Outdoing the dinosaurs: What we can do if we spot a threatening asteroid

Enlarge / We'd like to avoid this. (credit: Science Photo Library/Andrzej Wojcicki/Getty Images)

In 2005, the United States Congress laid out a clear mandate: To protect our civilization and perhaps our very species, by 2020, the nation should be able to detect, track, catalog, and characterize no less than 90 percent of all near-Earth objects at least 140 meters across.

As of today, four years after that deadline, we have identified less than half and characterized only a small percentage of those possible threats.