http://www.rdmag.com/News/Feeds/2009/11/environment-a-lightning-strike-in-africa-helps-take-the-pulse-/?wnnvz=cIpb87iV1KLyO8vb Using lightening to measure solar rotation. -- Mr. Clare Jarvis President, Jarvis Computer Software PO Box 1264 Winona, MN 5598707264 (507) 454-2575