Solar and Aurora Activity Chat

[Polar Maritime]

[Polar Maritime]

[karyo]

Solar activity is low once again and the solar flux at 106.

Quiet times!

Karyo

[Polar Maritime]

[Polar Maritime]

[Polar Maritime]

CORONAL HOLE: Spewing solar wind, a yawning dark fissure in the sun's atmosphere is turning toward Earth. NASA's Solar Dynamics Observatory photographed the "coronal hole" during the early hours of June 1st:

Coronal holes are places where the sun's magnetic field opens up and allows the solar wind to escape. A stream of solar wind flowing from this coronal hole will reach Earth on June 5th - 7th, possibly stirring geomagnetic storms. High-latitude sky watchers should be alert for aurora. Spaceweather.com

Edited June 2, 2012 by Polar Maritime

[Polar Maritime]

http://www.youtube.com/watch?v=l8myUZsxfCs

[Polar Maritime]

SOLAR TSUNAMI: New sunspot 1496 unleashed an impulsive M3-class solar flare on June 3rd at 1755 UT. In New Mexico, amateur astronomer Thomas Ashcraft was monitoring the sun when the explosion occurred, and he video-recorded a powerfulsolar tsunami issuing from the blast site:

"This was a great solar event!" says Ashcraft. "The blast wave sparked powerful radio emissions as it plowed through the sun's atmosphere, and I recorded the sounds using my shortwave radio telescope."

The explosion also hurled a coronal mass ejection (CME) into space: SOHO movie. The cloud does not appear to be heading for Earth, although this conclusion could be revised by further analysis. spaceweather.com

Edited June 4, 2012 by Polar Maritime

[Polar Maritime]

[Polar Maritime]

[Polar Maritime]

[Polar Maritime]

[Polar Maritime]

[Polar Maritime]

M-FLARES: A fast-growing active region near AR1499 is crackling with impulsive M-class solar flares, including two on June 9th (1132 UT and 1650 UT). This development could signal an uptick in solar activity. Solar flare alerts: text, voice.

In Falmouth, Maine, amateur astronomer John Stetson photographed the ongoing activity around sunspot AR1499:

"These solar active regions are producing M-class and C-class flares that are easy to see through my H-alpha telescope," says Stetson.

NOAA forecasters estimate a 25% chance of more M-class flare today, although this is probably an underestimate considering the rapid pace of development of magnetic fields near AR1499. Spaceweather.com

[Polar Maritime]

[Polar Maritime]

[Polar Maritime]

MILD GEOMAGNETIC STORM: A mild (Kp=5) geomagnetic storm is in progress, sparking high-latitude auroras. Barth Firth sends this picture from Dawsonville, New Brunswick:

"The auroras lasted just a couple of minutes, [but they were beautiful]," says Firth. "They were blue to purple in color."

The storm was sparked by an episode of "negative IMF." That is, south-pointing magnetic fields in the solar wind opened a crack in Earth's magnetosphere; solar wind poured in and fueled the display. NOAA forecasters estimate a 10% to 20% chance of similar storms in the next 24 hours as the solar wind continues to blow.Magnetic storm alerts: text, voice.

more images: from Christopher Gregg of Mount Washington Observatory, New Hampshire; from Gilles Boutin of St-Michel Québec Canada; from Guillaume Poulinof Cookshire, Québec, Canada. spaceweather.com

[Polar Maritime]

[Polar Maritime]

[Polar Maritime]

During a powerful solar blast in March, NASA's Fermi Gamma-ray Space Telescope detected the highest-energy light ever associated with an eruption on the sun. The discovery heralds Fermi's new role as a solar observatory, a powerful new tool for understanding solar outbursts during the sun's maximum period of activity.

"For most of Fermi's four years in orbit, its Large Area Telescope (LAT) saw the sun as a faint, steady gamma-ray source thanks to the impacts of high-speed particles called cosmic rays," said Nicola Omodei, an astrophysicist at Stanford University in California. "Now we're beginning to see what the sun itself can do."

A solar flare is an explosive blast of light and charged particles. The powerful March 7 flare, which earned a classification of X5.4 based on the peak intensity of its X-rays, is the strongest eruption so far observed by Fermi's LAT. The flare produced such an outpouring of gamma rays -- a form of light with even greater energy than X-rays -- that the sun briefly became the brightest object in the gamma-ray sky.

At the flare's peak, the LAT detected gamma rays with two billion times the energy of visible light, or about 4 billion electron volts (GeV), easily setting a record for the highest-energy light ever detected during or just after a solar flare. The flux of high-energy gamma rays, defined as those with energies beyond 100 million electron volts (MeV), was 1,000 times greater than the sun's steady output.

The March 7 flare also is notable for the persistence of its gamma-ray emission. Fermi's LAT detected high-energy gamma rays for about 20 hours, two and a half times longer than any event on record.

Additionally, the event marks the first time a greater-than-100-MeV gamma-ray source has been localized to the sun's disk, thanks to the LAT's keen angular resolution.

Flares and other eruptive solar events produce gamma rays by accelerating charged particles, which then collide with matter in the sun's atmosphere and visible surface. For instance, interactions among protons result in short-lived subatomic particles called pions, which produce high-energy gamma rays when they decay. Nuclei excited by collisions with lower-energy ions give off characteristic gamma rays as they settle down. Accelerated electrons emit gamma rays as they collide with protons and atomic nuclei.

Solar eruptions are now on the rise as the sun progresses toward the peak of its roughly 11-year-long activity cycle, now expected in mid-2013.

[Polar Maritime]

CHANCE OF FLARES: NOAA forcasters estimate a 40% chance of M-class solar flares today as a phalanx of sunspots turns toward Earth. The most likely source of geoeffective eruptions is sunspot AR1504, which has grown into an active region almost 10 times wider than Earth. Solar flare alerts: text, voice.

As predicted, the sunspot has flared. Magnetic fields above AR1504 erupted on June 13th at 1319 UT, producing a long-duration M1-class solar flare. NASA's Solar Dynamics Observatory recorded the extreme UV glow of the blast:

The ongoing explosion is taking hours to unfold, which means it is very powerful despite its middling M1-peak. Long duration flares often hurl coronal mass ejections (CMEs) into space, and this one is probably no exception. Stay tuned for updates about a possible Earth-directed CME. spaceweather.com

[Polar Maritime]

http-~~-//www.youtube.com/watch?v=xBOKJRgmwS4&list=UUIp0KTgnQNZJIOQZqrVDw1g&index=1&feature=plcp

CME TARGETS VENUS, EARTH MARS: Active sunspot AR1504 erupted on June 13th at 1319 UT, producing a long-duration M1-flare and hurling a CME into space. According to analysts at the Goddard Space Weather Lab, the cloud will deliver a glancing blow to three planets: Venus on June 15th, Earth on June 16th, and Mars on June 19th. This animation shows the likely progression of the cloud:

NOAA forecasters estimate a 25% - 30% chance of geomagnetic storms when the cloud reaches Earth. High-latitude sky watchers should be alert for auroras. Spaceweather.com

Edited June 14, 2012 by Polar Maritime

[Polar Maritime]

[Polar Maritime]

[Polar Maritime]

New Solar Active Region Spitting Out Flares

06.14.12

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This movie from the Solar Dynamics Observatory (SDO) shows the M class flare on June 14, 2012 from 9:15 AM to 2:00 PM EDT. The sun is shown here in teal as this is the color typically used to represent light in the 131 Angstrom wavelength, a wavelength particularly good for observing flares. Credit: NASA/SDO

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Active Region 1504 has been active since rotating into view. Credit: SDO/HMI

An active region on the sun, numbered AR 1504, rotated into view over the left side of the sun on June 10, 2012. The region fired off two M-class flares and two coronal mass ejections (CMEs) on June 13 and June 14, 2012. The first flare lasted for a relatively long three hours, peaking on June 13, 2012 at 9:17 AM EDT. The associated CME traveled at approximately 375 miles per second and is directed toward Earth, though due to its slow speed, the effect on Earth is expected to be minimal.

The second M-class flare was also a long-duration flare, and it peaked on June 14, 2012 at 10:08 AM EDT. The CME associated with this flare is traveling much faster – preliminary analysis at Goddard's Space Weather Center indicates it is traveling at speeds of approximately 800 miles per second. It is traveling toward Earth, and could also impact Mars and the Spitzer spacecraft.

The Space Weather Center models estimate that both CMEs will arrive on June 16.

We will provide updates if AR1504 generates additional space weather.

The Solar Dynamics Observatory captured this image of an M1.2 class flare on June 13, 2012. The sun is shown here in teal as this is the color typically used to represent light in the 131 Angstrom wavelength, a wavelength particularly good for observing flares. Credit: NASA/SDO