Near-Earth Objects: Finding Them Before They Find Us

Humans may fret over earthquakes, nuclear meltdown, and heart attacks, but only collision with a near-Earth object has “the capacity to wipe out an entire civilization with a single blow.” Balancing the wonders of astronomy with the looming potential for an epic, planetwide disaster, Yeomans, a fellow and research scientist at NASA’s Jet Propulsion Laboratory, explores the origins of near-Earth objects—asteroids, comets, meteors, and meteoroids—and the threat they can pose to our planet. We see how the surfaces of Earth and every other rocky planet or satellite in the solar system are pockmarked with craters formed by the bombardment of asteroids and comets; our Moon itself coalesced from massive chunks of rocky material struck off a very young, molten Earth by one such massive collision. Further investigations reveal evidence that large-scale impacts wiped out most of Earth’s species on at least two occasions. Arguing that “dinosaurs became extinct because they didn’t have a space program,” Yeomans describes how scientists have backed the creation of watchdog projects, like the Spacewatch Survey, Spaceguard Goal, and most recently the Near-Earth Observation Program, dedicated to identifying and monitoring the movements of potentially deadly asteroids and comets. Though brief, Yeomans’s book is an accessible and far-ranging primer on the science of near-Earth objects. 20 halftones, 19 line illus., 6 tables. (Dec.)