In a hope to save Earth, scientists want to crash space ships into asteroids.
More than 100 scientists have come out in support of further research into a possible major asteroid collision with Earth, an all too real threat, say the group which includes prominent physicists and astronomers from around the world.
“Unlike other natural disasters, this is one we know how to predict and potentially prevent with early discovery,” say the scientists whose signed letter was released earlier this week. The group states that over 1,700 “Near Earth Objects” or NEOs have so far been discovered as hazardous, with more being detected at a rate of four per day.
“As such it is crucial to our knowledge and understanding of asteroids to determine whether a kinetic impactor is able to deflect the orbit of such a small body, in case Earth is threatened,” reads the letter.
The movement comes under the heading, “I Support AIM,” in reference to the Asteroid Impact Mission, a joint proposal of NASA and the European Space Agency (ESA), set for launch in the year 2020. The two space agencies plan to send two spacecrafts called AIM and DART to the binary near-Earth asteroid (65803) Didymos, whose trajectory will bring it close to Earth. The 800 metre-wide Didymos is orbited by its own 160 metre-wide moon, which is the true target of the mission. The AIM spacecraft will reach Didymos’ moon first and set about observations and mapping in preparation for DART – the Double Asteroid Redirection Test – which upon arrival will be flown smack into the moon, hopefully altering its pathway while AIM records the results.
The findings will be crucial to any future attempts at deflecting doomsday rocks from hitting Earth, says Kai Wünnemann, Head of Division Impact and Meteorite Research at the Museum of Natural History in Berlin. “Simulations of asteroid deflection by impact are only as good as the knowledge we put into them. With AIM and DART, we have the unique opportunity to test our simulations and feed them with new knowledge about the asteroid’s responds on impact,” says Wünnemann.
The quest to keep the Earth safe from asteroid impacts has picked up speed in recent years, in part due to the 2013 surprise explosion of the Tunguska asteroid which flew down from the skies and blew up over the town of Chelyabinsk Oblast, Russia. The asteroid estimated to be about 65 feet wide exploded with a force 30 times more powerful than an atomic bomb and injured 1,500 people.
Two approaches to asteroid diversion are currently being proposed – one being the kinetic impact outlined by the AIM mission and the other, called the gravity tractor, imagines orbiting a large spacecraft nearby an asteroid so as to slowly and minutely influence the object’s orbit by the gravitational pull of the spacecraft.
In September of this year, NASA launched the OSIRIS-REx space probe, headed to meet up with the asteroid Bennu in 2018. OSIRIS aims to be the first mission to reach and orbit an asteroid and then return back to Earth with samples from the rock. The mission is being supported by the Canadian Space Agency which has outfitted OSIRIS with a laser altimeter to measure and map the surface of Bennu.