NASA reports on near-Earth objects program

Near - Earth Objects

Because the NEO population is constantly evolving and being replenished from the main asteroid belt and cometary reservoirs, it consists of objects with a variety of compositions and internal structures. These objects present unique opportunities for future planetary science goals and exploration. In order to realize these opportunities for future NASA studies, an expanded program for NEO disco...

Origin and Evolution of Near-Earth Objects

Asteroids and comets on orbits with perihelion distance q < 1.3 AU and aphelion distance Q > 0.983 AU are usually called near-Earth objects (NEOs). It has long been debated whether the NEOs are mostly of asteroidal or cometary origin. With improved knowledge of resonant dynamics, it is now clear that the asteroid belt is capable of supplying most of the observed NEOs. Particular zones in the ma...

Orbital Simulations on Deflecting Near-Earth Objects by Directed Energy

Laser ablation of a near-Earth object (NEO) on a collision course with Earth produces a cloud of ejecta that exerts a thrust on the NEO, deflecting it from its original trajectory. Ablation may be performed from afar by illuminating an Earth-targeting asteroid or comet with a stand-off “DE-STAR” system consisting of a large phased-array laser in Earth orbit. Alternatively, a much smaller stand...

Rubble-Pile Near Earth Objects: Insights from Granular Physics

NEOKepler: Discovering Near-Earth Objects Using the Kepler Spacecraft

The Kepler Mission has been an irrefutable success. In the last 4.5 years, it has monitored 150 confirmed exoplanets in over 75 stellar systems and detected an additional ∼3,300 planet candidates. Using these data, we have learned the size distribution of planets in our galaxy, the likelihood that a star hosts an Earth-sized planet, and the percentage of stars that contain multiplanet systems. ...