PLAY BY PLAY • A Closer Look at the Story Behind This Week’s M-Class Solar Flare, S3 Solar Radiation Storm and G1 Geomagnetic Storm
(YELLOWKNIFE, NORTHWEST TERRITORIES) National Oceanic and Atmospheric Administration Forecasters believed the impact of an Earth-directed M-Class solar flare that launched from Sunspot 1402 on January 22 would be quick and intense, and they were right. Here’s a closer look at the sequence of events that led up to the latest outburst of space weather excitement:
January 15, 2012 • Sunspot 1402 Visible From Earth • Massive Sunspot 1402 is visible from Earth as it emerges over the eastern limb of the Sun. Over the next few days it will rotate across the Earthward side of the Sun. Along with 1402, nearby Sunspot 1401 (just south of 1402) is also visible and both are considered to be a risk for Earth if either produces a solar flare in the days ahead. As these sunspots rotated towards the centre of the solar disk they became increasingly active.
January 22, 2012 • M-Class Solar Flare Eruption • A significant M9-Class solar flare erupts from Sunspot 1402 at approximately 4 a.m. Universal Time (UT) on January 23, which is 9 p.m. Mountain Standard Time on January 22. The space weather gurus at the NOAA and elsewhere begin crunching data to determine how and when this event will affect the magnetic field that surrounds (and protects) Earth. Solar flares are categorized as B-Class, C-Class, M-Class, or X-Class, with X flares being the most intense. Flares in the B and C Class are small, and the consequences of these events are barely noticeable on Earth. Each class of flare has 9 subdivisions, so as an M9 event, this flare was only slightly less powerful than an X-Class flare and attracted much more attention than the M3.2 flare that exploded from the same sunspot on January 19.
COMMENTARY: Mixed Reports About Source of Earth-Directed CME Trigger Wave of Geomagnetic Confusion
SOURCE OF CONFUSION. Sunspot 1402 erupted on Thursday, January 19, 2012, however some websites reported this M-Class Flare originated from Sunspot 1401, causing confusion about when the Coronal Mass Ejection would be arriving at Earth. (YouTube Video: Special Thanks to Solarham.com / Solar Dynamics Observatory / EUV Variability Experiment / Solar-Terrestrial Relations Observatory)
By James Pugsley
Astronomy North—
(YELLOWKNIFE, NORTHWEST TERRITORIES) When the eruption of an M3.2-Class solar flare occurred on January 19, launching a Coronal Mass Ejection (CME) in Earth’s general direction, geomagnetic forecasters quickly began predicting the trajectory, intensity and size of the expanding cloud of plasma. It didn’t take long for analysts at spaceweather.com and the Goddard Space Weather Lab to declare that Earth was in the direct path of the CME, and that a significant geomagnetic storm would be imminent on Saturday, January 19…likely around 22:30 UT (midday in Canada), give or take a few hours. In the same article it was identified that the CME originated from sunspot 1401.
Much like the solar flare itself, this story erupted. Mainstream and social media came alive with warnings and alerts, and why shouldn’t they…we don’t get Earth-directed events every day. True, this flare was not nearly as impressive as an X-Class event, but any kind of direct impact is media friendly. With so much chatter and Saturday’s “Extreme” geomagnetic forecast on the University of Alaska Fairbanks website it was no wonder the public was now bracing for auroras above Canada and the U.S. on Saturday.
Sunspots 1401 and 1402
What the media missed, however, is that there were multiple other space weather websites reporting that the flare did not originate from Sunspot 1401, rather it was the nearby Active Region 1402 that launched the CME, featuring a sunspot of gigantic proportions that is a small (but relatively significant) distance “North” of Sunspot 1401. The case for 1402 was reinforced on Friday when the National Oceanic and Atmospheric Administration announced a less optimistic geomagnetic forecast for the weekend, declaring that the incoming CME that originated from 1402 on Thursday would not result in a direct impact, but rather it would deliver a glancing blow, likely to trigger a minor geomagnetic storm beginning on January 22.
AURORAMAX ALERT: Sunspot 1384 Releases Boxing Day CME, Minor Geomagnetic Storm Expected Dec 28-29
LATEST INFORMATION: A Geomagnetic Storm Warning is in effect until midnight Mountain Standard Time. A minor G1 storm is expected following the impact of an incoming Coronal Mass Ejection (CME). Click the image for NASA’s latest CME Arrival Time Estimate, an animation of an incoming wave of solar wind that originated near Sunspot 1384 on Boxing Day. Observers in northern BC, AB, SK, MB, ON, QC, and NL should be on alert for periods of active auroras on December 28-29. Auroras will be ACTIVE above communities in southern YK, NT, and NU overnight, and will diminish to MODERATE levels by December 30. Check out the latest aurora forecast for Yellowknife, Northwest Territories, updated December 28 at noon MST.
