SOLAR WATCH: Sun Unleashes M3.3 Solar Flare And Coronal Mass Ejection - Could Deliver Glancing Blow To Earth And Trigger Polar Geomagnetic Storms!

August 18, 2013 - SPACE - According to NOAA analysts, a CME hurled into space by an M-class solar flare on August 17th will probably miss Earth. 

Attached image by SDO shows a jet of plasma released by 1818 in the aftermath of the initial M3.3 flare.The Solar-X-Rays are currently above the moderate M-Class threshold as the region continues to reverberate.

The M3.3 solar flare was associated with a 10cm Radio Burst (TenFlare) lasting 25 minutes and measuring 150 solar flux units. Type II and IV sweep frequency events were also detected, including a Type II radio emission with a velocity of 1399 km/s.

WATCH: Long Duration M3.3 Solar Flare - August 17, 2013.

SUMMARY: 10cm Radio Burst
Begin Time: 2013 Aug 17 1908 UTC
Maximum Time: 2013 Aug 17 1915 UTC
End Time: 2013 Aug 17 1933 UTC
Duration: 25 minutes
Peak Flux: 150 sfu
Latest Penticton Noon Flux: 120 sfu
Description: A 10cm radio burst indicates that the electromagnetic burst associated with a solar flare at the 10cm wavelength was double or greater than the initial 10cm radio background. This can be indicative of significant radio noise in association with a solar flare. This noise is generally short-lived but can cause interference for sensitive receivers including radar, GPS, and satellite communications.


ALERT: Type II Radio Emission
Begin Time: 2013 Aug 17 1856 UTC
Estimated Velocity: 1399 km/s
Description: Type II emissions occur in association with eruptions on the sun and typically indicate a coronal mass ejection is associated with a flare event.


ALERT: Type IV Radio Emission
Begin Time: 2013 Aug 17 1909 UTC
Description: Type IV emissions occur in association with major eruptions on the sun and are typically associated with strong coronal mass ejections and solar radiation storms.

However, Earth will pass through the wake of the CME after the cloud itself passes by. This could trigger polar geomagnetic storms despite the CME being off-target. High-latitude sky watchers should be alert for auroras on August 20-21.

The Solar and Heliospheric Observatory (SOHO) photographed the CME billowing away from the sun's southwestern limb on August 17th.

Standard Lasco C2 image with a bright CME now visible.

A coronal mass ejection is shown in the latest coronagraph imagery released by STEREO Ahead.
Two questions remain. How large will it be and will there be an Earth directed component.

Attached is an impressive Earth facing image released by Lasco C2 showing a very bright Coronal
Mass Ejection (CME). A majority of the ejected plasma looks to be directed southwest,
however an Earth directed component is possible.

Sunspot 1818 will remain the largest threat for another isolated M-Class event while it holds on to its delta magnetic configuration. Sunspot 1817 continues to shrink in both size and magnetic complexity as it rotates towards the southwest limb. New sunspot 1824 grew quickly on Saturday and is currently a beta magnetic region. Separation between the leader and trailer spots is being observed. A new sunspot rotated into view off the southeast limb and will be assigned a number today. So far it appears to be stable. The source of a long duration C-Class flare Saturday morning is now just beginning to rotate into view off the northeast limb.

Sunspot AR1818 has a 'beta-gamma-delta' magnetic field that harbors energy for strong flares.
Credit: SDO/HMI

Earth is inside a stream of solar wind flowing from this coronal hole.

Credit: SDO/AIA.

A minor glancing blow at best will be possible by August 20th as the eastern flank of the plasma clouds possibly sweeps past Earth.