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  • richardmitnick 1:28 pm on November 17, 2014 Permalink | Reply
    Tags: , , , , , NASA Insight, NASA JPL   

    From JPL: “Next NASA Mars Mission Reaches Milestone” 

    JPL

    November 17, 2014
    Media Contact
    Guy Webster
    Jet Propulsion Laboratory, Pasadena, Calif.
    818-354-6278
    guy.webster@jpl.nasa.gov

    Dwayne Brown
    NASA Headquarters, Washington
    202-358-1726
    dwayne.c.brown@nasa.gov

    Gary Napier
    Lockheed Martin Space Systems, Denver
    303-971-4012
    gary.p.napier@lmco.com

    NASA’s InSight mission has begun the assembly, test and launch operations (ATLO) phase of its development, on track for a March 2016 launch to Mars.

    The lander, its aeroshell and cruise stage are being assembled by Lockheed Martin Space Systems, Denver.

    techs
    Technicians in a Lockheed Martin clean room near Denver prepare NASA’s InSight Mars lander for propulsion proof and leak testing on Oct. 31, 2014.

    “Reaching this stage that we call ATLO is a critical milestone,” said InSight Project Manager Tom Hoffman at NASA’s Jet Propulsion Laboratory, Pasadena, California. “This is a very satisfying point of the mission as we transition from many teams working on their individual elements to integrating these elements into a functioning system. The subsystems are coming from all over the globe, and the ATLO team works to integrate them into the flight vehicle. We will then move rapidly to rigorous testing when the spacecraft has been assembled, and then to the launch preparations.”

    NASA Insight
    NASA/InSight

    Over the next six months, technicians at Lockheed Martin will add subsystems such as avionics, power, telecomm, mechanisms, thermal systems and navigation systems onto the spacecraft. The propulsion system was installed earlier this year on the lander’s main structure.

    “The InSight mission is a mix of tried-and-true and new-and-exciting. The spacecraft has a lot of heritage from Phoenix and even back to the Viking landers, but the science has never been done before at Mars,” said Stu Spath, InSight program manager at Lockheed Martin Space Systems. “Physically, InSight looks a lot like the Phoenix lander we built, but most of the electronic components are similar to what is currently flying on the MAVEN spacecraft.”

    NASA Phoenix
    NASA/Phoenix

    NASA Viking 1
    NASA/Viking 1

    InSight stands for “Interior Exploration using Seismic Investigations, Geodesy and Heat Transport,” and it is more than a Mars mission. This NASA Discovery-class mission is a terrestrial planet explorer that will address one of the most fundamental issues of planetary and solar system science: understanding the processes that shaped the rocky planets of the inner solar system (including Earth) more than four billion years ago.

    To investigate the planet’s interior, the stationary lander will carry a robotic arm that will deploy surface and burrowing instruments contributed by France and Germany. The national space agencies of France and Germany — Centre National d’Etudes Spatiales (CNES) and Deutsches Zentrum für Luft- und Raumfahrt (DLR), respectively — are partnering with NASA by providing InSight’s two main science instruments.

    The Seismic Experiment for Interior Structure (SEIS) will be built by CNES in partnership with DLR and the space agencies of Switzerland and the United Kingdom. It will measure waves of ground motion carried through the interior of the planet, from “marsquakes” and meteor impacts. The Heat Flow and Physical Properties Package, from DLR, will measure heat coming toward the surface from the planet’s interior.

    Guided by images of the surroundings taken by the lander, InSight’s robotic arm will place the seismometer on the surface and then place a protective covering over it to minimize effects of wind and temperature on the sensitive instrument. The arm will also put the heat-flow probe in position to hammer itself into the ground to a depth of 3 to 5 yards, or meters.

    Another experiment will use the radio link between InSight and NASA’s Deep Space Network antennas on Earth to measure precisely a wobble in Mars’ rotation that could reveal whether the planet has a molten or solid core. Wind and temperature sensors from Spain’s Centro de Astrobiologia and a pressure sensor will monitor weather at the landing site, and a magnetometer will measure magnetic disturbances caused by the Martian ionosphere.

    The InSight mission is led by JPL’s Bruce Banerdt. It is part of NASA’s Discovery Program of competitively selected, cost-capped missions. Its international science team combines researchers from Austria, Belgium, Canada, France, Germany, Japan, Poland, Spain, Switzerland, the United Kingdom and the United States. JPL, a division of the California Institute of Technology, Pasadena, manages InSight for NASA’s Science Mission Directorate, Washington. NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages the Discovery Program. Lockheed Martin is building the lander and other parts of the spacecraft near Denver.

    For more about InSight, visit:

    http://insight.jpl.nasa.gov

    For more information about Mars missions:

    http://www.nasa.gov/mars

    For more about the Discovery Program, visit:

    http://discovery.nasa.gov

    See the full article here.

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    Stem Education Coalition

    NASA JPL Campus

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

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  • richardmitnick 5:21 pm on November 14, 2014 Permalink | Reply
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    From JPL: “New Map Shows Frequency of Small Asteroid Impacts, Provides Clues on Larger Asteroid Population” 

    JPL

    November 14, 2014
    Media Contact
    DC Agle
    Jet Propulsion Laboratory, Pasadena, Calif.
    818-393-9011
    agle@jpl.nasa.gov

    Dwayne Brown
    NASA Headquarters, Washington
    202-358-1726
    dwayne.c.brown@nasa.gov

    bolide
    This diagram maps the data gathered from 1994-2013 on small asteroids impacting Earth’s atmosphere to create very bright meteors, technically called “bolides” and commonly referred to as “fireballs”. Sizes of red dots (daytime impacts) and blue dots (nighttime impacts) are proportional to the optical radiated energy of impacts measured in billions of Joules (GJ) of energy, and show the location of impacts from objects about 1 meter (3 feet) to almost 20 meters (60 feet) in size. Image Credit: Planetary Science

    A map released today by NASA’s Near Earth Object (NEO) Program reveals that small asteroids frequently enter and disintegrate in the Earth’s atmosphere with random distribution around the globe. Released to the scientific community, the map visualizes data gathered by U.S. government sensors from 1994 to 2013. The data indicate that Earth’s atmosphere was impacted by small asteroids, resulting in a bolide (or fireball), on 556 separate occasions in a 20-year period. Almost all asteroids of this size disintegrate in the atmosphere and are usually harmless. The notable exception was the Chelyabinsk event which was the largest asteroid to hit Earth in this period. The new data could help scientists better refine estimates of the distribution of the sizes of NEOs including larger ones that could pose a danger to Earth.

    Finding and characterizing hazardous asteroids to protect our home planet is a high priority for NASA. It is one of the reasons NASA has increased by a factor of 10 investments in asteroid detection, characterization and mitigation activities over the last five years. In addition, NASA has aggressively developed strategies and plans with its partners in the U.S. and abroad to detect, track and characterize NEOs. These activities also will help identify NEOs that might pose a risk of Earth impact, and further help inform developing options for planetary defense.

    The public can help participate in the hunt for potentially hazardous Near Earth Objects through the Asteroid Grand Challenge, which aims to create a plan to find all asteroid threats to human populations and know what to do about them. NASA is also pursuing an Asteroid Redirect Mission (ARM) which will identify, redirect and send astronauts to explore an asteroid. Among its many exploration goals, the mission could demonstrate basic planetary defense techniques for asteroid deflection.

    For more information about the map and data, go to:

    http://neo.jpl.nasa.gov

    For details about ARM, and the Asteroid Grand Challenge, visit:

    http://www.nasa.gov/asteroidinitiative

    See the full article here.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    NASA JPL Campus

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

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  • richardmitnick 11:15 am on October 31, 2014 Permalink | Reply
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    From NASA/JPL: “Specular Spectacular” 

    JPL

    October 30, 2014
    No Writer Credit

    This near-infrared, color mosaic from NASA’s Cassini spacecraft shows the sun glinting off of Titan’s north polar seas. While Cassini has captured, separately, views of the polar seas and the sun glinting off of them in the past, this is the first time both have been seen together in the same view.

    titan
    Image credit: NASA/JPL-Caltech/University of Arizona/University of Idaho

    NASA Cassini Spacecraft
    NASA/Cassini

    The sunglint, also called a specular reflection, is the bright area near the 11 o’clock position at upper left. This mirror-like reflection, known as the specular point, is in the south of Titan’s largest sea, http://en.wikipedia.org/wiki/Kraken_Mare, just north of an island archipelago separating two separate parts of the sea.

    This particular sunglint was so bright as to saturate the detector of Cassini’s Visual and Infrared Mapping Spectrometer (VIMS) instrument, which captures the view. It is also the sunglint seen with the highest observation elevation so far — the sun was a full 40 degrees above the horizon as seen from Kraken Mare at this time — much higher than the 22 degrees seen in PIA18433. Because it was so bright, this glint was visible through the haze at much lower wavelengths than before, down to 1.3 microns.

    The southern portion of Kraken Mare (the area surrounding the specular feature toward upper left) displays a “bathtub ring” — a bright margin of evaporate deposits — which indicates that the sea was larger at some point in the past and has become smaller due to evaporation. The deposits are material left behind after the methane & ethane liquid evaporates, somewhat akin to the saline crust on a salt flat.

    The highest resolution data from this flyby — the area seen immediately to the right of the sunglint — cover the labyrinth of channels that connect Kraken Mare to another large sea, Ligeia Mare. Ligeia Mare itself is partially covered in its northern reaches by a bright, arrow-shaped complex of clouds. The clouds are made of liquid methane droplets, and could be actively refilling the lakes with rainfall.

    The view was acquired during Cassini’s August 21, 2014, flyby of Titan, also referred to as “T104″ by the Cassini team.

    The view contains real color information, although it is not the natural color the human eye would see. Here, red in the image corresponds to 5.0 microns, green to 2.0 microns, and blue to 1.3 microns. These wavelengths correspond to atmospheric windows through which Titan’s surface is visible.

    The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology, Pasadena, manages the mission for NASA’s Science Mission Directorate in Washington. The VIMS team is based at the University of Arizona in Tucson.

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

    See the full article, with other material, here.

    NASA JPL Campus

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

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  • richardmitnick 2:22 pm on October 15, 2014 Permalink | Reply
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    From JPL at Caltech: “Slow-Growing Galaxies Offer Window to Early Universe” 

    JPL

    October 15, 2014
    Whitney Clavin
    818-354-4673
    Jet Propulsion Laboratory, Pasadena, Calif.
    whitney.clavin@jpl.nasa.gov

    What makes one rose bush blossom with flowers, while another remains barren? Astronomers ask a similar question of galaxies, wondering how some flourish with star formation and others barely bloom.

    A new study published in the Oct. 16 issue of the journal Nature addresses this question by making some of the most accurate measurements yet of the meager rates at which small, sluggish galaxies create stars. The report uses data from the European Space Agency’s Herschel mission, in which NASA is a partner, and NASA’s Spitzer Space Telescope and Galaxy Evolution Explorer (GALEX).

    ESA Herschel
    ESA Herschel schematic
    ESA/Herschel

    NASA Spitzer Telescope
    NASA Spitzer schematic
    NASA/Spitzer

    NASA Galex telescope
    NASA/GALEX

    The findings are helping researchers figure out how the very first stars in our universe sprouted. Like the stars examined in the new study, the first-ever stars from billions of years ago took root in poor conditions. Growing stars in the early cosmos is like trying to germinate flower seeds in a bed of dry, poor soil. Back then, the universe hadn’t had time yet to make “heavy metals,” elements heavier than hydrogen and helium.

    “The metals in space help act in some ways like a fertilizer to help stars grow,” said George Helou, an author of the new study and director of NASA’s Infrared Processing and Analysis Center (IPAC) at the California Institute of Technology, Pasadena. The lead author of the study is Yong Shi, who performed some of the research at IPAC before moving to Nanjing University in China.

    The two slow-going galaxies in the study, called Sextans A and ESO 146-G14, lack in heavy metals, just like our young and remote cosmos, only they are a lot closer to us and easier to see. Sextans A is located about 4,500 light-years from Earth, and ESO 146-G14 is more than 70,000 light-years away.

    sa
    Sextans A Dwarf galaxy

    These smaller galaxies are late bloomers. They managed to travel through history while remaining pristine, and never bulked up in heavy metals (heavy metals not only help stars to form, but are also created themselves by stars).

    “The metal-poor galaxies are like islands left over from the early universe,” said Helou. “Because they are relatively close to us, they are especially valuable windows to the past.”

    Studying star formation in poor growing environments such as these is tricky. The galaxies, though nearby, are still faint and hard to see. Shi and his international team wrangled the problem with a multi-wavelength approach. The Herschel data, captured at the longest infrared wavelengths of light, let the researchers see the cool dust in which stars are buried. The dust serves as a proxy for the total amount of gas in the region — the basic ingredient of stars. To other telescopes, this dust is cold and invisible. Herschel, on the other hand, can pick up its feeble glow.

    Supporting radio-wavelength measurements of some of the gas in the galaxies came from the National Radio Astronomy Observatory’s Jansky Very Large Array observatory near Socorro, New Mexico, and the Australia Telescope Compact Array observatory, near Narrabri.

    NRAO VLA
    NRAO VLA

    Australian Telescope Compact Array
    Australia Telescope Compact Array observatory

    Meanwhile, archived data from Spitzer and GALEX were used to look at the rate of star formation. Spitzer sees shorter-wavelength infrared light, which comes from dust that is warmed by new stars. GALEX images capture ultraviolet light from the shining stars themselves.

    Putting all these pieces together enabled the astronomers to determine that the galaxies are plodding along, creating stars at rates 10 times lower than their normal counterparts.

    “Star formation is very inefficient in these environments,” said Shi. “Extremely metal-poor nearby galaxies are the best way to know what went on billions of years ago.”

    The heavy metals in present-day galaxies help star formation to flourish through cooling effects. For a star to form, a ball of gas needs to fall in on itself with the help of its own gravity. Ultimately, the material has to become dense enough for atoms to fuse and ignite, creating starlight. But as this cloud collapses, it heats up and puffs back out again, counteracting the process. Heavy metals cool everything down by radiating away the heat, enabling the cloud to condense into a star.

    How stars in the early universe were able to do this without the cooling benefits of heavy metals remains unknown.

    Studies like this shine light on the very first stellar buds, giving us a glimpse into the roots of our cosmic history.

    NASA’s Jet Propulsion Laboratory, Pasadena, California, manages the Spitzer Space Telescope mission for NASA’s Science Mission Directorate, Washington. The GALEX mission, which ended in 2013, was also managed by JPL for NASA and led by Caltech. JPL served as the NASA Herschel Project Office for the European Space Agency’s Herschel mission, which also ended in 2013.

    Data from Spitzer and Herschel are accessible through the Infrared Science Archive housed at the Infrared Processing and Analysis Center at Caltech. Caltech manages JPL for NASA.

    See the full article here.

    NASA JPL Campus

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

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  • richardmitnick 4:42 pm on October 8, 2014 Permalink | Reply
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    From JPL at Caltech: “Metal Made Like Plastic May Have Big Impact” 

    JPL

    10.07.14
    Media Contact
    Elizabeth Landau
    NASA’s Jet Propulsion Laboratory, Pasadena, Calif.
    818-354-6425
    Elizabeth.Landau@jpl.nasa.gov

    Open a door and watch what happens — the hinge allows it to open and close, but doesn’t permanently bend. This simple concept of mechanical motion is vital for making all kinds of movable structures, including mirrors and antennas on spacecraft. Material scientists at NASA’s Jet Propulsion Laboratory in Pasadena, California, are working on new, innovative methods of creating materials that can be used for motion-based mechanisms.

    cuffs
    This image shows components of a mirror structure that can be rotated very precisely by flexing parts made of a material scientists call “bulk metallic glass.” Credit: NASA/JPL-Caltech

    When a device moves because metal is flexing but isn’t permanently deformed, that’s called a compliant mechanism. Compliant mechanisms are all around us — in springs, surgical instruments, paperclips, clothespins and even micro-devices.

    Researchers at JPL, Brigham Young University in Provo, Utah, and the California Institute of Technology in Pasadena, describe a new methodology for creating complex, low-cost compliant mechanisms using a combination of novel materials and manufacturing techniques in a recent paper featured on the cover of the journal Advanced Engineering Materials. They demonstrate that materials called “bulk metallic glasses” have highly desirable properties for these mechanisms. These “glasses,” as the scientists call them, are metal alloys designed to have a random arrangement of atoms.

    “We’ve demonstrated that these metals not only have desirable properties for applications where flexibility and durability are required, but can also be injection-molded like a plastic and made cheaply,” said Douglas Hofmann, principal investigator of the research at JPL. Hofmann is a researcher in material science and metallurgy at JPL, and visiting associate at Caltech. “It offers an entirely new industry for high-performance metals,” he said.

    “Traditionally, titanium alloys have been used in compliant mechanisms because they were the best materials for the job, but titanium was also difficult to work with,” said Larry Howell, professor at Brigham Young University and study co-author. The new research shows that bulk metallic glasses have twice the strength and conventional flexibility of titanium alloys, while also boasting low melting temperatures.

    “I had been working on flexible mechanisms for a long time, and I said, that’s the perfect material we’ve been looking for all along,” said Brian Trease, a mechanical engineer at JPL who was a co-author on the study.

    Although material scientists have been focusing on the 3-D printing of titanium alloys, the new research shows that complex shapes can be molded at low cost, while maintaining their performance, when using bulk metallic glasses.

    “You could start making robot bearings or artificial limbs out of these if you want,” said Eric Homer, assistant professor of mechanical engineering at Brigham Young and lead author of the study. “These materials are ideal for mechanisms where you’re looking for flexibility and high strength.”

    In the new study, the researchers modeled the performance of a number of compliant mechanisms and predicted that bulk metallic glasses would be the highest performing material in those applications, typically doubling the predicted performance of titanium. To verify the model, a bistable spring, a device that can lock in two different positions, was made out of both titanium and metallic glass and mechanically tested to show the benefits. The researchers then worked with two commercial companies to fabricate more than 30 identical versions of the new mechanism, utilizing a brand new injection-molding technology available in industry.

    “Demonstrating that these complex devices can be designed and prototyped using basic science is one thing. Taking the next step and working with industry to actually fabricate them will, we hope, bridge the gap between what we do in the lab and what we can deliver as actual spacecraft hardware,” said Hofmann.

    The researchers also demonstrated the assembly of various bulk metallic glass components into a larger mount used to rotate a mirror.

    “We hope that using these mechanisms in space will allow us to increase precision in our instruments and decrease their mass,” Hofmann said. “They may also prove useful for storing elastic energy that can be used in space to deploy components without having to use motors.”

    Hofmann and co-authors from JPL and Brigham Young envision applications for aerospace and defense. Sporting goods such as golf clubs could be made of these materials, and so could medical implants that need to flex in the body such as hip replacement components. On spacecraft, metallic glasses could be used for tilting and positioning mirrors, or for structures that open antennas or shoot cube satellites out of spacecraft. If metallic glasses can be made en mass like plastics, but retain robust properties of metals, they could also be used for a wide assortment of consumer devices, from laptops to robots to cars.

    See the full article here.

    campus

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

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  • richardmitnick 2:17 pm on September 26, 2014 Permalink | Reply
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    From NASA/JPL at Caltech: “Cold Atom Laboratory Chills Atoms to New Lows” 

    JPL

    September 26, 2014
    Elizabeth Landau
    Jet Propulsion Laboratory, Pasadena, Calif.
    818-354-6425
    elizabeth.landau@jpl.nasa.gov

    NASA’s Cold Atom Laboratory (CAL) mission has succeeded in producing a state of matter known as a Bose-Einstein condensate, a key breakthrough for the instrument leading up to its debut on the International Space Station in late 2016.

    NASA Cold Atom Laboratory
    >NASA’s Cold Atom Laboratory

    A Bose-Einstein condensate (BEC) is a collection of atoms in a dilute gas that have been lowered to extremely cold temperatures and all occupy the same quantum state, in which all of the atoms have the same energy levels. At a critical temperature, atoms begin to coalesce, overlap and become synchronized like dancers in a chorus line. The resulting condensate is a new state of matter that behaves like a giant — by atomic standards — wave.

    “It’s official. CAL’s ground testbed is the coolest spot at NASA’s Jet Propulsion Laboratory at 200 nano-Kelvin [200 billionths of 1 Kelvin], “said Cold Atom Laboratory Project Scientist Rob Thompson at JPL in Pasadena, California. “Achieving Bose-Einstein condensation in our prototype hardware is a crucial step for the mission.”

    Although these quantum gases had been created before elsewhere on Earth, the Cold Atom Laboratory will explore the condensates in an entirely new regime: The microgravity environment of the space station. It will enable groundbreaking research in temperatures colder than any found on Earth.

    CAL will be a facility for studying ultra-cold quantum gases on the space station. In the station’s microgravity environment, interaction times and temperatures as low as one picokelvin (one trillionth of one Kelvin, or 293 trillion times below room temperature) should be achievable. That’s colder than anything known in nature, and the experiments with CAL could potentially create the coldest matter ever observed in the universe. These breakthrough temperatures unlock the potential to observe new quantum phenomena and test some of the most fundamental laws of physics.

    First observed in 1995, Bose-Einstein condensation has been one of the “hottest” topics in physics ever since. The condensates are different from normal gases; they represent a distinct state of matter that starts to form typically below a millionth of a degree above absolute zero, the temperature at which atoms have the least energy and are close to motionless. Familiar concepts of “solid,” “liquid” and “gas” no longer apply at such cold temperatures; instead, atoms do bizarre things governed by quantum mechanics, such as behaving as waves and particles at the same time.

    Cold Atom Laboratory researchers used lasers to optically cool rubidium atoms to temperatures almost a million times colder than that of the depths of space. The atoms were then magnetically trapped, and radio waves were used to cool the atoms 100 times lower. The radiofrequency radiation acts like a knife, slicing away the hottest atoms from the trap so that only the coldest remain.

    The research is at the point where this process can reliably create a Bose-Einstein condensate in just seconds.

    “This was a tremendous accomplishment for the CAL team. It confirms the fidelity of the instrument system design and provides us a facility to perform science and hardware verifications before we get to the space station,” said CAL Project Manager Anita Sengupta of JPL.

    While so far, the Cold Atom Laboratory researchers have created Bose-Einstein condensates with rubidium atoms, eventually they will also add in potassium. The behavior of two condensates mixing together will be fascinating for physicists to observe, especially in space.

    Besides merely creating Bose-Einstein condensates, CAL provides a suite of tools to manipulate and probe these quantum gases in a variety of ways. It has a unique role as a facility for the atomic, molecular and optical physics community to study cold atomic physics in microgravity, said David Aveline of JPL, CAL ground testbed lead.

    “Instead of a state-of-the-art telescope looking outward into the cosmos, CAL will look inward, exploring physics at the atomic scale,” Aveline said.

    JPL is developing the Cold Atom Laboratory sponsored by the International Space Station Program at NASA’s Johnson Space Center in Houston.

    The Space Life and Physical Sciences Division of NASA’s Human Exploration and Operations Mission Directorate at NASA Headquarters in Washington manages the Fundamental Physics Program.

    See the full article here.

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

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  • richardmitnick 6:59 pm on September 7, 2014 Permalink | Reply
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    From NASA/JPL at Caltech- “NASA Instrument on Rosetta: First Science Results” 

    JPL

    September 04, 2014
    DC Agle
    Jet Propulsion Laboratory, Pasadena, Calif.
    818-393-9011
    agle@jpl.nasa.gov

    Dwayne Brown
    NASA Headquarters, Washington
    202-358-1726
    dwayne.c.brown@nasa.gov

    Maria Martinez
    Southwest Research Institute, Boulder, Colo.
    210-522-3305
    mmartinez@swri.org

    Markus Bauer
    European Space Agency, Noordwijk, Netherlands
    011-31-71-565-6799
    markus.bauer@esa.int

    A NASA instrument aboard the European Space Agency’s (ESA’s) Rosetta orbiter has successfully made its first delivery of science data from comet 67P/Churyumov-Gerasimenko.

    ESA Rosetta spacecraft
    ESA/Rosetta

    The instrument, named Alice, began mapping the comet’s surface last month, recording the first far-ultraviolet light spectra of the comet’s surface. From the data, the Alice team discovered the comet is unusually dark — darker than charcoal-black — when viewed in ultraviolet wavelengths. Alice also detected both hydrogen and oxygen in the comet’s coma, or atmosphere.

    alice
    ALICE on Rosetta

    Rosetta scientists also discovered the comet’s surface so far shows no large water-ice patches. The team expected to see ice patches on the comet’s surface because it is too far away for the sun’s warmth to turn its water into vapor.

    “We’re a bit surprised at just how unreflective the comet’s surface is and how little evidence of exposed water-ice it shows,” said Alan Stern, Alice principal investigator at the Southwest Research Institute in Boulder, Colorado.

    Alice is probing the origin, composition and workings of comet 67P/Churyumov-Gerasimenko, to gather sensitive, high-resolution insights that cannot be obtained by either ground-based or Earth-orbiting observation. It has more than 1,000 times the data-gathering capability of instruments flown a generation ago, yet it weighs less than nine pounds (four kilograms) and draws just four watts of power. The instrument is one of two full instruments on board Rosetta that are funded by NASA. The agency also provided portions of two other instrument suites.

    Other U.S. contributions aboard the spacecraft are the Microwave Instrument for Rosetta Orbiter (MIRO), the Ion and Electron Sensor (IES), part of the Rosetta Plasma Consortium Suite, and the Double Focusing Mass Spectrometer (DFMS) electronics package for the Rosetta Orbiter Spectrometer for Ion Neutral Analysis (ROSINA). They are part of a suite of 11 total science instruments aboard Rosetta.

    MIRO is designed to provide data on how gas and dust leave the surface of the nucleus to form the coma and tail that gives comets their intrinsic beauty. IES is part of a suite of five instruments to analyze the plasma environment of the comet, particularly the coma.

    To obtain the orbital velocity necessary to reach its comet target, the Rosetta spacecraft took advantage of four gravity assists (three from Earth, one from Mars) and an almost three-year period of deep space hibernation, waking up in January 2014 in time to prepare for its rendezvous with 67P/Churyumov-Gerasimenko.

    Rosetta also carries a lander, Philae, which will drop to the comet’s surface in November 2014.

    philae
    Philae

    The comet observations will help scientists learn more about the origin and evolution of our solar system and the role comets may have played in providing 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 in Cologne; Max Planck Institute for Solar System Research in Göttingen; French National Space Agency in Paris; and the Italian Space Agency in Rome.

    NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, manages the U.S. contribution to the Rosetta mission for the agency’s Science Mission Directorate in Washington. JPL also built the MIRO instrument and hosts its principal investigator, Samuel Gulkis. The Southwest Research Institute, located in San Antonio and Boulder, developed Rosetta’s IES and Alice instruments and hosts their principal investigators, James Burch (IES) and Alan Stern (Alice).

    See the full article here.

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

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  • richardmitnick 5:05 am on June 11, 2014 Permalink | Reply
    Tags: , , , , , NASA JPL   

    From NASA/JPL at Caltech: “NASA Instruments on Rosetta Start Comet Science” 

    JPL

    June 10, 2014
    DC Agle
    Jet Propulsion Laboratory, Pasadena, Calif.
    818-393-9011
    agle@jpl.nasa.gov

    Dwayne Brown
    Headquarters, Washington
    202-358-1726
    dwayne.c.brown@nasa.gov

    Markus Bauer
    European Space Agency, Noordwijk, Netherlands
    011-31-71-565-6799
    markus.bauer@esa.int

    Three NASA science instruments aboard the European Space Agency’s (ESA) Rosetta spacecraft, which is set to become the first to orbit a comet and land a probe on its nucleus, are beginning observations and sending science data back to Earth.

    rosetta

    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 objective is to arrive at comet 67P/Churyumov-Gerasimenko in August to study the celestial object up close in unprecedented detail and prepare for landing a probe on the comet’s nucleus in November.

    Rosetta’s lander will obtain the first images taken from a comet’s surface and will provide the first analysis of a comet’s 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.

    “We are happy to be seeing some real zeroes and ones coming down from our instruments, and cannot wait to figure out what they are telling us,” said Claudia Alexander, Rosetta’s U.S. project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California. “Never before has a spacecraft pulled up and parked next to a comet. That is what Rosetta will do, and we are delighted to play a part in such a historic mission of exploration.”

    Rosetta currently is approaching the main asteroid belt located between Jupiter and Mars. The spacecraft is still about 300,000 miles (500,000 kilometers) from the comet, but in August the instruments will begin to map its surface.

    The three U.S. instruments aboard the spacecraft are the Microwave Instrument for Rosetta Orbiter (MIRO), an ultraviolet spectrometer called Alice, and the Ion and Electron Sensor (IES). They are part of a suite of 11 science instruments aboard the Rosetta orbiter.

    miro

    alice
    ALICE

    ies
    IES

    MIRO is designed to provide data on how gas and dust leave the surface of the nucleus to form the coma and tail that gives comets their intrinsic beauty. Studying the surface temperature and evolution of the coma and tail provides information on how the comet evolves as it approaches and leaves the vicinity of the sun.

    Alice will analyze gases in the comet’s coma, which is the bright envelope of gas around the nucleus of the comet developed as a comet approaches the sun. Alice also will measure the rate at which the comet produces water, carbon monoxide and carbon dioxide. These measurements will provide valuable information about the surface composition of the nucleus.

    The instrument also will measure the amount of argon present, an important clue about the temperature of the solar system at the time the comet’s nucleus originally formed more than 4.6 billion years ago.

    IES is part of a suite of five instruments to analyze the plasma environment of the comet, particularly the coma. The instrument will measure the charged particles in the sun’s outer atmosphere, or solar wind, as they interact with the gas flowing out from the comet while Rosetta is drawing nearer to the comet’s nucleus.

    NASA also provided part of the electronics package for the Double Focusing Mass Spectrometer, which is part of the Swiss-built Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) instrument. ROSINA will be the first instrument in space with sufficient resolution to be able to distinguish between molecular nitrogen and carbon monoxide, two molecules with approximately the same mass. Clear identification of nitrogen will help scientists understand conditions at the time the solar system was formed.

    U.S. scientists are partnering on several non-U.S. instruments and are involved in seven of the mission’s 21 instrument collaborations. NASA’s Deep Space Network is supporting ESA’s Ground Station Network for spacecraft tracking and navigation.

    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, Gottigen; French National Space Agency, Paris; and the Italian Space Agency, Rome. JPL, a division of the California Institute of Technology, Pasadena, manages the U.S. contribution of the Rosetta mission for NASA’s Science Mission Directorate in Washington. JPL also built the MIRO and hosts its principal investigator, Samuel Gulkis. The Southwest Research Institute (San Antonio and Boulder), developed the Rosetta orbiter’s IES and Alice instruments, and hosts their principal investigators, James Burch (IES) and Alan Stern (Alice).

    See the full article here.

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

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  • richardmitnick 2:56 pm on May 5, 2014 Permalink | Reply
    Tags: , Biosphere, NASA JPL   

    From NASA/JPL at Caltech: “How Does Your Garden Glow? NASA’s OCO-2 Seeks Answer 

    JPL

    May 05, 2014
    Laurie J. Schmidt

    Science is full of serendipity — moments when discoveries happen by chance or accident while researchers are looking for something else. For example, penicillin was identified when a blue-green mold grew on a Petri dish that had been left open by mistake.

    Now, satellite instruments have given climate researchers at NASA and other research institutions an unexpected global view from space of a nearly invisible fluorescent glow that sheds new light on the productivity of vegetation on land. Previously, global views of this glow from chlorophyll were only possible over Earth’s ocean, using NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS) instruments on NASA’s Terra and Aqua spacecraft.

    NASA MODIS
    NASA/MODIS

    NASA Terra satellite
    NASA/TERRA

    NASA Aqua satellite
    NASA/AQUA

    When the Japanese Greenhouse gases Observing SATellite (GOSAT), known as “IBUKI” in Japan, launched into orbit in 2009, its primary mission was to measure levels of carbon dioxide and methane, two major heat-trapping greenhouse gases in Earth’s atmosphere. However, NASA researchers, in collaboration with Japanese and other international colleagues, found another treasure hidden in the data: fluorescence from chlorophyll contained within plants. Although scientists have measured fluorescence in laboratory settings and ground-based field experiments for decades, these new satellite data now provide the ability to monitor what is known as solar-induced chlorophyll fluorescence on a global scale, opening up a world of potential new applications for studying vegetation on land.

    GOSAT JE
    GOSAT

    A “signature” of photosynthesis, solar-induced chlorophyll fluorescence is an indicator of the process by which plants convert light from the sun into chemical energy. As chlorophyll molecules absorb incoming radiation, some of the light is dissipated as heat, and some radiation is re-emitted at longer wavelengths as fluorescence.

    Enter NASA’s Orbiting Carbon Observatory-2 (OCO-2). Researchers who study the interaction of plants, carbon and climate are eagerly awaiting fluorescence data from the OCO-2 satellite mission, scheduled to launch in July 2014. The instrument aboard OCO-2 will make precise measurements of carbon dioxide in the atmosphere, recording 24 observations a second versus GOSAT’s single observation every four seconds, resulting in almost 100 times more observations of both carbon dioxide and fluorescence than GOSAT.

    NASA OCO satellite
    NASA/OCO-2

    “Data from OCO-2 will extend the GOSAT time series and allow us to observe large-scale changes to photosynthesis in a new way,” said David Schimel, lead scientist for the Carbon and Ecosystems research program at NASA’s Jet Propulsion Laboratory, Pasadena, Calif., which manages the OCO-2 mission for NASA. “The fluorescence data may turn out to be a unique and very complementary data set of the OCO-2 mission.”

    “OCO-2′s fluorescence data, when combined with the observatory’s atmospheric carbon dioxide measurements, will increase the value of the OCO-2 mission to NASA, the United States and world,” said Ralph Basilio, OCO-2 project manager at JPL.

    Turning the Sun Off

    Being able to see fluorescence from space allows scientists to estimate photosynthesis rates over vast scales, gleaning insights into vital processes that affect humans and other living things on Earth. “The rate of photosynthesis is critical because it’s the process that drives the absorption of carbon from the atmosphere and agricultural [food] production,” said Joseph Berry, a researcher in the Department of Global Ecology at Carnegie Institution for Science in Stanford, Calif.

    Measuring the fluorescent “glow” may sound simple, but the tiny signal is overpowered by reflected sunlight. “Imagine that you’re in your child’s bedroom and they have a bunch of glow-in-the-dark stars on the ceiling,” Schimel said. “Then you turn the lights on. The stars are still glowing, but looking for that glow with the lights on is like looking for fluorescence amidst the reflected sunlight.” Retrieving the fluorescence data requires disentangling sunlight that is reflected by plants from the light given off by them — in other words, figuring out a way to “turn the sun off.”

    Researchers found that by tuning GOSAT’s spectrometer (an instrument that can measure different parts of the spectrum of light) to look at very narrow channels, they could see parts of the spectrum where there was fluorescence but less reflected solar radiation. “It’s as if you had put on a pair of glasses that filtered out the radiation in your child’s room except for that glow from the stars,” said Schimel.

    Scientists are excited about the new measurement because it will give them better insight into how Earth’s plants are taking up carbon dioxide. According to the Global Carbon Project, a non-governmental organization devoted to developing a complete picture of the carbon cycle, our burning of fossil fuels on Earth had produced nearly 35 billion tons of carbon dioxide by 2011. This is almost 5 tons of carbon dioxide for every one of Earth’s seven billion inhabitants.

    About half of that carbon dioxide remains in the atmosphere. The other half is dissolved in the ocean or taken up by Earth’s biosphere (living organisms on land and in the ocean), where it is tucked away in carbon reservoirs or “sinks.” These sinks are shielding us from the full effect of our emissions.

    Plants in a High-Carbon World

    “Everybody that’s using fossil fuels right now is being subsidized by the biosphere,” said Berry. “But one of the key unknowns is — what’s going to be happening in the long term? Is it going to continue to subsidize us?”

    bis
    A false-color composite of global oceanic and terrestrial photoautotroph abundance, from September 1997 to August 2000. Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center and ORBIMAGE.

    The future of Earth’s plants depends largely on one of the carbon cycle’s key ingredients: water. Plants need water to carry out photosynthesis. When their water supply runs low, such as during times of drought, photosynthesis slows down.

    For the past quarter century, satellite instruments such as MODIS and the Advanced Very High Resolution Radiometer (AVHRR) on NOAA polar-orbiting satellites have enabled researchers to monitor plant health and productivity by measuring the amount of “greenness,” which shows how much leaf material is exposed to sunlight. The drawback of using the greenness index, however, is that greenness doesn’t immediately respond to stresses — water stress for example — that reduce photosynthesis and productivity.

    NOAA with AVHRR
    NOAA satellite with AVHRR

    “Plants can be green, but not active,” said JPL research scientist Christian Frankenberg, also a member of the OCO-2 science team. “Imagine an evergreen needle-leaf forest at high elevation in winter. The trees are still green, but they’re not photosynthesizing.”

    Solar-induced fluorescence data would tell you straight away that something had happened, explains Schimel, but greenness doesn’t tell you until the plants are already drooping and maybe dead.

    About 30 percent of the photosynthesis that occurs in Earth’s land regions takes place in the tropical rainforest of the Amazon, which encompasses about 2.7 million square miles (7 million square kilometers) of South America. The Amazon is home to more than half of Earth’s terrestrial biomass and tropical forest area — making it one of the two most important land regions for carbon storage (the other being the Arctic, where carbon is stored in the soil).

    Recent studies in the Amazon using fluorescence measurements have examined how photosynthesis rates change during wet and dry seasons. Most of the results show that during the dry season, photosynthesis slows down. According to Berry, when the air is dry and hot, it makes sense for plants to conserve water by closing their stomates (pores). “During the dry season when it would cost the plants a lot of water, photosynthesis is dialed down and the forest becomes less active,” he said.

    In 2005 and 2010, the Amazon basin experienced the type of droughts that historically have happened only once in a century. Greenness measurements indicated widespread die-off of trees and major changes to the forest canopy (treetops) after the droughts, but fluorescence data from GOSAT exposed even milder water stress in the dry season of normal years. “There is the potential that as climate change proceeds, these droughts will become more severe. The areas that support tropical rainforest could decrease,” said Berry. Less tropical forest means less carbon absorbed from the air.

    In addition, as trees decay, they release carbon dioxide back into the atmosphere, creating a scenario whereby the biosphere potentially becomes a source of carbon rather than a sink. “If there is a dieback of the tropical rainforest, that might add to the effect of fossil fuel carbon dioxide on climate change,” said Frankenberg.

    Because photosynthesis is one of the key processes involved in the carbon cycle, and because the carbon cycle plays an important role in climate, better fluorescence information could help resolve some uncertainties about the uptake of carbon dioxide by plants in climate models. “We think fluorescence is going to help carbon cycle models get the right answer,” said Berry. “If you don’t have the models right, how can you get the rest of it right?”

    “We really don’t understand the quantitative relationship between climate and photosynthesis very well, because we’ve only been able to study it at very small scales,” said Schimel. “Measuring plant fluorescence from space may be an important addition to the set of techniques available to us.”

    See the full article here.

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

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  • richardmitnick 8:24 am on May 2, 2014 Permalink | Reply
    Tags: , , , , , NASA JPL   

    From NASA/JPL at Caltech: “Ganymede May Harbor ‘Club Sandwich’ of Oceans and Ice” 

    NASA/JPL at Caltech

    May 01, 2014
    Whitney Clavin
    Jet Propulsion Laboratory, Pasadena, Calif.
    818-354-4673
    whitney.clavin@jpl.nasa.gov

    The largest moon in our solar system, a companion to Jupiter named Ganymede, might have ice and oceans stacked up in several layers like a club sandwich, according to new NASA-funded research that models the moon’s makeup.

    gan
    This artist’s concept of Jupiter’s moon Ganymede, the largest moon in the solar system, illustrates the “club sandwich” model of its interior oceans. Image credit: NASA/JPL-Caltech

    Previously, the moon was thought to harbor a thick ocean sandwiched between just two layers of ice, one on top and one on bottom.

    “Ganymede’s ocean might be organized like a Dagwood sandwich,” said Steve Vance of NASA’s Jet Propulsion Laboratory in Pasadena, Calif., explaining the moon’s resemblance to the “Blondie” cartoon character’s multi-tiered sandwiches. The study, led by Vance, provides new theoretical evidence for the team’s “club sandwich” model, first proposed last year. The research appears in the journal Planetary and Space Science.

    The results support the idea that primitive life might have possibly arisen on the icy moon. Scientists say that places where water and rock interact are important for the development of life; for example, it’s possible life began on Earth in bubbling vents on our sea floor. Prior to the new study, Ganymede’s rocky sea bottom was thought to be coated with ice, not liquid — a problem for the emergence of life. The “club sandwich” findings suggest otherwise: the first layer on top of the rocky core might be salty water.

    “This is good news for Ganymede,” said Vance. “Its ocean is huge, with enormous pressures, so it was thought that dense ice had to form at the bottom of the ocean. When we added salts to our models, we came up with liquids dense enough to sink to the sea floor.”

    NASA scientists first suspected an ocean in Ganymede in the 1970s, based on models of the large moon, which is bigger than Mercury. In the 1990s, NASA’s Galileo mission flew by Ganymede, confirming the moon’s ocean, and showing it extends to depths of hundreds of miles. The spacecraft also found evidence for salty seas, likely containing the salt magnesium sulfate.

    NASA Galileo spacecraft
    NASA/Galileo

    Previous models of Ganymede’s oceans assumed that salt didn’t change the properties of liquid very much with pressure. Vance and his team showed, through laboratory experiments, how much salt really increases the density of liquids under the extreme conditions inside Ganymede and similar moons. It may seem strange that salt can make the ocean denser, but you can see for yourself how this works by adding plain old table salt to a glass of water. Rather than increasing in volume, the liquid shrinks and becomes denser. This is because the salt ions attract water molecules.

    The models get more complicated when the different forms of ice are taken into account. The ice that floats in your drinks is called “Ice I.” It’s the least dense form of ice and lighter than water. But at high pressures, like those in crushingly deep oceans like Ganymede’s, the ice crystal structures become more compact. “It’s like finding a better arrangement of shoes in your luggage — the ice molecules become packed together more tightly,” said Vance. The ice can become so dense that it is heavier than water and falls to the bottom of the sea. The densest and heaviest ice thought to persist in Ganymede is called “Ice VI.”

    By modeling these processes using computers, the team came up with an ocean sandwiched between up to three ice layers, in addition to the rocky seafloor. The lightest ice is on top, and the saltiest liquid is heavy enough to sink to the bottom. What’s more, the results demonstrate a possible bizarre phenomenon that causes the oceans to “snow upwards.” As the oceans churn and cold plumes snake around, ice in the uppermost ocean layer, called “Ice III,” could form in the seawater. When ice forms, salts precipitate out. The heavier salts would thus fall downward, and the lighter ice, or “snow,” would float upward. This “snow” melts again before reaching the top of the ocean, possibly leaving slush in the middle of the moon sandwich.

    “We don’t know how long the Dagwood-sandwich structure would exist,” said Christophe Sotin of JPL. “This structure represents a stable state, but various factors could mean the moon doesn’t reach this stable state.

    Sotin and Vance are both members of the Icy Worlds team at JPL, part of the multi-institutional NASA Astrobiology Institute based at the Ames Research Center in Moffett Field, Calif.

    The results can be applied to exoplanets too, planets that circle stars beyond our sun. Some super-Earths, rocky planets more massive than Earth, have been proposed as “water worlds” covered in oceans. Could they have life? Vance and his team think laboratory experiments and more detailed modeling of exotic oceans might help find answers.

    Ganymede is one of five moons in our solar system thought to support vast oceans beneath icy crusts. The other moons are Jupiter’s Europa and Callisto and Saturn’s Titan and Enceladus. The European Space Agency is developing a space mission, called JUpiter ICy moons Explorer or JUICE, to visit Europa, Callisto and Ganymede in the 2030s. NASA and JPL are contributing to three instruments on the mission, which is scheduled to launch in 2022 (see http://www.jpl.nasa.gov/news/news.php?release=2013-069).

    ESA JUICE
    ESA/JUICE

    Other authors of the study are Mathieu Bouffard of Ecole Normale Supérieure de Lyon, France, and Mathieu Choukroun, also of JPL and the Icy World team of the NASA Astrobiology Institute. JPL is managed by the California Institute of Technology in Pasadena for NASA.

    See the full article here.

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

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