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  • richardmitnick 9:26 am on May 14, 2019 Permalink | Reply
    Tags: As the twin GRACE satellites orbited Earth one closely following the other the changes in mass below changed the distance between the two satellites very slightly., GRACE and its successor GRACE Follow-On were designed to measure changes in gravitational pull that result from changes in mass on Earth., NASA JPL - Caltech, NASA/German Gravity Recovery and Climate Experiment (GRACE) spacecraft, NASA/German Research Centre for Geosciences (GFZ) GRACE Follow-On spacecraft, The record of these changes was analyzed to create monthly global maps of changes and redistribution of Earth's mass near the surface.   

    From JPL-Caltech: “NASA’s GRACE: What We’ve Learned from Water in Motion” 

    NASA JPL Banner

    From JPL-Caltech

    May 13, 2019

    News Media Contact
    Esprit Smith
    Jet Propulsion Laboratory, Pasadena, California
    818-354-4269
    Esprit.Smith@jpl.nasa.gov

    Written by Carol Rasmussen
    NASA’s Earth Science News Team

    1
    Twin U.S./German Gravity Recovery and Climate Experiment (GRACE). Image credit: NASA/JPL-Caltech

    When you hear news about ice loss from Greenland or Antarctica, an aquifer in California that is getting depleted, or a new explanation for a wobble in Earth’s rotation, you might not realize that all these findings may rely on data from one single mission: the U.S.-German Gravity Recovery and Climate Experiment (GRACE). GRACE data, collected from 2002 to 2017 while the mission was active, are still being used to improve our understanding of water in motion and its sometimes surprising effects on our planet. A new paper brings together newly calculated and existing summaries of the major results GRACE has generated, showcasing the breadth of topics the mission has illuminated over the years.

    “Water is an important sign of the health of the planet,” said Michael Watkins, the original GRACE project scientist and now director of NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California. “But water is hard to track in some forms – for example, polar ice or water stored deep underground. We need to understand those components as well as we understand water in its more easily assessable forms around the globe. That’s what GRACE has enabled us to do.” Scientists have used this increased knowledge of how water moves and is stored on Earth to understand global climate and how it is changing.

    Byron Tapley, GRACE’s original principal investigator and the motivating force behind the mission (now retired from the University of Texas at Austin), is the lead author of the new paper. Titled Contributions of GRACE to Understanding Climate Change and published in the journal Nature Climate Change, it summarizes the latest results and new insights GRACE has enabled up to the present. The review, which covers aspects of the GRACE measurement technique, scientific breakthroughs and the relevance for climate service applications, was written by a distinguished team of GRACE experts. Most authors contributed to the GRACE mission even before it launched and have done groundbreaking work with its data.

    Paper authors:
    Byron D. Tapley, Michael M. Watkins, Frank Flechtner, Christoph Reigber, Srinivas Bettadpur, Matthew Rodell, Ingo Sasgen, James S. Famiglietti, Felix W. Landerer, Don P. Chambers, John T. Reager, Alex S. Gardner, Himanshu Save, Erik R. Ivins, Sean C. Swenson, Carmen Boening, Christoph Dahle, David N. Wiese, Henryk Dobslaw, Mark E. Tamisiea & Isabella Velicogna

    ________________________________________________________
    How Measuring Gravity Reveals Moving Water

    GRACE and its successor, GRACE Follow-On, were designed to measure changes in gravitational pull that result from changes in mass on Earth. More than 99 percent of Earth’s mean gravitational pull does not change from one month to the next. That’s because it comes from the mass of the solid Earth itself – its surface and interior – and that rarely moves, or moves very slowly. Water, on the other hand, moves continually nearly everywhere: Snow falls, ocean currents flow, ice melts and so on. As the twin GRACE satellites orbited Earth, one closely following the other, the changes in mass below changed the distance between the two satellites very slightly. The record of these changes was analyzed to create monthly global maps of changes and redistribution of Earth’s mass near the surface.
    ________________________________________________________

    “It was a challenge to write a representative eight-page review of GRACE achievements, which have been documented in over 3,000 peer-reviewed publications,” said Ingo Sasgen, GRACE scientist at the Alfred Wegener Institute’s Helmholtz Center for Polar and Marine Research in Bremerhaven, Germany, who coordinated the new paper. “We wanted to convey how unique the GRACE mission really was and how important its data are for us to understand how climate change affects water stored in the ocean, the ice and on the continents.” Here are a few examples.

    Greenland and Antarctica. The paper updates previous studies to report that during the lifetime of the GRACE mission, Greenland lost 258 gigatons of ice per year, with the amount varying by more than 50% from year to year, to a large extent in response to temperatures during the summer months. “The Arctic is warming about twice as fast as the global average, with ice-mass loss and sea level rise being major consequences,” said Sasgen. “With GRACE we were able to budget each month the mass loss of glaciers and ice sheets around the world. These data have dramatically improved our understanding of the processes at play in these remote areas and their sensitivity to climate change.” Antarctica lost 137 gigatons per year on average, but the annual rate of loss varied by more than 200%, mainly due to fluctuations in snowfall. GRACE also found that these large fluctuations mostly occur in West Antarctica and correlate well with El Niño events, which affect how much precipitation reaches the continent.

    Changes in water storage on land. GRACE has revealed that less water is now being stored naturally in mid-latitude land regions (that is, these regions are getting less precipitation and are becoming drier) and more is being stored in high- and low-latitude regions (that is, those regions are getting wetter). Climate models have long predicted that global climate change will bring about this trend, so the observations provide an important early confirmation of the models.

    Sea level rise. The sea level rose more than 1.5 inches (3.7 centimeters) per decade on average over the globe from 2005 to 2016. There are two main causes for this change: runoff from melting ice sheets and glaciers, and expansion of the ocean water itself as it warms. Besides monitoring changes in the ice sheets and glaciers, GRACE could detect how much sea level rise was due to water formerly locked in ice on land being added to the ocean. The data show that this source increased throughout the mission and is currently responsible for about two-thirds of sea level rise.

    “GRACE provided a paradigm shift in our view of how the oceans, atmosphere and land surface components interact,” said Tapley. “As an example, GRACE showed that the water leaving the polar ice caps is equal to the increase in water mass in the oceans, giving confirmation of this important measurement’s use in assessing ocean heat storage.”

    Besides its value to research, Tapley pointed out, “GRACE is also an important asset for assessing the state of freshwater and assisting in managing it.” To improve flood forecasts for Europe, the European Gravity Service for Improved Emergency Management uses GRACE data to look at soil saturation levels weeks before flood season. Researchers have found that knowledge of unusually high levels of underground water storage can increase the lead time on warnings of peak river flooding by up to six weeks. In situations where freshwater is scarce, GRACE data support the U.S. Drought Monitor, which tracks drought across the United States and its territories and is widely used by managers at federal and state levels.

    GRACE’s value to the scientific community was recognized within its first two years of operation, and the community strongly recommended that the mission be continued without major data gaps. To accomplish that, NASA and the German Research Centre for Geosciences (GFZ) launched a successor, GRACE Follow-On, in May 2018. GRACE-FO has completed all of its checkout phases and will soon begin releasing monthly maps of mass changes on Earth. “GRACE-FO allows us to continue the revolutionary legacy of GRACE,” Watkins said. “There are sure to be more unexpected and innovative findings ahead.”

    GRACE was implemented as a joint mission of NASA and the German Aerospace Center. GRACE was the first principal-investigator-led mission implemented under the Earth System Pathfinder Program. The implementing team included the University of Texas at Austin, JPL and the GFZ. JPL managed the implementation and operations for NASA’s Science Mission Directorate in Washington. Caltech in Pasadena manages JPL for NASA.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    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, 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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    NASA image

     
  • richardmitnick 12:16 pm on May 9, 2019 Permalink | Reply
    Tags: "New Clues About How Ancient Galaxies Lit up the Universe", , , , , , NASA JPL - Caltech, , Observations came from the GREATS survey short for GOODS Re-ionization Era wide-Area Treasury from Spitzer.   

    From JPL-Caltech: “New Clues About How Ancient Galaxies Lit up the Universe” 

    NASA JPL Banner

    From JPL-Caltech

    May 8, 2019
    Calla Cofield
    Jet Propulsion Laboratory, Pasadena, Calif.
    626-808-2469
    calla.e.cofield@jpl.nasa.gov

    1
    This deep-field view of the sky, taken by NASA’s Spitzer Space Telescope, is dominated by galaxies – including some very faint, very distant ones – circled in red. The bottom right inset shows one of those distant galaxies, made visible thanks to a long-duration observation by Spitzer. The wide-field view also includes data from NASA’s Hubble Space Telescope. The Spitzer observations came from the GREATS survey, short for GOODS Re-ionization Era wide-Area Treasury from Spitzer. GOODS is itself an acronym: Great Observatories Origins Deep Survey.

    NASA’s Spitzer Space Telescope has revealed that some of the universe’s earliest galaxies were brighter than expected. The excess light is a byproduct of the galaxies releasing incredibly high amounts of ionizing radiation. The finding offers clues to the cause of the Epoch of Reionization, a major cosmic event that transformed the universe from being mostly opaque to the brilliant starscape seen today.

    NASA/Spitzer Infrared Telescope

    In a new study [MNRAS], researchers report on observations of some of the first galaxies to form in the universe, less than 1 billion years after the big bang (or a little more than 13 billion years ago). The data show that in a few specific wavelengths of infrared light, the galaxies are considerably brighter than scientists anticipated. The study is the first to confirm this phenomenon for a large sampling of galaxies from this period, showing that these were not special cases of excessive brightness, but that even average galaxies present at that time were much brighter in these wavelengths than galaxies we see today.

    No one knows for sure when the first stars in our universe burst to life. But evidence suggests that between about 100 million and 200 million years after the big bang, the universe was filled mostly with neutral hydrogen gas that had perhaps just begun to coalesce into stars, which then began to form the first galaxies. By about 1 billion years after the big bang, the universe had become a sparkling firmament. Something else had changed, too: Electrons of the omnipresent neutral hydrogen gas had been stripped away in a process known as ionization. The Epoch of Reionization – the changeover from a universe full of neutral hydrogen to one filled with ionized hydrogen – is well documented.

    Before this universe-wide transformation, long-wavelength forms of light, such as radio waves and visible light, traversed the universe more or less unencumbered. But shorter wavelengths of light – including ultraviolet light, X-rays and gamma rays – were stopped short by neutral hydrogen atoms. These collisions would strip the neutral hydrogen atoms of their electrons, ionizing them.

    But what could have possibly produced enough ionizing radiation to affect all the hydrogen in the universe? Was it individual stars? Giant galaxies? If either were the culprit, those early cosmic colonizers would have been different than most modern stars and galaxies, which typically don’t release high amounts of ionizing radiation. Then again, perhaps something else entirely caused the event, such as quasars – galaxies with incredibly bright centers powered by huge amounts of material orbiting supermassive black holes.

    “It’s one of the biggest open questions in observational cosmology,” said Stephane De Barros, lead author of the study and a postdoctoral researcher at the University of Geneva in Switzerland. “We know it happened, but what caused it? These new findings could be a big clue.”

    Looking for Light

    To peer back in time to the era just before the Epoch of Reionization ended, Spitzer stared at two regions of the sky for more than 200 hours each, allowing the space telescope to collect light that had traveled for more than 13 billion years to reach us.

    Reionization era and first stars, Caltech

    As some of the longest science observations ever carried out by Spitzer, they were part of an observing campaign called GREATS, short for GOODS Re-ionization Era wide-Area Treasury from Spitzer. GOODS (itself an acronym: Great Observatories Origins Deep Survey) is another campaign that performed the first observations of some GREATS targets. The study, published in the Monthly Notices of the Royal Astronomical Society, also used archival data from NASA’s Hubble Space Telescope.

    Using these ultra-deep observations by Spitzer, the team of astronomers observed 135 distant galaxies and found that they were all particularly bright in two specific wavelengths of infrared light produced by ionizing radiation interacting with hydrogen and oxygen gases within the galaxies. This implies that these galaxies were dominated by young, massive stars composed mostly of hydrogen and helium. They contain very small amounts of “heavy” elements (like nitrogen, carbon and oxygen) compared to stars found in average modern galaxies.

    These stars were not the first stars to form in the universe (those would have been composed of hydrogen and helium only) but were still members of a very early generation of stars. The Epoch of Reionization wasn’t an instantaneous event, so while the new results are not enough to close the book on this cosmic event, they do provide new details about how the universe evolved at this time and how the transition played out.

    “We did not expect that Spitzer, with a mirror no larger than a Hula-Hoop, would be capable of seeing galaxies so close to the dawn of time,” said Michael Werner, Spitzer’s project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California. “But nature is full of surprises, and the unexpected brightness of these early galaxies, together with Spitzer’s superb performance, puts them within range of our small but powerful observatory.”

    NASA’s James Webb Space Telescope, set to launch in 2021, will study the universe in many of the same wavelengths observed by Spitzer. But where Spitzer’s primary mirror is only 85 centimeters (33.4 inches) in diameter, Webb’s is 6.5 meters (21 feet) – about 7.5 times larger – enabling Webb to study these galaxies in far greater detail. In fact, Webb will try to detect light from the first stars and galaxies in the universe. The new study shows that due to their brightness in those infrared wavelengths, the galaxies observed by Spitzer will be easier for Webb to study than previously thought.

    “These results by Spitzer are certainly another step in solving the mystery of cosmic reionization,” said Pascal Oesch, an assistant professor at the University of Geneva and a co-author on the study. “We now know that the physical conditions in these early galaxies were very different than in typical galaxies today. It will be the job of the James Webb Space Telescope to work out the detailed reasons why.”

    JPL manages the Spitzer Space Telescope mission for NASA’s Science Mission Directorate in Washington. Science operations are conducted at the Spitzer Science Center at Caltech in Pasadena. Space operations are based at Lockheed Martin Space Systems in Littleton, Colorado. Data are archived at the Infrared Science Archive housed at IPAC at Caltech. Caltech manages JPL for NASA.

    For more information on Spitzer, visit:

    http://www.nasa.gov/spitzer and http://www.spitzer.caltech.edu/

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    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, 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.

    Caltech Logo

    NASA image

     
  • richardmitnick 1:17 pm on May 6, 2019 Permalink | Reply
    Tags: , , , Before and after selfies reveals dust in the misson, , , , NASA JPL - Caltech, The same winds that blanket Mars with dust can also blow that dust away.   

    From JPL-Caltech: “For InSight, Dust Cleanings Will Yield New Science” 

    NASA JPL Banner

    From JPL-Caltech

    May 6, 2019

    Andrew Good
    Jet Propulsion Laboratory, Pasadena, Calif.
    818-393-2433
    andrew.c.good@jpl.nasa.gov

    1
    This is NASA InSight’s second full selfie on Mars. Since taking its first selfie, the lander has removed its heat probe and seismometer from its deck, placing them on the Martian surface; a thin coating of dust now covers the spacecraft as well. NASA/JPL-Caltech

    2
    InSight’s first selfie. NASA/JPL-Caltech

    This selfie is a mosaic made up of 14 images taken on March 15 and April 11 – the 106th and 133rd Martian days, or sols, of the mission – by InSight’s Instrument Deployment Camera, located on its robotic arm.

    InSight’s first selfie showed its instruments still on the deck. Now that they’re removed, the viewer can see the spacecraft’s air pressure sensor (white object in center), the tether box for its seismometer and the tether for its heat probe running across the deck. Also visible is its robotic arm and grapple.

    JPL manages InSight for NASA’s Science Mission Directorate. InSight is part of NASA’s Discovery Program, managed by the agency’s Marshall Space Flight Center in Huntsville, Alabama. Lockheed Martin Space in Denver built the InSight spacecraft, including its cruise stage and lander, and supports spacecraft operations for the mission.

    A number of European partners, including France’s Centre National d’Études Spatiales (CNES) and the German Aerospace Center (DLR), are supporting the InSight mission. CNES provided the Seismic Experiment for Interior Structure (SEIS) instrument to NASA, with the principal investigator at IPGP (Institut de Physique du Globe de Paris). Significant contributions for SEIS came from IPGP; the Max Planck Institute for Solar System Research (MPS) in Germany; the Swiss Federal Institute of Technology (ETH Zurich) in Switzerland; Imperial College London and Oxford University in the United Kingdom; and JPL. DLR provided the Heat Flow and Physical Properties Package (HP3) instrument, with significant contributions from the Space Research Center (CBK) of the Polish Academy of Sciences and Astronika in Poland. Spain’s Centro de Astrobiología (CAB) supplied the temperature and wind sensors.

    The same winds that blanket Mars with dust can also blow that dust away. Catastrophic dust storms have the potential to end a mission, as with NASA’s Opportunity rover. But far more often, passing winds cleared off the rover’s solar panels and gave it an energy boost. Those dust clearings allowed Opportunity and its sister rover, Spirit, to survive for years beyond their 90-day expiration dates.

    Dust clearings are also expected for Mars’ newest inhabitant, the InSight lander. Because of the spacecraft’s weather sensors, each clearing can provide crucial science data on these events, as well – and the mission already has a glimpse at that.

    On Feb. 1, the 65th Martian day, or sol, of the mission, InSight detected a passing wind vortex (also known as a dust devil if it picks up dust and becomes visible; InSight’s cameras didn’t catch the vortex in this case). At the same time, the lander’s two large solar panels experienced very small bumps in power – about 0.7% on one panel and 2.7% on the other – suggesting a tiny amount of dust was lifted.

    For more information about InSight, visit:

    https://mars.nasa.gov/insight/

    For more information about Mars, visit:

    https://mars.nasa.gov

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    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, 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.

    Caltech Logo

    NASA image

     
  • richardmitnick 1:23 pm on May 2, 2019 Permalink | Reply
    Tags: , , , , NASA JPL - Caltech, Near-Earth asteroid called 99942 Apophis   

    From JPL-Caltech: “Scientists Planning Now for Asteroid Flyby a Decade Away” 

    NASA JPL Banner

    From JPL-Caltech

    April 29, 2019

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

    JoAnna Wendel
    NASA Headquarters, Washington
    202-358-1003
    joanna.r.wendel@nasa.gov

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

    1
    This animation shows the distance between the Apophis asteroid and Earth at the time of the asteroid’s closest approach. The blue dots are the many man-made satellites that orbit our planet, and the pink represents the International Space Station.Credit: NASA/JPL-Caltech

    On April 13, 2029, a speck of light will streak across the sky, getting brighter and faster. At one point it will travel more than the width of the full Moon within a minute and it will get as bright as the stars in the Little Dipper. But it won’t be a satellite or an airplane – it will be a 1,100-foot-wide (340-meter-wide) near-Earth asteroid called 99942 Apophis that will cruise harmlessly by Earth, about 19,000 miles (31,000 kilometers) above the surface. That’s within the distance that some of our spacecraft that orbit Earth.

    3
    DAMIT model of Apophis generated from light curve. This assumes that all areas of the asteroid have a similar albedo and reflectivity. Astronomical Institute of the Charles University: Josef Ďurech, Vojtěch Sidorin

    The international asteroid research community couldn’t be more excited.

    This week at the 2019 Planetary Defense Conference in College Park, Maryland, scientists are gathering to discuss observation plans and science opportunities for the celestial event still a decade away. During a session on April 30, scientists will discuss everything from how to observe the event to hypothetical missions we could send out to the asteroid.

    “The Apophis close approach in 2029 will be an incredible opportunity for science,” said Marina Brozović, a radar scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California, who works on radar observations of near-Earth objects (NEOs). “We’ll observe the asteroid with both optical and radar telescopes. With radar observations, we might be able to see surface details that are only a few meters in size.”

    It’s rare for an asteroid of this size to pass by Earth so close. Although scientists have spotted small asteroids, on the order of 5-10 meters, flying by Earth at a similar distance, asteroids the size of Apophis are far fewer in number and so do not pass this close to Earth as often.

    The asteroid, looking like a moving star-like point of light, will first become visible to the naked eye in the night sky over the Southern Hemisphere, flying above Earth from the east coast to the west coast of Australia. It will be mid-morning on the East Coast of the United States when Apophis is above Australia. It will then cross the Indian Ocean, and by the afternoon in the eastern U.S. it will have crossed the equator, still moving west, above Africa. At closest approach, just before 6 p.m. EDT, Apophis will be over the Atlantic Ocean – and it will move so fast that it will cross the Atlantic in just an hour. By 7 p.m. EDT, the asteroid will have crossed over the United States.

    A team of astronomers at the Kitt Peak National Observatory discovered Apophis in June 2004.

    Kitt Peak National Observatory of the Quinlan Mountains in the Arizona-Sonoran Desert on the Tohono O’odham Nation, 88 kilometers 55 mi west-southwest of Tucson, Arizona, Altitude 2,096 m (6,877 ft)

    The astronomers were only able to detect the asteroid for two days before technical and weather issues prevented further observations. Luckily, another team rediscovered the asteroid at the Siding Spring Survey in Australia later that year.

    Siding Spring Mountain with Anglo-Australian Telescope dome visible near centre of image at an altitude of 1,165 m (3,822 ft)

    The observations caused quite a stir – initial orbital calculations revealed that the asteroid had a 2.7% chance of impacting Earth in 2029. Fortunately, additional observations completely ruled out that possibility.

    Since its discovery, optical and radar telescopes have tracked Apophis as it continues on its orbit around the Sun, so we know its future trajectory quite well. Current calculations show that Apophis still has a small chance of impacting Earth, less than 1 in 100,000 many decades from now, but future measurements of its position can be expected to rule out any possible impacts.

    The most important observations of Apophis will occur in 2029, when asteroid scientists around the world will have an opportunity to conduct a close-up study of the Apophis’ size, shape, composition and possibly even its interior.

    At the conference, scientists will discuss questions like “How will Earth’s gravity affect the asteroid as it passes by?,” “Can we use Apophis’ flyby to learn about an asteroid’s interior?” and “Should we send a spacecraft mission to Apophis?”

    “We already know that the close encounter with Earth will change Apophis’ orbit, but our models also show the close approach could change the way this asteroid spins, and it is possible that there will be some surface changes, like small avalanches,” said Davide Farnocchia, an astronomer at JPL’s Center for Near Earth Objects Studies (CNEOS), who is co-chairing the April 30 session on Apophis with Brozović.

    “Apophis is a representative of about 2,000 currently known Potentially Hazardous Asteroids (PHAs),” said Paul Chodas, director of CNEOS. “By observing Apophis during its 2029 flyby, we will gain important scientific knowledge that could one day be used for planetary defense.”

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    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, 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.

    Caltech Logo

    NASA image

     
  • richardmitnick 10:10 am on April 28, 2019 Permalink | Reply
    Tags: , , , , , , , Jupiter's Europa moon, NASA JPL - Caltech, , OPAG-Outer Planet Assessment Group   

    From Nautilus: “Why Europa Is the Place to Go for Alien Life” 

    Nautilus

    From Nautilus

    April 18, 2019
    Corey S. Powell

    1
    This image shows a view of the trailing hemisphere of Jupiter’s ice-covered satellite, Europa, in approximate natural color. Long, dark lines are fractures in the crust, some of which are more than 3,000 kilometers (1,850 miles) long. The bright feature containing a central dark spot in the lower third of the image is a young impact crater some 50 kilometers (31 miles) in diameter. This crater has been provisionally named “Pwyll” for the Celtic god of the underworld. Europa is about 3,160 kilometers (1,950 miles) in diameter, or about the size of Earth’s moon. This image was taken on September 7, 1996, at a range of 677,000 kilometers (417,900 miles) by the solid state imaging television camera onboard the Galileo spacecraft during its second orbit around Jupiter. The image was processed by Deutsche Forschungsanstalt fuer Luftund Raumfahrt e.V., Berlin, Germany. NASA/JPL/DLR.

    NASA/Galileo 1989-2003

    I have seen the future of space exploration, and it looks like a cue ball covered with brown scribbles. I am talking about Europa, the 1,940-mile-wide, nearly white, and exceedingly smooth satellite of Jupiter. It is an enigmatic world that is, in many ways, almost a perfect inversion of Earth. It is also one of the most plausible places to look for alien life. If it strikes you that those two statements sound rather contradictory—why yes, they do. And therein lies the reason why Europa just might be the most important world in the solar system right now. The Europa Clipper spacecraft is scheduled to launch in 2023 to probe the mysterious moon, according to NASA’s 2020 budget proposal.

    NASA/Europa Clipper annotated

    The unearthly aspects of Europa are literally un-earthly : This is an orb sculpted from water ice, not from rock. It has ice tectonics in place of shifting continents, salty ocean in place of mantle, and vapor plumes in place of volcanoes. The surface scribbles may be dirty ocean material that leaked up through the icy equivalent of an earthquake fault.

    From a terrestrial perspective, Europa is built all wrong, with its solid crust up top and water down below. From the perspective of alien life, though, that might be a perfectly dandy arrangement. Beneath its frozen crust, Europa holds twice as much liquid water as exists in all of our planet’s oceans combined. Astrobiologists typically flag water as life’s number-one requirement; well, Europa is drowning in it. Just below the ice line, conditions might resemble the environment on the underside of Antarctic ice sheets. At the bottom of its buried ocean, Europa may have an active system of hydrothermal vents. Both of these are vibrant habitats on Earth.

    Adding a new twist to the story, Europa’s water may sometimes escape its icy confines. On at least four occasions, the Hubble Space Telescope has detected what appear to be large plumes of water vapor erupting from Europa. That detection has confirmed and expanded on the scientific ideas about what makes Europa such a dynamic world. Europa travels in a slightly oval orbit around Jupiter, causing it to get alternately squeezed and stretched by the giant planet’s gravity. The flexing creates intense friction inside the satellite and generates enough heat to maintain a warm ocean beneath Europa’s frozen outer shell. The presence of a plume suggests that the stretching of Europa also opens and closes a network of fissures that allow buried water to erupt as geysers.

    If the geysers consist of ocean water shooting all the way through the crust, they could carry traces of aquatic life with them. And if the plumes rise high enough, a future spacecraft could fly right through them, sniffing for biochemicals.

    2
    SIGNS FROM BELOW: Salty seawater appears to have breached Europa’s frozen exterior, creating a network of red-brown streaks. Perhaps traces of aquatic life were carried along in the process? This scene is 100 miles wide. NASA/JPL-Caltech/SETI Institute

    You can see why people were giddy at a 2015 OPAG meeting held at NASA’s Ames Research Center. A regular forum for geeking out about ice worlds, the OPAG gatherings—short for Outer Planet Assessment Group—feel halfway between the corporate swarm of a MacWorld expo and a vinyl record fair. They are where true believers mingle with the newbies, showing off the latest science, kicking around speculative ideas, and developing strategies for exploration. With each new bit of data, they have grown increasingly convinced that Europa, not Mars, is the place to go to search for alien life. Finding the plume on Europa was another shot of adrenaline. The room went fervently silent as Lorenz Roth of Sweden’s Royal Institute of Technology, calling in via a fuzzy phone line, reported on the latest search for a recurrence of such water eruptions (no luck yet, alas).

    Another significant piece of news was hanging over the OPAG meeting: The discovery that Europa has plate tectonics, like Earth and unlike any other world we know of. Tectonics describes a process in which the crust moves about and cycles back and forth into the interior. Louise Prockter of Johns Hopkins University’s Applied Physics Laboratory co-discovered this style of activity on Europa by painstakingly reconstructing old images from the Galileo spacecraft, which circled Jupiter from 1995 to 2003. (Analysis of other Galileo data suggests the probe flew right past a Europan water plume in 1997, but scientists didn’t realize it at the time.)

    As Prockter explained to me at the meeting, a mobile crust potentially does two important things. It cycles surface ice, along with all the compounds it develops during exposure to the sun, down into the dark ocean; that chemical flow could be crucial for supplying the ocean with nutrients. The motion of the crust also brings ocean material up to the surface, where prying human eyes can seek clues about the Europan ocean without actually drilling down into it.

    Bolstered by these discoveries, the cult of Europa has now escaped the confines of the OPAG meetings. A successful mission to Europa would bring into focus the incredible ice-and-ocean environment of Europa. It would also help scientists understand ice worlds in general. Icy moons, dwarf planets, and giant asteroids are the norm in the vast outer zone of the solar system, and if they repeat the pattern of Europa they may contain much of the solar system’s habitable real estate. There is good reason to think that ice worlds are similarly abundant around other stars as well. Putting all of these new ideas together suggests that the Milky Way may collectively contain tens of billions of life-friendly iceboxes.

    But if these stunning extrapolations seem to suggest that scientists are starting to get a handle on how Europa works, allow me to suggest otherwise. Europa is still largely a big, icy ball of confusion.

    3
    Under the Ice: An artist’s conception of Europa (foreground), Jupiter (right) and Jupiter’s innermost large moon, Io (middle), shows salts bubbling up from Europa’s liquid ocean to reach its frozen surface. NASA/JPL-Caltech.

    Almost everything we know about the surface of Europa comes from NASA’s Galileo mission, which reached Jupiter in 1995. During its eight-year mission, Galileo mapped most of Europa, but at a crude resolution of about one mile per pixel. For comparison, today’s best Mars images show features as small as three feet. Elizabeth “Zibi” Turtle of the Hopkins Applied Physics Lab promises that the camera on NASA’s upcoming Europa probe will achieve a similar level of clarity. Until then, imagine trying to navigate using a map that doesn’t show anything smaller than one mile and you will get a sense of how far the Europa scientists have to go.

    What’s more, at a very basic level, planetary scientists still do not have a good handle on how geology (or maybe we should say “glaciology?”) works in frozen settings. Ice, you see, is not just ice. Robert Pappalardo of NASA’s Jet Propulsion Laboratory, the ponytail-wielding mission scientist for the agency’s upcoming Europa probe, spelled out some of the complexities to me. On Europa, surface temperatures on a warm day at the equator might rise up to -210 degrees Fahrenheit; at the poles, the lows plunge to -370 degrees Fahrenheit. Under those conditions, water is properly thought of as a mineral, and ice has approximately the consistency of concrete. In many ways it is remarkably similar to rock in how it fractures, faults, and shatters. But even in such a deep freeze, surface ice can sublimate—evaporate directly from solid to gas—in a way that rock does not. Icy material tends to boil off from darker, warmer regions and collect on lighter, cooler ones, producing an exotic kind of weathering that rearranges the landscape without any wind or rain.

    All sorts of other things are happening on the surface of Europa. Jupiter has a huge, potent magnetic field that bombards its satellite with radiation: about 500 rem per day on average, which you can more easily judge as a dose strong enough to make you sick in one hour and to kill you in 24. That radiation quickly breaks down any organic compounds, greatly complicating the search for life, but produces all kinds of other complex chemistry. A lab experiment at the Jet Propulsion Laboratory suggests that the colors of Europa’s streaks are produced by irradiated ocean salts. These and other fragmented molecules, along with a steady rain of organic material delivered by comet impacts, could be used as energy sources for life when they circulate back down into the ocean, where any living things would be well protected.

    The movement of Europa’s crust—its icy outer shell—is another broad area of mystery. On ice worlds, Pappalardo notes, water takes on the role of magma and hot rock deep below the surface, but once again ice and rock are not quite the same. Warm ice turns soft, almost slushy, under high pressure and slowly flows. There could be complicated circulation patterns contained entirely within the crust, which is perhaps 10 to 15 miles thick (or maybe more or less; that is yet another mystery that the Europa mission will investigate). Pools of liquid water might exist trapped within the shell, cut off from the underlying ocean. Plumes of water at the surface might not originate directly from the ocean; it is possible that they come from these intermediate lakes, analogous to the largely unexplored Lake Vostok in Antarctica.

    At the OPAG meeting, seemingly narrow arguments about the circulation of ice sparked colorful debates about prospects for life on Europa and, by extension, on the myriad other ice worlds out there. Britney Schmidt of Georgia Tech wondered if the active geology (glaciology) on Europa occurs entirely within the crust. If material does not circulate at all between surface and ocean, Europa is sealed tight. Life could not get any fresh chemicals from up above, and if it somehow manages to survive anyway we might never know unless we find a way to dig a hole all the way through. Several researchers at OPAG suggested that meaningful answers will require a surface lander; one energetic audience member repeatedly argued for sending an impactor—a high-speed bowling ball, essentially—to smack the surface and shake loose any possible buried microbes.

    As for the Europan ocean itself, that runs even deeper into what you might call aqua incognita . If the surface truly is streaked with salts, as the recent experiments indicate, that suggests a mineral-rich ocean in which waters interact vigorously with a rocky seafloor at the bottom. A likely source of such interaction is a network of hydrothermal vents powered by Europa’s internal heat; such vents could provide chemical energy to sustain Europan life, as they do on Earth. But how much total hydrothermal activity goes on? Are the acidity and salinity conducive to life? How much organic material is down there? The scientists egged each other on with provocative questions that, as yet, have no answers.

    When (or if) we will find out will depend, in large part, on how much of Europa’s inner nature is evident from the outside. The conversations at OPAG sometimes devolved into something resembling a college existential argument: If an alien swims in Europa’s ocean and nobody is able to see it, is it really alive?

    The Europa faithful have been waiting a long time for a mission that would wipe away those kinds of arguments, or at least ground them in hard data. That wait has been full of whipsaw swings between optimism and disappointment. NASA’s planned Europa Orbiter got a green light in 1999, only to be cancelled in 2002. The agency rebounded with a proposal for an even more ambitious, nuclear-propelled Jupiter Icy Moons Orbiter, which looked incredible until it got delayed and finally cancelled in 2006. A proposed joint venture with the European Space Agency never even got that far, though the Europeans are going ahead with their part of the project, which will send a probe to Ganymede, another one of Jupiter’s icy moons, in 2030.

    The Europa Clipper, outfitted with scientific instruments that include cameras and spectrometers, will swoop repeatedly past the moon and produce images that determine its composition. There is a chance the Europa mission will include a lander. Funding does not exist yet, but Adam Steltzner—the hearty engineer who figured out how to land the two-ton Curiosity rover safely on Mars—assures me that from a technical standpoint it would not be difficult to design a small probe equipped with rockets to allow a soft touchdown on Europa. There it could drill into the surface and search for possible organic material that has not been degraded by the radiation blasts from Jupiter.

    What you won’t see, the OPAG boffins all sadly agreed, is one of those cool Europa submarines that show up on the speculative “future mission concept” NASA web pages. Getting a probe into Lake Vostok right here on Earth has proven a daunting challenge. Drilling through 10 miles or more of Europan ice and exploring an alien ocean by remote control is something we still don’t know how to do, and certainly not with any plausible future NASA budget.

    No matter. Even the no-frills version of NASA’s current Europa plan will unleash a flood of information about how ice worlds work, and about how likely they are to support life. If the answers are as exciting as many scientists hope—and as I strongly expect—it will bolster the case for future missions to Titan, Enceladus, and some of Europa’s other beckoning cousins. It will reshape the search for habitable worlds around other stars as well. Right now astronomers are mostly focused on finding other Earthlike planets, but maybe that is not where most of the action is. Perhaps most of the life in the universe is locked away, safe but almost undetectable, beneath shells of ice.

    Whether or not Europa is home to alien organisms, it will tell us about the range of what life can be, and where it can be. That one icy moon will help cure science of its rocky-planet chauvinism. Hey, who you calling cue ball?

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    Welcome to Nautilus. We are delighted you joined us. We are here to tell you about science and its endless connections to our lives. Each month we choose a single topic. And each Thursday we publish a new chapter on that topic online. Each issue combines the sciences, culture and philosophy into a single story told by the world’s leading thinkers and writers. We follow the story wherever it leads us. Read our essays, investigative reports, and blogs. Fiction, too. Take in our games, videos, and graphic stories. Stop in for a minute, or an hour. Nautilus lets science spill over its usual borders. We are science, connected.

     
  • richardmitnick 9:07 am on April 24, 2019 Permalink | Reply
    Tags: , , , , , , NASA JPL - Caltech   

    From JPL-Caltech: “NASA’s InSight Lander Captures Audio of First Likely ‘Quake’ on Mars” 

    NASA JPL Banner

    From JPL-Caltech

    April 23, 2019

    Andrew Good
    Jet Propulsion Laboratory, Pasadena, Calif.
    818-393-2433
    andrew.c.good@jpl.nasa.gov

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

    Alana Johnson
    Headquarters, Washington
    202-358-1501
    alana.r.johnson@nasa.gov

    NASA’s Mars InSight lander has measured and recorded for the first time ever a likely “marsquake.”

    NASA/Mars InSight Lander

    The faint seismic signal, detected by the lander’s Seismic Experiment for Interior Structure (SEIS) instrument, was recorded on April 6, the lander’s 128th Martian day, or sol. This is the first recorded trembling that appears to have come from inside the planet, as opposed to being caused by forces above the surface, such as wind. Scientists still are examining the data to determine the exact cause of the signal.

    2
    This image, taken March 19, 2019 by a camera on NASA’s Mars InSight lander, shows the rover’s domed Wind and Thermal Shield, which covers its seismometer, the Seismic Experiment for Interior Structure, and the Martian surface in the background. Credits: NASA/JPL-Caltech


    This video and audio illustrates a seismic event detected by NASA’s Mars InSight rover on April 6, 2019, the 128th Martian day, or sol, of the mission. Three distinct kinds of sounds can be heard, all of them detected as ground vibrations by the spacecraft’s seismometer, called the Seismic Experiment for Interior Structure (SEIS): noise from Martian wind, the seismic event itself, and the spacecraft’s robotic arm as it moves to take pictures. Credits: NASA/JPL-Caltech/CNES/IPGP/Imperial College London

    “InSight’s first readings carry on the science that began with NASA’s Apollo missions,” said InSight Principal Investigator Bruce Banerdt of NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California. “We’ve been collecting background noise up until now, but this first event officially kicks off a new field: Martian seismology!”

    The new seismic event was too small to provide solid data on the Martian interior, which is one of InSight’s main objectives. The Martian surface is extremely quiet, allowing SEIS, InSight’s specially designed seismometer, to pick up faint rumbles. In contrast, Earth’s surface is quivering constantly from seismic noise created by oceans and weather. An event of this size in Southern California would be lost among dozens of tiny crackles that occur every day.

    “The Martian Sol 128 event is exciting because its size and longer duration fit the profile of moonquakes detected on the lunar surface during the Apollo missions,” said Lori Glaze, Planetary Science Division director at NASA Headquarters.

    NASA’s Apollo astronauts installed five seismometers that measured thousands of quakes while operating on the Moon between 1969 and 1977, revealing seismic activity on the Moon. Different materials can change the speed of seismic waves or reflect them, allowing scientists to use these waves to learn about the interior of the Moon and model its formation. NASA currently is planning to return astronauts to the Moon by 2024, laying the foundation that will eventually enable human exploration of Mars.

    InSight’s seismometer, which the lander placed on the planet’s surface on Dec. 19, 2018, will enable scientists to gather similar data about Mars. By studying the deep interior of Mars, they hope to learn how other rocky worlds, including Earth and the Moon, formed.

    3
    This set of images from the Instrument Deployment Camera shows NASA’s InSight lander placing its first instrument onto the surface of Mars, completing a major mission milestone. Image Credit: NASA/JPL-Caltech.

    Three other seismic signals occurred on March 14 (Sol 105), April 10 (Sol 132) and April 11 (Sol 133). Detected by SEIS’ more sensitive Very Broad Band sensors, these signals were even smaller than the Sol 128 event and more ambiguous in origin. The team will continue to study these events to try to determine their cause.

    Regardless of its cause, the Sol 128 signal is an exciting milestone for the team.

    “We’ve been waiting months for a signal like this,” said Philippe Lognonné, SEIS team lead at the Institut de Physique du Globe de Paris (IPGP) in France. “It’s so exciting to finally have proof that Mars is still seismically active. We’re looking forward to sharing detailed results once we’ve had a chance to analyze them.”

    Most people are familiar with quakes on Earth, which occur on faults created by the motion of tectonic plates. Mars and the Moon do not have tectonic plates, but they still experience quakes – in their cases, caused by a continual process of cooling and contraction that creates stress. This stress builds over time, until it is strong enough to break the crust, causing a quake.

    Detecting these tiny quakes required a huge feat of engineering. On Earth, high-quality seismometers often are sealed in underground vaults to isolate them from changes in temperature and weather. InSight’s instrument has several ingenious insulating barriers, including a cover built by JPL called the Wind and Thermal Shield, to protect it from the planet’s extreme temperature changes and high winds.

    SEIS has surpassed the team’s expectations in terms of its sensitivity. The instrument was provided for InSight by the French space agency, Centre National d’Études Spatiales (CNES), while these first seismic events were identified by InSight’s Marsquake Service team, led by the Swiss Federal Institute of Technology.

    “We are delighted about this first achievement and are eager to make many similar measurements with SEIS in the years to come,” said Charles Yana, SEIS mission operations manager at CNES.

    JPL manages InSight for NASA’s Science Mission Directorate. InSight is part of NASA’s Discovery Program, managed by the agency’s Marshall Space Flight Center in Huntsville, Alabama. Lockheed Martin Space in Denver built the InSight spacecraft, including its cruise stage and lander, and supports spacecraft operations for the mission.

    A number of European partners, including CNES and the German Aerospace Center (DLR), support the InSight mission. CNES provided the SEIS instrument to NASA, with the principal investigator at IPGP. Significant contributions for SEIS came from IPGP; the Max Planck Institute for Solar System Research in Germany; the Swiss Federal Institute of Technology (ETH Zurich) in Switzerland; Imperial College London and Oxford University in the United Kingdom; and JPL. DLR provided the Heat Flow and Physical Properties Package (HP3) instrument, with significant contributions from the Space Research Center of the Polish Academy of Sciences and Astronika in Poland. Spain’s Centro de Astrobiología supplied the temperature and wind sensors.

    For more information about InSight, visit:

    https://www.nasa.gov/insight

    For more information about the agency’s Moon to Mars activities, visit

    https://www.nasa.gov/topics/moon-to-mars

    See the full article here .


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    Please help promote STEM in your local schools.

    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, 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 2:04 pm on April 15, 2019 Permalink | Reply
    Tags: "NASA's Cassini Reveals Surprises with Titan's Lakes", , , , , NASA JPL - Caltech,   

    From JPL-Caltech: “NASA’s Cassini Reveals Surprises with Titan’s Lakes” 

    NASA JPL Banner

    From JPL-Caltech

    April 15, 2019

    Gretchen McCartney
    Jet Propulsion Laboratory, Pasadena, Calif.
    818-393-6215
    gretchen.p.mccartney@jpl.nasa.gov

    JoAnna Wendel
    NASA Headquarters, Washington
    202-358-1003
    joanna.r.wendel@nasa.gov

    1
    This near-infrared, color view from Cassini shows the sun glinting off of Titan’s north polar seas. Image credit: NASA/JPL-Caltech/Univ. Arizona/Univ. Idaho
    October 30, 2014- 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 (see PIA17470) and the sun glinting off of them (see PIA12481 and PIA18433) in the past, this is the first time both have been seen together in the same view.

    NASA/ESA/ASI Cassini-Huygens Spacecraft

    On its final flyby of Saturn’s largest moon in 2017, NASA’s Cassini spacecraft gathered radar data revealing that the small liquid lakes in Titan’s northern hemisphere are surprisingly deep, perched atop hills and filled with methane.

    3
    PIA20021: Mystery Feature Evolves in Titan’s Ligeia Mare

    4
    The existence of oceans or lakes of liquid methane on Saturn’s moon Titan was predicted more than 20 years ago. But with a dense haze preventing a closer look it has not been possible to confirm their presence. Until the Cassini flyby of July 22, 2006, that is.

    The new findings, published April 15 in Nature Astronomy, are the first confirmation of just how deep some of Titan’s lakes are (more than 300 feet, or 100 meters) and of their composition. They provide new information about the way liquid methane rains on, evaporates from and seeps into Titan – the only planetary body in our solar system other than Earth known to have stable liquid on its surface.

    Scientists have known that Titan’s hydrologic cycle works similarly to Earth’s – with one major difference. Instead of water evaporating from seas, forming clouds and rain, Titan does it all with methane and ethane. We tend to think of these hydrocarbons as a gas on Earth, unless they’re pressurized in a tank. But Titan is so cold that they behave as liquids, like gasoline at room temperature on our planet.

    Scientists have known that the much larger northern seas are filled with methane, but finding the smaller northern lakes filled mostly with methane was a surprise. Previously, Cassini data measured Ontario Lacus, the only major lake in Titan’s southern hemisphere. There they found a roughly equal mix of methane and ethane. Ethane is slightly heavier than methane, with more carbon and hydrogen atoms in its makeup.

    “Every time we make discoveries on Titan, Titan becomes more and more mysterious,” said lead author Marco Mastrogiuseppe, Cassini radar scientist at Caltech in Pasadena, California. “But these new measurements help give an answer to a few key questions. We can actually now better understand the hydrology of Titan.”

    Adding to the oddities of Titan, with its Earth-like features carved by exotic materials, is the fact that the hydrology on one side of the northern hemisphere is completely different than the that of other side, said Cassini scientist and co-author Jonathan Lunine of Cornell University in Ithaca, New York.

    “It is as if you looked down on the Earth’s North Pole and could see that North America had completely different geologic setting for bodies of liquid than Asia does,” Lunine said.

    On the eastern side of Titan, there are big seas with low elevation, canyons and islands. On the western side: small lakes. And the new measurements show the lakes perched atop big hills and plateaus. The new radar measurements confirm earlier findings that the lakes are far above sea level, but they conjure a new image of landforms – like mesas or buttes – sticking hundreds of feet above the surrounding landscape, with deep liquid lakes on top.

    The fact that these western lakes are small – just tens of miles across – but very deep also tells scientists something new about their geology: It’s the best evidence yet that they likely formed when the surrounding bedrock of ice and solid organics chemically dissolved and collapsed. On Earth, similar water lakes are known as karstic lakes. Occurring in in areas like Germany, Croatia and the United States, they form when water dissolves limestone bedrock.

    Alongside the investigation of deep lakes, a second paper in Nature Astronomy helps unravel more of the mystery of Titan’s hydrologic cycle. Researchers used Cassini data to reveal what they call transient lakes. Different sets of observations – from radar and infrared data – seem to show liquid levels significantly changed.

    The best explanation is that there was some seasonally driven change in the surface liquids, said lead author Shannon MacKenzie, planetary scientist at the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland. “One possibility is that these transient features could have been shallower bodies of liquid that over the course of the season evaporated and infiltrated into the subsurface,” she said.

    These results and the findings from the Nature Astronomy paper on Titan’s deep lakes support the idea that hydrocarbon rain feeds the lakes, which then can evaporate back into the atmosphere or drain into the subsurface, leaving reservoirs of liquid stored below.

    Cassini, which arrived in the Saturn system in 2004 and ended its mission in 2017 by deliberately plunging into Saturn’s atmosphere, mapped more than 620,000 square miles (1.6 million square kilometers) of liquid lakes and seas on Titan’s surface. It did the work with the radar instrument, which sent out radio waves and collected a return signal (or echo) that provided information about the terrain and the liquid bodies’ depth and composition, along with two imaging systems that could penetrate the moon’s thick atmospheric haze.

    The crucial data for the new research were gathered on Cassini’s final close flyby of Titan, on April 22, 2017. It was the mission’s last look at the moon’s smaller lakes, and the team made the most of it. Collecting echoes from the surfaces of small lakes while Cassini zipped by Titan was a unique challenge.

    “This was Cassini’s last hurrah at Titan, and it really was a feat,” Lunine said

    The Cassini-Huygens mission is a cooperative project of NASA, ESA (European Space Agency) and the Italian Space Agency. NASA’s Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the mission for NASA’s Science Mission Directorate, Washington. JPL designed, developed and assembled the Cassini orbiter. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the U.S. and several European countries.

    More information about Cassini can be found here:

    https://solarsystem.nasa.gov/cassini

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    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, 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 1:00 pm on April 1, 2019 Permalink | Reply
    Tags: "Europa Clipper High-Gain Antenna Undergoes Testing", , , , , , NASA JPL - Caltech   

    From JPL-Caltech: “Europa Clipper High-Gain Antenna Undergoes Testing” 

    NASA JPL Banner

    From JPL-Caltech

    April 1, 2019

    Gretchen McCartney
    Jet Propulsion Laboratory, Pasadena, Calif.
    818-393-6215
    gretchen.p.mccartney@jpl.nasa.gov

    JoAnna Wendel
    NASA Headquarters, Washington
    202-358-1003
    joanna.r.wendel@nasa.gov

    Written by Joe Atkinson
    NASA Langley Research Center, Hampton, Va.
    757-864-5644
    joseph.s.atkinson@nasa.gov

    1
    A full-scale prototype of the high-gain antenna on NASA’s Europa Clipper spacecraft is undergoing testing in the Experimental Test Range at NASA’s Langley Research Center in Hampton, Virginia. Credit: NASA/Langley

    It probably goes without saying, but this isn’t your everyday satellite dish.

    In fact, it’s not a satellite dish at all. It’s a high-gain antenna (HGA), and a future version of it will send and receive signals to and from Earth from a looping orbit around Jupiter.

    The antenna will take that long journey aboard NASA’s Europa Clipper, a spacecraft that will conduct detailed reconnaissance of Jupiter’s moon Europa to see whether the icy orb could harbor conditions suitable for life.

    NASA/Europa Clipper annotated

    Scientists believe there’s a massive salty ocean beneath Europa’s icy surface. The antenna will beam back high-resolution images and scientific data from Europa Clipper’s cameras and science instruments.

    The full-scale prototype antenna, which at 10 feet (3 meters) tall is the same height as a standard basketball hoop, is in the Experimental Test Range (ETR) at NASA’s Langley Research Center in Hampton, Virginia. Researchers from NASA’s Jet Propulsion Laboratory in Pasadena, California, the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, and Langley are testing the prototype in the ETR in order to assess its performance and demonstrate the high pointing accuracies required for the Europa Clipper mission.

    The ETR is an indoor electromagnetic test facility that allows researchers to characterize transmitters, receivers, antennas and other electromagnetic components and subsystems in a scientifically controlled environment.

    “Several years ago we scoured the country to find a facility that was capable of making the difficult measurements that would be required on the HGA and found that the ETR clearly was it,”said Thomas Magner, assistant project manager for Europa Clipper at the Applied Physics Laboratory. “The measurements that will be performed in the ETR will demonstrate that the Europa Clipper mission can get a large volume of scientific data back to Earth and ultimately determine the habitability of Europa.”

    Tests on this prototype antenna are scheduled to wrap up soon; however, researchers plan to return to the ETR in 2020 to conduct additional tests on Europa Clipper’s high-gain antenna flight article. Europa Clipper plans to launch in the 2020s, with travel time to Jupiter taking three to seven years (depending on the launch vehicle and which planetary alignments can be utilized).

    JPL manages the Europa Clipper mission for NASA’s Science Mission Directorate. The multiple-flyby concept was developed in partnership with the Applied Physics Laboratory.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    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, 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 12:13 pm on March 27, 2019 Permalink | Reply
    Tags: "'Space Butterfly' Is Home to Hundreds of Baby Stars", NASA JPL - Caltech, , Officially named W40 the butterfly is a nebula - a giant cloud of gas and dust in space where new stars may form., Serpens South   

    From JPL-Caltech: “‘Space Butterfly’ Is Home to Hundreds of Baby Stars” 

    NASA JPL Banner

    From JPL-Caltech

    March 27, 2019

    Calla Cofield
    Jet Propulsion Laboratory, Pasadena, Calif.
    626-808-2469
    calla.e.cofield@jpl.nasa.gov

    1

    What looks like a red butterfly in space is in reality a nursery for hundreds of baby stars, revealed in this infrared image from NASA’s Spitzer Space Telescope.

    NASA/Spitzer Infrared Telescope

    Officially named W40, the butterfly is a nebula – a giant cloud of gas and dust in space where new stars may form. The butterfly’s two “wings” are giant bubbles of hot, interstellar gas blowing from the hottest, most massive stars in this region.

    Besides being beautiful, W40 exemplifies how the formation of stars results in the destruction of the very clouds that helped create them. Inside giant clouds of gas and dust in space, the force of gravity pulls material together into dense clumps. Sometimes these clumps reach a critical density that allows stars to form at their cores. Radiation and winds coming from the most massive stars in those clouds – combined with the material spewed into space when those stars eventually explode – sometimes form bubbles like those in W40. But these processes also disperse the gas and dust, breaking up dense clumps and reducing or halting new star formation.

    The material that forms W40’s wings was ejected from a dense cluster of stars that lies between the wings in the image. The hottest, most massive of these stars, W40 IRS 1a, lies near the center of the star cluster.

    W40 is about 1,400 light-years from the Sun, about the same distance as the well-known Orion nebula, although the two are almost 180 degrees apart in the sky. They are two of the nearest regions in which massive stars – with masses upwards of 10 times that of the Sun – have been observed to be forming.

    Another cluster of stars, named Serpens South, can be seen to the upper right of W40 in this image. Although both Serpens South and the cluster at the heart of W40 are young in astronomical terms (less than a few million years old), Serpens South is the younger of the two. Its stars are still embedded within their cloud but will someday break out to produce bubbles like those of W40. Spitzer has also produced a more detailed image of the Serpens South cluster.

    4

    Stellar members of Serpens South star cluster can be seen as the green, yellow, and orange tinted specks sitting atop the black dust lane running down the center of the image. Like raindrops, stars form when thick patches of cosmic clouds condense.

    Tints of green in the image represent hot hydrogen gas excited when high-speed jets of gas ejected by infant stars collide with the cool gas in the surrounding cloud.

    Wisps of red in the background are organic molecules called polycyclic aromatic hydrocarbons (PAHs), which are being excited by stellar radiation from a neighboring star-forming region located to the east of this image, called W40. On Earth PAHs are found on charred barbeque grills and in the sooty automobile exhaust.

    This Spitzer picture is composed of three images taken with the telescope’s Infrared Array Camera (IRAC) at 3.6 (blue), 4.5 (green), and 5.8 (red) microns.

    A mosaic of Spitzer’s observation of the W40 star-forming region was originally published as part of the Massive Young stellar clusters Study in Infrared and X-rays (MYStIX) survey of young stellar objects.

    The Spitzer picture ‘Space Butterfly’ is composed of four images taken with the telescope’s Infrared Array Camera (IRAC) in different wavelengths of infrared light: 3.6, 4.5, 5.8 and 8.0 µm (shown as blue, green, orange and red). Organic molecules made of carbon and hydrogen, called polycyclic aromatic hydrocarbons (PAHs), are excited by interstellar radiation and become luminescent at wavelengths near 8.0 microns, giving the nebula its reddish features. Stars are brighter at the shorter wavelengths, giving them a blue tint. Some of the youngest stars are surrounded by dusty disks of material, which glow with a yellow or red hue.

    See the full article here .


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    Please help promote STEM in your local schools.

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  • richardmitnick 2:02 pm on March 5, 2019 Permalink | Reply
    Tags: "Galactic Wind Provides Clues to Evolution of Galaxies", "The space between galaxies is not empty" said Enrique Lopez-Rodriguez a Universities Space Research Association (USRA) scientist working on the SOFIA team. "It contains gas and dust - which are the s, Besides being a classic example of a starburst galaxy because it is forming an extraordinary number of new stars compared with most other galaxies Messier 82 also has strong winds blowing gas and dust, , NASA JPL - Caltech, , Researchers found for the first time that the galactic wind flowing from the center of the Cigar Galaxy (M82) is aligned along a magnetic field and transports a very large mass of gas and dust - the e, Researchers using the airborne observatory SOFIA found definitively that the wind from the Cigar Galaxy not only transports a huge amount of gas and dust into the intergalactic medium but also drags t, SOFIA's newest instrument- the High-resolution Airborne Wideband Camera-Plus or HAWC+- uses far-infrared light to observe celestial dust grains which align along magnetic field lines. From these resul, The Cigar Galaxy (also known as M82) is famous for its extraordinary speed in making new stars with stars being born 10 times faster than in the Milky Way. Now data from the Stratospheric Observatory , These observations indicate that the powerful winds associated with the starburst phenomenon could be one of the mechanisms responsible for seeding material and injecting a magnetic field into the nea   

    From JPL-Caltech: “Galactic Wind Provides Clues to Evolution of Galaxies” 

    NASA JPL Banner

    From JPL-Caltech

    March 5, 2019
    Calla Cofield
    Jet Propulsion Laboratory, Pasadena, Calif.
    626-808-2469
    calla.e.cofield@jpl.nasa.gov

    Written by Kassandra Bell and Arielle Moullet, USRA SOFIA Science Center

    1
    A composite image of the Cigar Galaxy (also called Messier 82), a starburst galaxy about 12 million light-years away in the constellation Ursa Major. The magnetic field detected by the High-resolution Airborne Wideband Camera-Plus instrument (known as HAWC+) on SOFIA (the Stratospheric Observatory for Infrared Astronomy), shown as streamlines, appears to follow the bipolar outflows (red) generated by the intense nuclear starburst. The image combines visible starlight (gray) and a tracing of hydrogen gas (red) observed from the Kitt Peak Observatory, with near-infrared and mid-infrared starlight and dust (yellow) observed by SOFIA and the Spitzer Space Telescope.

    NASA SOFIA High-resolution Airborne Wideband Camera-Plus HAWC+ Camera

    NASA/DLR SOFIA

    Kitt Peak National Observatory of the Quinlan Mountains in the Arizona-Sonoran Desert on the Tohono O’odham Nation, 88 kilometers 55 mi west-southwest of Tucson, Arizona, Altitude 2,096 m (6,877 ft)

    NASA/Spitzer Infrared Telescope

    The Cigar Galaxy (also known as M82) is famous for its extraordinary speed in making new stars, with stars being born 10 times faster than in the Milky Way. Now, data from the Stratospheric Observatory for Infrared Astronomy, or SOFIA, have been used to study this galaxy in greater detail, revealing how material that affects the evolution of galaxies may get into intergalactic space.

    Researchers found, for the first time, that the galactic wind flowing from the center of the Cigar Galaxy (M82) is aligned along a magnetic field and transports a very large mass of gas and dust – the equivalent mass of 50 million to 60 million Suns.

    “The space between galaxies is not empty,” said Enrique Lopez-Rodriguez, a Universities Space Research Association (USRA) scientist working on the SOFIA team. “It contains gas and dust – which are the seed materials for stars and galaxies. Now, we have a better understanding of how this matter escaped from inside galaxies over time.”

    Besides being a classic example of a starburst galaxy, because it is forming an extraordinary number of new stars compared with most other galaxies, Messier 82 also has strong winds blowing gas and dust into intergalactic space. Astronomers have long theorized that these winds would also drag the galaxy’s magnetic field in the same direction, but despite numerous studies, there has been no observational proof of the concept.

    Researchers using the airborne observatory SOFIA found definitively that the wind from the Cigar Galaxy not only transports a huge amount of gas and dust into the intergalactic medium, but also drags the magnetic field so it is perpendicular to the galactic disc. In fact, the wind drags the magnetic field more than 2,000 light-years across – close to the width of the wind itself.

    “One of the main objectives of this research was to evaluate how efficiently the galactic wind can drag along the magnetic field,” said Lopez-Rodriguez. “We did not expect to find the magnetic field to be aligned with the wind over such a large area.”

    These observations indicate that the powerful winds associated with the starburst phenomenon could be one of the mechanisms responsible for seeding material and injecting a magnetic field into the nearby intergalactic medium. If similar processes took place in the early universe, they would have affected the fundamental evolution of the first galaxies.

    The results were published in December 2018 in The Astrophysical Journal Letters.

    SOFIA’s newest instrument, the High-resolution Airborne Wideband Camera-Plus, or HAWC+, uses far-infrared light to observe celestial dust grains, which align along magnetic field lines. From these results, astronomers can infer the shape and direction of the otherwise invisible magnetic field. Far-infrared light provides key information about magnetic fields because the signal is clean and not contaminated by emission from other physical mechanisms, such as scattered visible light.

    “Studying intergalactic magnetic fields – and learning how they evolve – is key to understanding how galaxies evolved over the history of the universe,” said Terry Jones, professor emeritus at the University of Minnesota, in Minneapolis, and lead researcher for this study. “With SOFIA’s HAWC+ instrument, we now have a new perspective on these magnetic fields.”

    The HAWC+ instrument was developed and delivered to NASA by a multi-institution team led by the Jet Propulsion Laboratory. JPL scientist and HAWC+ Principal Investigator Darren Dowell, along with JPL scientist Paul Goldsmith, were part of the research team using HAWC+ to study the Cigar Galaxy.

    SOFIA, the Stratospheric Observatory for Infrared Astronomy, is a Boeing 747SP jetliner modified to carry a 106-inch diameter telescope. It is a joint project of NASA and the German Aerospace Center, DLR. NASA’s Ames Research Center in California’s Silicon Valley manages the SOFIA program, science and mission operations in cooperation with the Universities Space Research Association headquartered in Columbia, Maryland, and the German SOFIA Institute (DSI) at the University of Stuttgart. The aircraft is maintained and operated from NASA’s Armstrong Flight Research Center Hangar 703, in Palmdale, California.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    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, 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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