NASA is preparing to launch a probe to study an asteroid that could decimate Earth by the late 22nd century, and explore ways to avert a crisis.
The asteroid, dubbed Bennu, passes Earth’s atmosphere every six years.
Scientists believe it has edged even closer since its discovery in 1999 and they wanted to get a better idea of its trajectory.
There are no proven methods to destroy an asteroid, however experts have raised the use of nuclear missiles, laser beams and massively powerful propulsion engines as possible ways to avert a potential disaster.
If the 500-metre wide asteroid hit Earth, it would cause a blast equivalent to triggering three billion tonnes of explosives, 200 times the strength of the atomic bomb that hit Hiroshima, NASA researchers said.
“It [Bennu] may be destined to cause immense suffering and death,” Arizona University professor of planetary science and lead researcher on the NASA mission, Dante Lauretta told the Sunday Times.
The NASA mission is also aiming to take samples of the asteroid, which could give scientists a rare look at ancient substances.
Bennu is a “carbonaceous asteroid”, which comes from the early solar system and may have seeded Earth.
Professor Lauretta estimated the chance of impact with Earth to be one in 2,700, and would occur between 2175 and 2196 if it happened.
NASA’s OSIRIS-REx probe will be launched in September on a $1 billion, seven-year mission.
Should it conclude that Bennu will smash into Earth, here are three ways we could stop it.
Australian National University asteroid expert Dr Andrew Glikson told The New Daily that nuclear missiles could be used to avert an impending disaster.
“We could send nuclear missiles to hit the asteroid when it is far away from Earth,” Dr Glikson said.
He said it was important this was not done while the asteroid was in Earth’s atmosphere.
Director of the Asteroid Deflection Research Center at Iowa State University, Bong Wie, shared this view. He told Space.com that a spacecraft carrying a nuclear warhead could possibly be sent to destroy an asteroid.
“Laser ablation” would vaporise rock to create jets that would push the asteroid off a course with Earth, according to The Planetary Society‘s director of science and technology, Dr Bruce Betts.
Dr Glikson agreed: “Lasers could be focused on the asteroid to change its course and hopefully have it divert and miss Earth.”
By heating the surface of an asteroid with a laser, a plume of gas could be produced which could possibly be controlled to modify the trajectory of the asteroid, the Acta Astronautica science journal found.
An electronically powered spacecraft propulsion system usually would garner electrical energy to change the velocity of a spacecraft.
But to work on Bennu, a spacecraft propulsion device would need to be successfully attached to the asteroid first.
The European Space Agency’s (ESA) “Advanced Concepts Team” has begun exploring the possibility of this method already.
The ESA study looked at using electronic or kinetic energy and found a lot more research had to be undertaken before this was possible.