# Ramses by European Space Agency

Canonical page: https://technooptimist.io/spaceflight/ramses
Frontier: [Spaceflight](https://technooptimist.io/spaceflight.md) · Field: Planetary missions · Company: [European Space Agency](https://technooptimist.io/companies/esa.md)
Stage: Proto (2 of 5: Research → Proto → Pilot → Deploy → Scaling)
Updated: last update 2026-02-10, facts checked 2026-10-11
Goal: Study how a 375 m asteroid reacts when Earth's gravity squeezes it during a once-in-thousands-of-years close pass, knowledge needed to deflect a dangerous asteroid one day.
Status: Passed critical design review in Feb 2026; OHB Italia building it for a spring 2028 launch.
Next milestone: Build, assemble and test the spacecraft, target 2027

## Milestones

| Status | Milestone | Date | Slip |
| --- | --- | --- | --- |
| Done | Member states release funds for preparatory work | Jul 2024 |   |
| Done | €63M preparatory contract with OHB Italia | 17 Oct 2024 |   |
| Done | Critical design review completed | 6 Feb 2026 |   |
| Done | €81.2M build-and-test contract signed | 10 Feb 2026 |   |
| Current | Build, assemble and test the spacecraft | 2027 |   |
| Planned | Launch | Q2 2028 |   |
| Planned | Arrive at Apophis | Feb 2029 |   |
| Planned | Apophis passes 32,000 km from Earth | 13 Apr 2029 |   |

## Upcoming events

- **2027**: Build, assemble and test the spacecraft
- **Q2 2028**: Launch
- **Feb 2029**: Arrive at Apophis
- **13 Apr 2029**: Apophis passes 32,000 km from Earth

## Most important updates

- **10 Feb 2026**: ESA signs €81.2M contract with OHB Italia to build Ramses for a spring 2028 launch. ESA signed the contract that starts construction, assembly and testing of Ramses, four days after its critical design review concluded. ([our story](https://technooptimist.io/stories/esa-signs-81-2m-contract-with-ohb-italia-to-build-ramses-for-a-spring-4ef2edda.md) · [original source](https://www.esa.int/Space_Safety/Planetary_Defence/ESA_awards_contracts_for_Ramses_mission_to_Apophis))
- **17 Oct 2024**: ESA signs €63M contract with OHB Italia to start Ramses before full funding, to reach Apophis in time. ESA and OHB Italia signed a €63 million contract at the International Astronautical Congress in Milan to start buying long-lead parts and finish Ramses's design. ([our story](https://technooptimist.io/stories/esa-signs-63m-contract-with-ohb-italia-to-start-ramses-before-full-9460a7d2.md) · [original source](https://www.esa.int/Space_Safety/Planetary_Defence/ESA_moves_forward_with_Apophis_mission_preparations))

## Current obstacles

- **A deadline that cannot move**: Apophis passes on 13 April 2029 regardless; a late launch means missing the event, so the craft must be built in 3.5 years.
- **Launch ride still being settled**: ESA lists a spring 2028 window; a shared launch with JAXA's Destiny+ has been offered but not confirmed.

## Physics limits

- **Almost no gravity to work with**: A 375 m asteroid pulls so weakly that orbiting or landing takes very slow, careful flying, and a lander can bounce off if it touches down too fast.
- **Tidal effects may be subtle**: Earth's pull during the pass may shift boulders, change the spin or trigger small slides, but the changes could be small and need precise before-and-after measurements to see.

## How it works

### Hera heritage: A copy of a proven design

Ramses reuses the spacecraft design of Hera, ESA's first asteroid mission, which saves the years a new design would take.

### Before and after: Watch the asteroid change

Arriving two months early, it measures Apophis's shape, spin and gravity before, during and after the pass, to see what Earth's tides changed.

### CubeSats: Two small helpers, one lands

Two CubeSats are released at the asteroid; one lands to measure gravity and listen for quakes on the surface.

### JAXA: Japanese parts

JAXA supplies the solar arrays and a thermal infrared imager, and has offered a shared launch with its Destiny+ mission.

## Spec sheet

| Spec | Ramses | Provenance |
| --- | --- | --- |
| Apophis diameter | About 375 m | reported |
| Apophis closest approach | About 32,000 km from Earth | reported |
| Industrial contracts so far | About €150M (OHB Italia) | reported |
| CubeSats carried | 2 (one a lander) | reported |
| Development time | 3.5 years | reported |

Provenance: reported = stated by the company; estimated = our estimate; sample = a sample figure.

## About European Space Agency

ESA is the European intergovernmental space agency with 23 member states. It operates Earth observation systems, the International Space Station, deep-space missions and the Ariane rocket family. The Hera mission is ESA's planetary-defence follow-up to NASA's DART impact test.

- Develops Ariane rockets and Copernicus Earth-observation satellites; participates in the International Space Station.
- Hera mission to asteroid Didymos measures how NASA's 2022 DART impact deflected it, validating planetary defence.
- Multinational agency with 23 European member states; 2026 budget €8.26 billion.

- Founded: 1975
- Headquarters: FR
- Status: government
- Website: https://www.esa.int
- Partners, customers, investors: NASA (partner); Airbus Defence and Space (supplier); Thales Alenia Space (supplier)

Company page: https://technooptimist.io/companies/esa.md

## Related programs

More from European Space Agency:

- [Hera](https://technooptimist.io/spaceflight/hera.md) (Deploy)
- [ExoMars Rosalind Franklin rover](https://technooptimist.io/spaceflight/rosalind-franklin-rover.md) (Pilot)
- [PLATO](https://technooptimist.io/spaceflight/plato.md) (Proto)
- [JUICE (Jupiter Icy Moons Explorer)](https://technooptimist.io/spaceflight/juice.md) (Deploy)
- [Euclid](https://technooptimist.io/spaceflight/euclid.md) (Deploy)
- [Ariel](https://technooptimist.io/spaceflight/ariel.md) (Proto)

Everything in Spaceflight: https://technooptimist.io/spaceflight.md

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