
Check out this article written by Robin George Andrews and published in Science (Vol 390, Issue 6778.) :
Amy Mainzer: Planet Protector
Article synopsis: NASA’s upcoming Near-Earth Object (NEO) Surveyor mission is a dedicated space-based infrared telescope designed to significantly advance planetary defense by hunting down “city-killer” asteroids. These objects, defined as being at least 140 meters (460 feet, of which only ~45% have been discovered) in diameter, are large enough to cause regional devastation but often evade ground-based detection because they are too dark to reflect visible light or approach from the direction of the Sun. Positioned 1.5 million kilometers from Earth at the L1 Lagrange point, the NEO Surveyor will use thermal sensors to spot the heat signatures of these elusive rocks.
Scheduled for a 2027 launch, the mission aims to fulfill a Congressional mandate to discover 90% of potentially hazardous near-Earth objects within a decade, providing the early warning necessary to deploy deflection strategies and avoid future surprise impacts.