Climate Sciences and the Climate Center of JPL

Understanding the far-reaching effects of climate change and how to adapt to these effects is one of the great challenges facing society today. Underpinning this challenge is the need to strengthen our understanding of the science and improve on our ability to project the future change, particularly at the regional scale. The factors that connect the buildup of CO2 to global warming require improvements in our understanding which come use of a variety of earth observations that are both available today and planned for tomorrow.

JPL lies at the forefront of key areas of the climate sciences both in developing the critical global observations of Earth required to meet these significant challenges as well as in advancing our understanding of key climate processes on many different fronts. This talk will place many aspects of the research pursued at JPL in this larger context. The JPL-based Earth science highlighted will include:

• Basic research on understanding cryospheric changes, including the loss of ice from the world’s ice sheets and subsequent challenges in modeling this ice loss.
• The monitoring of sea level rise and the challenges in understanding the factors that produce this rise and the projections of future rise.
• The planetary energy balance, our understanding of it, how it is expected to change and where gaps exist in our understanding of the change.
• The carbon cycle – how research at JPL is leading the community in a growing understanding of the carbon cycle and strategies to manage it.
• The water cycle, its component parts including clouds, precipitation, water vapor and surface and subsurface water. New ways to fingerprint the processes that shape the water cycle and determine how it is changing will be emphasized.

One of the ways these important advances are being used is through an ongoing and focused effort to evaluate Earth system models in an attempt to place some level of ultimate confidence on their projections. An important activity led by JPL is the Earth system model evaluation effort carried out in partnership with PCMDI. Highlights of this effort, drawn from the research activities above, will be described.

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Vesta Likely Cold and Dark Enough for Ice

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Though generally thought to be quite dry, roughly half of the giant asteroid Vesta is expected to be so cold and to receive so little sunlight that water ice could have survived there for billions of years, according to the first published models of Vesta's average global temperatures and illumination by the sun.

"Near the north and south poles, the conditions appear to be favorable for water ice to exist beneath the surface," says Timothy Stubbs of NASA's Goddard Space Flight Center in Greenbelt, Md., and the University of Maryland, Baltimore County. Stubbs and Yongli Wang of the Goddard Planetary Heliophysics Institute at the University of Maryland published the models in the January 2012 issue of the journal Icarus. The models are based on information from telescopes including NASA's Hubble Space Telescope.

Vesta, the second-most massive object in the asteroid belt between Mars and Jupiter, probably does not have any significant permanently shadowed craters where water ice could stay frozen on the surface all the time, not even in the roughly 300-mile-diameter (480-kilometer-diameter) crater near the south pole, the authors note. The asteroid isn't a good candidate for permanent shadowing because it is tilted on its axis at about 27 degrees, which is even greater than Earth's tilt of roughly 23 degrees. In contrast, the moon, which does have permanently shadowed craters, is tilted at only about 1.5 degrees. As a result of its large tilt, Vesta has seasons, and every part of the surface is expected to see the sun at some point during Vesta's year.

The presence or absence of water ice on Vesta tells scientists something about the tiny world's formation and evolution, its history of bombardment by comets and other objects, and its interaction with the space environment. Because similar processes are common to many other planetary bodies, including the moon, Mercury and other asteroids, learning more about these processes has fundamental implications for our understanding of the solar system as a whole. This kind of water ice is also potentially valuable as a resource for further exploration of the solar system.

Though temperatures on Vesta fluctuate during the year, the model predicts that the average annual temperature near Vesta's north and south poles is less than roughly minus 200 degrees Fahrenheit (145 kelvins). That is the critical average temperature below which water ice is thought to be able to survive in the top 10 feet or so (few meters) of the soil, which is called regolith.

Source: http://www.jpl.nasa.gov/news/news.cfm?release=2012-024

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Planck Telescope Warms up as Planned

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The High Frequency Instrument aboard the Planck space telescope has completed its survey of the remnant light from the Big Bang explosion that created our universe. The sensor ran out of coolant on Jan. 14, as expected, ending its ability to detect this faint energy.

"The High Frequency Instrument has reached the end of its observing life, but the Low Frequency Instrument will continue observing for another year, and analysis of data from both instruments is still in the early phase," said Charles Lawrence, the U.S. Planck project scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "The scientific payoff from the High Frequency Instrument's brilliantly successful operation is still to come."

NASA plays an important role in the Planck mission, which is led by the European Space Agency. In addition to helping with the analysis of the data, NASA contributed several key components to the mission itself. JPL built the state-of-the-art detectors that allowed the High Frequency Instrument to detect icy temperatures down to nearly absolute zero, the coldest temperature theoretically attainable.

Less than half a million years after the universe was created 13.7 billion years ago, the initial fireball cooled to temperatures of about 4,000 degrees Celsius (about 7,200 degrees Fahrenheit), releasing bright, visible light. As the universe has expanded, it has cooled dramatically, and its early light has faded and shifted to microwave wavelengths.

By studying patterns imprinted in that light today, scientists hope to understand the Big Bang and the very early universe, as it appeared long before galaxies and stars first formed.

Planck has been measuring these patterns by surveying the whole sky with its High Frequency Instrument and its Low Frequency Instrument. Combined, they give Planck unparalleled wavelength coverage and the ability to resolve faint details.

Launched in May 2009, the minimum requirement for success was for the spacecraft to complete two whole surveys of the sky. In the end, Planck worked perfectly in completing not two, but five whole-sky surveys with both instruments.

The Low Frequency Instrument will continue surveying the sky for a large part of 2012, providing data to improve the quality of the final results. The first results on the Big Bang and very early universe will not come for another year.

Read the full European Space Agency news release at http://www.esa.int/SPECIALS/Planck/SEMXWNMXDXG_0.html .

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Cassini Testing Part of Its Radio System

Engineers with NASA's Cassini mission are conducting diagnostic testing on a part of the spacecraft's radio system after its signal was not detected on Earth during a tracking pass in late December. The spacecraft has been communicating with Earth using a backup part.

The issue occurred with the ultra-stable oscillator, which is used for one type of radio science experiment and also as a means of sending data back to Earth. The spacecraft is currently using an auxiliary oscillator, whose frequency stability is adequate for transmitting data from the spacecraft to Earth. Tests later this month will help mission managers decide whether it will be possible to bring the ultra-stable oscillator back into service.

Some of the data collected for the radio science experiment using the auxiliary oscillator will be of lesser quality than that from the ultra-stable oscillator. Signals used for occultation experiments - where scientists analyze how radio signals are affected as they travel through Saturn's rings or the atmospheres of Saturn and its moons back to Earth - will be of lesser quality. A second kind of radio science investigation using gravity measurements to probe the internal structure of Saturn or its moons will not be affected. Cassini carries 12 science experiments.

The cause is still under investigation, but age may be a factor. The spacecraft launched in 1997 and has orbited Saturn since 2004. Cassini completed its prime mission in 2008 and has had two additional mission extensions. This is the first time its ultra-stable oscillator has had an issue.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. NASA's Jet Propulsion Laboratory in Pasadena manages the mission for the agency's Science Mission Directorate in Washington.

For more information about the mission, visit: http://saturn.jpl.nasa.gov and http://www.nasa.gov/cassini.

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Trajectory Maneuver Slated for Jan. 11

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An engine firing on Jan. 11 will be the biggest maneuver that NASA's Mars Science Laboratory spacecraft will perform on its flight between Earth and Mars.

The action will use a choreographed sequence of firings of eight thruster engines during a period of about 175 minutes beginning at 3 p.m. PST (6 p.m. EST or 2300 Universal Time). It will redirect the spacecraft more precisely toward Mars to land at Gale Crater. The trajectory resulting from the mission's Nov. 26, 2011, launch intentionally misses Mars to prevent the upper stage of the launch vehicle from hitting the planet. That upper stage was not cleaned the way the spacecraft itself was to protect Mars from Earth's microbes.

The maneuver is designed to impart a velocity change of about 12.3 miles per hour (5.5 meters per second).

"We are well into cruise operations, with a well-behaved spacecraft safely on its way to Mars," said Mars Science Laboratory Cruise Mission Manager Arthur Amador, of NASA's Jet Propulsion Laboratory, Pasadena, Calif. "After this trajectory correction maneuver, we expect to be very close to where we ultimately need to be for our entry point at the top of the Martian atmosphere."

The mission's schedule before arrival at Mars on Aug. 5 in PDT (Aug. 6 in Universal Time and EDT) includes opportunities for five more flight path correction maneuvers, as needed, for fine tuning.

The Jan. 11 maneuver has been planned to use the spacecraft's inertial measurement unit to measure the spacecraft's orientation and acceleration during the maneuver. A calibration maneuver using the gyroscope-containing inertial measurement unit was completed successfully on Dec. 21. The inertial measurement unit is used as an alternative to the spacecraft's onboard celestial navigation system due to an earlier computer reset.

Diagnostic work continues in response to the reset triggered by use of star-identifying software on the spacecraft on Nov. 29. In tests at JPL, that behavior has been reproduced a few times out of thousands of test runs on a duplicate of the spacecraft's computer, but no resets were triggered during similar testing on another duplicate. The spacecraft itself has redundant main computers. While the spacecraft is operating on the "A side" computer, engineers are beginning test runs of the star-identifying software on the redundant "B side" computer to check whether it is susceptible to the same reset behavior.

The Mars Science Laboratory mission will use its car-size rover, Curiosity, to investigate whether the selected region on Mars inside Gale Crater has offered environmental conditions favorable for supporting microbial life and favorable for preserving clues about whether life existed.

Source: http://www.jpl.nasa.gov/news/news.cfm?release=2012-004

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Spacecraft Reunite in Lunar Orbit

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During GRAIL's science mission, the two spacecraft will transmit radio signals precisely defining the distance between them. As they fly over areas of greater and lesser gravity caused by visible features such as mountains and craters, and masses hidden beneath the lunar surface, the distance between the two spacecraft will change slightly.

Scientists will translate this information into a high-resolution map of the moon's gravitational field. The data will allow scientists to understand what goes on below the lunar surface. This information will increase knowledge of how Earth and its rocky neighbors in the inner solar system developed into the diverse worlds we see today.

Each spacecraft carries a small camera called GRAIL MoonKAM (Moon Knowledge Acquired by Middle school students) with the sole purpose of education and public outreach. The MoonKAM program is led by Sally Ride, America's first woman in space, and her team at Sally Ride Science in collaboration with undergraduate students at the University of California in San Diego.

GRAIL MoonKAM will engage middle schools across the country in the GRAIL mission and lunar exploration. Thousands of fifth- to eighth-grade students will select target areas on the lunar surface and send requests to the GRAIL MoonKAM Mission Operations Center in San Diego. Photos of the target areas will be sent back by the GRAIL satellites for students to study.

A student contest that began in October 2011 also will choose new names for the spacecraft. The new names are scheduled to be announced in January 2012. Ride and Maria Zuber, the mission's principal investigator at the Massachusetts Institute of Technology in Cambridge, chaired the final round of judging.

NASA's Jet Propulsion Laboratory in Pasadena, Calif., manages the GRAIL mission for NASA's Science Mission Directorate, Washington. The GRAIL mission is part of the Discovery Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. Lockheed Martin Space Systems in Denver built the spacecraft. JPL is a division of the Çalifornia Institute of Technology in Pasadena.

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NASA's Cassini Delivers Holiday Treats From Saturn

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No team of reindeer, but radio signals flying clear across the solar system from NASA's Cassini spacecraft have delivered a holiday package of glorious images. The pictures, from Cassini's imaging team, show Saturn's largest, most colorful ornament, Titan, and other icy baubles in orbit around this splendid planet.

The release includes images of satellite conjunctions in which one moon passes in front of or behind another. Cassini scientists regularly make these observations to study the ever-changing orbits of the planet's moons. But even in these routine images, the Saturnian system shines. A few of Saturn's stark, airless, icy moons appear to dangle next to the orange orb of Titan, the only moon in the solar system with a substantial atmosphere. Titan's atmosphere is of great interest because of its similarities to the atmosphere believed to exist long ago on the early Earth.

The images are online at: http://www.nasa.gov/cassini , http://saturn.jpl.nasa.gov and http://ciclops.org .

While it may be wintry in Earth's northern hemisphere, it is currently northern spring in the Saturnian system and it will remain so for several Earth years. Current plans to extend the Cassini mission through 2017 will supply a continued bounty of scientifically rewarding and majestic views of Saturn and its moons and rings, as spectators are treated to the passage of northern spring and the arrival of summer in May 2017.

"As another year traveling this magnificent sector of our solar system draws to a close, all of us on Cassini wish all of you a very happy and peaceful holiday season, " said Carolyn Porco, Cassini imaging team lead at the Space Science Institute, Boulder, Colo.

More information about Cassini mission is online at http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov .

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 Cassini-Huygens mission for NASA's Science Mission Directorate, Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute in Boulder, Colo.

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NASA Shuts Doors, Pulls Plug on Shuttle Discovery

NASA powered down the space shuttle Discovery for a final time Friday (Dec. 16), more than 28 years after the agency's retired fleet leader first came alive. The vehicle was "unplugged" inside Orbiter Processing Facility-1 (OPF-1) at the Kennedy Space Center in Florida.

The electrical shutdown, which came soon after technicians closed the shuttle's twin 60-foot (18.3-meter) long payload bay doors, was a milestone in Discovery's transition from a space-worthy orbiter to a museum exhibit. The shuttle, the oldest of NASA's remaining orbiters, is destined for display next spring at the Smithsonian National Air and Space Museum's Steven F. Udvar-Hazy Center in Virginia.

Discovery's cargo hold — which carried to orbit the Hubble Space Telescope and Ulysses solar probe along with modules for the International Space Station and more than a dozen satellites — was closed for what may be its last time. The Smithsonian plans to display the shuttle with its bay doors shut, at least initially.

The power down was much more permanent. Though Discovery's three electricity-generating fuel cells were reinstalled last week, they were first drained of all their reactants, and their feed lines were purged. Other than serving as an engineering example for researchers, they will never work again.

As a result, the shuttle's glass cockpit with its multiple computer screens and its backlit switches will from now on be dark. [Photos: See Inside Space Shuttle Discovery]

Since landing back on Earth after its 39th and final mission in March, Discovery has been carefully taken apart to preserve some of its components for future use while making the vehicle safe for public display. Its engines have been removed and replaced with replicas and its thrusters cleaned of their hazardous materials.

Inside its crew cabin, Discovery's waste collection system — otherwise known as its toilet — was removed, cleaned, and replaced, and its flight deck configured to appear ready for another mission, one that will never come. As with the fuel cells, the Smithsonian requested NASA keep Discovery as complete as possible so as to serve as a resource for future study.

Discovery is targeted to make one last flight in April 2012, though not under its own power and well within the atmosphere. Ferried atop NASA's modified Boeing 747 carrier aircraft, the shuttle will be flown to Dulles Airport in Virginia. There it will be unloaded by cranes and rolled into the Udvar-Hazy's James S. McDonnell Space Hangar as its centerpiece attraction.

Discovery will replace the prototype shuttle Enterprise, which the Udvar-Hazy has displayed since 2003. Enterprise in turn will be flown to New York City, where it is to go on exhibit at the Intrepid Sea, Air & Space Museum.

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Space Observatory Provides Clues to Creation of Earth's Oceans

Astronomers have found a new cosmic source for the same kind of water that appeared on Earth billions of years ago and created the oceans. The findings may help explain how Earth's surface ended up covered in water.

New measurements from the Herschel Space Observatory show that comet Hartley 2, which comes from the distant Kuiper Belt, contains water with the same chemical signature as Earth's oceans. This remote region of the solar system, some 30 to 50 times as far away as the distance between Earth and the sun, is home to icy, rocky bodies including Pluto, other dwarf planets and innumerable comets.

"Our results with Herschel suggest that comets could have played a major role in bringing vast amounts of water to an early Earth," said Dariusz Lis, senior research associate in physics at the California Institute of Technology in Pasadena and co-author of a new paper in the journal Nature, published online today, Oct. 5. "This finding substantially expands the reservoir of Earth ocean-like water in the solar system to now include icy bodies originating in the Kuiper Belt."

Scientists theorize Earth started out hot and dry, so that water critical for life must have been delivered millions of years later by asteroid and comet impacts. Until now, none of the comets previously studied contained water like Earth's. However, Herschel's observations of Hartley 2, the first in-depth look at water in a comet from the Kuiper Belt, paint a different picture.

Herschel peered into the comet's coma, or thin, gaseous atmosphere. The coma develops as frozen materials inside a comet vaporize while on approach to the sun. This glowing envelope surrounds the comet's "icy dirtball"-like core and streams behind the object in a characteristic tail.

Herschel detected the signature of vaporized water in this coma and, to the surprise of the scientists, Hartley 2 possessed half as much "heavy water" as other comets analyzed to date. In heavy water, one of the two normal hydrogen atoms has been replaced by the heavy hydrogen isotope known as deuterium. The ratio between heavy water and light, or regular, water in Hartley 2 is the same as the water on Earth's surface. The amount of heavy water in a comet is related to the environment where the comet formed.

By tracking the path of Hartley 2 as it swoops into Earth's neighborhood in the inner solar system every six-and-a-`half years, astronomers know that it comes from the Kuiper Belt. The five comets besides Hartley 2 whose heavy-water-to-regular-water ratios have been obtained all come from an even more distant region in the solar system called the Oort Cloud. This swarm of bodies, 10,000 times farther afield than the Kuiper Belt, is the wellspring for most documented comets.

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Cassini Spacecraft Captures Images and Sounds of Big Saturn Storm

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Scientists analyzing data from NASA's Cassini spacecraft now have the first-ever, up-close details of a Saturn storm that is eight times the surface area of Earth.

On Dec. 5, 2010, Cassini first detected the storm that has been raging ever since. It appears approximately 35 degrees north latitude of Saturn. Pictures from Cassini's imaging cameras show the storm wrapping around the entire planet covering approximately 2 billion square miles (4 billion square kilometers).

The storm is about 500 times larger than the biggest storm previously seen by Cassini during several months from 2009 to 2010. Scientists studied the sounds of the new storm's lightning strikes and analyzed images taken between December 2010 and February 2011. Data from Cassini's radio and plasma wave science instrument showed the lightning flash rate as much as 10 times more frequent than during other storms monitored since Cassini's arrival to Saturn in 2004. The data appear in a paper published this week in the journal Nature.

"Cassini shows us that Saturn is bipolar," said Andrew Ingersoll, an author of the study and a Cassini imaging team member at the California Institute of Technology in Pasadena, Calif. "Saturn is not like Earth and Jupiter, where storms are fairly frequent. Weather on Saturn appears to hum along placidly for years and then erupt violently. I'm excited we saw weather so spectacular on our watch."

At its most intense, the storm generated more than 10 lightning flashes per second. Even with millisecond resolution, the spacecraft's radio and plasma wave instrument had difficulty separating individual signals during the most intense period. Scientists created a sound file from data obtained on March 15 at a slightly lower intensity period.

Cassini has detected 10 lightning storms on Saturn since the spacecraft entered the planet's orbit and its southern hemisphere was experiencing summer, with full solar illumination not shadowed by the rings. Those storms rolled through an area in the southern hemisphere dubbed "Storm Alley." But the sun's illumination on the hemispheres flipped around August 2009, when the northern hemisphere began experiencing spring.

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