Play the video above to see these stories on AZ Illustrated Science for Tuesday, may 7:

TEN YEARS AFTER the Aspen Fire burned nearly 85,000 acres of mostly Ponderosa pine and destroyed 340 homes and businesses on Mt. Lemmon northeast of Tucson, scars from the blaze remain. Georgia Davis reports.

TREE RINGS reveal a lot, including wildfire history. The University of Arizona is the founding institution for tree-ring research, and Don Falk, director of the Tree Ring Laboratory, tells Georgia Davis what research can show.

REMOTE SENSING using satellites to study all aspects of wildfires - active fires, fire scars fuel load - is under way at the UA. Georgia Davis speaks with Steve Yool, a professor in the UA School of Geography and Development.

GEOTHERMAL ENERGY abounds in some parts of the world, but may be an under-used resource in the United States. The federal government is providing $20 million for a study of geothermal potential throughout the country. In the state, the Arizona Geological Survey is leading the effort. Georgia Davis interviews Director Lee Allison about the project.