Deep in the forest of West Greenwich, Rhode Island, MIT graduate students anxiously scan the skies for sprites, halos and elves.

These students are not filming the next Harry Potter movie, nor are they experimenting with new drugs they made in lab. They are trying to detect Schumann resonances, the extremely weak vibrations that occur in the Earth’s upper altitudes at the tail-end of a thunderstorm.

“The best place to measure Schumann resonance is far away from a lightning storm,” says Earle Williams, principal research engineer in Civil and Environmental Engineering at Massachusetts Institute of Technology. “It’s like listening to a concert, next to a bass drum. You can only appreciate the ‘natural phenomena’ if you stand back.”

Williams, who will host the upcoming Pinhead Town Talk, “Sprites, Elves and Blue Jets: Strange lights in the sky” on Tuesday, August 11, is an expert in the electrical dynamics of thunderstorms and science behind the Earth’s luminous events.

Sprites, for example, are bright red-orange electrical discharges in the upper atmosphere, initiating from lightning’s electrostatic field. “They involve less current and are dimmer than ordinary lightning,” Williams explains.

Sprites, which can extend up to 50 miles above ground and expand over several hundred square miles, are characteristic of the post-lightning “drizzling” stage of massive thunderstorms and last only a few tens of milliseconds, far shorter than typical lightning; they are visible to the naked eye, if one is trained to see them.

“They are spectacular, appearing as giant, jellyfish shapes, with descending tendrils and broad, diffuse tops,” he says.

Williams has been fascinated with the inner workings of the naturally oscillating global circuit for years. He is able to conduct measurements of electromagnetic variations between the ground and the “ionosphere,” or the charged uppermost part of the atmosphere, around the entire circumference of the planet – all with a few pieces of equipment in a single location, like the one in Rhode Island.

The meteorological research that Williams and colleagues around the world conduct may also provide crucial insight into fundamental climate issues. Lightning frequency and strength and atmospheric temperature changes, for example, can potentially help explain global warming and weather phenomena like El Niño.

“It’s like measuring the heartbeat of planet earth,” remarks Williams.

This free Town Talk is on Tuesday, August 11 and starts at 6 p.m. in the Conference Center in Mountain Village. Town Talks are co-produced by the Telluride Science Research Center (TSRC) and Pinhead Institute, and are sponsored by the Telluride Mountain Village Owners Association (TMVOA). For information please visit www.telluridescience.org or call Nana Naisbitt, TSRC executive director at 970/708-0004.