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  • richardmitnick 11:18 am on August 31, 2016 Permalink | Reply
    Tags: , , , Monitoring Holes in the Sun’s Corona, NASA SDO,   

    From AAS NOVA: “Monitoring Holes in the Sun’s Corona” 

    AASNOVA

    American Astronomical Society

    31 August 2016
    Susanna Kohler

    1
    A view of a hole in the Sun’s corona from the Solar Dynamics Observatory. A new study tracks the trend of coronal holes from 1975 to 2014. [NASA/SDO/helioviewer]

    NASA/SDO
    NASA/SDO

    2
    Coronal holes form where magnetic field lines open into space (B) instead of looping back to the solar surface (A). [Sebman81]

    Source of the Fast Solar Wind

    As a part of the Sun’s natural activity cycle, extremely low-density regions sometimes form in the solar corona. These “coronal holes” manifest themselves as dark patches in X-ray and extreme ultraviolet imaging, since the corona is much hotter than the solar surface that peeks through from underneath it.

    Coronal holes form when magnetic field lines open into space instead of looping back to the solar surface. In these regions, the solar atmosphere escapes via these field lines, rapidly streaming away from the Sun’s surface in what’s known as the “fast solar wind”.

    Coronal Holes Over Space and Time

    Automated detection of coronal holes from image-based analysis is notoriously difficult. Recently, a team of scientists led by Ken’ichi Fujiki (ISEE, Nagoya University, Japan) has developed an automated prediction technique for coronal holes that relies instead on magnetic-field data for the Sun, obtained at the National Solar Observatory’s Kitt Peak between 1975 and 2014. The team used these data to produce a database of 3335 coronal hole predictions over nearly 40 years.

    4
    Latitude distribution of 2870 coronal holes (each marked by an x; color indicates polarity), overlaid on the magnetic butterfly map of the Sun. The low-latitude coronal holes display a similar butterfly pattern, in which they move closer to the equator over the course of the solar cycle. Polar coronal holes are more frequent during solar minima. [Fujiki et al. 2016]

    Examining trends in the coronal holes’ distribution in latitude and time, Fujiki and collaborators find a strong correlation between the total area covered by low-latitude coronal holes (holes closer to the Sun’s equator) and sunspot activity. In contrast, the total area of high-latitude coronal holes (those near the Sun’s poles) peaks around the minimum in each solar cycle and shrinks around each solar maximum.

    Predicting the Impact of the Solar Wind

    Why do these observations matter? Coronal holes are the source of the fast solar wind, so if we can better predict the frequency and locations of coronal holes in the future, we can make better predictions about how the solar wind might impact us here on Earth.

    5
    Periodicity of high-latitude (orange) and low-latitude (blue) coronal-hole areas, and periodicity of galactic cosmic rays detected at Earth (black). The cosmic rays track the polar coronal-hole area behavior with a 1-year time lag. [Fujiki et al. 2016]

    In one example of this, Fujiki and collaborators show that there’s a distinct correlation between polar coronal-hole area and observed galactic cosmic rays. Cosmic rays from within our galaxy have long been known to exhibit a 22-year periodicity. Fujiki and collaborators show that the periodicity of the galactic cosmic-ray activity tracks that of the polar coronal-hole area, with a ~1-year lag time — which is equivalent to the propagation time of the solar wind to the termination shock.

    Polar coronal holes are therefore a useful observable indicator of the dipole component of the solar magnetic field, which modulates the incoming cosmic rays entering our solar system. This coronal hole database will be a useful tool for understanding the source of solar wind and the many ways the wind influences the Earth and our solar system.

    Citation

    K. Fujiki et al 2016 ApJ 827 L41. doi:10.3847/2041-8205/827/2/L41

    See the full article here .

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  • richardmitnick 11:24 am on August 26, 2016 Permalink | Reply
    Tags: , , , NASA SDO, ,   

    From Ethan Siegel: “NASA’s Revived STEREO-B Could Save Us From A Trillion Dollar Disaster” 

    From Ethan Siegel

    Aug 26, 2016

    1
    An X-class solar flare erupted from the Sun’s surface in 2012. At the time, it was the largest flare in five years. Image credit: NASA/Solar Dynamics Observatory (SDO) via Getty Images.

    Solar flares are spectacular sights from space, where giant streams of plasma are ejected from the Sun’s interior at incredibly high energies and speeds. They stream through the Solar System, usually traveling the Sun-Earth distance in three days or fewer. While this intense, ionized radiation would be dangerous to an astronaut in the depths of space, for the most part our planet’s magnetic field and atmosphere shields our bodies from any harm. The magnetic field funnels the radiation away from Earth, only enabling it to strike in a region around the poles, while the atmosphere ensures that the charged particles themselves don’t make it down to the surface. But their changing magnetic fields do, and that’s enough to induce currents in electrical wires, circuits and loops. Thankfully, now that NASA’s STEREO-A and STEREO-B spacecraft are both alive simultaneously, we’ll get the earliest warnings possible if a potential catastrophe is headed our way.

    NASA/STEREO spacecraft
    NASA/STEREO spacecraft

    You might think this is a rare event, but it’s not at all rare like a meteor striking Earth is rare. It’s not even “rare” in the sense that seeing a supernova from Earth is rare; an ultra-high-energy solar flare directed right at Earth is a question of when, not if. Imagine a beautiful, clear day. The Sun is shining, the skies are clear, and you couldn’t ask for a nicer day. All of a sudden, the Sun itself appears to brighten, just for a brief amount of time, like it released an extra burst of energy. That night, some 17 hours later, the most spectacular auroral display ever brightens the night in a way you never imagined.

    2
    Sunspots are often, but not always, portents of where a solar flare is most likely to occur. Image credit: Shahrin Ahmad (ShahGazer), Kuala Lumpur, Malaysia.

    Workers across the United States awaken at 1 a.m., because the sky is as bright as the dawn. Aurorae illuminate the skies as far south as the Caribbean, beneath the Tropic of Cancer. And long, electricity-carrying wires spark, start fires and even operate and send signals when there’s no electricity! This even includes, believe it or not, when they aren’t plugged in. This isn’t a science-fiction scenario; this is history. This is what a catastrophic Solar Storm looks like, and this actually occurred exactly as described in 1859.

    3
    A significant coronal mass ejection from the Sun that (thankfully) was not directed at Earth. Image credit: NASA / GSFC / SDO.

    NASA/SDO
    NASA/SDO

    The way this actually happens is that the Sun, rather than being this constant ball of nuclear fire in the sky, has an active surface, complete with an intricate magnetic structure, temperature variations, sunspots, and occasional flares and mass ejections. For reasons we don’t completely understand, the Sun’s activity levels ebb and peak on an 11-year timescale known as the Solar Cycle, and the transition between 2013/2014 was anticipated to have been the peak of our current cycle. We’re more likely to see larger numbers of flares, as well as stronger-than-average flares, during the peak years, but in reality they can occur at any time.

    Typically (but not always), these flares pose no danger to anything here on Earth, for a variety of reasons.

    1.) Most solar flares are not directed anywhere near the Earth. Space is a big place, and even at our relatively close distance of 93 million miles (or 150 million km) from the Sun, that’s a long way away. Even though most sunspots occur near the solar equator, more than 95% of flares and ejections, when they occur, never impact our planet at all. But there is that pesky few percent that does impact us.

    4
    A representation of how most ionized particles are diverted away from Earth by our magnetic field. Image credit: NASA.

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

    2.) Most flares are too small, too slow and sub-optimally aligned to get past the Earth’s magnetic field. Our magnetic field is awesome! Sure, it might be less than 1 G (gauss) at the surface (or 0.0001 T — for Tesla — for you mks sticklers out there), barely enough to deflect your compass needles towards the magnetic poles. But the field extends far into space, and the matter ejected in a solar flare are almost exclusively charged particles, which typically move at speeds of only a million miles an hour.

    These particles are bent by our magnetic field (as are all charged particles moving through a magnetic field) and will mostly be deflected away from the Earth. The ones that are bent into the Earth will crash into our upper atmosphere; this is the cause of nearly all auroral events.

    5
    The atmospheric effects of the aurorae, as seen from space. Image credit: NASA / ISS expedition crew 23.

    3.) Our atmosphere is sufficiently thick to prevent these charged particles from irradiating us. Even if the flare moves quickly (or at about five million miles-per-hour), is huge (containing billions of tons of matter), and is aimed directly at us, the charged particles will never make it through our atmosphere, down to the surface. In fact, they peter out to practically nothing nearly 50 km above the Earth’s surface, far higher than any mountains or even that the heights airliners reach. Unless you’re in space (for some reason) at the time, you won’t receive any more radiation than you normally would, and there is no biological risk.

    But there is one real risk, and it’s a consequence of our physical laws of electromagnetism.

    6
    The anatomy of the dangers of a solar flare. Image credit: NASA.

    A charged particle is bent as it moves through a magnetic field because of the connection between electricity and magnetism. But that same connection means that a change in electric currents — which are made by the motion of charged particles — create changing magnetic fields. And if you have a changing magnetic field either around a wire or through a loop or coil of wire, you will generate electric currents!

    So while there may not be a danger to you, there is a huge danger to electronics, ranging from automobiles to transformers to — most frighteningly of all — the entire power grid! That’s the real danger of a solar storm: an event similar to the 1859 Carrington event could cause anywhere between an estimated $1-to-$2 trillion of property damage, mostly due to electrical fires and damage to our infrastructure.

    7
    Depiction of 1859 Carrington event.Politesseo

    8
    A number of NASA satellites throughout the solar system. Image credit: NASA.

    With the space weather satellites we had up just a few years ago, we would have about a half-day’s warning to shut down our power stations and voluntarily shut off the grid in the event of such a flare. With STEREO-A and STEREO-B operating simultaneously, however, we can know as soon as the flare occurs, giving us up to three days of lead time. These events cannot be predicted in advance, and neither can their interaction with the interplanetary-and-Earth’s magnetic field, so you must never listen to fear-mongers who tell you a catastrophic solar flare is imminent; we can only be prepared to react when one is detected.

    9
    The combination of NASA’s STEREO-A (ahead) and STEREO-B (behind), combined with the solar dynamics observatory (SDO) near Earth gives us a full view of the entire photosphere of the Sun at once. Image credit: NASA.

    Ideally, we’d be able to either upgrade the grid or to simply install a sufficient amount of electrical grounding, but practically, the first option is a long-term project that no one is working on, and the second one is continuously thwarted by thievery of copper wire. Power stations and substations simply do not maintain enough grounding due to this thievery, and there’s no known antidote to that, since if death-by-electrocution isn’t enough of a deterrent, what will be?

    There’s no need to be afraid of these things, but you do need to be prepared. If an ultra-massive, fast-moving coronal mass ejection ever heads directly towards Earth, you are literally taking your life into your hands if you do not shut down and unplug all of your electronic devices — and your power companies deliberately black out your neighborhood — until the storm passes. Long-distance wires, power stations and substations and the major components of the electrical grid itself will be at the greatest risk, as they will have huge direct currents (in systems designed only to carry AC) induced in them. The smartest move for those components, quite honestly, might be to sever the wires. That’s the only surefire way we have of personally safely dealing with things now.

    But you should also keep in mind that there’s only about a 1% chance we’ll get a large, powerful Earth-directed flare in any given year, and only about a 0.2% of getting an event like we did in 1859. So be aware, be informed and know how to deal with it if it happens, but don’t lose any sleep over it! Instead, your best bet is — when applicable — to go outside and enjoy the auroral show!

    This article is dedicated to Jake Morgan, whose fascination with solar storms led him to write his first book: Sunburned. Jake recently suffered a catastrophic accident and is undergoing significant time in the ICU; you can help support his GoFundMe here.

    See the full article here .

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    “Starts With A Bang! is a blog/video blog about cosmology, physics, astronomy, and anything else I find interesting enough to write about. I am a firm believer that the highest good in life is learning, and the greatest evil is willful ignorance. The goal of everything on this site is to help inform you about our world, how we came to be here, and to understand how it all works. As I write these pages for you, I hope to not only explain to you what we know, think, and believe, but how we know it, and why we draw the conclusions we do. It is my hope that you find this interesting, informative, and accessible,” says Ethan

     
  • richardmitnick 7:13 pm on April 18, 2016 Permalink | Reply
    Tags: , , NASA SDO,   

    From NASA SDO: “NASA’s SDO Captures Images of a Mid-Level Solar Flare” 

    NASA image
    NASA

    NASA/SDO
    NASA/SDO

    April 18, 2016
    Karen C. Fox
    NASA’s Goddard Space Flight Center, Greenbelt, Md.

    The sun emitted a mid-level solar flare, peaking at 8:29 pm EDT on April 17, 2016. NASA’s Solar Dynamics Observatory, which watches the sun constantly, captured an image of the event. Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth’s atmosphere to physically affect humans on the ground, however — when intense enough — they can disturb the atmosphere in the layer where GPS and communications signals travel.

    1
    NASA’s Solar Dynamics Observatory captured this imagery of a solar flare – as seen in the bright flash – around 8:30 p.m. EDT on April 17, 2016. A loop of solar material can also be seen rising up off the right limb of the sun. Credits: NASA/SDO/Goddard

    NOAA’s Space Weather Prediction Center states that “moderate radio blackouts were observed” during the peak of the flare. Such radio blackouts are only ongoing during the course of a flare, and so they have since subsided. NOAA’s Space Weather Prediction Center is the U.S. government’s official source for space weather forecasts, watches, warnings and alerts.

    This flare is classified as an M6.7 class flare. M-class flares are a tenth the size of the most intense flares, the X-class flares. The number provides more information about its strength. An M2 is twice as intense as an M1, an M3 is three times as intense, etc.

    This flare came from an area of complex magnetic activity on the sun – known as an active region, and in this case labeled Active Region 2529 – which has sported a large dark spot, called a sunspot, over the past several days. This sunspot has changed shape and size as it slowly made its way across the sun’s face over the past week and half. For much of that time, it was big enough to be visible from the ground without magnification and is currently large enough that almost five Earths could fit inside. This sunspot will rotate out of our view over the right side of the sun by April 20, 2016. Scientists study such sunspots in order to better understand what causes them to sometimes erupt with solar flares.

    What is a solar flare?

    2
    A black spot on the sun is visible in the upper right of this image captured by NASA’s Solar Dynamics Observatory. Such spots are evidence that this is an area of complex magnetic activity on the sun, which can sometimes lead to solar eruptions sending light and radiation out into space. This region produced a solar flare at 8:29 p.m. EDT on April 17, 2016.
    Credits: NASA/SDO/Goddard

    For answers to this and other space weather questions, please visit the Space weather Frequently Asked Questions page.

    Related Link:

    View Past Solar Activity

    See the full article here .

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    The National Aeronautics and Space Administration (NASA) is the agency of the United States government that is responsible for the nation’s civilian space program and for aeronautics and aerospace research.

    President Dwight D. Eisenhower established the National Aeronautics and Space Administration (NASA) in 1958 with a distinctly civilian (rather than military) orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29, 1958, disestablishing NASA’s predecessor, the National Advisory Committee for Aeronautics (NACA). The new agency became operational on October 1, 1958.

    Since that time, most U.S. space exploration efforts have been led by NASA, including the Apollo moon-landing missions, the Skylab space station, and later the Space Shuttle. Currently, NASA is supporting the International Space Station and is overseeing the development of the Orion Multi-Purpose Crew Vehicle and Commercial Crew vehicles. The agency is also responsible for the Launch Services Program (LSP) which provides oversight of launch operations and countdown management for unmanned NASA launches. Most recently, NASA announced a new Space Launch System that it said would take the agency’s astronauts farther into space than ever before and lay the cornerstone for future human space exploration efforts by the U.S.

    NASA science is focused on better understanding Earth through the Earth Observing System, advancing heliophysics through the efforts of the Science Mission Directorate’s Heliophysics Research Program, exploring bodies throughout the Solar System with advanced robotic missions such as New Horizons, and researching astrophysics topics, such as the Big Bang, through the Great Observatories [Hubble, Chandra, Spitzer, and associated programs. NASA shares data with various national and international organizations such as from the [JAXA]Greenhouse Gases Observing Satellite.

     
  • richardmitnick 7:59 am on January 26, 2016 Permalink | Reply
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    From SPACE.com: “Mysteriously Powerful Particles from Solar Explosions Unveiled in New Study” 

    space-dot-com logo

    SPACE.com

    January 25, 2016
    Calla Cofield

    Solar eruption 2012 by NASA's Solar Dynamic Observatory SDO
    A photo of a solar eruption from Oct. 14, 2012, as seen by NASA’s Solar Dynamic Observatory. Credit: NASA/SDO

    NASA SDO
    NASA/SDO

    A couple of times a month — sometimes more, sometimes less — an explosion goes off on the surface of the sun, releasing energy that’s equal to millions of hydrogen bombs.

    Mind boggling as that number is, this tremendous energy output cannot explain how material that is spit out by these explosions gets ramped up to nearly the speed of light. It’s like expecting a golf cart motor to power a Ferrari.

    In a new study, researchers provide a first-of-its-kind look under the hood of these solar eruptions, taking specific aim at the physical process that accelerates the superfast particles.

    Explosions on the sun

    There are currently 18 NASA space missions dedicated to studying our nearest star and its effect on the solar system. Some of these satellites stare directly at the sun almost nonstop, providing a 24/7 stream of images of the sun’s swirling, churning surface.

    When a solar eruption happens, these satellites also see the incredibly bright flashes of light that are called solar flares. Occasionally, the eruptions also hurl a cloud of extremely hot and electrically charged gas (called plasma) out into space. The expelled plasma is called a coronal mass ejection, or CME for short.

    A solar explosion releases roughly the same amount of energy that would come from “millions of 100-megaton hydrogen bombs,” according to NASA, where one hundred megatons equal to one hundred million metric tons of TNT.

    While that certainly sounds impressive, it’s hard to imagine something so enormous. The best way to understand the colossal nature of these events might be to consider an image taken by NASA that shows a particularly massive CME. For comparison, a snapshot of the Earth (to scale) is placed next to this great, flaming ribbon. The planet looks like a daisy in the path of a flamethrower.

    A solar explosion releases roughly the same amount of energy that would come from “millions of 100-megaton hydrogen bombs,” according to NASA, where one hundred megatons equal to one hundred million metric tons of TNT.

    Shockingly fast

    When an airplane breaks the sound barrier — physically overtaking the sound waves traveling in front of it — it creates a shock wave, and a deafening sonic boom. The boom is evidence that the shock wave is a source of energy.

    Bin Chen, a researcher at the Harvard-Smithsonian Center for Astrophysics is the lead author on a new research paper that provides the first solid observational evidence that ultraspeedy particles released during a solar eruption are accelerated by a kind of stationary shock wave called a “termination shock.”

    One of the intriguing elements of solar eruptions is that, unlike most explosions on Earth, they aren’t chemically driven. Rather, these sunshine bombs are detonated by a rapid release of magnetic energy. The same force that makes a magnet stick to a refrigerator or makes a compass needle point north is also responsible for these massive belches of light and material.

    The solar eruptions that create solar flares and CMEs occur when one of the sun’s magnetic-field lines break, and rapidly reconnects, near the surface. During the explosion, plasma is flung out into space, but others go back down toward the surface at incredibly high speeds, where they crash into more magnetic-field loops — kind of like a waterfall crashing into the surface of a pond. At the point of collision, a termination shock forms in the electrically charged plasma.

    “Charged particles that cross a [termination] shock can pick up the energy from the shock and get faster and faster. That’s how shock acceleration works,” Bin told Space.com.

    Chen and his coauthors saw evidence of this termination shock during a solar flare on March 3, 2012, using the Karl G. Jansky Very Large Array (VLA) in New Mexico.

    NRAO VLA
    Karl G. Jansky Very Large Array (VLA)

    The recently upgraded telescope was beneficial for two reasons. First, it detects radio waves, which means it isn’t overwhelmed by the brightest flashes of light emitted during a solar flare. But looking at a solar flare radio frequencies does reveal the particles accelerated by the termination shock.

    Second, the telescope can effectively take around 40,000 images per second. It does this by capturing thousands of radio frequencies at the same time. The frequencies are then separated into individual “images.” Chen told Space.com that in order to see termination shock in action, it was necessary to collect that many images for about 20 minutes.

    “So if you do the math, that’s millions and millions of images [you need] in order to extract the information,” Chen said. “That’s a new capability provided by the upgraded VLA.”

    Chen said the new findings don’t necessarily mean that termination shocks are responsible for accelerating particles in all solar flares. He said he and his colleagues would like to conduct further observations to find out if this is the case in all shocks, or only a subset.

    The termination shock explanation has been part of the “standard” solar-flare theory for years, but there hasn’t been “convincing” observational evidence to back it up, Chen said. Chen’s comment was confirmed by Edward DeLuca, a senior astrophysicist at the Smithsonian Astrophysical Observatory, which is part of the Harvard-Smithsonian Center for Astrophysics (DeLuca works in the same department as Chen, but was not involved with the new research.)

    “[The new result] reveals that we’re on the right track with the standard-flare model,” DeLuca said.

    Look out for powerful particles

    All those NASA satellites studying the sun are not just working to create mesmerizing images; they’re also there to help protect Earth. Solar flares and coronal mass ejections pose a hazard to the planet. The particles they eject can damage satellites and solar panels, and could pose a serious threat to astronauts doing spacewalks outside the International Space Station, on the moon or Mars.

    They can even cause surges in power grids on the ground. In 1989, a CME caused a blackout across the entire province of Quebec, Canada.

    The superfast particles are of particular worry, because their high speeds mean they can penetrate more layers of material than their “slower” counterparts. When those particles penetrate a piece of solid-state equipment, they can cause a “bit flip” — which could not only damage the equipment but also change what it does.

    “If that little flip of the bit means a computer command that normally says, ‘keep taking snapshots of the sun,’ instead says ‘shut down the spacecraft,’ that’s bad,” Young said. “So a lot of times, if there is a large particle event, spacecraft operators will often put their spacecraft into what’s called a ‘safe mode.'”

    That reaction has to happen fast. Light can travel from the sun to the earth in 8 minutes, so the solar energetic particles can reach an orbiting satellite in about 10 to 20 minutes, Young said. Coronal mass ejections leave a little more time, but a delayed response can mean serious consequences.

    For that reason, scientists are trying to get better at predicting when solar flares and CME’s will occur and how intense they will be.

    DeLuca said the new understanding of termination shock will not, most likely, be immediately useful for improving forecasting of solar explosions. But it is a piece of the solar-flare puzzle, and he said it will be incorporated into “next-generation” solar-weather technology and prediction techniques. It’s one more step toward helping humans ride out the solar storm.

    See the full article here .

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  • richardmitnick 8:35 pm on December 13, 2015 Permalink | Reply
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    From SPACE.com: “Giant ‘Hole’ in Sun Is 50 Earths Wide” 

    space-dot-com logo

    SPACE.com

    October 15, 2015 [This was put up today 12.13.15]
    Sarah Lewin

    1
    A photo of the sun from NASA’s orbiting Solar Dynamics Observatory reveals an enormous coronal hole — a gap in the sun’s outer layer and magnetic field the size of 50 Earths. The image was captured Oct. Credit: NASA/SDO

    NASA SDO
    NASA/SDO

    The sun has sprung a leak: A hole in the topmost layer of the sun and its magnetic field, the size of 50 Earths, is letting loose an ultrafast solar wind that has kicked off several nights of auroras down on Earth.

    A new image, from NASA’s orbiting Solar Dynamics Observatory, reveals the enormous hole as it was Oct. 10, taken at an ultraviolet wavelength unseen by the human eye. To an ordinary observer, the gaping hole would be invisible, though you should NEVER stare at the sun because serious eye damage can result.

    The gap in the sun’s magnetic field lets out a stream of particles traveling at up to 500 miles (800 kilometers) per second, kindling a days-long geomagnetic storm upon hitting Earth.

    Coronal holes, like the one that materialized last week, normally form over the sun’s poles and lower latitudes, more often when the sun is at a less active point in its 11-year cycle. They are areas within the sun’s outermost layer, called its corona, which are lower-density and cooler — that, plus the weakened magnetic field, lets the plasma and charged particles that make up the corona stream out more easily in a solar wind. If aimed toward Earth, that spells the makings of a geomagnetic storm: a phenomenon that can affect power and navigation for satellites orbiting the Earth as well as radio communication.

    Temp 1
    A Solar Dynamics Observatory image published by the National Oceanic Atmospheric Administration reveals the huge coronal hole as it was yesterday [10.14.15]. Continuing its march solar west (to the right), the hole is still releasing an extra-fast solar wind in Earth’s direction. Credit: NASA/SDO

    Another side effect of a geomagnetic storm is enhanced northern lights: the glowing auroras that often form in the night sky over the northernmost reaches of the planet grow much brighter and can even extend much farther south than usual. (Last week, the National Oceanic and Atmospheric Administration’s [NOAA] Space Weather Prediction Center in Boulder, Colorado, initially predicted auroras to be visible as far down as Pennsylvania, Iowa and Oregon, although they didn’t ultimately appear quite so low.) Geomagnetic storms and auroras can also be caused by other sun phenomena, such as solar flares and coronal mass ejections, which both blast the corona’s material outward because of increased magnetic activity.

    As the coronal hole continues its slow march westward on the sun’s surface (to the right, from Earth’s perspective), solar winds will stay strong, NOAA officials said in a statement, which may lead to additional minor geomagnetic storming. Thus, bright auroras will likely continue — at least around the Arctic Circle.

    See the full article here .

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  • richardmitnick 1:58 pm on November 18, 2015 Permalink | Reply
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    From AAS NOVA: “Eruptions from the Sun” 

    AASNOVA

    Amercan Astronomical Society

    18 November 2015
    Susanna Kohler

    1
    An image captured of the Sun by the Solar Dynamics Observatory’s Atmospheric Imaging Assembly, a few hours after a coronal mass ejection erupted off of the Sun’s northwest limb. [NASA/SDO/AIA]

    1
    Gif of a movie of the CME, taken by the Solar Dynamics Observatory’s Atmospheric Imaging Assembly at a wavelength of 304Å. The original movie can be found in [cited] the article.

    The Sun often exhibits outbursts, launching material from its surface in powerful releases of energy. Recent analysis of such an outburst — captured on video by several Sun-monitoring spacecraft — may help us understand the mechanisms that launch these eruptions.

    Many Outbursts

    Solar jets are elongated, transient structures that are thought to regularly release magnetic energy from the Sun, contributing to coronal heating and solar wind acceleration. Coronal mass ejections (CMEs), on the other hand, are enormous blob-like explosions, violently ejecting energy and mass from the Sun at incredible speeds.

    But could these two types of events actually be related? According to a team of scientists at the University of Science and Technology of China, they may well be. The team, led by Jiajia Liu, has analyzed observations of a coronal jet that they believe prompted the launch of a powerful CME.

    Observing an Explosion

    An army of spacecraft was on hand to witness the event on 15 Jan 2013 — including the Solar Dynamics Observatory (SDO), the Solar and Heliospheric Observatory (SOHO), and the Solar Terrestrial Relations Observatory (STEREO).

    NASA SDO
    NASA/SDO

    NASA SOHO
    NASA/SOHO

    NASA STEREO spacecraft
    NASA/STEREO

    The instruments on board these observatories captured the drama on the northern limb of the Sun as, at 19:32 UT, a coronal jet formed. Just eight minutes later, a powerful CME was released from the same active region.

    The fact that the jet and CME occurred in the same place at roughly the same time suggests they’re related. But did the initial motions of the CME blob trigger the jet? Or did the jet trigger the CME?

    Tying It All Together

    In a recently published study, Liu and collaborators analyzed the multi-wavelength observations of this event to find the heights and positions of the jet and CME. From this analysis, they determined that the coronal jet triggered the release of material to form the CME, which then erupted into space — with the jet at its core — at speeds of over 1000 km/s.

    Based on observed clues of the magnetic field configurations, the team has put together a theory for how this event unfolded. They believe that sudden magnetic reconnection in an active region accelerated plasma to form a large-scale coronal jet. This burst of energy also provided a push on a blob of gas, threaded with magnetic field lines, that lay above the jet. The blob then rose, and when the field lines broke, it was released as a CME with the jet at its core.

    Citation

    Jiajia Liu et al 2015 ApJ 813 115. doi:10.1088/0004-637X/813/2/115

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  • richardmitnick 12:47 pm on May 22, 2015 Permalink | Reply
    Tags: , NASA SDO,   

    From NASA: “Coronal Loops Over a Sunspot Group” 

    NASA

    NASA

    May 22, 2015
    Sarah Loff

    1
    Image Credit: NASA SDO

    The Atmospheric Imaging Assembly (AIA) instrument aboard NASA’s Solar Dynamics Observatory (SDO) images the solar atmosphere in multiple wavelengths to link changes in the surface to interior changes. Its data includes images of the sun in 10 wavelengths every 10 seconds. When AIA images are sharpened a bit, such as this AIA 171Å channel image, the magnetic field can be readily visualized through the bright, thin strands that are called “coronal loops”. Loops are shown here in a blended overlay with the magnetic field as measured with SDO’s Helioseismic and Magnetic Imager underneath. Blue and yellow represent the opposite polarities of the magnetic field. The combined images were taken on Oct. 24, 2014, at 23:50:37 UT.

    NASA SDO
    SDO

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    The National Aeronautics and Space Administration (NASA) is the agency of the United States government that is responsible for the nation’s civilian space program and for aeronautics and aerospace research.

    President Dwight D. Eisenhower established the National Aeronautics and Space Administration (NASA) in 1958 with a distinctly civilian (rather than military) orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29, 1958, disestablishing NASA’s predecessor, the National Advisory Committee for Aeronautics (NACA). The new agency became operational on October 1, 1958.

    Since that time, most U.S. space exploration efforts have been led by NASA, including the Apollo moon-landing missions, the Skylab space station, and later the Space Shuttle. Currently, NASA is supporting the International Space Station and is overseeing the development of the Orion Multi-Purpose Crew Vehicle and Commercial Crew vehicles. The agency is also responsible for the Launch Services Program (LSP) which provides oversight of launch operations and countdown management for unmanned NASA launches. Most recently, NASA announced a new Space Launch System that it said would take the agency’s astronauts farther into space than ever before and lay the cornerstone for future human space exploration efforts by the U.S.

    NASA science is focused on better understanding Earth through the Earth Observing System, advancing heliophysics through the efforts of the Science Mission Directorate’s Heliophysics Research Program, exploring bodies throughout the Solar System with advanced robotic missions such as New Horizons, and researching astrophysics topics, such as the Big Bang, through the Great Observatories [Hubble, Chandra, Spitzer, and associated programs. NASA shares data with various national and international organizations such as from the [JAXA]Greenhouse Gases Observing Satellite.

     
  • richardmitnick 9:41 am on May 14, 2015 Permalink | Reply
    Tags: Arizona Daily Star, , , , NASA SDO   

    From Arizona Daily Star via AURA: “Local astronomers watch our dangerous sun” 

    AURA Icon
    Association of Universities for Research in Astronomy

    Temp 1

    1
    A coronal mass ejection, associated with a solar flare, blew out from just around the edge of the sun on May 1, 2013. Solar Dynamics Observatory [SDO] spacecraft, NASA

    NASA Solar Dynamics Observatory
    SDO

    April 25, 2015
    Dan Desrochers

    Matt Penn is, in some ways, a solar weatherman.

    Penn, an associate astronomer with the National Solar Observatory in Tucson, researches and observes sunspots and solar flares. Part of his work involves predicting when a flare might occur.

    “We have this overall rough picture,” Penn said. “Sort of like meteorologists had before the Space Age.”

    Penn’s challenge is to increase the ability to tell when a solar flare will happen and who will be affected, kind of like how meteorologists can predict when and where a hurricane will hit. He’s trying to do this through studying changes in the sun’s magnetic field and looking at the patterns of flares to determine when one might happen.

    “What we’d like to say is at 11:15 we’re going to have a flare, and it’s going to have a CME (coronal mass ejection) of a certain size,” Penn said. “We can’t do that yet.”

    That ability to predict solar events is important. In March, NASA space weather scientists warned that a coronal mass ejection could cause communication disruptions, along with auroras, as far south as Oklahoma.

    The geomagnetic storm caused by this particular CME was weaker than predicted, but warning is critical. A direct hit from a large coronal mass ejection could cripple communication and power systems.

    A solar flare contains two parts. The first, the solar flare itself, is a brightening where the flare emits X-rays and gamma rays. Those are just a form of electromagnetic radiation, and while they can affect people and objects in space, they don’t affect us on Earth because the atmosphere protects us.

    The solar flare is followed, in 90 percent of cases, by a coronal mass ejection. That’s where things on Earth can get weird.

    “Imagine like a slinky, and both ends of the slinky are rooted in the sun,” said Joe Giacalone, an astrophysicist and the assistant head of the University of Arizona’s Department of Planetary Sciences, “Then the thing continually expands out.”

    The coronal mass ejection is a bunch of magnetized plasma — shot out from the sun.

    “You need to have the material, the magnetic field and the plasma of the sun work its way out at high speeds and smash into the Earth,” Giacalone said. “That’s the coronal mass ejection that does that.”

    When that mass hits the Earth, the Earth’s magnetic field gets shaken a little bit. That can cause beautiful images, like the Aurora Borealis, but it can also cause damage to transformers, GPS systems and communication devices. It can cause problems for banks, electric companies and TV providers. And all this can cost companies money.

    “A chunk of the sun is coming off,” Giacalone said. “A big piece of mass is coming off the sun and entrained in the magnetic field.”

    In 1859, one of the biggest and most famous flares caused the Carrington event, where a coronal mass ejection caused huge currents in telegraph lines and fires in telegraph offices.

    More recently, a geomagnetic storm caused widespread, nine-hour blackouts in Quebec in 1989, when currents generated by a coronal mass ejection blew the circuits on the local power grid.

    “Anytime you vary the magnetic field of the Earth — those variations can produce currents, and currents that primarily run through the ground,” Giacalone said.

    The North American Electric Reliability Corp., an international regulatory agency, sets procedures for monitoring and responding to geomagnetic storms.

    Locally, utility companies such as Tucson Electric Power Co. are more focused on power outages from Earth-based weather. TEP has a variety of methods to get its equipment up and running, spokesman Joseph Barrios said.

    “Of all the things that affect our system and reliability and the service we provide to customers,” Barrios said, “solar flares aren’t at the top of our list.”

    Solar flares can occur anytime but are more likely to occur when the sun is at the maximum range of its 11-year cycle of activity, as it is now.

    This particular “solar max,” however, has been particularly mild, Penn said.

    “It’s about half the strength in terms of the number of sun spots as the last cycle,” Penn said.

    See the full article here.

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  • richardmitnick 3:01 pm on March 11, 2015 Permalink | Reply
    Tags: , , NASA SDO,   

    From NASA Goddard: “Sun Emits Significant Solar Flare” 

    NASA Goddard Banner
    NASA Goddard Space Flight Center

    March 11, 2015
    Karen C. Fox
    NASA’s Goddard Space Flight Center, Greenbelt, Maryland

    1
    NASA’s Solar Dynamics Observatory captured an image of a mid-level solar flare on March 11, 2015, seen as a bright flash of light on the left side of the sun. Earth is shown for scale.
    Image Credit: NASA/SDO

    NASA Solar Dynamics Observatory
    SDO

    The sun emitted a significant solar flare, peaking at 12:22 p.m. EDT on March 11, 2015. NASA’s Solar Dynamics Observatory, which watches the sun constantly, captured an image of the event. Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth’s atmosphere to physically affect humans on the ground, however — when intense enough — they can disturb the atmosphere in the layer where GPS and communications signals travel.

    To see how this event may affect Earth, please visit NOAA’s Space Weather Prediction Center at http://spaceweather.gov, the U.S. government’s official source for space weather forecasts, alerts, watches and warnings.

    This flare is classified as an X2.2-class flare. X-class denotes the most intense flares, while the number provides more information about its strength. An X2 is twice as intense as an X1, an X3 is three times as intense, etc.

    Updates will be provided as needed.

    What is a solar flare?

    For answers to this and other space weather questions, please visit the Spaceweather Frequently Asked Questions page.

    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 6:08 am on February 15, 2015 Permalink | Reply
    Tags: , , NASA SDO   

    From NASA Goddard: “Stunning Video of the Sun” 

    NASA Goddard Banner

    To mark the fifth anniversary of the Solar Dynamics Observatory, NASA released some amazing footage its collected.

    NASA SDO
    NASA SDO schematic
    SDO

    Watch, enjoy, learn.

    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

     
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