Status: Active
Launch date: September 8, 2016
Full name: Origins, Spectral Interpretation, Resource Identification, and Security – APophis EXplorer
OSIRIS-APEX is on its way to explore a giant asteroid that, in 2029, will nearly hit Earth. The mission aims to take modern humanity’s closest call with a major asteroid and turn it into an opportunity: a chance to better understand asteroids, learn more about how the Solar System formed, and help prevent future impacts.
On April 13, 2029, the asteroid Apophis — which is about as tall as the Empire State Building and three times as wide and long — will pass closer to Earth than the orbits of some satellites. If this asteroid hit Earth, the energy of the collision would be roughly equivalent to 1,000 of the most powerful nuclear bombs in the United States’ arsenal.
But Apophis won’t hit Earth. Instead, OSIRIS-APEX will watch from a distance as Apophis flies by, then catch up to study the asteroid in more detail. The spacecraft will map Apophis, track its trajectory, and eventually fire thrusters to stir up its surface. The information that OSIRIS-APEX gathers will help scientists understand the forces that shape asteroid orbits, improving our ability to predict what might hit us in the future — and maybe, one day, even redirect an asteroid on a collision course with Earth.
OSIRIS-APEX is as close to a “freebie” as space missions get. It’s the bonus phase of a previous NASA mission, called OSIRIS-REx, which completed its goals with fuel to spare.
The spacecraft is already on a course to Apophis. Shutting OSIRIS-APEX down now would not only be needlessly wasteful, it would squander a rare opportunity: an encounter this close with an asteroid like Apophis only happens near Earth once every 7,500 years.