warned that the United States was unprepared for an asteroid impact event, and developed and released the "National Near-Earth Object Preparedness Strategy Action Plan" to better prepare.

Most deflection efforts for a large object require from a year to decades of warning, allowing time to prepare and carry out a collision-avoidance project, as no known planetary defense hardware has yet been developed. It has been estimated that a velocity change of just .035 m/s ÷ t (where t is the number of years until potential impact) is needed