Solar Storm Headed Our Way / Aurora Alert Tonight Sept. 6-7

This picture was taken through my little 80mm (3-inch) refracting telescope on Tuesday, September 5th. The flaring group, 2673, is at right. The other large sunspot group is region 2674. Credit: Bob King ** Check the update at the end of this article **

The large sunspot group, active region 2673, that grew in great haste over the weekend, has proceeded to shoot out flares like a 4th of July fireworks display. Seven moderate or M-class flares erupted Monday and five more on Tuesday. During one of Monday’s flares, the spot group launched a CME or coronal mass ejection toward the Earth, set to arrive this morning.

Material from a CME — the cloud and tendrils expanding away from the sun shown here — that erupted around 3 p.m. CDT September 4 is headed toward Earth. The photo was taken with a coronagraph, which blocks the sun with a metal disk (blue), so the camera can capture what’s happening nearby. Click here for a video time-lapse. Credit: NASA/ESA

Space weather experts predict it will whip up moderate to strong (G2 to G3) geomagnetic storms, which could make for good auroras as far south as Illinois tonight. The shock wave will hit around 10 a.m. (Central time) and reverberate long into the night. There’s only one rub — it’s full moon! Bright moonlight robs the aurora of its glory, but if we truly do get a strong storm, there should be some sign of it such as an arc or occasional bright rays picket-fencing the northern sky.

Since the group has been a good source of flares, more auroras may arrive over the weekend. By that time, the moon won’t be as much of a problem. Make sure to regularly check the Aurora 30-minute forecast to see if the aurora has arrived and how far south it extends.

Wow! One of the biggest flares in many years, an X9.3, erupted in region 2673 earlier today. This photo shows the blast in far ultraviolet light taken by NASA’s Solar Dynamics Explorer. Credit: NASA / SDO

** UPDATE: Region 2673 erupted with an extremely powerful X9.3 flare at 7:02 CDT on September 6th that produced a coronal mass ejection partially directed toward Earth. Space weather forecasters have also extended the G2 and G3 storm alerts to Thursday and Friday nights September 7th and 8th. Auroras are highly likely before the week is out!