RAMSES
A European mission planned to fly alongside Apophis as it passes close to Earth in 2029.
Key facts
- Agency
- European Space Agency (ESA)
- Type of mission
- Asteroid rendezvous
- Target
- Asteroid 99942 Apophis
- Launched
- Planned for 2028
- Status
- In development
RAMSES, the Rapid Apophis Mission for Space Safety, is a planned European spacecraft built largely on the design of Hera. Its aim is to reach the asteroid Apophis before its close pass of Earth on 13 April 2029, so that it can watch the encounter as it happens.
Before, during and after
OSIRIS-APEX will arrive just after the flyby. RAMSES is planned to arrive about two months before it. Together they would give a before-and-after view: the shape, spin, surface and interior of an asteroid as Earth's gravity tugs on it. Scientists expect the pull to change its rotation and perhaps to set boulders rolling or trigger small landslides on its surface.
RAMSES would carry cameras and spectrometers, and release cubesats, some of which may try to land, measure tremors with seismometers and probe the interior with radar.
A tight schedule
The 2029 flyby cannot wait, so the mission needs to launch in 2028, giving it an unusually short time to be built. ESA began early work in 2025.
Why it matters to meteorites
The way an asteroid responds to being shaken depends on whether it is solid rock or loose rubble, and on how strong its pieces are. Meteorites give the strength of the pieces; RAMSES would show how the whole body behaves.
Key dates
| Date | What happened |
|---|---|
| 2028 | Planned launch. |
| February 2029 | Planned arrival at Apophis. |
| 13 April 2029 | Apophis passes about 32,000 km above Earth's surface. |
See where this mission fits among all the others in the mission timeline.
Did you know?
RAMSES is named after the Egyptian pharaohs, to go with the Egyptian name of Apophis.
A close pass like Apophis's in 2029 is thought to happen for an asteroid of its size only once every few thousand years.