Friday, March 9, 2012

NOAA Spaceweather Detects Another Solar Flare Headed To Earth

CAPE CANAVERAL, Florida --NOAA's National Weather Service Space Prediction Center detected another solar flare last night at 10:53 EST on March 8 with another Coronal Mass Ejection on its way to earth.  The Space Weather Prediction center's bulletin follows:

2012-03-09 12:36 UTC  Solar Activity Continues, Another CME On Its Way
The coronal mass ejection (CME) associated with the R3 (Strong) Radio Blackout event from 0024 UTC March 7 (7:24 p.m. EST March 6) continues to affect the Earth and G3 (Strong) storming levels have now been observed.  The magnetic field orientation needed to cause strong geomagnetic storming finally occurred overnight, so although it got off to a slow start, levels have reached what was predicted.  Solar Radiation Storm levels remain at S2 (Moderate) levels, flattening out in response to a new, R2 (Moderate) solar flare occurring at 0353 UTC March 9 (10:53 p.m. EST March 8).  This R2 event had an associated coronal mass ejection and analysis is pending to determine the expected arrival time and resulting geomagnetic storm intensity.

Yesterday, NASA released its most recent update regarding the massive solar flares that erupted on March 6:

NASA UPDATE: "The leading edge of the March 6 coronal mass ejection (CME), reached NASA's Advanced Composition Explorer (ACE) satellite at 5:42 AM EST. ACE sits just outside of Earth's magnetic environment, the magnetosphere. As magnetic fields from the CMEs connected up to the magnetosphere, instruments on Earth began to measure changes in our planet's magnetic fields – indicating the onset of a geomagnetic storm. At the time of writing this was still a minor storm, rated a G1 on a scale of G1 to G5. There will be updates as needed if the rating increases."

The sun erupted with one of the largest solar flares of this solar cycle on March 6, 2012 at 7PM ET. This flare was categorized as an X5.4, making it the second largest flare -- after an X6.9 on August 9, 2011 -- since the sun’s activity segued into a period of relatively low activity called solar minimum in early 2007. The current increase in the number of X-class flares is part of the sun’s normal 11-year solar cycle, during which activity on the sun ramps up to solar maximum, which is expected to peak in late 2013.

About an hour later, at 8:14 PM ET, March 6, the same region let loose an X1.3 class flare. An X1 is 5 times smaller than an X5 flare.

These X-class flares erupted from an active region named AR 1429 that rotated into view on March 2. Prior to this, the region had already produced numerous M-class and one X-class flare. The region continues to rotate across the front of the sun, so the March 6 flare was more Earthward facing than the previous ones. It triggered a temporary radio blackout on the sunlit side of Earth that interfered with radio navigation and short wave radio.

In association with these flares, the sun also expelled two significant coronal mass ejections (CMEs), which are travelling faster than 600 miles a second and may arrive at Earth in the next few days. In the meantime, the CME associated with the X-class flare from March 4 has dumped solar particles and magnetic fields into Earth’s atmosphere and distorted Earth's magnetic fields, causing a moderate geomagnetic storm, rated a G2 on a scale from G1 to G5. Such storms happen when the magnetic fields around Earth rapidly change strength and shape. A moderate storm usually causes aurora and may interfere with high frequency radio transmission near the poles. This storm is already dwindling, but the Earth may experience another enhancement if the most recent CMEs are directed toward and impact Earth.

In addition, last night’s flares have sent solar particles into Earth’s atmosphere, producing a moderate solar energetic particle event, also called a solar radiation storm. These particles have been detected by NASA’s SOHO and STEREO spacecraft, and NOAA’s GOES spacecraft. At the time of writing, this storm is rated an S3 on a scale that goes up to S5. Such storms can interfere with high frequency radio communication.

Besides the August 2011 X-class flare, the last time the sun sent out flares of this magnitude was in 2006. There was an X6.5 on December 6, 2006 and an X9.0 on December 5, 2006. Like the most recent events, those two flares erupted from the same region on the sun, which is a common occurrence.