Spaceguard

Arthur C. Clarke coined the term in his novel Rendezvous with Rama (1973) where "Project Spaceguard" was the name of an early warning system created following a fictional catastrophic asteroid impact.

The impact of one of its fragments created a giant dark spot on Jupiter over 12,000 km across, and was estimated to have released an energy equivalent to 6 teratons of TNT (600 times the world's nuclear arsenal).

Generally, the Spaceguard organizations formed within individual countries are associated with the international foundation or with the NASA efforts only by name, common interests, and similar goals.

An extension to the project gave NASA the mandate of reducing the minimum size at which more than 90% of near-Earth asteroids are known to 140 m.[6] The 2002 Eastern Mediterranean event and the Chelyabinsk meteor (Russia, February 2013) were not detected in advance by any Spaceguard effort.

New survey projects, such as the Asteroid Terrestrial-impact Last Alert System (ATLAS) program[7][8] operated by the University of Hawaii, aim to greatly increase the number of small (down to approximately 10 m) impactors that are discovered before atmospheric entry—typically with days to weeks of warning, enabling evacuations of the affected areas and damage mitigation planning.

I mean a typical small mission ... takes four years from approval to start to launch ...Lack of a master plan and dangers of false alarms have been pointed out by Stefan Lövgren.