Near-Earth Object Surveyor

The Near-Earth Object Surveyor space telescope (NEO Surveyor) is designed to help advance NASA’s planetary defense efforts to discover and characterize most of the potentially hazardous asteroids and comets that come within 30 million miles of Earth’s orbit. These are collectively known as near-earth objects, or NEOs.

NEO Surveyor consists of a single scientific instrument: a 50 centimeter (nearly 20 inch) diameter telescope that operates in two heat-sensing infrared wavelengths. It will be capable of detecting both bright and dark asteroids, which are the most difficult type to find.

After launch, NEO Surveyor will carry out a five-year baseline survey to find at least two-thirds of the near-Earth objects larger than 140 meters (460 feet). These are the objects large enough to cause major regional damage in the event of an Earth impact. By using two heat-sensitive infrared imaging channels, NEO Surveyor can make accurate measurements of NEO sizes and gain valuable information about their composition, shapes, rotational states, and orbits.

NEO Surveyor employs an innovative observation strategy to independently discover new asteroids and comets and determine their orbits with enough accuracy to allow them to be found again. In five years of survey operation, NEO Surveyor is designed to make significant progress toward meeting the U.S. Congress's mandate to NASA to find more than 90 percent of all NEOs larger than 140 meters in diameter.