Beyond NASA DART asteroid redirection test
NASA is also developing a first-ever robotic mission to visit a large near-Earth asteroid, collect a multi-ton boulder from its surface, and use it in an enhanced gravity tractor asteroid deflection demonstration.
The spacecraft will then redirect the multi-ton boulder into a stable orbit around the moon, where astronauts will explore it and return with samples in the mid-2020s. This Asteroid Redirect Mission (ARM) is part of NASA's plan to advance the new technologies and spaceflight experience needed for a human mission to the Martian system in the 2030s.
The Asteroid Redirect Mission is one part of NASA's Asteroid Initiative. The initiative also includes an Asteroid Grand Challenge, designed to accelerate NASA's efforts to locate potentially hazardous asteroids through non-traditional collaborations and partnerships. The challenge could also help identify viable candidates for ARM.
NASA plans to launch the ARM robotic spacecraft at the end of this decade. The spacecraft will capture a boulder off of a large asteroid using a robotic arm. After an asteroid mass is collected, the spacecraft will redirect it to a stable orbit around the moon called a "Distant Retrograde Orbit." Astronauts aboard NASA's Orion spacecraft, launched from a Space Launch System (SLS) rocket, will explore the asteroid in the mid-2020s.
Asteroids are left-over materials from the solar system's formation. Astronauts will return to Earth with far more samples than have ever been available for study, which could open new scientific discoveries about the formation of our solar system and beginning of life on Earth.
The robotic mission also will demonstrate planetary defense techniques to deflect dangerous asteroids and protect Earth if needed in the future. NASA will choose an asteroid mass for capture with a size and mass that cannot harm the Earth, because it would burn up in the atmosphere. In addition to ensuring a stable orbit, redirecting the asteroid mass to a distant retrograde orbit around the moon also will ensure it will not hit Earth.
Nuclear weapon against asteroid threat concept
A more advanced asteroid protection concept is to have a high velocity impact into an asteroid to create a crater and then to follow it up with a nuclear weapon exploded in the crater to break up the asteroid. The asteroid debris field would spread so that only a portion of the debris would hit the earth and many small pieces would burn up in the atmosphere.