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  • richardmitnick 10:43 am on February 20, 2019 Permalink | Reply
    Tags: "Solar Tadpole-Like Jets Seen With NASA’S IRIS Add New Clue to Age-Old Mystery", , , , , , NASA IRIS, ,   

    From NASA Goddard Space Flight Center: “Solar Tadpole-Like Jets Seen With NASA’S IRIS Add New Clue to Age-Old Mystery” 

    NASA Goddard Banner
    From NASA Goddard Space Flight Center

    Feb. 19, 2019
    Mara Johnson-Groh
    mara.johnson-groh@nasa.gov
    NASA’s Goddard Space Flight Center, Greenbelt, Md.

    NASA IRIS spacecraft

    Scientists have discovered tadpole-shaped jets coming out of regions with intense magnetic fields on the Sun. Unlike those living on Earth, these “tadpoles” — formally called pseudo-shocks — are made entirely of plasma, the electrically conducting material made of charged particles that account for an estimated 99 percent of the observable universe. The discovery adds a new clue to one of the longest-standing mysteries in astrophysics.

    1
    Anmated images from IRIS show the tadpole-shaped jets containing pseudo-shocks streaking out from the Sun.
    Credits: Abhishek Srivastava IIT (BHU)/Joy Ng, NASA’s Goddard Space Flight Center

    For 150 years scientists have been trying to figure out why the wispy upper atmosphere of the Sun — the corona — is over 200 times hotter than the solar surface. This region, which extends millions of miles, somehow becomes superheated and continually releases highly charged particles, which race across the solar system at supersonic speeds.

    When those particles encounter Earth, they have the potential to harm satellites and astronauts, disrupt telecommunications, and even interfere with power grids during particularly strong events. Understanding how the corona gets so hot can ultimately help us understand the fundamental physics behind what drives these disruptions.

    In recent years, scientists have largely debated two possible explanations for coronal heating: nanoflares and electromagnetic waves. The nanoflare theory proposes bomb-like explosions, which release energy into the solar atmosphere. Siblings to the larger solar flares, they are expected to occur when magnetic field lines explosively reconnect, releasing a surge of hot, charged particles. An alternative theory suggests a type of electromagnetic wave called Alfvén waves might push charged particles into the atmosphere like an ocean wave pushing a surfer. Scientists now think the corona may be heated by a combination of phenomenon like these, instead of a single one alone.

    The new discovery of pseudo-shocks adds another player to that debate. Particularly, it may contribute heat to the corona during specific times, namely when the Sun is active, such as during solar maximums — the most active part of the Sun’s 11-year cycle marked by an increase in sunspots, solar flares and coronal mass ejections.

    The discovery of the solar tadpoles was somewhat fortuitous. When recently analyzing data from NASA’s Interface Region Imaging Spectrograph, or IRIS, scientists noticed unique elongated jets emerging from sunspots ­— cool, magnetically-active regions on the Sun’s surface — and rising 3,000 miles up into the inner corona. The jets, with bulky heads and rarefied tails, looked to the scientists like tadpoles swimming up through the Sun’s layers.

    “We were looking for waves and plasma ejecta, but instead, we noticed these dynamical pseudo-shocks, like disconnected plasma jets, that are not like real shocks but highly energetic to fulfill Sun’s radiative losses,” said Abhishek Srivastava, scientist at the Indian Institute of Technology (BHU) in Varanasi, India, and lead author on the new paper in Nature Astronomy.

    Using computer simulations matching the events, they determined these pseudo-shocks could carry enough energy and plasma to heat the inner corona.

    2
    Animated computer simulation shows how the pseudo-shock is ejected and becomes disconnected from the plasma below (green). Credits: Abhishek Srivastava IIT (BHU)/Joy Ng, NASA’s Goddard Space Flight Center

    The scientists believe the pseudo-shocks are ejected by magnetic reconnection — an explosive tangling of magnetic field lines, which often occurs in and around sunspots. The pseudo-shocks have only been observed around the rims of sunspots so far, but scientists expect they’ll be found in other highly magnetized regions as well.

    3
    The tadpole-shaped pseudo-shocks, shown in dashed white box, are ejected from highly magnetized regions on the solar surface. Credits: Abhishek Srivastava IIT (BHU)/Joy Ng, NASA’s Goddard Space Flight Center

    Over the past five years, IRIS has kept an eye on the Sun in its 10,000-plus orbits around Earth. It’s one of several in NASA’s Sun-staring fleet that have continually observed the Sun over the past two decades. Together, they are working to resolve the debate over coronal heating and solve other mysteries the Sun keeps.

    “From the beginning, the IRIS science investigation has focused on combining high-resolution observations of the solar atmosphere with numerical simulations that capture essential physical processes,” said Bart De Pontieu research scientist at Lockheed Martin Solar & Astrophysics Laboratory in Palo Alto, California. “This paper is a nice illustration of how such a coordinated approach can lead to new physical insights into what drives the dynamics of the solar atmosphere.”

    The newest member in NASA’s heliophysics fleet, Parker Solar Probe, may be able to provide some additional clues to the coronal heating mystery.

    NASA Parker Solar Probe Plus named to honor Pioneering Physicist Eugene Parker

    Launched in 2018, the spacecraft flies through the solar corona to trace how energy and heat move through the region and to explore what accelerates the solar wind as well as solar energetic particles. Looking at phenomena far above the region where pseudo-shocks are found, Parker Solar Probe’s investigation hopes to shed light on other heating mechanisms, like nanoflares and electromagnetic waves. This work will complement the research conducted with IRIS.

    “This new heating mechanism could be compared to the investigations that Parker Solar Probe will be doing,” said Aleida Higginson, deputy project scientist for Parker Solar Probe at Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland. “Together they could provide a comprehensive picture of coronal heating.”

    Related Links:

    Learn more about NASA’s IRIS Mission
    NASA’s Parker Solar Probe and the Curious Case of the Hot Corona
    Learn more about NASA’s Parker Solar Probe

    See the full article here.


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    Please help promote STEM in your local schools.

    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

     
  • richardmitnick 9:06 am on June 23, 2017 Permalink | Reply
    Tags: , NASA IRIS, Scientists Uncover Origins of the Sun’s Swirling Spicules, , Swedish 1-meter Solar Telescope in La Palma Spain   

    From Goddard: “Scientists Uncover Origins of the Sun’s Swirling Spicules” 

    NASA Goddard Banner
    NASA Goddard Space Flight Center

    June 22, 2017
    Lina Tran
    kathalina.k.tran@nasa.gov
    NASA’s Goddard Space Flight Center, Greenbelt, Md.

    1
    No image caption or credit.

    At any given moment, as many as 10 million wild jets of solar material burst from the sun’s surface. They erupt as fast as 60 miles per second, and can reach lengths of 6,000 miles before collapsing. These are spicules, and despite their grass-like abundance, scientists didn’t understand how they form. Now, for the first time, a computer simulation — so detailed it took a full year to run — shows how spicules form, helping scientists understand how spicules can break free of the sun’s surface and surge upward so quickly.

    This work relied upon high-cadence observations from NASA’s Interface Region Imaging Spectrograph, or IRIS, and the Swedish 1-meter Solar Telescope in La Palma, in the Canary Islands. Together, the spacecraft and telescope peer into the lower layers of the sun’s atmosphere, known as the interface region, where spicules form. The results of this NASA-funded study were published in Science on June 22, 2017 — a special time of the year for the IRIS mission, which celebrates its fourth anniversary in space on June 26.

    NASA IRIS spacecraft

    2
    Swedish 1-meter Solar Telescope in La Palma, in the Canary Islands, Spain


    Watch the video to learn how scientists used a combination of computer simulations and observations to determine how spicules form.
    Credits: NASA’s Goddard Space Flight Center/Joy Ng, producer

    “Numerical models and observations go hand in hand in our research,” said Bart De Pontieu, an author of the study and IRIS science lead at Lockheed Martin Solar and Astrophysics Laboratory, in Palo Alto, California. “We compare observations and models to figure out how well our models are performing, and to improve the models when we see major discrepancies.”

    Observing spicules has been a thorny problem for scientists who want to understand how solar material and energy move through and away from the sun. Spicules are transient, forming and collapsing over the course of just five to 10 minutes. These tenuous structures are also difficult to study from Earth, where the atmosphere often blurs our telescopes’ vision.

    A team of scientists has been working on this particular model for nearly a decade, trying again and again to create a version that would create spicules. Earlier versions of the model treated the interface region, the lower solar atmosphere, as a hot gas of electrically charged particles — or more technically, a fully ionized plasma. But the scientists knew something was missing because they never saw spicules in the simulations.

    The key, the scientists realized, was neutral particles. They were inspired by Earth’s own ionosphere, a region of the upper atmosphere where interactions between neutral and charged particles are responsible for many dynamic processes.

    The research team knew that in cooler regions of the sun, such as the interface region, not all gas particles are electrically charged. Some particles are neutral, and neutral particles aren’t subject to magnetic fields like charged particles are. Scientists had based previous models on a fully ionized plasma in order to simplify the problem. Indeed, including the necessary neutral particles was very computationally expensive, and the final model took roughly a year to run on the Pleiades supercomputer located at NASA’s Ames Research Center in Silicon Valley, and which supports hundreds of science and engineering projects for NASA missions.

    The model began with a basic understanding of how plasma moves in the sun’s atmosphere. Constant convection, or boiling, of material throughout the sun generates islands of tangled magnetic fields. When boiling carries them up to the surface and farther into the sun’s lower atmosphere, magnetic field lines rapidly snap back into place to resolve the tension, expelling plasma and energy. Out of this violence, a spicule is born. But explaining how these complex magnetic knots rise and snap was the tricky part.

    “Usually magnetic fields are tightly coupled to charged particles,” said Juan Martínez-Sykora, lead author of the study and a solar physicist at Lockheed Martin and the Bay Area Environmental Research Institute in Sonoma, California. “With only charged particles in the model, the magnetic fields were stuck, and couldn’t rise beyond the sun’s surface. When we added neutrals, the magnetic fields could move more freely.”

    Neutral particles provide the buoyancy the gnarled knots of magnetic energy need to rise through the sun’s boiling plasma and reach the chromosphere. There, they snap into spicules, releasing both plasma and energy. Friction between ions and neutral particles heats the plasma even more, both in and around the spicules.

    With the new model, the simulations at last matched observations from IRIS and the Swedish Solar Telescope; spicules occurred naturally and frequently. The 10 years of work that went into developing this numerical model earned scientists Mats Carlsson and Viggo H. Hansteen, both authors of the study from the University of Oslo in Norway, the 2017 Arctowski Medal from the National Academy of Sciences. Martínez-Sykora led the expansion of the model to include the effects of neutral particles.

    The scientists’ updated model revealed something else about how energy moves in the solar atmosphere. It turns out this whip-like process also naturally generates Alfvén waves, a strong kind of magnetic wave scientists suspect is key to heating the sun’s atmosphere and propelling the solar wind, which constantly bathes our solar system and planet with charged particles from the sun.

    “This model answers a lot of questions we’ve had for so many years,” De Pontieu said. “We gradually increased the physical complexity of numerical models based on high-resolution observations, and it is really a success story for the approach we’ve taken with IRIS.”

    The simulations indicate spicules could play a big role in energizing the sun’s atmosphere, by constantly forcing plasma out and generating so many Alfvén waves across the sun’s entire surface.

    “This is a major advance in our understanding of what processes can energize the solar atmosphere, and lays the foundation for investigations with even more detail to determine how big of a role spicules play,” said Adrian Daw, IRIS mission scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “A very nice result on the eve of our launch anniversary.”

    Related:

    IRIS Mission Overview
    New Space Weather Model Helps Simulate Magnetic Structure of Solar Storms

    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

     
  • richardmitnick 2:25 pm on August 9, 2016 Permalink | Reply
    Tags: , , NASA IRIS   

    From Goddard: “IRIS Spots Plasma Rain on Sun’s Surface” 

    NASA Goddard Banner

    NASA Goddard Space Flight Center

    [This post is dedicated to D.O., the family rocket scientist and gourmet cook. I hope he sees it.]

    Aug. 5, 2016
    Lina Tran
    kathalina.k.tran@nasa.gov
    NASA’s Goddard Space Flight Center, Greenbelt, Md.

    1
    No image caption. No image credit.

    On July 24, 2016, NASA’s Interface Region Imaging Spectrograph, or IRIS, captured a mid-level solar flare: a sudden flash of bright light on the solar limb – the horizon of the sun – as seen at the beginning of this video. Solar flares are powerful explosions of radiation. During flares, a large amount of magnetic energy is released, heating the sun’s atmosphere and releasing energized particles out into space. Observing flares such as this helps the IRIS mission study how solar material and energy move throughout the sun’s lower atmosphere, so we can better understand what drives the constant changes we can see on our sun.

    NASA IRIS spacecraft
    NASA/IRIS


    Credits: NASA’s Goddard Space Flight Center; Joy Ng, producer/IRIS/Lockheed Martin Solar and Astrophysics Laboratory

    As the video continues, solar material cascades down to the solar surface in great loops, a flare-driven event called post-flare loops or coronal rain. This material is plasma, a gas in which positively and negatively charged particles have separated, forming a superhot mix that follows paths guided by complex magnetic forces in the sun’s atmosphere. As the plasma falls down, it rapidly cools – from millions down to a few tens of thousands of kelvins. The corona is much hotter than the sun’s surface; the details of how this happens is a mystery that scientists continue to puzzle out. Bright pixels that appear at the end of the video aren’t caused by the solar flare, but occur when high-energy particles bombard IRIS’s charge-coupled device camera – an instrument used to detect photons.

    Related Link

    IRIS mission overview

    3
    This image of a sunspot, taken by NASA’s Transition Region and Coronal Explorer (TRACE) in Sept. 2000, showing the bright emission of the gas at about 1 million degrees, with the cooler material around 10,000 degrees showing up as dark, absorbing structures. NASA/TRACE

    4
    NASA/TRACE

    Tracking the complex processes within these layers of the solar atmosphere requires instrument and modeling capabilities that are within technological reach for the first time. IRIS is the first mission designed to simultaneously observe the range of temperatures specific to the chromosphere and transition region at very high spatial and temporal resolution — going beyond earlier missions that were lower resolution or did not cover a wide range of temperatures.

    IRIS also draws on state of the art computer modeling sophisticated enough to deal with the complexity of this area. In combination, IRIS’s resolution, wide temperature coverage and computer modeling will enable scientists to map plumes of solar material as they move throughout the region and to pinpoint where in their travels they gain energy and heat.

    The mission’s general science objectives are to answer the following questions:

    Which types of non-thermal energy dominate in the chromosphere and beyond?

    How does the chromosphere regulate mass and energy supply to the corona and heliosphere?

    How do magnetic flux and matter rise through the lower atmosphere and what role does flux emergence play in flares and mass ejections?

    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 9:33 am on October 17, 2014 Permalink | Reply
    Tags: , , , , NASA IRIS, ,   

    From SPACE.com: “NASA Probe Finds Nanoflares and Plasma ‘Bombs’ on Sun” 

    space-dot-com logo

    SPACE.com

    October 16, 2014
    Nola Taylor Redd

    The first results from a new NASA sun-studying spacecraft are in, and they reveal a complex and intriguing picture of Earth’s star.

    NASA’s Interface Region Imaging Spectrograph probe (IRIS) has observed ‘bombs’ of plasma on the sun, nanoflares that rapidly accelerate particles, and powerful jets that may drive the solar wind, among other phenomena, five new studies report.

    iris
    The completed IRIS observatory with solar arrays destroyed prior to launch. Credit: NASA

    While spacecraft can enter planetary atmospheres, they cannot fly through the outer atmosphere of the sun, where temperatures reach 3.5 million degrees Fahrenheit (2 million degrees Celsius). Probes like IRIS instead must study the star from a safe distance. Unlike previous instruments, IRIS can take far more detailed observations of the sun, capturing observations of regions only about 150 miles (240 kilometers) wide on a time scale of just a few seconds.

    “The combination of enhanced spatial and spectral resolution, [which are] both three to four times better than previous instruments, allows a much closer look [at the sun’s atmosphere],” Hardi Peter of the Max Planck Institute for Solar System Research in Germany told Space.com by email. Peter was the lead author on a study of hot plasma ‘bombs’ on the sun.

    Nanoflare acceleration

    The surface of the sun, or photosphere, is the region visible to human eyes. Above the photosphere lie the hotter chromosphere and transition regions, which emit ultraviolet light that can only be observed from space. This is because Earth’s atmosphere absorbs most of this radiation before it reaches land-based instruments. The outer part of the solar atmosphere is called the corona.

    While much of the sun’s energy is generated in its core through hydrogen fusion, temperatures rise in the exterior layers moving out farther from the heat source. This means that something is powering that outer region, and scientists think the magnetic fields generated by the churning solar plasma provide at least part of the answer.

    In emerging active regions, magnetic fields rise through the surface into the upper atmosphere, like a string pulled upward. When the energy carried by the field lines becomes too great, they snap, disconnecting from one another and reconnecting with other broken field lines in a process known as magnetic reconnection.

    Paola Testa, of the Harvard-Smithsonian Center for Astrophysics, led a team that used IRIS to study the footprints of these loops, where he found that the intensity changed over a span of 20 to 60 seconds. Investigating possible causes, Testa determined that the variations were consistent with simulations of electrons generated from coronal nanoflares.

    “Nanoflares are short heating events releasing amounts of energy about a billion times smaller than large flares,” Testa said.

    fl
    Ultraviolet image of an active region on the sun, showing plasma at temperatures of 140,000 degrees. This image was captured by NASA’s IRIS spacecraft on Dec. 6, 2013.
    Credit: IRIS: LMSAL, NASA. Courtesy Bart De Pontieu, Lockheed Martin Solar & Astrophysics Laboratory

    Although smaller than their larger cousins, nanoflares occur more frequently, likely due to magnetic reconnection. Energy released during magnetic reconnection accelerates some particles to high energies, where they are emitted as radio waves and the highest energy X-rays. Scientists have observed these signals in medium and large flares, but for nanoflares, the rapidly moving electrons are too faint to detect directly using current instrumentation.

    “That is why our observations in the ultraviolet are particularly interesting,” Testa said. “They provide an alternative way to study these accelerated particles, although not directly observing them.”

    Hot bombs in cool regions

    In the cooler photosphere of the sun, where temperatures reach approximately 10,000 degrees F (5,500 degrees C), the magnetic fields convert a huge amount of energy from the magnetic energy stored in the field into thermal energy, heating the plasma. According to Peter, the amount of energy released would be enough to provide electric power to Germany for 8,000 years. The change creates a pocket of gas heated up to 180,000 degrees F (100,000 degrees C) in the middle of the cooler surface region.

    These pockets, or “bombs,” eject plasma. Upward-moving material probably disperses into the hot corona, Peter said, while the downward-moving plasma is quickly cooled to reach the same material as the rest of the photosphere, blending back in to the surrounding material.

    Previously, scientists spotted no indications that energy-releasing events in the photosphere would result in the high temperature spikes in pockets within the photosphere. The energy output required to heat the dense gas was thought to be too high to be obtainable.

    “With these new results that show the existence of hot pockets in cool gas, we have to either revise the amount of energy that can be supplied deep in the photosphere, or we have to think of a clever yet unknown mechanism to heat the cool, dense gas rapidly to these high temperatures,” Peter said.

    Do the twist

    In addition to disconnecting and reconnecting, the magnetic fields on the sun also twist. As the twisting field lines move away from the surface at 19 to 62 miles (30 to 100 km) per second, the nearby transition regions brighten to temperatures of up to 144,000 degrees F (80,000 C), far above the chromosphere’s average temperature of 7,800 degrees F (4,000 degrees C).

    IRIS’s detailed study of the sun revealed that the twists are far more widespread than suggested by previous studies. These twists occur in every magnetic region, both quiet and active. Observations of twists were made at IRIS’s maximum resolution, but other unresolved small-scale motions in the observations seemed to indicate the presence of even smaller twists in the field lines.

    Although the current data does not allow the scientists to determine the twists’ cause, IRIS science lead and first author Bart De Pontieu, of Lockheed Martin Solar and Astrophysics Laboratory, said that the twisting is most likely a signature of the so-called Alfven waves. These “magnetic waves [are] not unlike the waves that are generated after plucking a guitar string,” he said. The source of these waves also remains unknown.

    Another potential source could be the strong convective, or “boiling,” motions at the sun’s surface.

    “Numerical simulations of the solar convection suggest that torsional [twisting] motions can be generated, kind of like when you drain a bathtub, and you see swirling motions as the water drains out,” De Pontieu said.

    Scientists have several hypotheses for how the solar atmosphere is heated, and De Pontieu said the new observations provide constraints on these theories.

    “In particular, they provide support for models in which Alfven waves do much of the heavy lifting in the solar atmosphere,” he said.

    sun
    In its first released image of the sun, IRIS captured a view of the solar atmosphere. Credit: NASA

    As the closest and brightest star, the sun has been studied throughout history. Based on indirect evidence from Skylab and other missions in the 1970s and 1980s, astronomer Uri Feldman, of the Naval Research Laboratory, proposed the existence of “unresolved fine structures” (UFS), an important solar atmospheric component in the transition region between the chromosphere and the corona. Using IRIS’s instruments, a team lead by Viggo Hansteen, of the University of Oslo in Norway, determined that a series of low-lying magnetic loops constitute these UFS, settling a decades-long debate regarding their existence.

    The loops of the magnetic field light up for short spans of time, perhaps a minute, when the plasma in the loops are heated, either due to magnetic reconnection or the dissipation of Alfven waves. During magnetic reconnection, plasma is accelerated to 2 to 3 times the speed of sound. Sometimes the loops form in isolation; other times they are concentrated in a nest of loops.

    The debate regarding the loops’ existence stemmed in part from questions about the plasma; scientists questioned whether or not all of the plasma in the transition region was thermally connected to the corona. The presence of the low-lying loops in the transition region confirms that plasma reaching temperatures of 180,000 degrees F (100,000 degrees C) are heated by from the loops rather than the corona.

    Although the loops themselves don’t heat the corona, Hansteen said that they are probably heated with the same mechanism, though with a different response due to their higher density.

    “It is likely that these differences will allow us to focus more clearly on the nature of the unknown heating events themselves,” Hansteen said.

    Powering the solar wind

    The solar wind drives particles and plasma from the sun through the solar system. When the particles collide with Earth’s magnetic field, they produce beautiful auroras, and have the potential to interfere with satellites and communication systems. But the source of the solar wind remains a mystery.

    The fast-moving solar wind travels hundreds of kilometers per second, carrying low-density materials. Previous instruments lacked the ability to study the small-scale regions thought to be responsible for the wind with the precision necessary to understand it.

    Scientists suspect that the solar wind originates from the bright network structures on the sun, appearing as bright lanes enclosing dark cells. These lanes flow outward from the sun, funneled by the magnetic structure, and eventually merge together into a single solar wind stream that flows steadily from the sun.

    A team lead by Hui Tian, of the Harvard-Smithsonian Center for Astrophysics, identified high-speed, intermittent jets in what scientists think is the solar wind source region, making these jets likely candidates for the initial stage of the solar wind. Rather than producing a steady outflow, the jets are sporadic, accelerating particles to speeds up of to 155 miles per second (250 km/s).

    “If these jets really are the nascent solar wind, then solar wind models must be updated to produce these intermittent, high-speed and small-scale outflows in the interface region,” Tian said.

    “If the answer is no, at least the impact of these jets on the still-not-observed nascent solar wind outflow should be carefully evaluated, because these jets are the most prominent dynamic feature in the believed solar wind source region,” he said.

    All five papers, along with a perspective piece by Louise Harra of the University College London, were published online today (Oct. 16) in the journal Science.

    See the full article, with video, here.

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