NASA SDO: Tracking a gigantic sunspot across the Sun

Super sunspot AR2192 produced 10 significant solar flare while traversing the Earth-side of the sun; six X-class and four above M5-class. 

Credit: NASA/SDO

An active region on the sun, an area of intense and complex magnetic fields, rotated into view on Oct. 18, 2014.

Labeled AR2192, it soon grew into the largest such region in 24 years, and fired off 10 sizable solar flares as it traversed across the face of the sun.

The region was so large it could be seen without a telescope for those looking at the sun with eclipse glasses, as many did during a partial eclipse of the sun on Oct. 23.

"Despite all the flares, this region did not produce any significant coronal mass ejections," said Alex Young a solar scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland."

"Coronal mass ejections, or CMEs, are giant clouds of solar particles that can affect technology when they reach near-Earth space."

"You certainly can have flares without CMEs and vice versa, but most big flares do have CMEs. So we're learning that a big active region doesn't always equal the biggest events."

The largest sunspot since November 1990 is seen traveling across the front of the sun in these images from NASA's SDO, captured Oct. 17-Oct 29, 2014. 

Credit: NASA/SDO

Such active regions are measured in millionths of a solar hemisphere, where 1 micro-hemisphere, or MH, is about 600,000 square miles.

This region topped out at 2,750 MH, making it the 33rd largest region out of approximately 32,000 active regions that have been tracked and measured since 1874.

It is the largest sunspot seen since AR 6368, which measured 3,080 MH on Nov. 18, 1990.

The largest five active regions ever observed were between 4,000 and more than 6,000 MH and they all appeared between 1946 and 1951.

On the other hand, the region that produced one of the biggest solar flares of all time on Sep. 1, 1859, in what's known as the Carrington event, wasn't even one of the top 50 at only 2,300 MH.

During its trip across the front of the sun, AR 12192 produced six X-class flares, which are the largest flares, and four strong M-class flares. M-class flares are one tenth as strong as 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.

"Having so many similar flares from the same active region will be a nice case study for people who work on predicting solar flares," said Dean Pesnell, project scientist for NASA's Solar Dynamics Observatory at Goddard.

"This is important for one day improving the nation's ability to forecast space weather and protect technology and astronauts in space."



This movie shows fireworks on the sun as 10 significant flares erupted on the sun from Oct. 19-28, 2014. 

The graph shows X-ray output from the sun as measured by NOAA’s GOES spacecraft. The X-rays peak in sync with each flare. 

Credit:  NASA/SDO/NOAA/GOES

AR 12192 rotated onto the far side of the sun on Oct. 30, 2014, however as it evolves, we may see a new version of it rotating back into view in two weeks.

NASA SDO: Extreme Solar Flare heading to Earth

The Sun by the Atmospheric Imaging Assembly of NASA's Solar Dynamics Observatory. 

Credit: NASA

Scientists say an extreme X-Class solar flare is blasting its way to Earth and could mess up some power grids, satellites and radio transmissions.

Forecasters at NOAA's Space Weather Prediction Center don't yet know when Wednesday's solar storm will arrive here and which part of the planet will be facing the sun and bear the brunt of the effects.

It could be as early as Thursday morning to a few days.

Prediction Center director Tom Berger said scientists will have a better idea after they get more satellite data.

The X-Class flare is considered extreme on forecasters' scale, but just barely. Flares like this cause geomagnetic storms which can knock some power grids offline temporarily.

They also can damage satellites and disrupt radio transmissions but they expand the colourful Aurora Borealis (northern lights).

NASA SDO: FOUR X-class flares in 48 hours

These pictures from NASA's Solar Dynamics Observatory show the three of the Four X-class flares that the sun emitted in under 48 hours. 

The images show light with a wavelength of 131 angstroms, which is particularly good for showing solar flares and is typically colorised in teal. 

Credit: NASA/SDO

On Tuesday, it released the biggest solar flare of 2013 so far, an intense burst associated with a huge eruption of particles.

Also on May 13, 2013 the sun emitted a third significant solar flare in under 24 hours, peaking at 9:11 p.m.

This flare is classified as an X3.2 flare. This is the strongest X-class flare of 2013 so far, surpassing in strength the two X-class flares that occurred earlier in the 24-hour period.

The flare was also associated with a coronal mass ejection (CME). The CME began at 9:30 p.m. EDT and was not Earth-directed.

Experimental NASA research models show that the CME left the sun at approximately 1,400 miles per second, which is particularly fast for a CME.

The models suggest that it will catch up to the two CMEs associated with the earlier flares.

The merged cloud of solar material will pass by the Spitzer spacecraft and may give a glancing blow to the STEREO-B and Epoxi spacecraft.

Their mission operators have been notified. If warranted, operators can put spacecraft into safe mode to protect the instruments from solar material.