The European Space Agency (ESA) has started work on the Rapid Apophis Mission for Space Safety, or Ramses — a spacecraft that will study a large asteroid as it flies near Earth in April 2029.
The vehicle will start following 99942 Apophis before it gets close, and tag along to observe how Earth’s gravity affects the 1,230-foot asteroid itself as well as its path. Ramses should learn how the asteroid’s shape, surface, orientation, and spin change as it gets within 20,000 miles of the planet.
The mission should also help scientists better understand the composition and structure of an asteroid. There’s a chance Earth might trigger landslides and quakes that expose material buried underneath the surface, the ESA said.
Ramses is equally an opportunity to gauge humanity’s quick response to a potentially threatening asteroid. The agency has to launch the spacecraft in April 2028 to meet Apophis in time, and is starting prep work using existing resources from the Hera mission. to speed up the process. Ideally, humans will scramble reconnaissance missions so that they can redirect asteroids in time.
A full commitment isn’t expected until an ESA ministerial meeting in November 2025. If it goes ahead, though, it’ll get an American follow-up as NASA steers its OSIRIS-REx spacecraft (now rebadged OSIRIS-APEX) to reach Apophis about a month after the Earth fly-past.
NASA has already contributed to asteroid deflection through its DART mission, which studied the results of a spacecraft deliberately colliding with a small asteroid.
This asteroid won’t hit Earth within at least 100 years. Large asteroid fly-bys are also relatively rare, typically occurring only once every 5,000 to 10,000 years. This could ensure that Earth is ready if there is a likely collision, though, and it’s a rare opportunity to track a space object that our planet is likely to influence in a significant way.