When Billy Bob Thorton’s character approaches Bruce Willis, Ben Affleck and Steve Buscemi to save the world from impending doom in 1998’s blockbuster film “Armageddon” they only had 18 days to prevent an asteroid the size of Texas from annihilating life on Earth. In the years since, real NASA scientists have spent countless hours observing NEO’s – Near Earth Object’s – and painstakingly tracking their past and future orbits to find which will be the next major asteroid to cross path’s with Earth. And while we are yet to find one that with certainty will be the next major Chelyabinsk or Tunguska Event, that hasn’t stopped researchers from thinking about ways to prevent such a collision from happening.
Since 2018, a joint planetary defense operation between NASA, Johns Hopkins Applied Physics Laboratory, and the space agencies of Europe, Italy, and Japan have come together to design the DART Mission. The “Double Asteroid Redirection Test” is scheduled to launch from Vandenburg Air Force Base in California at 11:20 PM MST Tuesday 23 November aboard a SpaceX Falcon 9 rocket for its one-way trip to the binary asteroid Didymos. While Didymos is not a threat to Earth, it was chosen as the perfect testing ground for a potential new technology that could be used for future asteroid redirect missions.
On 2 October 2022 the DART spacecraft will collide with the smaller of the two asteroids in the Didymos binary system. Unlike most spacecraft full of scientific experiments, the primary craft is essentially a 500kg (1,100 lb) inert mass with little more than a guidance system and antenna powered by a small solar array. A few days prior to impact a small CubeSat designed by the Italian Space Agency will seaparte form the main spacecraft and trail behind to image the impact and relay both narrow and wide field images back to Earth.
The plan is such that the impact will have a very small effect on the asteroid at the moment of collision, just a half a millimeter per second. That is enough change however that as Didymos continues its trek around the sun, Earth based telescope will be able to see how its orbit changes. This information will help us plan future missions to move asteroids of varying sizes out of orbits that may be deemed hazardous to Earth or other potential risks. A follow up mission is scheduled to revisit Didymos 5 years after the impactor to study its geology and the longer term affects of the initial mission.
Here’s to hoping it works and we don’t have to sacrifice Ben Affleck again.
The Backyard Astronomer 