several interesting possibilities exist," said Heinze.  "A brown dwarf that rotates slowly may have formed in an unusual way -- or it may even have been slowed down by the gravity of a yet-undiscovered planet in a close orbit around it."

The work may lead to a better understanding of not just brown dwarfs but their "little brothers": the gas-giant planets. Researchers say that studying the weather on brown dwarfs will open new windows onto weather on planets outside our solar system, which are harder to study under the glare of their stars. Brown dwarfs are weather laboratories for planets, and, according to the new results, those laboratories are everywhere.

Orbital Launch Rescheduled for Jan. 8 - Nasa Space news

The International Space Station Program and Orbital Sciences Corporation have decided to postpone the launch of the Antares rocket and its Cygnus cargo craft on the first Orbital commercial resupply mission to the space station to no earlier than Wednesday, Jan. 8 due to the forecast of cold temperatures for Tuesday, Jan. 7 at the launch site at NASA’s Wallops Flight Facility in Virginia.

The forecast for Wednesday also calls for cold temperatures, but the station program and Orbital plan to revisit the weather forecast at the beginning of the week. The main concern with the weather is the cold temperatures coupled with likely precipitation. Orbital says the Antares rocket has a lower limit temperature constraint of 20 degrees Fahrenheit.

Orbital still plans to roll out its Antares rocket to Launch Pad 0A at Wallops on Saturday night because the weather is forecast to be favorable at that time. The launch time for Wednesday, Jan. 8 is 1:32 p.m. Eastern time. NASA TV coverage of launch will begin at 1 p.m.

A launch on Wednesday will result in a grapple of Cygnus by the Expedition 38 crew aboard the station on Sunday, Jan. 12 at 6:02 a.m. NASA TV coverage will begin at 5 a.m. Coverage of the installation of Cygnus on the Earth-facing port of the Harmony module will begin at 7 a.m.

Two Solar Flares Welcomes 2014 - Nasa Space News

The sun ushered out 2013 and welcomed 2014 with two mid-level flares on Dec. 31, 2013 and Jan. 1, 2014. Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however -- when intense enough -- they can disturb the atmosphere in the layer where GPS and communications signals travel. This disrupts the radio signals for as long as the flare is ongoing, anywhere from minutes to hours.



To see how this event may impact Earth, please visit NOAA's Space Weather Prediction Center at http://spaceweather.gov, the U.S. government's official source for space weather forecasts, alerts, watches and warnings.



The first flare (below) was categorized as an M6.4 and it peaked at 4:58 p.m EST on Dec. 31. The second (above) was categorized as an M9.9 and peaked at 1:52 p.m. EST on Jan. 1. Both flares emerged from the same active region on the sun, AR1936. Imagery of the flares was captured by NASA's Solar Dynamics Observatory, which keeps a constant watch on the sun, collecting new data every 12 seconds.

Cassini Sees Saturn and Moons - Nasa Space News

"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 Videos

NASA's DSN - 'Wireless Network' Turns 50

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).

For more

DSN's Eight Facts - Nasa Space News

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.

Amazing Picture for WISE's Fourth Anniversary

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.

Atmosphere of Venus

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.


For  more
http://www.nasa.gov/content/goddard/sounding-rocket-to-peek-at-atmosphere-of-venus/

Boeing Completes New Spacecraft, Rocket Milestones


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. 

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