Of all the natural disasters that could befall us, only an Earth impact by a large comet or asteroid has the potential to end civilization in a single blow. Yet these near-Earth objects also offer tantalizing clues to our solar system's origins, and someday could even serve as stepping-stones for space exploration. In this book, Donald Yeomans introduces readers to the science of near-Earth objects—its history, applications, and ongoing quest to find near-Earth objects before they find us.
In its course around the sun, the Earth passes through a veritable shooting gallery of millions of nearby comets and asteroids. One such asteroid is thought to have plunged into our planet sixty-five million years ago, triggering a global catastrophe that killed off the dinosaurs. Yeomans provides an up-to-date and accessible guide for understanding the threats posed by near-Earth objects, and also explains how early collisions with them delivered the ingredients that made life on Earth possible. He shows how later impacts spurred evolution, allowing only the most adaptable species to thrive—in fact, we humans may owe our very existence to objects that struck our planet.
Yeomans takes readers behind the scenes of today’s efforts to find, track, and study near-Earth objects. He shows how the same comets and asteroids most likely to collide with us could also be mined for precious natural resources like water and oxygen, and used as watering holes and fueling stations for expeditions to Mars and the outermost reaches of our solar system.
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.