A solar wind stream is buffeting Earth's magnetic field, sparking Southern Lights around the Antarctic Circle. Ian Stewart sends this picture from a jetty near Hobart, Tasmania:

© Ian Stewart
Not long after sunset a friend rang to ask whether a faint arc of light crossing over the southern sky was an aurora. It was!" says Stewart. "This is the first time in the new solar cycle that I have managed to photograph the Aurora Australis. Previous events either have not been strong enough to view at 43o South, or have occurred during our daytime. Perhaps this is the beginning of a good aurora season for the southern hemisphere."

ALERT: The solar wind is intensifying and a moderate geomagnetic storm is in progress. High latitude sky watchers in both hemispheres should be alert for auroras.