Friday the 13th of April 2029 will be our lucky day.
Apophis, a 375-metre-wide asteroid, will safely pass Earth at a distance of less than 32 000 kilometres. For a few hours, Apophis will be closer than satellites in geostationary orbit and visible to the naked eye from Europe and Africa.
Space agencies have sent a number of spacecraft to asteroids, but we have never had a mission at an asteroid as it sweeps past a planet. This grand natural experiment offers a unique opportunity to study in real time how an asteroid responds to a strong external force – and the European Space Agency aims to have a front-row seat.
To this end, ESA’s Space Safety Programme has proposed the Rapid Apophis Mission for Space Safety (Ramses). If approved, Ramses would launch a year ahead of the Apophis flyby, travelling through space to rendezvous with the asteroid months before its encounter with Earth.
Ramses would use a suite of scientific instruments to measure Apophis’s size, shape, composition, rotation and trajectory as it is pulled and stretched by Earth’s gravity. It wouldalso deploy two smaller spacecraft at the asteroid to study Apophis up-close.
Apophis poses no danger to Earth during the flyby, but an asteroid of this size passes thisclose to our planet only once every roughly seven thousand years. By seizing this exceptionally rare opportunity to study an asteroid before, during, and after a planetary encounter, Ramses would help us prepare for the day that we may need to deflect a hazardous object on a collision course with Earth.
A cornerstone of the Planetary Defence segment of ESA’s Space Safety Programme, Ramses would demonstrate Europe’s ability to rapidly design, launch and operate a mission to an asteroid of high importance.
When the world looks up to see Apophis passing overhead, Ramses could be flying alongside, uncovering the secrets of the Solar System’s ancient building blocks, and helping us learn how to protect our planet from any that come too close for comfort.