Sunspot 1520 has been active since it first rotated onto the side of the Sun facing Earth several days ago. It hasn't disappointed and fired off a X1.4 flare today, peaking at 16:52 UTC (11:52 CDT).
The first image is from the AIA 171 channel of the Solar Dynamics Observatory, a satellite whose mission is to keep a close eye on our nearest star. The picture is taken in the Extreme Ultraviolet wavelength and does an excellent job highlighting loops and arcs extending off the sun's surface. I've circled the sunspot group that has been given the number 1520.
X-class is the strongest category of flares, but while a 1.4 isn't the
strongest possible level, it is the largest flare measured so far this summer.
This chart displays a read-out of the x-rays measured from two satellites above the Earth.
The large peak on the right-hand side shows the magnitude and time that the flare was measured by the satellites. Immediately afterward there was radio interference on the sun-ward facing side of the Earth, typically causing the most problems on frequencies below FM radio, especially at higher latitudes. Certain communications and navigational equipment are most impacted. On a 5-point scale, the radio blackouts reached a 3.
This last graphic is a little complicated, but very cool. It's a snapshot from the Coronal Mass Ejection (CME) model for the time period when a CME is expected to pass directly around the Earth.
The model shows that Earth will be right in the path of the CME this time.
A CME is a burst of solar wind and magnetic fields, a sort of storm ejected off the Sun by a solar flare. Which is exactly what happened today.
Most CMEs are fired off away from Earth, so we hardly notice their effects, too high or too low, to the right or to the left. However, when everything is lined up perfectly, we sometimes take a direct hit from a CME. They often take two or three days to arrive, and this one is expected to start impacting the Earth around 01:00 early Saturday morning and continue into the afternoon.
With the strength of the solar storm that occurred today, northern lights are likely as far south as Illinois, Oregon, and New York. However, there's a very good chance they'll be able to be seen much farther south than that, possibly even northern California or Alabama. If the skies are clear, it's definitely worth a look outside.
There's also a website that shows where the northern (and southern) lights are currently visible, as measured by satellite. Via the website SolarHam.com, the link is (here).