Last night the Sun unleashed a large coronal mass ejection in our direction. Here is a compilation of images from SOHO's two LASCO cameras, plus a prediction from the new space weather prediction model that I learned about at the American Geophysical Union in December. The storm will arrive at Earth on March 8. The sudden "snow" on the LASCO images is energetic particles from the coronal mass ejection scoring hits on the cameras' detectors.
According to a report issued by NOAA just a few minutes ago:
The CME [Coronal Mass Ejection] that erupted late on March 4 passed ACE [a spacecraft positioned between Earth and the Sun] around 0400 UTC March 7 (11:00 p.m. EST March 6). So far we've observed G2 (Moderate) levels of storming in association with that event. Conditions are currently decreasing for that event, so subsequent G2 storming is not expected at this time. Another CME, part of the recent R3 (Strong) Radio Blackout event at 0024 UTC March 7 (7:24 p.m. EST March 6) is forecast to pass ACE about a day from now and is certain to cause more geomagnetic storming. Images of the CME from the SOHO LASCO coronograph have just backfilled so analysis is underway now to refine the prediction of arrival time and magnitude. Finally, a Solar Radiation Storm is also in progress and levels have just crossed the S3 (Strong) threshold. Updates here as conditions warrant.
Here's more information from NOAA on the effects these solar storms can have on Earth.
Here's a view from SOHO of the storm headed at us: