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  • richardmitnick 12:00 pm on May 13, 2017 Permalink | Reply
    Tags: , , popsci.com, Solar research   

    From popsci.com: “How NASA is planning to touch the sun” 

    popsci-bloc

    Popular Science

    February 14, 2017 [Where has this been?]
    Ian Graber-Stiehl

    A look behind the scenes of NASA’s advanced solar probe

    1
    An explosion on the sun shoots fiery plasma out into space. NASA/Goddard/SDO

    Our sun might not seem as enigmatic as more exotic, distant stars, but it’s still a marvelously mysterious miasma of incandescent plasma. And it’s certainly worthy of our scientific attention: Curiosity aside, a violent solar event could disrupt satellites and cause $2 trillion in damages for the U.S. alone. Yet, despite living in its atmosphere, we don’t understand some of its defining phenomena. For sixty years, we haven’t understood why the surface is a cozy 5,500 Celsius, while the halo called the corona—several million kilometers away from the star’s surface and 12 orders of magnitude less dense—boasts a positively sizzling 1-2 million Celsius.

    To figure out why, NASA needs to fly a little closer to the sun—and touch it.

    We know that magnetic reconnection—when magnetic field lines moving in opposite directions intertwine and snap like rubber bands—propels nuclear weapon-like waves of energy away from surface. Meanwhile, magnetohydrodynamic waves—vibrating guitar string-like waves of magnetic force driven by the flow of plasma—transfer energy from the surface into corona. However, without more data, our understanding of phenomena like coronal heating and solar wind acceleration remain largely theoretical…but not for long.

    Launching in 2018, NASA’s Solar Probe Plus will travel nearly seven years, setting a new record for fastest moving object as it zips 37.6 million kilometers closer to the sun than any spacecraft that has ever studied our host star.

    2
    Artist’s impression of NASA’s Solar Probe Plus spacecraft on approach to the sun. Set to launch in 2018, Solar Probe Plus will orbit the sun 24 times, closing in with the help of seven Venus flybys. The spacecraft will carry 10 science instruments specifically designed to solve two key puzzles of solar physics: why the sun’s outer atmosphere is so much hotter than the sun’s visible surface, and what accelerates the solar wind that affects Earth and our solar system.
    Date 4 December 2008
    Source http://www.jhuapl.edu/newscenter/pressreleases/2014/140318.asp
    Author NASA/Johns Hopkins University Applied Physics Laboratory

    But what manner of sensory equipment does one bring to Dante’s Inferno?

    3
    From top left: the FIELDS experiment, ISIS, WISPR, SWEAP NASA/Johns Hopkins University Applied Physics Laboratory

    Spacecraft systems engineer Mary Kae Lockwood tells PopSci that the craft will rely on four main instruments. The Solar Wind Electrons Alphas and Protons systems, or SWEAP, will monitor charges created by colliding electrons, protons and helium ions to analyze solar wind—ninety times closer to the sun than previous attempts. Similarly, the ISIS (Integrated Science Investigation of the Sun) employs a state-of-the-art detection system to analyze energetic particles (think: cancer-causing, satellite-disabling particles).

    The FIELDS sensor, meanwhile, will analyze electric and magnetic fields, radio emissions, and shock waves—while gathering information on the high-speed dust particles sanding away at the craft using a technique discovered by accident. Lastly, the Wide-field Imager for Solar Probe, or WISPR telescope, will make 3D, cat-scan-like images of solar wind and the sun’s atmosphere.

    There’s just one problem. Between intense heat, solar radiation, high-energy particles, the fallout of solar storms, dust, and limited communication opportunities at closest approach, all that sensitive equipment is going to an environment that almost makes Juno’s new home look sympathetic by comparison.

    “One of the things we had to watch out for in the design,” according to Lockwood, was the electrical “charging” of the spacecraft by the solar wind. The probe has to be conductive “so that the instruments that are actually measuring the solar wind don’t have interference.”

    4
    The probe’s planned trajectory. NASA/Johns Hopkins University Applied Physics Laboratory

    To get close enough to worry about that, though, the probe’s has to “lose some energy” says Lockwood, performing several Venus flybys to shrink its orbit “[allowing] us to get . . . closer and closer to the sun.”

    However, that comes with “interesting design challenges, because you’re not only going into the sun” as heatshield mechanical engineer Beth Congdon tells PopSci. “You get hot on approach, and then come out and get cold,” over and over for 7 flybys and 24 orbits. “You actually need to have it cyclically survive hot and cold temperatures.” And high energy particles. And hypervelocity dust. For that, you need a heat shield “different from any other heat shield that has ever existed.”

    5
    NASA/Johns Hopkins University Applied Physics Laboratory

    The incandescent elephant in the room

    “A lot of heat shields you typically think about, like the shuttle . . . They have a few minutes maximum of that kind of heat.” But at the probe’s closest approach of 5.9 million kilometers, Congdon says, temperatures will reach up to 1,377 Celsius for a full day.

    But carbon can come to the rescue. “On Earth, carbon likes to oxidise and make barbeque,” chimes Congdon, “[but] in the vacuum of space, it’s a great material for high temperature applications. The probe’s shield is made of carbon foam, sandwiched between layers of carbon composite, with a reflective ceramic coating.

    What’s more, she says, most shields have the luxury of being attached to a vibration-dampening platform. This shield, on the other hand, had to be integrated in such a way that it could mitigate vibration without one “so that we could keep the whole system as low mass as possible.” The slim, trim, and ultralight build, however, makes it challenging to keep all the sensitive equipment hidden safely behind it.

    To that end, the craft is outfitted with solar limb sensors. These sensors would be the first thing to get illuminated if the spacecraft started drifting off-kilter, and would inform the autonomous guidance and control system that keeps all the instruments behind the thermal protection system, and which is even outfitted with a backup processor in case of any malfunctions.

    Meanwhile, the solar array, facing solar intensity 475 times greater than here on Earth—in an environment where “one degree of change, at closest approach, equals a 30 percent change in power”—will automatically retract behind the heat shield whenever it swings toward the sun. From there, it’ll be kept at a cool 160 Celsius by a network of water-filled titanium channels.

    So while the heatshield weathers a minefield of million-mile-per-hour winds and countless coronal mass ejections, the communication system scarcely able to relay information for 11 straight days, the array will be kept comfortable—all while powering an autonomous 1,345 lb scientist on the doorstep of our little cosmic neighborhood’s big, confounding catalyst.

    “Going to a place changes everything we think about a place. Just look at New Horizons and how it’s changed our thoughts, beliefs, and understanding of Pluto. We’re really excited to go and totally change our view of the sun,” says Congdon. Understanding the sun’s defining phenomena is a tantalizing goal. But first we have to contend with 143.3 million kilometers of space—and one of NASA’s most technically challenging builds, over half a century in the making.

    See the full article here .

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  • richardmitnick 1:03 pm on May 9, 2017 Permalink | Reply
    Tags: , , , , , RAISE (Rapid Acquisition Imaging Spectrograph Experiment), Solar research   

    From COSMOS: “A simple rocket for staring at the sun” 

    Cosmos Magazine bloc

    COSMOS

    09 May 2017
    Jana Howden

    1
    The RAISE rocket being prepared for take-off. Amir Caspi, Southwest Research Institute

    Capable of snapping 1,500 images in just five minutes, NASA’s newly launched rocket is raising the bar on studies of the sun. RAISE (Rapid Acquisition Imaging Spectrograph Experiment) is a type of sounding rocket, a relatively simple and cost-effective rocket that goes up 300 kilometres and spends 15–20 minutes making observations from above the atmosphere before returning to the ground.

    Although NASA runs several missions geared towards continuous study of the sun, this new sounding rocket, RAISE will allow researchers to study the fast processes and split-second changes occurring near the sun’s active regions.

    These active regions are areas of complex and intense magnetic activity that can cause solar flares, which spew energy and solar material into space.

    “With RAISE, we’ll read out an image every two-tenths of a second, so we can study very fast processes and changes on the sun,” explains Don Hassler, principal investigator for the RAISE mission.

    The data collected by RAISE can be used to create what’s called a spectrogram – a visual representation of the light emitted by the sun at different wavelengths. Looking at the intensity of light at these different wavelengths allows scientists to study the ways in which energy and solar material moves around the sun, and how this can evolve into solar eruptions.

    RAISE was launched on 5 May from a missile range in the US state of New Mexico, soaring to an altitude of around 296 kilometres before parachuting gently down to Earth, where the machine is to be recovered and reused.

    Read more at NASA.

    Related Links

    More about NASA’s sounding rocket program

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  • richardmitnick 4:30 pm on May 8, 2017 Permalink | Reply
    Tags: Berkeley, CME's, , , , Solar research, Space Sciences Laboratory at University of California   

    From Goddard: “Space Weather Model Simulates Solar Storms From Nowhere” 

    NASA Goddard Banner
    NASA Goddard Space Flight Center

    May 8, 2017
    Lina Tran
    kathalina.k.tran@nasa.gov
    NASA’s Goddard Space Flight Center, Greenbelt, Md.

    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.


    SSL UC Berkeley campus


    Space Science Labs UC Berkeley

    The scientists relied upon NASA missions STEREO and SOHO for this work, fine-tuning their model until the simulations matched the space-based observations.

    NASA/STEREO spacecraft


    ESA/NASA SOHO

    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.

    1
    Watch the evolution of a stealth CME in this simulation. Differential rotation creates a twisted mass of magnetic fields on the sun, which then pinches off and speeds out into space. The image of the sun is from NASA’s STEREO. Colored lines depict magnetic field lines, and the different colors indicate in which layers of the sun’s atmosphere they originate. The white lines become stressed and form a coil, eventually erupting from the sun. Credits: NASA’s Goddard Space Flight Center/ARMS/Joy Ng, producer

    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.

    Related

    New Space Weather Model Helps Simulate Magnetic Structure of Solar Storms
    NASA Scientists Demonstrate Technique to Improve Particle Warnings that Protect Astronauts

    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

     
  • richardmitnick 11:25 am on May 8, 2017 Permalink | Reply
    Tags: , , Solar research,   

    From AAS NOVA: ” Escape for the Slow Solar Wind” 

    AASNOVA

    American Astronomical Society

    8 May 2017
    Susanna Kohler

    1
    This Solar Dynamics Observatory extreme ultraviolet image of the Sun reveals a coronal hole — a region of open magnetic field — surrounded by regions of closed magnetic field. A new study examines how plasma might escape from regions of closed magnetic field on the Sun. [SDO; adapted from Higginson et al. 2017]

    NASA/SDO

    Plasma from the Sun known as the slow solar wind has been observed far away from where scientists thought it was produced. Now new simulations may have resolved the puzzle of where the slow solar wind comes from and how it escapes the Sun to travel through our solar system.

    An Origin Puzzle

    The Sun’s atmosphere, known as the corona, is divided into two types of regions based on the behavior of magnetic field lines. In closed-field regions, the magnetic field is firmly anchored in the photosphere at both ends of field lines, so traveling plasma is confined to coronal loops and must return to the Sun’s surface. In open-field regions, only one end of each magnetic field line is anchored in the photosphere, so plasma is able to stream from the Sun’s surface out into the solar system.

    This second type of region — known as a coronal hole — is thought to be the origin of fast-moving plasma measured in our solar system and known as the fast solar wind. But we also observe a slow solar wind: plasma that moves at speeds of less than 500 km/s.

    The slow solar wind presents a conundrum. Its observational properties strongly suggest it originates in the hot, closed corona rather than the cooler, open regions. But if the slow solar wind plasma originates in closed-field regions of the Sun’s atmosphere, then how does it escape from the Sun?

    Slow Wind from Closed Fields

    A team of scientists led by Aleida Higginson (University of Michigan) has now used high-resolution, three-dimensional magnetohydrodynamic simulations to show how the slow solar wind can be generated from plasma that starts out in closed-field parts of the Sun.

    Motions on the Sun’s surface near the boundary between open and closed-field regions — the boundary that marks the edges of coronal holes and extends outward as the heliospheric current sheet — are caused by supergranule-like convective flows. These motions drive magnetic reconnection that funnel plasma from the closed-field region onto enormous arcs that extend far away from the heliospheric current sheet, spanning tens of degrees in latitude and longitude.

    The simulations by Higginson and collaborators demonstrate that closed-field plasma from coronal-hole boundaries can be successfully channeled into the solar system. Due to the geometry and dynamics of the coronal holes, the plasma can travel far from the heliospheric current sheet, resulting in a slow solar wind of closed-field plasma consistent with our observations. These simulations therefore suggest a process that resolves the long-standing puzzle of the slow solar wind.

    Citation

    A. K. Higginson et al 2017 ApJL 840 L10. doi:10.3847/2041-8213/aa6d72

    Related Journal Articles:
    See the full article for further research with links.

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  • richardmitnick 8:06 am on May 5, 2017 Permalink | Reply
    Tags: , , , Solar research   

    From Eos: “Integrating Research of the Sun-Earth System” 

    AGU bloc

    AGU
    Eos news bloc

    Eos

    2 May 2017
    Vania K. Jordanova
    Joseph E. Borovsky
    Valentin T. Jordanov

    1
    A rendering of the sunset from space. Attendees at a recent symposium convened to chart new courses in research about the reaction of the Earth system to the Sun and the solar wind. Credit: iStock.com/RomoloTavani

    Understanding the complex interactions between the magnetic fields of the Sun and Earth remains an important challenge to space physics research. Processes that occur near the Sun at tens of thousands of kilometers from the Earth can generate geomagnetic storms that affect the entire magnetosphere, down to the upper atmosphere.

    Solar eruption 2012 by NASA’s Solar Dynamic Observatory SDO

    NASA/SDO

    These storms also threaten the ever more sophisticated technologies that we place into the space environment to sustain us, for example, GPS, the satellites we rely on to monitor our weather, and relays that guide our radio transmissions. Increasingly, we need to develop space weather models that can provide timely and accurate predictions so that we can safeguard our society and the infrastructure we depend on.

    Against this backdrop, the third International Symposium on Recent Observations and Simulations of the Sun-Earth System (ISROSES-III) convened in Bulgaria last year to discuss recent advances and chart future developments in space weather research. ISROSES-III built upon the legacy of other similar conferences held in Bulgaria in 2002, 2006, and 2011.

    The main purpose of ISROSES-III was to foster interdisciplinary research and collaboration by enhancing communications between the space and Earth sciences communities worldwide. About 100 participants from around the world convened at the symposium to cover a broad range of topics.

    These topics included the fundamental physics of how waves and shocks in magnetic fields create dangerous radiation by accelerating particles throughout space. One study at the meeting examined the origin of these particles as measured from geosynchronous orbit.

    Another study analyzed the types of magnetic disturbances that lead to geomagnetic storms. Others focused on the structure of Earth’s magnetospheric current systems, improving our understanding of them and how they map to the ionosphere. Yet another detailed an improved representation of magnetospheric electric potential to create more accurate simulations.

    The main emphasis of the discussions was on integrating observations, theory, and numerical modeling across different temporal and spatial scales of the coupled Sun-Earth system.

    The community also highlighted common misconceptions as well as the need to develop contemporary and innovative technologies in space exploration (Figure 1). In the research community, it is easier to denounce new concepts than express doubt in old, deeply held misconceptions. In contrast, in the market economy, old concepts or misconceptions are constantly abandoned in search for something new. Symposium attendees discussed how the market economy has created new technologies that they should explore and that the research community needs to adopt the flexible mindset of corporations.

    1
    Fig. 1. Radiation measurement instrumentation versus consumer technology. (left) In the research community it is easier to denounce new concepts than express doubt in believed old misconceptions. (right) In the market economy, old concepts or misconceptions are constantly abandoned in search for something new. Attendees at a recent symposium on the Sun-Earth system stressed that new ideas brought into focus by the market economy shouldn’t be dismissed and that the research community should adopt the flexible mindset of corporations. Credit: Valentin T. Jordanov

    A special issue of the Journal of Atmospheric and Solar-Terrestrial Physics is currently being organized to publish papers related to topics discussed at ISROSES-III. Further information about the symposium is available on its official website [link is above].

    The main sponsors of the symposium were the Los Alamos National Laboratory Center for Space and Earth Science, the National Science Foundation, and the Scientific Committee on Solar-Terrestrial Physics’s Variability of the Sun and Its Terrestrial Impact (VarSITI) program. ISROSES-III also received collaboration and support locally from the University of Sofia, Bulgaria.

    —Vania K. Jordanova (email: vania@lanl.gov), Los Alamos National Laboratory, Los Alamos, N.M.; Joseph E. Borovsky, Space Science Institute, Boulder, Colo.; and Valentin T. Jordanov, Yantel LLC, Santa Fe, N.M.
    Citation: Jordanova, V. K., J. E. Borovsky, and V. T. Jordanov (2017), Integrating research of the Sun-Earth system, Eos, 98, https://doi.org/10.1029/2017EO072499. Published on 02 May 2017.

    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 12:43 pm on May 3, 2017 Permalink | Reply
    Tags: , Solar research, SPACE SCIENCE LAB,   

    From SSL at UC Berkeley: “Solar Array Cooling System Coming Together on Solar Probe Plus” 

    UC Berkeley

    UC Berkeley

    Space Science Labs UC Berkeley

    Space Science Lab

    2
    The Solar Array Cooling System on Solar Probe Plus has one critical job – to protect the NASA spacecraft’s solar arrays from incineration as it moves through the blazing atmosphere of the sun.

    Several key elements of that system are now on board the spacecraft, installed last week during ongoing integration and test operations at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland. On April 5, engineers carefully attached the deck that holds the solar array cooling system components, solar array cooling system radiators and the truss structure assembly, or TSA. The TSA will support the spacecraft’s signature 8-foot-wide, 4.5-inch-thick carbon-carbon foam heat shield, as well components from the FIELDS experiment and Solar Wind Electrons, Alphas and Protons (SWEAP) suite that will make direct measurements of the charged particles and electrical fields in the solar environment.

    Solar Probe Plus is on track for launch during a 20-day window that opens July 31, 2018. Integration and testing will continue at APL through November; after that, the spacecraft will be moved to NASA Goddard Space Flight Center in Greenbelt, Maryland, for four months of final space-environmental testing, it is then shipped to Kennedy Space Center/Cape Canaveral Air Force Station, Florida, in March 2018 for final launch preparations. APL designed, is building, and will operate Solar Probe Plus for NASA.

    3
    Mission integration and test team members secure the deck holding the structure assembly and several other critical thermal-protection components atop NASA’s Solar Probe Plus spacecraft body on April 5, 2017, in the cleanroom at the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland. NASA/Johns Hopkins University Applied Physics Laboratory

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    Founded in the wake of the gold rush by leaders of the newly established 31st state, the University of California’s flagship campus at Berkeley has become one of the preeminent universities in the world. Its early guiding lights, charged with providing education (both “practical” and “classical”) for the state’s people, gradually established a distinguished faculty (with 22 Nobel laureates to date), a stellar research library, and more than 350 academic programs.

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  • richardmitnick 9:51 am on April 27, 2017 Permalink | Reply
    Tags: Joint Japan Aerospace Exploration Agency NASA Hinode satellite, , Scientists Propose Mechanism to Describe Solar Eruptions of All Sizes, , , Solar research   

    From Goddard: “Scientists Propose Mechanism to Describe Solar Eruptions of All Sizes” 

    NASA Goddard Banner
    NASA Goddard Space Flight Center

    April 26, 2017
    Lina Tran
    kathalina.k.tran@nasa.gov
    NASA’s Goddard Space Flight Center, Greenbelt, Md.

    1
    A long filament erupted on the sun on Aug. 31, 2012, shown here in imagery captured by NASA’s Solar Dynamics Observatory. Credit: NASA’s Goddard Space Flight Center/SDO
    From long, tapered jets to massive explosions of solar material and energy, eruptions on the sun come in many shapes and sizes. Since they erupt at such vastly different scales, jets and the massive clouds — called coronal mass ejections, or CMEs — were previously thought to be driven by different processes.

    Scientists from Durham University in the United Kingdom and NASA now propose that a universal mechanism can explain the whole spectrum of solar eruptions. They used 3-D computer simulations to demonstrate that a variety of eruptions can theoretically be thought of as the same kind of event, only in different sizes and manifested in different ways. Their work is summarized in a paper published in Nature on April 26, 2017.


    Follow the evolution of a jet eruption in this video, which uses a 3-D computer simulation of the breakout model to demonstrate how a filament forms, gains energy and erupts from the sun.
    Credits: NASA’s Goddard Space Flight Center/ARMS/Genna Duberstein, producer

    The study was motivated by high-resolution observations of filaments from NASA’s Solar Dynamics Observatory, or SDO, and the joint Japan Aerospace Exploration Agency/NASA Hinode satellite.

    NASA/SDO

    JAXA/HINODE spacecraft

    Filaments are dark, serpentine structures that are suspended above the sun’s surface and consist of dense, cold solar material. The onset of CME eruptions had long been known to be associated with filaments, but improved observations have recently shown that jets have similar filament-like structures before eruption too. So the scientists set out to see if they could get their computer simulations to link filaments to jet eruptions as well.

    “In CMEs, filaments are large, and when they become unstable, they erupt,” said Peter Wyper, a solar physicist at Durham University and the lead author of the study. “Recent observations have shown the same thing may be happening in smaller events such as coronal jets. Our theoretical model shows the jet can essentially be described as a mini-CME.”

    Solar scientists can use computer models like this to help round out their understanding of the observations they see through space telescopes. The models can be used to test different theories, essentially creating simulated experiments that cannot, of course, be performed on an actual star in real life.

    The scientists call their proposed mechanism for how these filaments lead to eruptions the breakout model, for the way the stressed filament pushes relentlessly at — and ultimately breaks through — its magnetic restraints into space. They previously used this model to describe CMEs; in this study, the scientists adapted the model to smaller events and were able to reproduce jets in the computer simulations that match the SDO and Hinode observations. Such simulations provide additional confirmation to support the observations that first suggested coronal jets and CMEs are caused in the same way.

    “The breakout model unifies our picture of what’s going on at the sun,” said Richard DeVore, a co-author of the study and solar physicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “Within a unified context, we can advance understanding of how these eruptions are started, how to predict them and how to better understand their consequences.”

    The key for understanding a solar eruption, according to Wyper, is recognizing how the filament system loses equilibrium, which triggers eruption. In the breakout model, the culprit is magnetic reconnection — a process in which magnetic field lines come together and explosively realign into a new configuration.

    NASA Magnetic reconnection, Credit: M. Aschwanden et al. (LMSAL), TRACE, NASA

    In stable conditions, loops of magnetic field lines hold the filament down and suppress eruption. But the filament naturally wants to expand outward, which stresses its magnetic surroundings over time and eventually initiates magnetic reconnection. The process explosively releases the energy stored in the filament, which breaks out from the sun’s surface and is ejected into space.

    Exactly which kind of eruption occurs depends on the initial strength and configuration of the magnetic field lines containing the filament. In a CME, field lines form closed loops completely surrounding the filament, so a bubble-shaped cloud ultimately bursts from the sun. In jets, nearby fields lines stream freely from the surface into interplanetary space, so solar material from the filament flows out along those reconnected lines away from the sun.

    “Now we have the possibility to explain a continuum of eruptions through the same process,” Wyper said. “With this mechanism, we can understand the similarities between small jets and massive CMEs, and infer eruptions anywhere in between.”

    Confirming this theoretical mechanism will require high-resolution observations of the magnetic field and plasma flows in the solar atmosphere, especially around the sun’s poles where many jets originate — and that’s data that currently are not available. For now, scientists look to upcoming missions such as NASA’s Solar Probe Plus and the joint ESA (European Space Agency)/NASA Solar Orbiter, which will acquire novel measurements of the sun’s atmosphere and magnetic fields emanating from solar eruptions.

    NASA/SPP Solar Probe Plus

    NASA/ESA Solar Orbiter

    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

     
  • richardmitnick 3:40 pm on April 10, 2017 Permalink | Reply
    Tags: , , , , , Solar research   

    From NJIT: Putting Students Closer to Explosive Solar Events 

    NJIT Bloc

    New Jersey Institute of Technology

    1

    April 6, 2017

    NJIT has a long-established reputation as a leader in researching phenomena originating on the star closest to Earth — the Sun. NJIT’s optical telescope at Big Bear Solar Observatory and radio telescope array at Owens Valley, both in California, have greatly expanded our understanding of solar events that periodically impact our home planet, events such as solar flares and coronal mass ejections (CMEs) that can disrupt terrestrial communications and power infrastructure in addition to other effects.

    NJIT Big Bear Solar Observatory, located on the north side of Big Bear Lake in the San Bernardino Mountains of southwestern San Bernardino County, California, approximately 120 kilometers east of downtown Los Angeles

    Ten antennas of NJIT’s 13-antenna Expanded Owens Valley Solar Array (EOVSA)

    Under the auspices of the university’s Center for Solar-Terrestrial Research (CSTR), NJIT investigators are collaborating with colleagues in the U.S. and other countries to gain even more critical knowledge of solar physics. It’s knowledge essential not only for better basic understanding of the Sun but also to improve prediction of the solar explosions that threaten our technologies and to devise better countermeasures.

    What’s more, NJIT researchers are committed to fully engaging students in the search for this knowledge — researchers like Assistant Professor of Physics Bin Chen, who joined the NJIT faculty in 2016. Chen was recently awarded a five-year CAREER grant totaling more than $700,000 by the National Science Foundation (NSF). The NSF’s Faculty Early Career Development (CAREER) program offers the foundation’s most prestigious awards in support of younger faculty who, in building their academic careers, have demonstrated outstanding potential as both educators and researchers.

    Chen completed his Ph.D. at the University of Virginia in 2013 with a focus on solar radio astronomy. His Ph.D. advisor introduced him to fellow solar astronomer, and now NJIT colleague, Distinguished Professor of Physics Dale Gary. Through his acquaintance with Gary, and the opportunity to collaborate on a research project using observational data from NJIT’s Owens Valley Solar Array, Chen learned about the university’s leading-edge efforts in solar radio physics. But before he joined NJIT after receiving his doctorate, Chen added to his research experience through a postdoctoral fellowship under NASA’s Living With a Star program and as an astrophysicist at the Harvard Smithsonian Center for Astrophysics, where he worked on space missions dedicated primarily to solar science.

    Shocking Insights

    Although not yet fellow faculty members at NJIT, Chen and Gary did collaborate with researchers from the National Radio Astronomy Observatory, the University of California, the University of Applied Sciences and Arts Northwestern Switzerland and the University of Minnesota on an article for the journal Science published in 2015, Particle Acceleration by a Solar Flare Termination Shock. The article presented radio imaging data that provides new insights into how a phenomenon known as termination shock associated with solar flares, the most powerful explosions in the solar system, helps to accelerate energetic electrons in the flares to relativistic speeds — propelling these particles into space at nearly the speed of light.

    Chen is now continuing this investigation at NJIT. “There is a lot we don’t know about the ‘inside’ of these solar explosions and how they release so much energy so quickly and so catastrophically,” he says. “For example, how is the energy stored and suddenly released, often in a matter of seconds?

    “The relativistic particle acceleration that we are also studying as part of this research is a process taking place across the universe and is a phenomenon associated with, for example, the massive star explosions known as supernovae. The Sun is a good place to research this phenomenon because its nearness in astronomical terms allows us to acquire a volume of high-resolution data impossible to obtain from observing vastly more distant stars.”

    For his research, Chen is drawing on streams of radio data from a number of sources. In addition to NJIT’s radio observatory at Owens Valley, these include the Karl G. Jansky Very Large Array in New Mexico operated by the National Radio Astronomy Observatory and the Atacama Large Millimeter/Submillimeter Array in Chile.

    NRAO/VLA, on the Plains of San Agustin fifty miles west of Socorro, NM, USA

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    Recent upgrades at Owens Valley put it at the forefront of this research as a “new-generation” radio telescope. Another very important advantage afforded by Owens Valley, as Chen emphasizes, is that it is a facility dedicated full-time to solar research.

    Chen is one of the few researchers seeking new knowledge of the Sun by taking advantage of an observing technique called dynamic spectroscopy imaging. This technique allows capturing an image of the Sun every 50 milliseconds at more than a thousand frequencies, and at two different polarizations. This adds up to 40,000 images per second and terabytes of raw data in a day that can be converted into 3D images with resolution far greater than previously obtainable. “This gives us the potential to learn so much more about what is going on in the heart of solar explosions,” Chen says.

    Beyond greater understanding of the fundamental physics involved, Chen adds that his research is very much supportive of the goals of the U.S. National Space Weather Strategy and Action Plan, which reflects critical awareness of how space weather generated by solar phenomena impacts many aspects of terrestrial life and infrastructure. He says, “Solar flares and CMEs are the main drivers of space weather. Better understanding of these drivers is essential for better prediction of such events and the implementation of protective measures.”

    Bringing the Sun to Campus

    In Chen’s estimation, NJIT is uniquely experienced in building, operating and maintaining facilities dedicated to radio observation of the Sun. Potentially, for students, this presents exceptional opportunities to learn at the frontier of the many disciplines relevant to investigating the Sun in the radio spectrum — including hands-on familiarity with the equipment involved. While a limited number of students do have a chance to work at Owens Valley, as well as at Big Bear, distance and lack of appropriate accommodations prevent many more from participating in solar research on site. That’s why Chen also plans to apply a portion of his CAREER funding to creating a Solar Radio Laboratory on campus in Newark.

    “The idea behind the Solar Radio Laboratory is to have a facility on campus with the same state-of-the-art technology found at Owens Valley, just without the antennas,” Chen explains. “We’ll have all the electronics, the radio technology, the data-science capability for processing data streaming from California. This will give students the same hands-on opportunities for working and experimenting with the instrumentation that NJIT has at Owens Valley, instrumentation that is really unique in the United States. Another goal is to use this as a test bed for future improvements at Owens Valley, and to engage students in developing those improvements.”

    For Chen, a complementary educational goal is to also advance the Hale COLLAborative Graduate Education (COLLAGE) program in solar physics, which commemorates the name of the pioneering American solar astronomer George Ellery Hale. There are very few graduate programs in this field in the U.S. and the necessary faculty and physical resources are widely distributed across educational institutions as well as geography. To address this situation, Philip Goode, NJIT distinguished research professor of physics and former CSTR director, proposed that NJIT join with the University of Colorado-Boulder and several other institutions that had solar physics programs in what is now known as the COLLAGE program.

    “COLLAGE gives more students in different parts of the country access to the instruction and resources that allow them to complete master’s and Ph.D. degrees in solar physics,” Chen says. “I am already working with some 20 students, and that’s actually quite a large number for our field. But not only are we increasing opportunities to study solar physics at the graduate level, we’re learning more about coordinating resources among schools and teaching effectively online, which will benefit students who want to study many different complex subjects.”

    See the full article here .

    Please help promote STEM in your local schools.

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    NJIT campus

    Welcome to the New Jersey Institute of Technology. We’re proud of our 130 years of history, but that’s only the beginning of our story – we’ve doubled the size of our campus in the last decade, pouring millions into major new research facilities to give our students the edge they need in today’s demanding high-tech marketplace.

    NJIT offers 125 undergraduate and graduate degree programs in six specialized schools instructed by expert faculty, 98 percent of whom hold the highest degree in their field.

    Our academic programs are fully accredited by the appropriate accrediting boards, commissions and associations such as Middle States, ABET, and NAAB.

     
  • richardmitnick 1:36 pm on March 30, 2017 Permalink | Reply
    Tags: , , , , Draper, Solar research   

    From CfA: “Next Stop: A Trip Inside the Sun’s Atmosphere” 

    Harvard Smithsonian Center for Astrophysics


    Center For Astrophysics

    March 29, 2017
    Megan Watzke
    Harvard-Smithsonian Center for Astrophysics
    +1 617-496-7998
    mwatzke@cfa.harvard.edu

    Peter Edmonds
    Harvard-Smithsonian Center for Astrophysics
    +1 617-571-7279
    pedmonds@cfa.harvard.edu

    Dan Dent
    Draper Laboratory
    ddent@draper.com
    +1 617-258-2464

    1
    NASA’s Solar Probe Plus will enter the sun’s corona to understand space weather using a Faraday cup developed by the Smithsonian Astrophysical Observatory and Draper.
    NASA/Johns Hopkins University Applied Physics Laboratory

    Every so often the sun emits an explosive burst of charged particles that makes its way to Earth and often wreaks havoc on power grids, aircraft and satellite systems. When clouds of high-speed charged particles come racing off the sun, they can bathe spacecraft, astronauts and planetary surfaces in damaging radiation. Understanding why the sun occasionally emits these high-energy particles can help scientists predict space weather. Knowing when solar energetic particles may hit Earth can help people on the planet take precautions.

    Now, Draper and the Smithsonian Astrophysical Observatory (SAO) are addressing these challenges, and hoping to untangle these unsolved science mysteries, by developing sophisticated sensors for a new NASA mission. Launching in 2018, NASA’s Solar Probe Plus spacecraft, which is being designed and built by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will make 24 solar flybys over nearly seven years, setting a new record for the fastest moving man-made object as it zips 37.6 million kilometers closer to the sun than any spacecraft that has ever studied this star, and be exposed to temperatures exceeding 2500 degrees Fahrenheit.

    NASA’s Solar Probe Plus—the first mission that will fly into the sun’s upper atmosphere and “touch” the sun—will collect data on the mechanisms that heat the corona and accelerate the solar wind, a constant flow of charged particles from the sun. These are two processes with fundamental roles in the complex interconnected system linking the sun and near-Earth space—a system that can drive changes in our space weather and impact our satellites.

    To capture the velocity and direction of the positively-charged particles, Solar Probe Plus will be equipped with a Faraday cup, built by the Smithsonian Astrophysical Observatory, with technical support from Draper, and operated by SAO and the University of Michigan in Ann Arbor. The Faraday cup, which is capable of measuring the full force of supersonic solar particles and radiation, is one of only two instruments riding outside the protective sunshield of NASA’s Solar Probe Plus. The challenge will be to capture the data while operating at extreme temperatures on the fastest moving manmade spacecraft ever created—it will achieve a velocity of close to 200 km/sec—and do it with accuracy.

    For years, astronomers have studied the sun, but never from inside the sun’s atmosphere, according to Seamus Tuohy, Director of the Space Systems Program Office at Draper. “Such a mission would require a spacecraft and instrumentation capable of withstanding extremes of radiation, high velocity travel and the harsh solar condition—and that is the kind of program deeply familiar to Draper and the Smithsonian Astrophysical Observatory.”

    The investigation will specifically track the most abundant particles in the solar atmosphere and wind—electrons, protons and helium ions–“in addition to answering fundamental science questions, the intent is to better understand the risks space weather poses to the modern communication, aviation and energy systems we all rely on,” said Justin C. Kasper, principal investigator at the Smithsonian Astrophysical Observatory and University of Michigan Professor in Space Science. “Many of the systems we in the modern world rely on—our telecommunications, GPS, satellites and power grids—could be disrupted for an extended period of time if a large solar storm were to happen today. Solar Probe Plus will help us predict and manage the impact of space weather on society.”

    Draper

    At Draper, we believe exciting things happen when new capabilities are imagined and created. Whether formulating a concept and developing each component to achieve a field-ready prototype or combining existing technologies in new ways, Draper engineers apply multidisciplinary approaches that deliver new capabilities to customers. As a not-for-profit research and development company, Draper focuses on the design, development and deployment of advanced technological solutions for the world¹s most challenging and important problems. We provide engineering solutions directly to government, industry and academia; work on teams as prime contractor or subcontractor; and participate as a collaborator in consortia. We provide unbiased assessments of technology or systems designed or recommended by other organizations—custom designed, as well as commercial-off-the-shelf.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    The Center for Astrophysics combines the resources and research facilities of the Harvard College Observatory and the Smithsonian Astrophysical Observatory under a single director to pursue studies of those basic physical processes that determine the nature and evolution of the universe. The Smithsonian Astrophysical Observatory (SAO) is a bureau of the Smithsonian Institution, founded in 1890. The Harvard College Observatory (HCO), founded in 1839, is a research institution of the Faculty of Arts and Sciences, Harvard University, and provides facilities and substantial other support for teaching activities of the Department of Astronomy.

     
  • richardmitnick 9:30 am on March 29, 2017 Permalink | Reply
    Tags: , , , , ESA Solar Orbiter, , Solar research   

    From ICL: “Imperial instrument ready to study the Sun” 

    Imperial College London
    Imperial College London

    29 March 2017
    Hayley Dunning
    Thomas Angus [Photographer]

    1
    Artist’s impression of the Solar Orbiter. Credit: ESA/AOES

    Imperial’s contribution to the Solar Orbiter mission, which will go closer to the Sun than anything so far, is ready to fly after extensive testing.

    Solar Orbiter is a European Space Agency mission carrying ten instruments to measure many different properties of the Sun and interplanetary space.

    Aboard the spacecraft, launching in early 2019, will be a magnetometer instrument built by a team from the Department of Physics at Imperial.

    The magnetometer will measure the Sun’s magnetic field in interplanetary space, carried by the solar wind. The solar wind is a stream of charged particles coming off the Sun that fills the Solar System, which the Sun’s magnetic field plays an important role in creating.

    Principal Investigator Professor Tim Horbury from the Department of Physics at Imperial said: “We live inside a bubble blown by the Sun in interstellar space. The Earth also has its own magnetic field, which creates a cavity in the solar bubble.

    2
    Professor Tim Horbury describes Solar Orbiter’s journey

    “The interaction between the solar wind and Earth’s magnetic field gives us the aurora – the Northern and Southern Lights – but when the solar wind is strong it can also cause problems for our technology, from power grids to satellites.”

    The Sun’s magnetic field is thought to be generated in a similar way to the Earth’s as it rotates, but it is much more dynamic. Every 11 years the polarity reverses, and this pattern is tied to the pattern of sunspots that appear on the Sun’s surface. Sunspots are associated extreme events called solar flares and ejections of the solar material that cause serious problems if they reach Earth.

    By orbiting the Sun and approaching it at a distance of only 50 million kilometres – inside the orbit of Mercury, the closest planet to the Sun – the Imperial team’s magnetometer will be able to get unprecedented information about how the Sun generates its magnetic field and how this plays a role in the solar wind and more extreme events.

    Sensitive subject

    The instrument is made up of two sensors hosted within metal domes; a black box containing electronics, a computer processor and a power supply; and cables to provide power and communications to the sensors.

    3
    Helen O’Brien describes the working of the sensors

    The magnetometer has to be extremely sensitive to detect the magnetic field from the Sun that will reach the spacecraft. Lead engineer Helen O’Brien from the Department of Physics said: “Our instrument is so sensitive, it could measure the magnetic field of an MRI machine from the other side of London.

    “This means, however, that we have to work hard to isolate it from the other instruments on the spacecraft. Metal objects and electrical circuits create small magnetic fields, so we have really strict requirements on the rest of the project – right down to the screws and the paint.”

    The magnetometer also has to survive some extreme conditions, including the intense vibration from the take-off, which will use a NASA Atlas V rocket. An earlier model of the instrument, which was put through rigorous tests designed to exceed the expected conditions, crumbled under the strain.

    4

    O’Brien said: “We mounted the sensors on a ceramic material that barely expands or contracts with temperature changes, so that their relative position to each other is kept stable during the extreme temperature swings the spacecraft will experience. However, this material is quite brittle, and it fell apart in the vibration test.”

    Thickening the material helped to solve the problem, and as a result of rigorous testing many tweaks and improvements have been made to the design. But now, the device is finished, and it is waiting in a clean room at Imperial before it gets mounted onto the spacecraft.

    In the meantime, the team are building a ‘flight spare’ – an identical device just in case something happens to the original before launch. When the instrument is mounted on the spacecraft, the team will be giving extremely precise instructions – down to the material the screwdriver is made out of, and making sure no tiny shavings of metal are left behind, which could disturb the measurements.

    Once all the instruments are mounted, the whole spacecraft will go through another barrage of tests, before being shipped to Cape Canaveral for launch in February 2019. It will then spend two years getting to the Sun, and another eight collecting data. Eventually, its solar panels will degrade and stop producing power but it will drift around the Sun forever.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Imperial College London

    Imperial College London is a science-based university with an international reputation for excellence in teaching and research. Consistently rated amongst the world’s best universities, Imperial is committed to developing the next generation of researchers, scientists and academics through collaboration across disciplines. Located in the heart of London, Imperial is a multidisciplinary space for education, research, translation and commercialisation, harnessing science and innovation to tackle global challenges.

     
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