Solar eruption misses Earth, auroras likely anyway

On Sept. 4th around 1600 UT, a magnetic filament erupted, hurling a bright coronal mass ejection (CME) off the sun's northwestern limb.

Today's edition of http://spaceweather.com features a close-up view of the blast from NASA's Solar Dynamics Observatory. The CME is not expected to hit Earth. Nevertheless, auroras are possible in the nights ahead.

A solar wind stream flowing from a coronal hole is heading our way, due to arrive on Sept. 5th or 6th. NOAA forecasters estimate a 50% chance of high-latitude geomagnetic activity when the solar wind hits. With the approach of northern autumn, Arctic nights are getting dark again--dark enough to see the Northern Lights.

People in Alaska, Canada and Scandinavia should keep an eye on the night sky this weekend.