Lasers may be key to nudging small asteroids away from Earth
Researchers have proposed a space-based laser system to NASA that could turn out to be a cost-effective way to nudge small asteroids away from a collision course with Earth.
Washington: Researchers have proposed a space-based laser system to NASA that could turn out to be a cost-effective way to nudge small asteroids away from a collision course with Earth.
Dr. Richard Fork, an electrical and computer engineering professor at University of Alabama in Huntsville, who is the principal investigator for the Laser Science and Engineering Laboratory, said that the system could move a meteor of the size of meteorite that exploded above Russia away.
Fork said that as far as they`re concerned, they have identified a technically calculable and optimally efficient means of deflecting small asteroids of the Chelyabinsk class.
He said that this method can be explored, quantitatively tested and verified in the very near future and then scaled to address larger asteroids and, possibly, eventually even comets.
The system could be delivered to space to meet a detected threatening object on relatively short notice using a system requiring one "mother" spacecraft relatively near the asteroid and a configuration of multiple microspacecraft more closely orbiting the asteroid.
The laser-equipped spacecraft orbiting within a few kilometers of the asteroid would send trains of ultrashort optical pulses to the reflecting optical systems on the micro-spacecraft directly orbiting the asteroid.
The optical systems on the microspacecraft are designed in turn to redirect and focus specifically designed trains of ultra-short duration optical pulses simultaneously on multiple locations on the asteroid.
A computer based system managing the deflection process includes a capability to locate small areas on the asteroid that are locally flat, optimally located and which also have surface normals oriented for efficient generation of the net deflecting thrust.
The ultra-short pulses from the lasers will superheat the asteroid in the illuminated spots. That causes discharge of plumes of ejecta that will push the asteroid in a direction opposite to that of the ejected material.
The black cloud of ejecta created by the laser impulses becomes clear within roughly 3 microseconds, allowing for the next short burst.