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  • richardmitnick 3:57 pm on August 15, 2016 Permalink | Reply
    Tags: , , Space Weather   

    From Goddard: “NASA’s Van Allen Probes Catch Rare Glimpse of Supercharged Radiation Belt” 

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    NASA Goddard Space Flight Center

    Aug. 15, 2016
    Lina Tran
    NASA’s Goddard Space Flight Center, Greenbelt, Md.

    Our planet is nestled in the center of two immense, concentric doughnuts of powerful radiation: the Van Allen radiation belts, which harbor swarms of charged particles that are trapped by Earth’s magnetic field. On March 17, 2015, an interplanetary shock – a shockwave created by the driving force of a coronal mass ejection, or CME, from the sun – struck Earth’s magnetic field, called the magnetosphere, triggering the greatest geomagnetic storm of the preceding decade.

    Magnetosphere of Earth, original bitmap from NASA. SVG rendering by Aaron Kaase
    Magnetosphere of Earth, original bitmap from NASA. SVG rendering by Aaron Kaase

    And NASA’s Van Allen Probes were there to watch the effects on the radiation belts.

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    Artist concept of accelerated electrons circulating in Earth’s Van Allen radiation belts. Credits: NASA’s Goddard Space Flight Center; Tom Bridgman, animator

    NASA Van Allen Probes


    On March 17, 2015, an interplanetary shock – a shockwave created by the driving force of a coronal mass ejection, or CME, from the sun – struck the outermost radiation belt, triggering the greatest geomagnetic storm of the preceding decade. NASA’s Van Allen Probes were there to watch it. Credits: NASA’s Goddard Space Flight Center; Genna Duberstein, producer

    One of the most common forms of space weather, a geomagnetic storm describes any event in which the magnetosphere is suddenly, temporarily disturbed. Such an event can also lead to change in the radiation belts surrounding Earth, but researchers have seldom been able to observe what happens. But on the day of the March 2015 geomagnetic storm, one of the Van Allen Probes was orbiting right through the belts, providing unprecedentedly high-resolution data from a rarely witnessed phenomenon. A paper on these observations was published in the Journal of Geophysical Research on Aug. 15, 2016.

    Researchers want to study the complex space environment around Earth because the radiation and energy there can impact our satellites in a wide variety of ways – from interrupting onboard electronics to increasing frictional drag to disrupting communications and navigation signals.

    “We study radiation belts because they pose a hazard to spacecraft and astronauts,” said David Sibeck, the Van Allen Probes mission scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who was not involved with the paper. “If you knew how bad the radiation could get, you would build a better spacecraft to accommodate that.”

    Studying the radiation belts is one part of our efforts to monitor, study and understand space weather. NASA launched the twin Van Allen Probes in 2012 to understand the fundamental physical processes that create this harsh environment so that scientists can develop better models of the radiation belts. These spacecraft were specifically designed to withstand the constant bombardment of radiation in this area and to continue to collect data even under the most intense conditions. A set of observations on how the radiation belts respond to a significant space weather storm, from this harsh space environment, is a goldmine.

    The recent research describes what happened: The March 2015 storm was initiated by an interplanetary shock hurtling toward Earth – a giant shockwave in space set off by a CME, much like a tsunami is triggered by an earthquake.

    Swelling and shrinking in response to such events and solar radiation, the Van Allen belts are highly dynamic structures within our planet’s magnetosphere. Sometimes, changing conditions in near-Earth space can energize electrons in these ever-changing regions. Scientists don’t yet know whether energization events driven by interplanetary shocks are common. Regardless, the effects of interplanetary shocks are highly localized events – meaning if a spacecraft is not precisely in the right place when a shock hits, it won’t register the event at all. In this case, only one of the Van Allen Probes was in the proper position, deep within the magnetosphere – but it was able to send back key information.

    The spacecraft measured a sudden pulse of electrons energized to extreme speeds – nearly as fast as the speed of light – as the shock slammed the outer radiation belt. This population of electrons was short-lived, and their energy dissipated within minutes. But five days later, long after other processes from the storm had died down, the Van Allen Probes detected an increased number of even higher energy electrons. Such an increase so much later is a testament to the unique energization processes following the storm.

    “The shock injected – meaning it pushed – electrons from outer regions of the magnetosphere deep inside the belt, and in that process, the electrons gained energy,” said Shri Kanekal, the deputy mission scientist for the Van Allen Probes at Goddard and the leading author of a paper on these results.

    Researchers can now incorporate this example into what they already know about how electrons behave in the belts, in order to try to understand what happened in this case – and better map out the space weather processes there. There are multiple ways electrons in the radiation belts can be energized or accelerated: radially, locally or by way of a shock. In radial acceleration, electrons are carried by low-frequency waves towards Earth. Local acceleration describes the process of electrons gaining energy from relatively higher frequency waves as the electrons orbit Earth. And finally, during shock acceleration, a strong interplanetary shock compresses the magnetosphere suddenly, creating large electric fields that rapidly energize electrons.

    Scientists study the different processes to understand what role each process plays in energizing particles in the magnetosphere. Perhaps these mechanisms occur in combination, or maybe just one at a time. Answering this question remains a major goal in the study of radiation belts – a difficult task considering the serendipitous nature of the data collection, particularly in regard to shock acceleration.

    Additionally, the degree of electron energization depends on the process that energizes them. One can liken the process of shock acceleration, as observed by the Van Allen Probe, to pushing a swing.

    “Think of ‘pushing’ as the phenomenon that’s increasing the energy,” Kanekal said. “The more you push a swing, the higher it goes.” And the faster electrons will move after a shock.

    In this case, those extra pushes likely led to the second peak in high-energy electrons. While electromagnetic waves from the shock lingered in the magnetosphere, they continued to raise the electrons’ energy. The stronger the storm, the longer such waves persist. Following the March 2015 storm, resulting electromagnetic waves lasted several days. The result: a peak in electron energy measured by the Van Allen Probe five days later.

    This March 2015 geomagnetic storm was one of the strongest yet of the decade, but it pales in comparison to some earlier storms. A storm during March 1991 was so strong that it produced long-lived, energized electrons that remained within the radiation belts for multiple years. With luck, the Van Allen Probes may be in the right position in their orbit to observe the radiation belt response to more geomagnetic storms in the future. As scientists gather data from different events, they can compare and contrast them, ultimately helping to create robust models of the little-understood processes occurring in these giant belts.

    The Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, built and operates the Van Allen Probes for NASA’s Heliophysics Division in the Science Mission Directorate. The Van Allen Probes are the second mission in NASA’s Living With a Star program, an initiative managed by Goddard and focused on aspects of the sun-Earth system that directly affect human lives and society.

    Related Links

    Van Allen Probes Mission Overview
    NASA’s Van Allen Probes Spot an Impenetrable Barrier in Space
    NASA’s Van Allen Probes Revolutionize View of Radiation Belts

    See the full article here.

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    NASA’s Goddard Space Flight Center is home to the nation’s largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

    Named for American rocketry pioneer Dr. Robert H. Goddard, the center was established in 1959 as NASA’s first space flight complex. Goddard and its several facilities are critical in carrying out NASA’s missions of space exploration and scientific discovery.

    NASA Goddard Campus
    NASA/Goddard Campus
    NASA

     
  • richardmitnick 11:21 am on August 4, 2016 Permalink | Reply
    Tags: , , Space Weather   

    From Eos: “Predicting Space Weather, Protecting Satellites” 

    Eos news bloc

    Eos

    8.4.16
    Leah Crane

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    Blue and red dots denote the geographic locations of selected satellites above Earth in a geosynchronous orbit. Charged particles in Earth’s magnetosphere can affect the operations of these spacecraft, especially when they arrive without warning. Credit: Denton et al. [2016]

    Magnetosphere of Earth, original bitmap from NASA. SVG rendering by Aaron Kaase
    Magnetosphere of Earth, original bitmap from NASA. SVG rendering by Aaron Kaase

    The Earth is surrounded by a collection of communications, scientific, and military satellites, many in geosynchronous orbit (GEO), meaning they remain at the same geographic spot above Earth as they orbit and the planet rotates. As they whizz around the planet’s satellite superhighway, they are bombarded with charged particles. Because the onslaught of electrons and ions in orbit can damage or even disable satellites over time, understanding the conditions at GEO can give spacecraft designers and operators information that could be used to mitigate negative effects on satellites.

    A new study by Denton et al. presents a new model capable of predicting electron and ion fluxes at GEO with an hour of lead time, allowing satellite operators to take advanced action to protect satellites. The model is based on electron and ion flux observations made between 1989 and 2007 by Magnetospheric Plasma Analyzer (MPA) instruments from the Los Alamos National Laboratory aboard several geostationary spacecraft. Those instruments provide a set of three-dimensional data cubes, including electron energy, local time, and properties of the solar wind (the product of its speed and magnetic field). Using those three values, the model provided by the researchers returns a prediction of the electron and ion flux at GEO.

    Previous models used the planetary Kp index, which measures disturbances in Earth’s magnetic field in real time, rather than measurements of the solar wind. The Kp index has drawbacks, however: It is updated every 3 hours, for example, but electron and ion fluxes at GEO often fluctuate much more rapidly. Although the model presented here yielded results equivalent to models that use the Kp index, future versions will include even more data, such as past conditions in the magnetosphere and the time it takes for the solar wind to reach locations in GEO. For scientists who use fluxes at GEO to define boundary conditions for models of the inner magnetosphere, future capabilities for more precise measurements could improve modeling capabilities.

    Also, measurements of the Kp index reflect the current conditions, making it impossible for satellite operators to take action to protect their instrumentation ahead of time. The solar wind, on the other hand, can be measured by satellites an hour “upstream” of the Earth. In providing robust electron flux and ion flux results that are comparable in accuracy to previous models but with an hour of lead time, the authors take a step toward both better models of Earth’s magnetosphere and better protection for satellites. The model is freely available for download.

    See the full article here .

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    Eos is the leading source for trustworthy news and perspectives about the Earth and space sciences and their impact. Its namesake is Eos, the Greek goddess of the dawn, who represents the light shed on understanding our planet and its environment in space by the Earth and space sciences.

     
  • richardmitnick 11:03 am on August 3, 2016 Permalink | Reply
    Tags: , CASSIOPE, CSA, , Space Weather   

    From Eos: “Tracking Ions at the Edge of the Atmosphere” 

    Eos news bloc

    Eos

    2 August 2016
    Leah Crane

    1
    The research satellite CASSIOPE on a test platform at the Canadian Space Agency’s David Florida Laboratory. CASSIOPE hosts the GPS Attitude, Positioning, and Profiling instrument designed by GGE researchers. The four white antennas on the left-facing side of the spacecraft will be used to determine the position, velocity, and attitude of the spacecraft while the antenna on the upper side will be used to profile the ionosphere’s electron density. (Photograph courtesy of MacDonald, Dettwiler and Associates Ltd.)

    The border between Earth and space is a turbulent one: Ions from the solar wind and other forms of space weather batter Earth’s atmosphere, which is constantly churning and slowly leaking away into space. Solar storms in particular whip the upper atmosphere into a frenzy, with potentially devastating effects on space-based technologies like GPS navigation and radio communication.

    To better understand how space weather and solar storms interact with Earth’s upper atmosphere, the Canadian Space Agency launched the Cascade, Smallsat and Ionospheric Polar Explorer (CASSIOPE) satellite in 2013. The Enhanced Polar Outflow Probe (e-POP), one of two payloads aboard CASSIOPE, holds a suite of eight scientific instruments, all studying different aspects of near-Earth space. Here Yau and Howarth present the first scientific results from one of those instruments, the imaging and rapid-scanning ion mass spectrometer (IRM).

    The IRM takes samples of ions from Earth’s ionosphere and magnetosphere and identifies the energy-to-charge ratio (E/q) and mass-to-charge ratio (M/q) of each ion, as well as the angle from which it approached the satellite. As ions approach the IRM, a time-of-flight gate opens and closes rapidly to control the flow of ions entering the apparatus, selecting for specific M/q values. Then, a hemispherical electrostatic analyzer uses an electric field to disperse the ions onto an array of 64 detector pixels according to their E/q and angle of approach.

    Using data collected by the IRM, the researchers were able to determine what sorts of ions were observed and the energies of those ions. There was some uncertainty because of overlaps in the possible values for various types of ions: singly charged cations of nitrogen (N+) and oxygen (O+), for example, have very similar atomic masses, which makes them difficult to separate when both land on the same detector pixel.

    Despite that uncertainty, the authors found high densities of heavy “minor” doubly charged oxygen cations (O2+), N+, and molecular ions at the upper edge of Earth’s ionosphere. These heavy ions, particularly N+, play an important role in atmospheric escape over long time scales. Therefore, not only will e-POP’s study of space weather provide insight into the types of ions energized by solar storms, but it could also help researchers understand the long-term evolution of the Earth’s atmosphere. (Journal of Geophysical Research: Space Physics, doi:10.1002/2016JA022699, 2016)

    See the full article here .

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    Eos is the leading source for trustworthy news and perspectives about the Earth and space sciences and their impact. Its namesake is Eos, the Greek goddess of the dawn, who represents the light shed on understanding our planet and its environment in space by the Earth and space sciences.

     
  • richardmitnick 4:06 pm on February 10, 2016 Permalink | Reply
    Tags: , , , , , Owens Valley Long Wavelength Array, , Space Weather   

    From Caltech: “Chasing Extrasolar Space Weather” 

    Caltech Logo
    Caltech

    02/10/2016
    Lori Dajose

    Earth’s magnetic field acts like a giant shield, protecting the planet from bursts of harmful charged solar particles that could strip away the atmosphere.

    Magnetosphere of Earth
    Earth’s magnetosphere

    Gregg Hallinan, an assistant professor of astronomy, aims to detect this kind of space weather on other stars to determine whether planets around these stars are also protected by their own magnetic fields and how that impacts planetary habitability.

    On Wednesday, February 10, at 8 p.m. in Beckman Auditorium, Hallinan will discuss his group’s efforts to detect intense radio emissions from stars and their effects on any nearby planets. Admission is free.

    What do you do?
    I am an astronomer. My primary focus is the study of the magnetic fields of stars, planets, and brown dwarfs—which are kind of an intermediate object between a planet and a star.

    Brown dwarf
    Brown dwarf

    Stars and their planets have intertwined relationships. Our sun, for example, produces coronal mass ejections, or CMEs, which are bubbles of hot plasma explosively ejected from the sun out into the solar system.

    Solar eruption 2012 by NASA's Solar Dynamic Observatory SDO
    CME

    Radiation and particles from these solar events bombard the earth and interact with the atmosphere, dominating the local “space weather” in the environment of Earth. Happily, our planet’s magnetic field shields and redirects CMEs toward the polar regions. This causes auroras—the colorful light in the sky commonly known as the Northern or Southern Lights.

    Auroras from around the world
    Auroras from around the world

    Our new telescope, the Owens Valley Long Wavelength Array, images the entire sky instantaneously and allows us to monitor extrasolar space weather on thousands of nearby stellar systems.

    Caltech Owens Valley Long Wavelength Array
    Caltech Owens Valley Long Wavelength Array

    When a star produces a CME, it also emits a bright burst of radio waves with a specific signature. If a planet has a magnetic field and it is hit by one of these CMEs, it will also become brighter in radio waves. Those radio signatures are very specific and allow you to measure very precisely the strength of the planet’s magnetic field. I am interested in detecting radio waves from exoplanets—planets outside of our solar system—in order to learn more about what governs whether or not a planet has a magnetic field.

    Why is this important?

    The presence of a magnetic field on a planet can tell us a lot. Like on our own planet, magnetic fields are an important line of defense against the solar wind, particularly explosive CMEs, which can strip a planet of its atmosphere. Mars is a good example of this. Because it didn’t have a magnetic field shielding it from the sun’s solar wind, it was stripped of its atmosphere long ago. So, determining whether a planet has a magnetic field is important in order to determine which planets could possibly have atmospheres and thus could possibly host life.

    How did you get into this line of work?

    From a young age, I was obsessed with astronomy—it’s all I cared for. My parents got me a telescope when I was 7 or 8, and from then on, that was it.

    As a grad student, I was looking at magnetic fields of cool—meaning low-temperature—objects. When I was looking at brown dwarfs, I found that they behave like planets in that they also have auroras. I had the idea that auroras could be the avenue to examine the magnetic fields of other planets. So brown dwarfs were my gateway into exoplanets.

    See the full article here .

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    The California Institute of Technology (commonly referred to as Caltech) is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. “The mission of the California Institute of Technology is to expand human knowledge and benefit society through research integrated with education. We investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”
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  • richardmitnick 12:12 pm on September 29, 2015 Permalink | Reply
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    From LANL: “Model predicts space weather and protects satellite hardware” 

    LANL bloc

    Los Alamos National Laboratory

    September 28, 2015
    Communications Office
    (505) 667-7000

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    Approximate location of geosynchronous orbit spacecraft — projected to the Earth’s equator.

    Researchers used 82 satellite-years of observations from the Magnetospheric Plasma Analyzer instruments aboard Los Alamos National Laboratory satellites at geosynchronous orbit to create a comprehensive model of how plasma behaves in this region of Earth’s magnetosphere — the most heavily populated orbit for spacecraft traffic. The journal Space Weather published the work, and the American Geophysical Union newsmagazine Eos highlighted it as a Research Spotlight. Knowledge and prediction of the environment at geosynchronous orbit is crucial for spacecraft designers and operators because changes in the plasma environment, caused by the Sun and its solar wind, can interfere with satellite functioning and even lead to satellite failure.

    Significance of the research

    Geosynchronous orbit — roughly 36,000 kilometers above Earth’s surface — is one of the most popular locations for military, scientific, and communications satellites. The 24-hour orbital period at geosynchronous orbit ensures that satellites maintain a fixed location in Earth’s sky. This area marks the approximate boundary between Earth’s inner and outer magnetosphere, where electromagnetic forces from the two regions control electrically charged particles (electrons and ions) known as plasma.

    Current models of this environment focus on predicting how fluxes of energetic ions and electrons, which can cause a buildup of charge on spacecraft materials, will affect satellite systems. The new research provides a more comprehensive picture by examining how factors such as solar wind and geomagnetic activity can influence these fluxes in plasma.

    The researchers created a model that can predict the plasma flux environment at geosynchronous orbit in response to rapid changes in geomagnetic and solar activity. The model predicts the fluxes that can cause a buildup of charge on spacecraft materials over a range of energies and time. The new model provides scientific and operational users with prediction of fluxes over a wider range of conditions than is generally the case with current models. As the model matures, the researchers plan to extend the analysis to predict hazardous fluxes as a function of solar wind speed and magnetic field orientation. These are critical factors that control plasma fluxes at geosynchronous orbit. The model will be useful for satellite operators because more than 400 satellites currently reside in geosynchronous orbit.
    Research achievements

    The team analyzed the largest existing dataset of electron and ion fluxes. The Magnetospheric Plasma Analyzer instruments on board Los Alamos National Laboratory satellites collected the data over 17 years and one and a half solar cycles. The researchers combined the data sets from seven satellites (a total of 82 satellite-years of data) with observations on solar and geomagnetic activity. They developed a comprehensive model of the flux of electrons and ions at geosynchronous orbit as a function of local time, energy, geomagnetic activity, and solar activity for energies between approximately 1 eV and approximately 40 keV. This energy range encompasses the plasmasphere, the electron plasma sheet, the ion plasma sheet and the substorm-injected suprathermal tails of both the electron and ion plasma sheets. Satellites on station at geosynchronous orbit encounter each of these populations regularly.

    The team validated the model by comparing its predictions with spacecraft data that another set of satellites collected during a five-day period of both calm and active space weather. As the model matures, the researchers plan to extend the analysis to predict hazardous fluxes as a function of solar wind speed and magnetic field orientation. These are critical factors that control plasma fluxes at geosynchronous orbit. The team has made a beta version of the model freely available.
    The research team

    The researchers include M. H. Denton of LANL’s Space Science Institute, M. F. Thomsen, V. K. Jordanova, M. G. Henderson and J. E. Borovsky of LANL’s Space Science and Applications group; J. S. Denton of Sellafield Ltd. (now of Nuclear and Radiochemistry, C-NR); D. Pitchford of SES Engineering; and D. P. Hartley of Lancaster University.

    The Los Alamos Laboratory Directed Research and Development (LDRD) program funded the research through the SHIELDS project, which aims to understand, model, and predict Space Hazards Induced near Earth by Large, Dynamic Storms (SHIELDS). This work supports the Lab’s Global Security mission area for space situational awareness and the Science of Signatures science pillar.

    See the full article here .

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    Los Alamos National Laboratory’s mission is to solve national security challenges through scientific excellence.

    LANL campus
    Los Alamos National Laboratory, a multidisciplinary research institution engaged in strategic science on behalf of national security, is operated by Los Alamos National Security, LLC, a team composed of Bechtel National, the University of California, The Babcock & Wilcox Company, and URS for the Department of Energy’s National Nuclear Security Administration.

    Los Alamos enhances national security by ensuring the safety and reliability of the U.S. nuclear stockpile, developing technologies to reduce threats from weapons of mass destruction, and solving problems related to energy, environment, infrastructure, health, and global security concerns.

    Operated by Los Alamos National Security, LLC for the U.S. Dept. of Energy’s NNSA

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  • richardmitnick 8:47 am on September 23, 2015 Permalink | Reply
    Tags: BALLOON Project, , Space Weather   

    From The Conversation: “Scientists at work: space balloons and charged particles above the Arctic Circle” 

    Conversation
    The Conversation

    September 18, 2015
    Alexa Halford

    1
    Launching a space balloon in Sweden. Alexa Halford, CC BY-ND

    I research space weather. That’s how physicists describe how storms on the sun end up affecting us here on Earth. Most days I sit at a computer coding, attending telephone conference meetings with collaborators across the country and meeting with fellow space physicists. But sprinkled throughout the year I get to do exciting fieldwork in remote locations. We launch high-tech space balloons in an effort to help untangle what happens when charged particles from solar storms hit the Earth’s magnetic field, called its magnetosphere.

    2
    Events on the sun can change conditions in near-Earth space. NASA, CC BY

    I primarily work with the Balloon Array for Radiation-belt Relativistic Electron Losses (BARREL) mission, led by Robyn Millan here at Dartmouth College. We’re investigating the electrons and protons that travel all the way from the sun and then get trapped in the Earth’s magnetic field. Often they stick around, just bouncing and drifting along in our planet’s so-called radiation belts – these are donut-shaped regions rich in charged particles, held in place around Earth by its magnetic field.


    It’s a team effort to unravel how space weather works – and affects us.
    Download the mp4 video here.

    But during a geomagnetic storm, changes in the Earth’s magnetic field can accelerate and transport these electrons and protons. They can wind up getting “lost”: shot out of the radiation belts back into space or down into our atmosphere. If they start colliding with neutral, uncharged particles in the atmosphere, that can affect upper atmospheric chemistry – and be bad news for our technology down here on Earth. For example, geomagnetic storms can cause blackouts, increased corrosion in pipelines, destruction of satellites and a resulting loss of communication connections.

    My colleagues and I focus on the radiation belt electrons that get lost to the Earth’s atmosphere. If we can unravel more about what’s happening with them, the hope is we can figure out how to better predict space weather – and its effects on terrestrial weather. Ultimately, with better understanding of what’s going on, we can work on protecting our technology from these geomagnetic squalls.


    What is a magnetic field?
    Download the mp4 video here.

    Magnets all around us

    You can think of the Earth as a big bar magnet, like the kind you might have had in your elementary school classroom. You’re probably familiar with magnets’ attractive and repulsive properties. Around a bar magnet, iron shavings trace out what we can think of as lines of magnetic field.

    Protons and electrons trapped in Earth’s magnetosphere follow these same kinds of lines, converging at the poles. Typically the particles just gyrate and bounce along these lines, happily drifting around the Earth in those radiation belts.

    Since space is so big, and the density of particles is so small, they can usually travel without bumping into each other. But during geomagnetic activity – like a storm in space – the particles can get pushed farther down the field line, closer to the Earth. In a process similar to what creates the auroras, they start colliding with the denser atmosphere. And this is when some of the charged particles wind up “lost” from the radiation belts.

    What happens to the “lost” particles that seem to disappear in the atmosphere, and why? To answer these questions, we travel to the polar regions to collect data.

    3
    Launch of BARREL payload 3B from the SSC’s ESRANGE. Alexa Halford

    Polar hunt for solar particles

    This year we headed 90 miles above the Arctic Circle to the Swedish Space Corporation’s ESRANGE to launch our space balloons. Our goal is to send the balloons up as far as 22 miles (35 km) into the stratosphere to measure X-rays during a geomagnetic storm; since X-rays are created when electrons from the radiation belts interact with uncharged particles in the atmosphere, we can use them to infer when electrons are lost.

    4
    BARREL payload. Alexa

    Each balloon carries a payload of scientific equipment. A scintillator counts X-rays. A magnetometer measures the magnetic field of the Earth. Each payload and balloon has its own GPS tracker.

    During our last campaigns in Antarctica, we were flying during a period of circumpolar winds that blow long and hard in a circle around the poles. This allowed our 300,000-cubic-foot balloons to stay up, on average, for 12 days. This year in Sweden, though, we flew during a period called “turnaround,” when the stratospheric winds are changing direction, and our flights were lucky to last even four hours.


    BARREL balloons fly in Antarctica.
    Download the mp4 video here.

    When the balloon either starts falling below an altitude of 13.6 miles (22 km), or starts moving toward too densely populated regions, we have to terminate – that is, pop – the balloon. The balloon and the payload then separately fall back to Earth.

    6
    Retrieval of the balloon from the launch of BARREL payload 3C. It was a short 500 meters from the road and less than an hour drive from ESRANGE. Alexa Halford

    When our BARREL balloons flew in Antarctica, we weren’t able to recover most of them because the terrain was so difficult to cross. This year in Sweden we were able to recover all the payloads. When they came down close to the launch base, we drove out and hiked through bogs and woods to retrieve payloads and balloons.

    7
    We spotted the payload and its orange parachute via helicopter before finding and retrieving it and its balloon. Alexa Halford

    When they flew a bit farther away (like into Norway or Finland), we had to rent a helicopter to travel out and pick them up.

    During the campaign, when we’re launching the balloons, we’re in constant contact with the instrument teams on NASA’s Van Allen Probes as well as other satellite missions. We work together, trying to predict when satellites will be lined up along the same magnetic field lines with the balloons. That way we can look at high-resolution data the satellites are collecting in space on the same magnetic field lines at the same time our balloons are flying. We want to make links between space conditions and our X-ray readings, which stand in for how many electrons are being lost to the atmosphere.

    8
    Conjunctions between the BARREL balloons and satellites. The green lines marked ‘B-field’ show magnetic field lines. Alexa Halford

    Using our data to fill in what we know

    There’s still a lot to do once we wrap up the campaign and head home with our new data – the measurements taken in the magnetosphere during what are essentially space hurricanes. It takes plenty of ingenuity to translate the raw data into scientific understanding, and we have to do a lot of processing and analyzing.

    Our “lost” electrons interact with neutral particles in the atmosphere, producing the X-rays our balloons measure. The X-rays let us infer the energy of electrons we’re interested in. We combine our BARREL observations with those of satellites and other ground-based instruments to sort out how much energy the “lost” electrons had before they were lost. No single data set gives us the full picture, so we have to collaborate, fitting each piece of the puzzle together.


    The size and number of particles in the radiation belts can change drastically over short periods of time.
    Download the mp4 video here.

    Knowing how much energy the electron had before it got lost to the atmosphere, how large a region this phenomenon occurs over and how frequently this occurs gives us a better understanding of how the radiation belts work.

    8
    Sometimes science is done at a coffee shop, where you can find me writing up the next set of papers from our last campaign. Alexa Halford

    This fall, we’re starting to write up papers and put together presentations about our research to share with colleagues. We were incredibly lucky with this campaign. Every balloon that we sent up got some amazing data! Here’s hoping we’re one step closer to understanding the dynamics of the Earth’s radiation belts.

    See the full article here .

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    The Conversation US launched as a pilot project in October 2014. It is an independent source of news and views from the academic and research community, delivered direct to the public.
    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.
    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

     
  • richardmitnick 9:24 am on March 12, 2015 Permalink | Reply
    Tags: , , , Space Weather   

    From NASA Goddard: “MMS: Studying Magnetic Reconnection Near Earth” 

    NASA Goddard Banner

    Goddard Space Flight Center

    March 10, 2015

    The Magnetospheric Multiscale, or MMS, mission is scheduled to launch into space on March 12, 2015. The mission consists of four spacecraft to observe a phenomenon called magnetic reconnection — which doesn’t happen naturally on Earth all that often, but is a regular occurrence in space. At the heart of magnetic reconnection is a fundamental physics process in which magnetic field lines come together and explosively realign, often sending the particles in the area flying off near the speed of light.

    NASA MMS
    MMS spacecraft stacked with fairing open.

    The process may sound a bit abstract, but it is at the heart of some very concrete events in space. Take, for example, a giant explosion on the sun that occurred on July 12, 2012, causing colorful aurora and space weather near Earth a few days later. Magnetic reconnection catalyzed numerous events along the way.

    It all began at 12:11 p.m. EDT on July 12, 2012, when magnetic reconnection in the sun’s atmosphere, the corona, led to a solar flare. Scientists don’t yet know exactly what sets off one of these gigantic explosions of light and x-rays, but they know that magnetic reconnection – initiated in areas of complex and intense magnetic fields on the sun — is ultimately responsible.

    1
    Solar flares – such as this one captured by NASA’s SDO on July 12, 2012, are initiated by a phenomenon called magnetic reconnection. Image Credit: NASA/SDO

    NASA Solar Dynamics Observatory
    NASA/SDO

    Solar eruptions such as flares often occur in conjunction with a different kind of explosion that is also a consequence of reconnection called a coronal mass ejection, or CME. CMEs are giant clouds of solar material that erupt upward fast enough to achieve escape velocity and zoom out into space.

    2
    Solar eruptive events caused by magnetic reconnection on the sun can lead to giant ejections of solar material, called coronal mass ejections. This one, as observed by the joint ESA/NASA Solar and Heliospheric Observatory, traveled through space toward Earth in July 2012. Image Credit: ESA&NASA/SOHO

    NASA SOHO
    NASA/ESA SOHO

    On July 12, that CME sped out from the sun with an initial velocity of 850 miles per second and headed straight toward Earth, as can be seen in this simulation of the CME created with a model, called an Enlil model, via the Community Coordinated Modeling Center at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

    4
    A graph of data from NASA’s Advanced Composition Explorer shows how magnetic fields are aligned just outside Earth’s protective magnetic bubble, the magnetosphere. When below zero, as it was July 15-16, 2012, the graph indicates potential for magnetic reconnection and increased space weather.
    Image Credit: NASA/ACE

    The material in a CME is made of very hot, charged particles, also known as plasma. This plasma carries embedded magnetic fields along for the ride. On July 14, 2012 at around 2 p.m. EDT, after traveling for two days, those magnetic field lines collided with the magnetic field that naturally surrounds Earth, a giant bubble called the magnetosphere where it soon experienced another bout of magnetic reconnection.

    The magnetosphere’s field lines naturally point from Earth’s south magnetic pole to its north pole. Sometimes, the magnetic field lines inside a CME are pointed in the same direction and the collision is a reasonably gentle one: Solar material from the CME is rebuffed, and the magnetosphere itself doesn’t feel much effect.

    But this was not the case for this CME. The magnetic field lines in the plasma were pointed in the opposite direction of the field’s lines around Earth – as can be seen in this graph from NASA’s Advanced Composition Explorer, or ACE, which sits 1 million miles closer to the sun than Earth, just outside our magnetosphere. This type of graph from ACE shows just how much of a north/south magnetic field component is present at any given time. Above the midline, the graph shows magnetic fields that point north like Earth’s do; below the midline indicates magnetic fields that point south. Note, in this case, the extended period of strong southward magnetic field on July 15 and 16. Over and over during this time period, whenever the CME’s oppositely directed magnetic fields collided with Earth’s magnetospheric lines, magnetic reconnection occurred right at the boundary of the magnetosphere.

    NASA ACE Advanced Composition Explorer
    NASA/ACE

    5
    Viewed as if looking down from the top of the sun, this model – called an Enlil model – shows how a coronal mass ejection, or CME, traveled from the sun toward Earth July 12-15, 2012. Magnetic reconnection events occurring as the CME arrived at Earth set up space weather in near-Earth space.
    Image Credit: NASA/Goddard/CCMC/Bridgman

    During this period of repeated magnetic reconnection, surges of solar material breached the magnetosphere, zooming into near-Earth space. In this visualization of the magnetosphere, you can see how the magnetic fields lines at the front of the magnetosphere realign, peeling back like layers of an onion. As more lines are peeled back, more energy is dumped in the tail end of the magnetosphere, the magnetotail, giving rise to what’s called a geomagnetic storm.


    A visualization of Earth’s magnetosphere on July 15-16, 2012, shows how constant magnetic reconnection caused by an arriving coronal mass ejection, or CME, from the sun disrupted the magnetosphere, causing a geomagnetic storm.
    Image Credit: NASA/CCMC/Bridgman

    This visualization shows how excited the magnetosphere became after the CME passed by. Such space weather events can compress the front of the magnetosphere so satellites are left exposed to the more harsh radiation outside the magnetosphere. The magnetic variation can also initiate electric currents flowing through grid lines on Earth, with the potential to damage transformers and disrupt utility power grids.

    In the visualization, you can also see field lines connecting and realigning on the right side of Earth, in the magnetotail. As the magnetotail gets increasingly unstable, we see additional examples of magnetic reconnection. The reconnection events sent particles shooting off down the tail, and also toward Earth, where they collided with particles in the atmosphere to create aurora. This image shows the red purple aurora that occurred in Missouri on July 15, 2012.

    6
    An aurora in the early hours of July 15, 2012, seen in Albany, Missouri shows a colorful result of magnetic reconnection.
    Image Credit: Courtesy of Dan Bush

    The orbit for MMS will carry it through the magnetic reconnection at the nose of the magnetosphere for over a year, and then switch to flying through areas of magnetic reconnection in the magnetotail. MMS will offer us our first ever three-dimensional view of this process as it is happening, which will provide unprecedented amounts of information to help scientists better understand what sets it off and what effects it causes near Earth. Groups like NASA’s Community Coordinated Modeling Center can then take that information to improve models such as those seen here, which can be used by NOAA’s Space Weather Prediction Center — the U.S. government’s official source for space weather forecasts, alerts, watches and warnings – uses to forecast space weather.

    MMS is the fourth NASA Solar Terrestrial Probes Program mission. NASA Goddard built, integrated, and tested the four MMS spacecraft and is responsible for overall mission management and mission operations. The Southwest Research Institute in San Antonio, Texas, leads the Instrument Suite Science Team. Science operations planning and instrument command sequence development will be performed at the MMS Science Operations Center at the University of Colorado’s Laboratory for Atmospheric and Space Physics in Boulder. 


    See the full article here.

    Please help promote STEM in your local schools.

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    NASA’s Goddard Space Flight Center is home to the nation’s largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

    Named for American rocketry pioneer Dr. Robert H. Goddard, the center was established in 1959 as NASA’s first space flight complex. Goddard and its several facilities are critical in carrying out NASA’s missions of space exploration and scientific discovery.

    NASA Goddard Campus
    NASA/Goddard Campus
    NASA

     
  • richardmitnick 4:54 pm on December 10, 2014 Permalink | Reply
    Tags: , , , , , , Space Weather   

    From NASA Goddard: MMS Mission 

    NASA Goddard Banner

    Scientists Michael Hesse and John Dorelli explain the science objectives of the MMS mission.

    The [NASA] Magnetospheric Multiscale (MMS) mission is comprised of four identically instrumented spacecraft that will use Earth’s magnetosphere as a laboratory to study the microphysics of three fundamental plasma processes: magnetic reconnection, energetic particle acceleration, and turbulence. These processes occur in all astrophysical plasma systems but can be studied in situ only in our solar system and most efficiently only in Earth’s magnetosphere, where they control the dynamics of the geospace environment and play an important role in the processes known as “space weather.”

    Learn more about MMS at http://www.nasa.gov/mms

    Watch, enjoy, learn.

    4
    All four MMS spacecraft are stacked and ready for transport to the vibration chamber for environmental tests. Although they will be disassembled again later this month, this image is a sneak preview of what will be the final flight configuration of the MMS fleet.

    See the full article here.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    NASA’s Goddard Space Flight Center is home to the nation’s largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

    Named for American rocketry pioneer Dr. Robert H. Goddard, the center was established in 1959 as NASA’s first space flight complex. Goddard and its several facilities are critical in carrying out NASA’s missions of space exploration and scientific discovery.

    NASA Goddard Campus
    NASA/Goddard Campus

    NASA

     
  • richardmitnick 3:43 pm on July 29, 2014 Permalink | Reply
    Tags: , Space Weather,   

    From SPACE.com: ” Huge Solar Storm of 2012 Would Have Sparked Calamity on Earth” 

    space-dot-com logo

    SPACE.com

    July 29, 2014
    Elizabeth Howell

    If a huge solar eruption in 2012 had hit the Earth, the effects would have been so devastating that we’d still be recovering two years later, scientists working on several new studies conclude.

    A huge coronal mass ejection — a large cloud of hot plasma sent into space — burst forth from the sun on July 23, 2012. The CME went through Earth’s orbit, and had it happened only one week earlier, our planet would have been in the way and faced severe technological consequences.

    There would have been three waves of damage associated with the extreme solar storm. First, X-rays and ultraviolet radiation from the solar flare would have produced radio blackouts and GPS navigation errors. The second part would have seen satellites fried by energetic particles like electrons and protons, which arrived only minutes to hours later.

    Finally, magnetized plasma from the CME would have struck our planet within the next day. Power blackouts could have been devastating, making it difficult to even flush the toilet because most urban areas use electric water pumps.

    “I have come away from our recent studies more convinced than ever that Earth and its inhabitants were incredibly fortunate that the 2012 eruption happened when it did,” Daniel Baker at the University of Colorado, who led a study of the storm in Space Weather, said in a statement.

    spurts
    A huge solar storm in 2012 could have cause wide-spread devastation on Earth, if it had given the planet a direct blow.
    Credit: Solar Dynamics Observatory/NASA

    Disturbance in the solar force

    Researchers know about severity of the space weather thanks to NASA’s STEREO-A spacecraft, one of a twin NASA pair of satellites that is examining the sun. It found that the magnitude of the flare was similar to the Carrington event, an 1859 solar storm that set telegraph lines aflame as the Northern Lights were seen as far south as Cuba.

    stereo
    NASA/STEREO

    STEREO-A wasn’t hurt by the blast because it travelled safely outside the Earth’s magnetosphere, a zone above our planet that carries magnetic currents and can short out satellites. Also, the satellite was designed to withstand solar shocks — unlike some others.

    “Thanks to STEREO-A we know a lot of about the magnetic structure of the CME, the kind of shock waves and energetic particles it produced, and perhaps most importantly of all, the number of CMEs that preceded it,” Pete Riley of Predictive Science Inc., who published an unrelated paper in Space Weather, said in the same statement.

    Riley calculated that in the next 10 years, there is a 12 percent chance that a Carrington-class solar storm could happen. He used a parameter called Dst, “disturbance – storm time,” that looks at how much the magnetic field around Earth shakes when coronal mass ejections hit.

    Astronomers today estimate the Dst for Carrington was anywhere between negative 800 nanoTesla (nT) and negative 1,750 nT. By comparison, an ordinary storm that causes northern and southern lights only produces about negative 50 nT.

    In March 1989, the province of Quebec in Canada lost power due to an intense solar storm that was measured at negative 600 nT. The geomagnetic storm that narrow missed Earth in 2012 was twice as powerful, Riley said.

    ‘Perfect solar storm’

    The 2012 storm was so powerful that several coronal mass ejections erupted from the sun, creating a “superstorm” that made it many times more powerful than an ordinary one, an unrelated paper in Nature Communications said.

    The blast was actually a “double-CME” — two CMEs separated by only 10 to 15 minutes — that whizzed through an area of space that had already been cleaned by another CME just four days before.

    This meant the interplanetary medium in that region was not as thick as usual, the University of California, Berkeley’s Janet Luhmann and former postdoctoral researcher Ying Liu found.

    “It’s likely that the Carrington event was also associated with multiple eruptions, and this may turn out to be a key requirement for extreme events,” added Riley. “In fact, it seems that extreme events may require an ideal combination of a number of key features to produce the ‘perfect solar storm.”

    See the full article here.


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  • richardmitnick 9:35 am on March 7, 2014 Permalink | Reply
    Tags: , , , , NASA THEMIS, Space Weather   

    From NASA: “NASA’s THEMIS Discovers New Process that Protects Earth from Space Weather” 

    NASA

    NASA THEMIS
    THEMIS

    In the giant system that connects Earth to the sun, one key event happens over and over: solar material streams toward Earth and the giant magnetic bubble around Earth, the magnetosphere helps keep it at bay. The parameters, however, change: The particles streaming in could be from the constant solar wind, or perhaps from a giant cloud erupting off the sun called a coronal mass ejection [CME], . Sometimes the configuration is such that the magnetosphere blocks almost all the material, other times the connection is long and strong, allowing much material in. Understanding just what circumstances lead to what results is a key part of protecting our orbiting spacecraft from the effects of such space weather.

    themis graph
    NASA’s THEMIS mission observed how dense particles normally near Earth in a layer of the uppermost atmosphere called the plasmasphere can send a plume up through space to help protect against incoming solar particles during certain space weather events.
    Image Credit: NASA/Goddard Space Flight Center

    Now, for the first time, a study shows that in certain circumstances a pool of dense particles normally circling Earth, deep inside the magnetosphere, can extend a long arm out to meet and help block incoming solar material.

    “It’s like what you might do if a monster tried to break into your house. You’d stack furniture up against the front door, and that’s close to what the Earth is doing here,” said Brian Walsh, a space scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md. “The material that is usually much nearer Earth stacks up against the outer boundary of the magnetosphere, throttling the interaction there and stopping solar material from entering.”

    In the March 6, 2014, issue of Science Express, Walsh and his colleagues compared observations from the ground and in space during a solar storm on Jan. 17, 2013. This was a fairly moderate solar storm caused by a CME impacting Earth’s magnetosphere for several hours. As the CME encountered the boundary of the magnetosphere, its magnetic fields and those around Earth realigned in a process called magnetic reconnection, which allowed energy and solar material to cross the boundary into the magnetosphere. NASA’s three THEMIS [for Time History of Events and Macroscale Interactions during Substorms] spacecraft were in the right place at the right time, flying through the magnetosphere’s boundary approximately 45 minutes apart, and caught this interaction.

    flow
    A thin layer of cold, dense material called the plasmasphere surrounds Earth. Researchers have found that material in the plasmasphere can help prevent particles from the sun crossing into near Earth space.
    Image Credit: NASA

    Closer to Earth, scientists could also study the sphere of cold dense gas at the very top of our atmosphere. This region is called the plasmasphere and it’s made of what’s known as plasma, a gas made of charged particles. GPS signals travel through the plasmasphere and they travel at different speeds depending on how thick or thin the plasmasphere is along the journey. Tracking the GPS radio signals, therefore, can help researchers map out the properties of the plasmasphere.

    “A colleague who works with these kind of observations said I had to see some interesting data showing a plume from the ground,” said Walsh. “And I typed in the dates and saw that it was a date when THEMIS was in the right position. So, for the first time, we could make a comparison.”

    THEMIS showed that the tongue of this cold, dense plasmasphere material stretched all the way up to the magnetic reconnection point where the CME had made contact with the magnetopause. The three sets of THEMIS observations demonstrated that the plume had a dramatic impact on the characteristics of the magnetic reconnection region.

    “It wouldn’t work if the magnetic reconnection happened for only a few minutes,” said David Sibeck the project scientist for THEMIS at NASA Goddard. “But if it lasts long enough, the whole magnetosphere gets involved. This tongue of the plasmasphere surges out, adding another layer of protection, curbing the magnetic reconnection.”Â

    As scientists try to better understand the space weather system around Earth, they rely on multipoint observations such as this to connect what’s seen on the ground to what’s seen in space. In this case THEMIS data connected to GPS data, but such combinations are increasingly being used to watch how Earth is affected by its closest star. Eventually such observations could lead to improvements in space weather predictions, which would be as useful for spacecraft operators as terrestrial weather forecasts are for us here on Earth.

    For more information about NASA’s THEMIS mission, visit:

    http://www.nasa.gov/themis

    See the full article here.


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