Head of UA Lunar Lab Part of National Geographic Show
Michael Drake is among scientists talking about where Earth got its water.

By Lori Stiles, University Communications
March 4, 2009

University of Arizona Regents' Professor Michael Drake, head of planetary sciences and the Lunar and Planetary Laboratory, is among scientists featured in this week's episode of the National Geographic Channel series "Naked Science."

Drake will appear in the episode "Birth of the Oceans," which explores where Earth got its water.

The program is scheduled to run on the National Geographic Channel on Thursday at 8 p.m. and 11 p.m. Tucson time. Repeat showings are scheduled at 12 a.m. on Monday, at 4 p.m. on March 12 and 10 a.m. on March 15.

Scientists have been struggling with a great paradox for decades. The paradox is that Earth is too close to the sun to have formed with liquid water, so where did our planet get enough water to cover 70 percent of its surface?

"The question of why Earth has water is one of the most fascinating and important questions we humans face," Drake said, "because without water, we wouldn't be here."

Drake, who is a cosmochemist and a geochemist, proposed a new solution and tested it rigorously in his laboratory.

He realized that before the planets formed 4.5 billion years ago, an enormous expanse of fine dust grains swirled in a vast sea of hydrogen, helium and oxygen around the sun. Hydrogen and oxygen reacted to make water, creating a disk of basically dust surrounded by water.

He discovered in laboratory research that olivine and other common minerals adsorb an astonishing amount of water – enough to create 10 times the volume of water currently found in Earth's oceans.

"I don't mean to pretend that we've got the entire answer yet," Drake said. "But for me it's a no-brainer. At least some, if not most, of Earth's water had to come from adsorption of water onto grains before the planet ever formed."

Extra info


'Birth of Oceans' televised


National Geographic Channel


March 5, 8 p.m.


Resources for the media

Michael Drake