News Article | April 17, 2017
Mars has electrically charged metal atoms (ions) high in its atmosphere, according to new results from NASA's MAVEN spacecraft. The metal ions can reveal previously invisible activity in the mysterious electrically charged upper atmosphere (ionosphere) of Mars. "MAVEN has made the first direct detection of the permanent presence of metal ions in the ionosphere of a planet other than Earth," said Joseph Grebowsky of NASA's Goddard Space Flight Center in Greenbelt, Maryland. "Because metallic ions have long lifetimes and are transported far from their region of origin by neutral winds and electric fields, they can be used to infer motion in the ionosphere, similar to the way we use a lofted leaf to reveal which way the wind is blowing." Grebowsky is lead author of a paper on this research appearing April 10 in Geophysical Research Letters. MAVEN (Mars Atmosphere and Volatile Evolution Mission) is exploring the Martian upper atmosphere to understand how the planet lost most of its air, transforming from a world that could have supported life billions of years ago into a cold desert planet today. Understanding ionospheric activity is shedding light on how the Martian atmosphere is being lost to space, according to the team. The metal comes from a constant rain of tiny meteoroids onto the Red Planet. When a high-speed meteoroid hits the Martian atmosphere, it vaporizes. Metal atoms in the vapor trail get some of their electrons torn away by other charged atoms and molecules in the ionosphere, transforming the metal atoms into electrically charged ions. MAVEN has detected iron, magnesium, and sodium ions in the upper atmosphere of Mars over the last two years using its Neutral Gas and Ion Mass Spectrometer instrument, giving the team confidence that the metal ions are a permanent feature. "We detected metal ions associated with the close passage of Comet Siding Spring in 2014, but that was a unique event and it didn't tell us about the long-term presence of the ions," said Grebowsky. The interplanetary dust that causes the meteor showers is common throughout our solar system, so it's likely that all solar system planets and moons with substantial atmospheres have metal ions, according to the team. Sounding rockets, radar and satellite measurements have detected metal ion layers high in the atmosphere above Earth. There's also been indirect evidence for metal ions above other planets in our solar system. When spacecraft are exploring these worlds from orbit, sometimes their radio signals pass through the planet's atmosphere on the way to Earth, and sometimes portions of the signal have been blocked. This has been interpreted as interference from electrons in the ionosphere, some of which are thought to be associated with metal ions. However, long-term direct detection of the metal ions by MAVEN is the first conclusive evidence that these ions exist on another planet and that they are a permanent feature there. The team found that the metal ions behaved differently on Mars than on Earth. Earth is surrounded by a global magnetic field generated in its interior, and this magnetic field together with ionospheric winds forces the metal ions into layers. However, Mars has only local magnetic fields fossilized in certain regions of its crust, and the team only saw the layers near these areas. "Elsewhere, the metal ion distributions are totally unlike those observed at Earth," said Grebowsky. The research has other applications as well. For example it is unclear if the metal ions can affect the formation or behavior of high-altitude clouds. Also, detailed understanding of the meteoritic ions in the totally different Earth and Mars environments will be useful for better predicting consequences of interplanetary dust impacts in other yet-unexplored solar system atmospheres. "Observing metal ions on another planet gives us something to compare and contrast with Earth to understand the ionosphere and atmospheric chemistry better," said Grebowsky. The research was funded by the MAVEN mission. MAVEN's principal investigator is based at the University of Colorado's Laboratory for Atmospheric and Space Physics, Boulder. The university provided two science instruments and leads science operations, as well as education and public outreach, for the mission. NASA Goddard manages the MAVEN project and provided two science instruments for the mission. The University of California at Berkeley's Space Sciences Laboratory also provided four science instruments for the mission. Lockheed Martin built the spacecraft and is responsible for mission operations. NASA's Jet Propulsion Laboratory in Pasadena, California, provides navigation and Deep Space Network support, as well as the Electra telecommunications relay hardware and operations.
News Article | March 30, 2017
The San Diego Supercomputer Center (SDSC) at the University of California San Diego and the Simons Foundation’s Flatiron Institute in New York have reached an agreement under which the majority of SDSC’s data-intensive Gordon supercomputer will be used by Simons for ongoing research following completion of the system’s tenure as a National Science Foundation (NSF) resource on March 31. Under the agreement, SDSC will provide high-performance computing (HPC) resources and services on Gordon for the Flatiron Institute to conduct computationally-based research in astrophysics, biology, condensed matter physics, materials science, and other domains. The two-year agreement, with an option to renew for a third year, takes effect April 1, 2017. Under the agreement, the Flatiron Institute will have annual access to at least 90 percent of Gordon’s system capacity. SDSC will retain the rest for use by other organizations including UC San Diego's Center for Astrophysics & Space Sciences (CASS), as well as SDSC’s OpenTopography project and various projects within the Center for Applied Internet Data Analysis (CAIDA), which is based at SDSC. “We are delighted that the Simons Foundation has given Gordon a new lease on life after five years of service as a highly sought after XSEDE resource,” said SDSC Director Michael Norman, who also served as the principal investigator for Gordon. “We welcome the Foundation as a new partner and consider this to be a solid testimony regarding Gordon’s data-intensive capabilities and its myriad contributions to advancing scientific discovery.” “We are excited to have a big boost to the processing capacity for our researchers and to work with the strong team from San Diego,” said Ian Fisk, co-director of the Scientific Computing Core (SCC), which is part of the Flatiron Institute. David Spergel, director of the Flatiron Institute’s Center for Computational Astrophysics (CCA) said, “CCA researchers will use Gordon both for simulating the evolution and growth of galaxies, as well as for the analysis of large astronomical data sets. Gordon offers us a powerful platform for attacking these challenging computational problems.” The POLARBEAR project and successor project called The Simons Array, led by UC Berkeley and funded first by the Simons Foundation and then in 2015 by the NSF under a five-year, $5 million grant, will continue to use Gordon as a key resource. “POLARBEAR and The Simons Array, which will deploy the most powerful CMB (Cosmic Microwave Background) radiation telescope and detector system ever made, are two NSF supported astronomical telescopes that observe CMB, in essence the leftover ‘heat’ from the Big Bang in the form of microwave radiation,” said Brian Keating, a professor of physics at UC San Diego’s Center for Astrophysics & Space Sciences and a co-PI for the POLARBEAR/Simons Array project. “The POLARBEAR experiment alone collects nearly one gigabyte of data every day that must be analyzed in real time,” added Keating. “This is an intensive process that requires dozens of sophisticated tests to assure the quality of the data. Only by leveraging resources such as Gordon are we be able to continue our legacy of success.” Gordon also will be used in conjunction with the Simons Observatory, a 5-year $40 million project awarded by the Foundation in May 2016 to a consortium of universities led by UC San Diego, UC Berkeley, Princeton University, and the University of Pennsylvania. In the Simons Observatory, new telescopes will join the existing POLARBEAR/Simons Array and Atacama Cosmology Telescopes to produce an order of magnitude more data than the current POLARBEAR experiment. An all-hands meeting for the new project will take place at SDSC this summer. A video describing the project can be viewed by clicking the image below. The result of a five-year, $20 million NSF grant awarded in late 2009, Gordon entered production in early 2012 as one of the 50 fastest supercomputers in the world, and the first one to use massive amounts of flash-based memory. That made it many times faster than conventional HPC systems, while having enough bandwidth to help researchers sift through tremendous amounts of data. Gordon also has been a key resource within NSF’s XSEDE (Extreme Science and Engineering Discovery Environment) project. The system will officially end its NSF duties on March 31 following two extensions from the agency. By the end of February 2017, Gordon had supported research and education by more than 2,000 command-line users and over 7,000 gateway users, primarily through resource allocations from XSEDE. One of Gordon’s most data-intensive tasks was to rapidly process raw data from almost one billion particle collisions as part of a project to help define the future research agenda for the Large Hadron Collider (LHC). Gordon provided auxiliary computing capacity by processing massive data sets generated by one of the LHC’s two large general-purpose particle detectors used to find the elusive Higgs particle. The around-the-clock data processing run on Gordon was completed in about four weeks’ time, making the data available for analysis several months ahead of schedule.
News Article | April 28, 2017
IMAGE: The left figure shows the P-T pseudosection calculated for the representative tonalitic sample (J13). The melt compositions simulated for three isobaric melting processes under high, medium and low pressure conditions... view more The ancient continental crust in the earth was mainly formed in the Archean, 2.5~4.0 billion years ago, and is chiefly composed of tonalite, trondhjemite and granodiorite (TTG rocks). These three kinds of rock preserve pivotal information of the formation and evolution of early continental crust. Study on the petrogenesis of TTG rocks can provide great contributions to elucidate the tectonic regimes of the early earth. A latest research, using quantitative phase modeling approach to document the partial melting process of tonalitic gneiss, presents an innovative viewpoint of petrogenesis of Archean trondhjemite in the Eastern Hebei, China. Research paper titled: "Petrogenetic simulation of the Archean trondhjemite from Eastern Hebei China", is published in Science China Earth Sciences. The corresponding author is Professor Wei Chunjing, School of Earth and Space Sciences, Peking University. A forward method for studying the petrogenesis of granitoids is to use high-temperature and high-pressure experiments by selecting different bulk-rock compositions as starting materials and to compare the melts compositions experimentally constrained with those of real rocks. Results from previous experimental studies suggest that the Archean TTG rocks were formed by partial melting of hydrous mafic rocks, and low melting degrees or melting under high pressure conditions tend to produce trondhjemitic melt. Field observations in many Precambrian terrains shows that trondhjemite commonly occurs as small veins, intrusions and/or as leucosomes within tonalitic gneiss, being in-situ melting origin. This suggests that that trondhjemitic melt can be generated by partial melting of tonalitic rocks. Thus, a systematic research is implemented to simulate the origin of trondhjemite. Taking trondhjemitic rocks from the Eastern Hebei as an example, the authors present phase modeling for a representative tonalitic sample using recent internally consistent thermodynamic data set, available activity models of minerals and melt and the THERMOCALC software. On the basis of the calculated P-T pseudosection, melt compositions were constrained under different P-T conditions, and compared with those of trondhjemitic rocks in the Eastern Hebei. The simulation results show that melts generated under 0.9~1.1GPa/800~850?C with melting degree of 5~10wt.% are comparable with trondhjemitic rocks from the Eastern Hebei in both major and trace element compositions. In addition, zircon U-Pb isotopic dating reveals that the formation age of trondhjemitic veins in the Eastern Hebei is consistent with the metamorphic age of the country tonalitic gneiss, further supporting the viewpoint that trondhjemitic rocks can be formed by the partial melting of tonalitic rocks. Using quantitative phase modeling approach, we simulate partial melting of tonalite and propose a new view that trondhjemite can be a melting product of tonalite rather than only produced by partial melting of mafic rocks under high pressure conditions. This will be significant for elucidating the Archean tectonic regime for the formation of TTG rocks. Moreover, this study provides a new and effective method for documenting of the genesis of granitoids. This research was funded by the key project of National Natural Science Foundation of China (No. 41430207) See the article: ZHANG ShiWei, WEI ChunJing, DUAN ZhanZhan, 2017. Petrogenetic simulation of the Archean trondhjemite from Eastern Hebei, China. Science China Earth Sciences http://engine.
News Article | May 8, 2017
Our ever-changing sun continuously shoots solar material into space. The grandest such events are massive clouds that erupt from the sun, called coronal mass ejections, or CMEs. These solar storms often come first with some kind of warning -- the bright flash of a flare, a burst of heat or a flurry of solar energetic particles. But another kind of storm has puzzled scientists for its lack of typical warning signs: They seem to come from nowhere, and scientists call them stealth CMEs. Now, an international team of scientists, led by the Space Sciences Laboratory at University of California, Berkeley, and funded in part by NASA, has developed a model that simulates the evolution of these stealthy solar storms. The scientists relied upon NASA missions STEREO and SOHO for this work, fine-tuning their model until the simulations matched the space-based observations. Their work shows how a slow, quiet process can unexpectedly create a twisted mass of magnetic fields on the sun, which then pinches off and speeds out into space -- all without any advance warning. Compared to typical CMEs, which erupt from the sun as fast as 1800 miles per second, stealth CMEs move at a rambling gait -- between 250 to 435 miles per second. That's roughly the speed of the more common solar wind, the constant stream of charged particles that flows from the sun. At that speed, stealth CMEs aren't typically powerful enough to drive major space weather events, but because of their internal magnetic structure they can still cause minor to moderate disturbances to Earth's magnetic field. To uncover the origins of stealth CMEs, the scientists developed a model of the sun's magnetic fields, simulating their strength and movement in the sun's atmosphere. Central to the model was the sun's differential rotation, meaning different points on the sun rotate at different speeds. Unlike Earth, which rotates as a solid body, the sun rotates faster at the equator than it does at its poles. The model showed differential rotation causes the sun's magnetic fields to stretch and spread at different rates. The scientists demonstrated this constant process generates enough energy to form stealth CMEs over the course of roughly two weeks. The sun's rotation increasingly stresses magnetic field lines over time, eventually warping them into a strained coil of energy. When enough tension builds, the coil expands and pinches off into a massive bubble of twisted magnetic fields -- and without warning -- the stealth CME quietly leaves the sun. Such computer models can help researchers better understand how the sun affects near-Earth space, and potentially improve our ability to predict space weather, as is done for the nation by the U.S. National Oceanic and Atmospheric Administration. A paper published in the Journal of Geophysical Research on Nov. 5, 2016, summarizes this work.
Zhang G.,China University of Geosciences |
Zhang G.,University of Texas at San Antonio |
Zhang G.,East China Institute of Technology |
Xie H.,University of Texas at San Antonio |
And 4 more authors.
Remote Sensing of Environment | Year: 2011
In this study, ICESat altimetry data are used to provide precise lake elevations of the Tibetan Plateau (TP) during the period of 2003-2009. Among the 261 lakes examined ICESat data are available on 111 lakes: 74 lakes with ICESat footprints for 4-7. years and 37 lakes with footprints for 1-3. years. This is the first time that precise lake elevation data are provided for the 111 lakes. Those ICESat elevation data can be used as baselines for future changes in lake levels as well as for changes during the 2003-2009 period. It is found that in the 74 lakes (56 salt lakes) examined, 62 (i.e. 84%) of all lakes and 50 (i.e. 89%) of the salt lakes show tendency of lake level increase. The mean lake water level increase rate is 0.23. m/year for the 56 salt lakes and 0.27. m/year for the 50 salt lakes of water level increase. The largest lake level increase rate (0.80. m/year) found in this study is the lake Cedo Caka. The 74 lakes are grouped into four subareas based on geographical locations and change tendencies in lake levels. Three of the four subareas show increased lake levels. The mean lake level change rates for subareas I, II, III, IV, and the entire TP are 0.12, 0.26, 0.19, -0.11, and 0.2. m/year, respectively. These recent increases in lake level, particularly for a high percentage of salt lakes, supports accelerated glacier melting due to global warming as the most likely cause. © 2011 Elsevier Inc.
Xie H.,University of Texas at San Antonio |
Tekeli A.E.,University of Texas at San Antonio |
Tekeli A.E.,King Saud University |
Ackley S.F.,University of Texas at San Antonio |
And 2 more authors.
Journal of Geophysical Research: Oceans | Year: 2013
Sea ice thicknesses derived from NASA's Ice, Cloud, and Land Elevation Satellite (ICESat) altimetry data are examined using two different approaches, buoyancy and empirical equations, and at two spatial scales - ICESat footprint size (70 m diameter spot) and Advanced Microwave Scanning Radiometer (AMSR-E) pixel size (12.5 km by 12.5 km) for the Bellingshausen and Amundsen Seas of west Antarctica. Ice thickness from the empirical equation shows reasonable spatial and temporal distribution of ice thickness from 2003 to 2009. Ice thickness from the buoyancy equation, however, additionally needing snow depth information derived from the AMSR-E, shows an overestimation in terms of maximum, mean (+63% to 75%), and standard deviation while underestimation in modal thickness (-20%) as compared with those from the empirical equation approach. When ICESat snow freeboard is used as the snow depth in the buoyancy equation, i.e., the zero ice freeboard assumption, the derived ice thicknesses match well with those from the empirical equation approach, within 5% overall. The AMSR-E, therefore, may underestimate snow depth and accounts for ~95% of the ice thickness overestimation as compared with the buoyancy approach. The empirical equation derived ice thickness shows a consistent asymmetrical distribution with a long tail to high values, and seasonal median values ranging from 0.8 to 1.4 m over the 2003-2009 period that are always larger than the corresponding modal values (0.6-1.1 m) and lower than the mean values (1.0-1.6 m), with standard deviation of 0.6-1.0 m. An overall increasing trend of 0.03 m/year of mean ice thickness is found from 2003 to 2009, although statistically insignificant (p = 0.11) at the 95% confidence level. Starting from autumn, a general picture of seasonal mean, modal, and median ice thickness increases progressively from autumn to spring and decreases from spring to the following autumn, when new thin ice dominates the ice thickness distribution. The asymmetric shape of the thickness distribution reflects the key role of ice deformation processes in the evolution of the thickness distribution. The statistical properties of the thickness distribution interannually (high range of mean thickness and standard deviation) indicate the variability of deformation processes. However, spring ice volume, the product of ice mean thickness and areal extent computed for the spring maximum, shows variability year to year but is primarily dominated by ice extent variability, with no increasing or decreasing trend over this record length. The dependence of the volume on the ice extent primarily suggests that ice thickness changes have also not covaried with the ice extent losses seen over the satellite record in this region, unlike the Arctic. These properties reflect the interactive processes of ice advection, thermodynamic growth and ice deformation that all substantially influence ice mass balance in the Bellingshausen-Amundsen Seas region. ©2013. American Geophysical Union. All Rights Reserved.
Space Sciences Inc | Date: 2014-05-22
Athletic apparel, namely, shirts, pants, jackets, footwear, hats and caps, athletic uniforms; Golf shoes.
Space Sciences Inc | Date: 2014-05-22
Space Sciences Inc | Date: 2015-03-18
Clothing, namely, sweatpants, sweatshirts, fleece tops, fleece bottoms, coats, jackets, sweaters, shirts, pants, shorts, dresses, skirts, underwear, bathrobes, scarves, gloves, hats, socks, shoes, golf shoes, boots, slippers. Balls for games; balls for sports; bags especially adapted for sporting equipment, namely, golf bags; golf accessories, namely, golf clubs, golf club covers, golf ball dispensers, golf club heads, golf club inserts, golf club shafts, head covers for golf clubs, golf irons, hand grips for golf clubs, golf putters, golf putter covers, golf gloves, golf bag covers.