Zonnevlammen #2: Recht op aarde af

SOLAR FLARE X2 CLASS MOST POWERFUL CMA IN FOUR YEARS IT WILL HIT EARTH IN 48HRS FEB 15 2011.mov

quote:

Sterrenwacht waarschuwt voor "extreem ruimteweer"

Bij de Koninklijke Sterrenwacht (KSB) zijn afgelopen nacht de automatische alarmsystemen in werking getreden: op de Zon is een extreme zonnevlam waargenomen. Dat meldt de KSB, die waarschuwt voor een mogelijke impact voor onze planeet. De vorige zonnevlam van die grootte dateert van december 2006. Sommigen opperden in 2009 zelfs dat de Zon zogenaamd "dood" zou zijn. Maar niets is minder waar, aldus de KSB. Volgens de gespecialiseerde website spaceweater.com deed zich de eerste zogenaamde "x-flare" voor van de nieuwe zonnecyclus (die 11 jaar duurt), de 24ste cyclus. De piek was om 02.56 uur Belgische tijd.



De KSB waarschuwt op basis van satellietgegevens, onder andere van de Belgische Proba-2 satelliet, dat een plasmawolk zich richting Aarde voortbeweegt met een vermoedelijke snelheid van 1.000 km/s. Die wolk zal de Aarde donderdag treffen. Een satelliet die zich vlak voor de Aarde in het zicht van de Zon bevindt heeft ook reeds een stroom van energetische deeltjes waargenomen. Voorlopig is het stormniveau niet bereikt, voegt de KSB eraan toe.

Noorderlicht
Het ruimteweerteam moet nu in de eerste plaats de magnetische structuur van de wolk proberen te achterhalen. Die bepaalt hoe het magnetisch schild van de Aarde op de impact zal reageren. Als een aantal voorwaarden zijn voldaan, kunnen we misschien donderdag het noorderlicht waarnemen, zegt de Sterrenwacht. Extreem ruimteweer kan satellieten doen uitvallen en kan gevolgen hebben voor de stroomvoorziening op Aarde.

quote:

Monsterflare heading for earth
The sun unleashed its strongest solar flare in four years last night (Feb. 14), hurling a massive wave of charged particles from electrified gas into space and toward Earth.

The solar storm sent a flash of radiation that hit Earth in a matter of minutes. Now a huge cloud of charged particles is headed our way. These coronal mass ejections, as they are called, typically take around 24 hours or more to arrive. They can spark spectacular displays of the aurora borealis, or Northern Lights, at high latitudes and sometimes even into the northern United States.

The mega flare, which registered as a Class X2.2 flare on the scale of solar flares, was the first class X flare to occur in the new solar cycle of activity, which began last year. The sun is now ramping up toward a solar maximum around 2013.

"It has been the largest flare since Dec 6, 2006, so a long time coming," said Phil Chamberlin, deputy project scientistfor NASA's Solar Dynamics Observatory, which observed the flare. "There were some clues that led us to believe the likelihood of moderate to large flares (M class or above) could occur, but we were all surprised when it actually happened to be a large X-class."

Class X flares are the strongest types of solar flares that can erupt from the sun. There are also two weaker categories: Class M flares, which are medium strength but still powerful, and Class C flares, which are the weakest storms from the sun.

Last night's X2.2 flare is the most powerful solar eruption of the sun's current weather cycle, called Solar Cycle 24. According to the website Spaceweather.com, which monitors space weather and skywatching events, the flare was the strongest of the last four years.

"It just means that Solar Cycle 24 is ramping up!" Chamberlin told SPACE.com. "This is the first of probably many more X-class flare to occur over the next 2 to 4 years as we reach the peak and then descend back down from solar cycle 24 maximum."

The Monday flare came on the heels of another, only slightly less powerful, class M6.6 flare on Sunday, Feb. 13. Both events erupted from the same area on the sun, called active region 1158

"AR 1158 is in the southern hemisphere, which has been lagging the north in activity but now leads in big flares!" NASA scientists wrote on the Solar Dynamics Observatory website.

Yesterday's Class X flare erupted at 8:50 p.m. EST on Feb.14 (0150 GMT Feb. 15).

Such a flare can bathe the Earth in high doses of ultraviolet radiation and X-rays hurl a huge burst of solar wind in our direction. When this burst arrives at Earth, the electrons and protons from the solar wind come into contact with our planet's magnetic field, and stream toward the magnetic poles.

The disturbance can create a geomagnetic storm in Earth's magnetic field.

"Geomagnetic storms are possible when the CME arrives 36 to 48 hours hence," Spaceweather.com reported.

quote:

Plasmawolk bereikt aarde
De plasmawolk die maandag de zon heeft verlaten, heeft vrijdagmorgen de aarde bereikt. De 'coronal mass ejection' botste omstreeks 02.00 uur Belgische tijd met het magnetisch veld van de aarde. De impact was niet zo hevig als enkele dagen eerder werd verwacht.

Donderdag had de Koninklijke Belgische Sterrenwacht al laten weten dat de plasmawolk hoogstwaarschijnlijk was vertraagd door de zonnewind en door twee voorafgaande minder snelle plasmawolken.

De wolk heeft hierdoor een deel van zijn energie verloren, wat verklaart dat de impact minder energetisch was. De voorspelling luidde dat er in België geen poollicht te zien zou zijn.
Zonnemassa

Een plasmawolk is een grote hoeveelheid zonnemassa die wordt weggekatapulteerd. Zo'n wolk bereikt meestal na twee tot vijf dagen onze planeet als ze onze richting uitvliegt. Een plasmawolk kan een magnetische storm veroorzaken.

Radiocommunicatie wordt bemoeilijkt of kan wegvallen, navigatiesystemen ondervinden nadeel, elektrische stromen kunnen geīnduceerd worden in elektriciteits- en pijpleidingen. Bij magnetische stormen is de breedtegraad belangrijk. Of het dag of nacht is, maakt niet uit.

Het magnetisch veld van de aarde beschermt ons tegen de impact van plasmawolken.

quote:

Scientists warn for solar 'Katrina'
The sun is waking up from a long quiet spell. Last week it sent out the strongest flare for four years – and scientists are warning that earth should prepare for an intense electromagnetic storm that, in the worst case, could be a “global Katrina” costing the world economy $2,000bn.

Senior officials responsible for policy on solar storms – also known as space weather – in the US, UK and Sweden urged more preparedness at the annual meeting of the American Association for the Advancement of Science in Washington.
“We have to take the issue of space weather seriously,” said Sir John Beddington, UK chief scientist. “The sun is coming out of a quiet period, and our vulnerability has increased since the last solar maximum [around 2000].”

“Predict and prepare should be the watchwords,” agreed Jane Lubchenco, head of the US National Oceanic and Atmospheric Administration. “So much more of our technology is vulnerable than it was 10 years ago.”

A solar storm starts with an eruption of super-hot gas travelling out from the sun at speeds of up to 5m miles an hour. Electrically charged particles hit earth’s atmosphere 20 to 30 hours later, causing electromagnetic havoc.

quote:

APPROACHING ACTIVE REGION: A significant active region is about to emerge over the sun's northeastern limb. The underlying sunspots are not yet visible from Earth, but the region's towering magnetic canopy is already in view. NASA's Solar Dynamics Observatory (SDO) took this picture during the early hours of Feb. 23rd:

A better view is had by NASA's STEREO-B probe, stationed over the sun's eastern limb where it can see the region from top down. Recent movies beamed back by STEREO-B show flashes of extreme UV radiation and hints of magnetic instability. This could herald a period of renewed solar activity when the region turns toward Earth in the days ahead. Or the action could peter out beforehand. Stay tuned for updates.
Bron: Spaceweather.com

quote:

The quiet didn't last long. Earth-orbiting satellites detected an M3-class solar flare at 0735 UT on Feb. 24th. The source was an active region located just behind the sun's eastern limb. The eruption produced strong radio emissions, a coronal mass ejection (not Earth directed), and this spectacular picture taken by NASA's Solar Dynamics Observatory:

The active region responsible for this blast will emerge over the eastern limb during the next 24-48 hours, setting the stage for possible geoeffective solar activity. Stay tuned for updates.

quote:

Another X-flare heading for earth?
X-FLARE: March 9th ended with a powerful solar flare. Earth-orbiting satellites detected an X1.5-class explosion from behemoth sunspot 1166 around 2323 UT. A movie from NASA's Solar Dynamics Observatory shows a bright flash of UV radiation plus some material being hurled away from the blast site:

A first look at coronagraph images from NASA's STEREO-B spacecraft suggests that the explosion did propel a coronal mass ejection (CME) toward Earth. This conclusion is preliminary, however, so check back later for updates.

After four years without any X-flares, the sun has produced two of the powerful blasts in less than one month: Feb. 15th and March 9th. This continues the recent trend of increasing solar activity, and shows that Solar Cycle 24 is heating up. NOAA forecasters estimate a 5% chance of more X-flares during the next 24 hours