NASA and the European Space Agency are joining forces with other institutions to launch a program that will test their ability to pull off a major task: Prevent asteroids from hitting Earth.
Asteroids have been crashing into the Earth for billions of years and have been disastrous in the past, like when an asteroid ushered the extinction of the dinosaurs. And though we're not currently in danger of being struck by a massive space rock, scientists have been toying with lots of ideas to prevent threatening asteroids from hitting Earth.
One of these ideas has given birth to the Asteroid Impact & Deflection Assessment program, under which two spacecraft will be launched at a binary asteroid that orbits near the Earth. One will nudge the rock to see if its orbit can be changed while the other will study the makeup of the asteroid itself.
The idea behind the program is to determine whether kinetic energy can be used to divert an asteroid from colliding with Earth. Or, more simply put, NASA and the ESA are trying to see if it is possible to bump an asteroid off course.
"To protect Earth from potentially hazardous impacts, we need to understand asteroids much better -- what they are made of, their structure, origins and how they respond to collisions," Dr. Patrick Michel, lead investigator for the ESA, told scientists at the European Planetary Science Congress. "AIDA will be the first mission to study an asteroid binary system, as well as the first to test whether we can deflect an asteroid through an impact with a spacecraft."
A practice run of the potentially world-saving mission is set for May 2022, when the binary asteroids Didymoon and Didymos orbit close to Earth. AIDA crafts will be launched 18 months earlier, in October 2020, to meet the asteroids. Not only does will AIDA aim to see if an asteroid can be diverted, but it will also study the makeup of the rock itself.
The two-part mission is split between NASA and the ESA. For the first part of the program, the ESA's Asteroid Impact Mission will send a small lander to Didymoon to measure its internal structure and density through radar waves.
For the second part of the program, NASA's Double Asteroid Redirection Test spacecraft, steered by ESA's lander, will slam into the center of Didymoon. Since Didymoon orbits the much larger Didymos, scientists hope that the impact will shift both asteroids.
Though Didymoon is only 525 feet wide, if AIDA is successful, the same principle should still apply to much larger, and actually threatening asteroids.