Solar Storms Possible

CHANCE OF STORMS: NOAA forecastesrs estimate a 65% chance of polar geomagnetic storms on August 10th when one and perhaps two CMEs are expected to hit Earth’s magnetic field. The incoming clouds were propelled from the sun by a flurry of erupting magnetic filaments on Aug. 6-7. High-latitude sky watchers should be alert for auroras.

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Large Sunspot Eruptions

BIG SUNSPOT FACES EARTH: Colossal sunspot AR1785 is now directly facing Earth. The active region has a ‘beta-gamma-delta’ magnetic field that harbors energy for X-class flares, yet so far the sunspot has been mostly quiet. Could it be the calm before the storm? NOAA forecasters estimate a 55% chance of M-flares and a 10% chance of X-flares on July 8th.

Sprawling more than 11 Earth-diameters from end to end, AR1785 is one of the biggest sunspots of the current solar cycle. In fact, it can barely fit on the screen. Click on the dark core below to see a complete hi-res picture taken by Christian Viladrich of Nattages, France:

To take the picture, Viladrich used a filtered 14-inch Celestron telescope. All those irregular blobs surrounding the primary dark core are boiling granules of plasma as small as the state of California or Texas. It’s a very sharp picture.

from: spaceweather.com

New Impressive Solar Flare 6/24

M-CLASS SOLAR FLARE: Sunspot AR1778 produced an impulsive M2-class solar flare on June 23rd at 20:56 UT. NASA’s Solar Dynamics Observatory recorded the extreme ultraviolet flash:

The eruption flung material away from the blast site, but the debris does not appear to be heading toward Earth. Except for the effects of the UV flash, which created a short-lived wave of ionization in Earth’s upper atmosphere, this flare was not geo-effective.

More flares could be in the offing. In addition to AR1778, sunspots AR1775 and AR1776 have ‘beta-gamma’ magnetic fields that harbor energy for significant eruptions. NOAA forecasters estimate a 40% chance of M-flares and a 5% chance of X-flares on June 24th.

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Solar Flare

SOLSTICE SOLAR FLARE: This morning, June 21st at 03:16 UT, the sun itself marked the solstice with an M2-class solar flare from sunspot AR1777. NASA’s Solar Dynamics Observatory photographed the extreme ultraviolet flash and a plume of material flying out of the blast site:

As sunspots go, AR1777 is neither large nor apparently menacing, yet it has been crackling with flares for days. Before it rotated over the sun’s eastern limb on June 20th, it unleashed a series of farside flares and CMEs. Today’s explosion was not Earth directed, but future explosions could be as the sun’s rotation continues to turn AR1777 toward our planet. NOAA forecasters estimate a 30% chance of M-flares and a 5% chance of X-flares during the next 24 hours.

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Solar FIlaments

AN OUTBREAK OF MAGNETIC FILAMENTS: The sunspot number may be low, but the sun is far from blank. Amateur astronomers monitoring the sun report a large number of magnetic filaments snaking across the solar disk. Sergio Castillo captured more than half a dozen in this picture he sends from his backyard observatory in Inglewood, California:

“Filaments are popping up all over the solar surface,” says Castillo. “Each one has a unique shape and length.”

The longest one, in the sun’s southern hemisphere stretches, more than 400,000 km from end to end. “It’s one of the longest filamentary structures I have ever seen,” says veteran observer Bob Runyan of Shelton, Nebraska.

If any of the filaments collapses, it could hit the stellar surface and explode, producing a Hyder flare. Filaments can also become unstable and erupt outward, hurling pieces of themselves into space. Either way, astronomers with solar telescopes are encouraged to monitor developments.

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Geomagnetic Storm

GEOMAGNETIC STORM: A G1-class (Kp=5) geomagnetic storm is in progress following the arrival of an interplanetary shock wave on May 31st. The source of the shock is not known; it might have been a minor CME that left the sun without drawing attention to itself. The impact sparked auroras across many northern-tier US states. This photo, for instance, comes from Christopher Griffith in Baxter, Minnesota:

“I wasn’t expecting to see any lights, but right before the midnight it broke loose and the sky lit up,” says Griffith. “Sadly the clouds quickly filled in my little window, and the auroras were gone. Just thankful for what I got so see!” Elsewhere in the USA, auroras were sighted as far south as Colorado, Maryland, Iowa, Wisconsin, and Nebraska.

High-latitude sky watchers should remain alert for auroras tonight as Earth’s magnetic field continues to reverberate from the impact. NOAA forecasters estimate a 40% chance of polar geomagnetic storms on June 1st.

from:   spaceweather.com

New CME 5/22

M5-CLASS EXPLOSION: The ongoing radiation storm got started on May 22nd when the magnetic canopy of sunspot AR1745 exploded. The blast produced an M5-class solar flare and hurled a magnificent CME over the sun’s western limb:


Credit: the Solar and Heliospheric Observatory (SOHO)

The movie of the CME is very “snowy.” That is caused by high-energy solar protons striking the CCD camera in SOHO’s coronagraph. Each strike produces a brief snow-like speckle in the image. This hailstorm of solar protons is what forecasters mean by “radiation storm.”

Although the explosion was not squarely Earth-directed, the CME will likely be geoeffective. The expanding cloud appears set to deliver a glancing blow to Earth’s magnetic field on May 24th around 1200 UT. According to NOAA forecast models, the impact will more than double the solar wind plasma density around Earth and boost the solar wind speed to ~600 km/s.

from:    spaceweather.com

Incoming CME

ANOTHER INCOMING CME: As Earth’s magnetic field reverberates from one CME strike, a second more potent CME is on the way. It was propelled in our direction by sunspot AR1748, which unleashed an M3-class solar flare on May 17th (0858 UT). Although this is not the strongest flare we’ve seen from AR1748, it could be the most geoeffective; the sunspot was almost-squarely facing Earth when the blast occurred. NOAA forecasters estimate a 75% chance of polar geomagnetic storms when the cloud arrives.

The Solar and Heliospheric Observatory took this picture of the CME leaving the sun at 1500 km/s (3.4 million mph) on May 17th:

In the video, the CME appears to hit Mercury, but it does not. It is merely passing in front of the innermost planet. The planet in the line of fire is actually Earth.

from:    spaceweather.com

On Magnetic Fields & Shells

Magnetic shell provides unprecedented control of magnetic fields January 4, 2013 by Lisa Zyga feature
 The newly designed magnetic shell can either expel or concentrate magnetic energy.
A general property of magnetic fields is that they decay with the distance from their magnetic source. But in a new study, physicists have shown that surrounding a magnetic source with a magnetic shell can enhance the magnetic field as it moves away from the source, allowing magnetic energy to be transferred to a distant location through empty space. By reversing this technique, the scientists showed that the transferred magnetic energy can be captured by a second magnetic shell located some distance away from the first shell. The second shell can then concentrate the captured magnetic energy into a small interior region. The achievement represents an unprecedented ability to transport and concentrate magnetic energy, and could have applications in the wireless transmission of energy, medical techniques, and other areas.
The physicists, Carles Navau, Jordi Prat-Camps, and Alvaro Sanchez at the Autonomous University of Barcelona in Spain, have published their results on their new method of magnetic energy distribution and concentration in a recent issue of Physical Review Letters. “We have tried with this work to open new ways of shaping magnetic fields in space,” Sanchez told Phys.org. “Since magnetic fields are so crucial for so many technologies (e.g., almost 100% of the energy generated uses magnetic fields), finding these new possibilities may bring benefits.” The basis of the technique lies in transformation optics, a field that deals with the control of electromagnetic waves and involves metamaterials and invisibility cloaks. While researchers have usually focused on using transformation optics ideas to control light, here the researchers applied the same ideas to control magnetic fields by designing a magnetic shell with specific electromagnetic properties. The shell can be used to control magnetic fields in two ways, depending on its location relative to a magnetic source. When a magnetic source is placed inside the shell, the shell expels the magnetic energy outside. When the shell is placed near a magnetic source located outside the shell, the shell harvests and concentrates the magnetic energy from the source into a hole in the shell’s center. Magnetic shell provides unprecedented control of magnetic fields Enlarge
Magnetic shells can be used to increase the magnetic energy of multiple magnets: The four magnetic dipoles in (a) interact very weakly, even when they are moved closer together in (b). However, when all four dipoles are surrounded by a shell as in (c), their exterior fields become enhanced, yielding a stronger magnetic field in the center region. Credit: Carles Navau, et al. ©2012 American Physical Society
In both cases, the shell works by dividing the space into an exterior and interior zone and then transferring the magnetic energy completely into one domain or the other. This method differs from the way that superconductors and ferromagnets distribute magnetic energy, where the energy always returns to the domain where the magnetic sources are. Although no material exists that can perfectly meet the requirements for the magnetic shell’s properties, the physicists showed that they could closely approximate these properties by using wedges of alternating superconducting and ferromagnetic materials.
For practical purposes, this approximation is sufficient to work for a variety of potential applications, in which the magnetic shell’s two functions (transferring and concentrating) can be used together or independently. For instance, by surrounding two magnetic dipoles with their own shells, the magnetic coupling between them can be enhanced, which could be used to improve the efficiency of wireless power transmission between a source and a receiver. With its ability to concentrate nearby magnetic fields, a single magnetic shell could also be used to increase the sensitivity of magnetic sensors. The scientists demonstrated that a magnetic sensor placed inside the shell can detect a much larger magnetic flux from an external magnetic source than it would when using a typical concentration strategy involving superconductors. Magnetic sensors are often used in consumer electronics, factory automation, navigation, and many other areas. The magnetic shell could also have medical applications, such as for biosensors that measure the brain’s response in magnetoencephalography, a technique used for mapping brain activity. The physicists also showed that the shells can be used to surround multiple magnetic sources arranged in a circle, allowing them to concentrate magnetic energy in the center of the circle. This arrangement could be used in transcranial magnetic stimulation (TMS), a technique used to treat psychiatric disorders. While TMS generally targets regions near the brain’s surface, the magnetic shells could help extend the reach of magnetic fields to deeper targets. Magnetic energy also plays a vital role in power applications, such as in power plants, magnetic memories, and motors. All of these applications require magnetic energy to be spatially distributed or concentrated in a certain way. By enabling the control of magnetic energy in new ways, the magnetic shells could improve these applications and others due to their many possible configurations. “We are presently working on extending these ideas of applying transformation optics to the magnetic case into different directions, and see how future designs can be implemented in practice (in the present case, we suggested superconductors and ferromagnetic materials as a practical implementation of the magnetic shell),” Sanchez said. More information: Carles Navau, et al. “Magnetic Energy Harvesting and Concentration at a Distance by Transformation Optics.” PRL 109, 263903 (2012). DOI: 10.1103/PhysRevLett.109.263903

Read more & get images at: http://phys.org/news/2013-01-magnetic-shell-unprecedented-fields.html#jCp