Aster › Space program › Didymos
Didymos
Position on the route: 14/130 · level needed 32 · journey (Mk0 engine) 6.0 h
By the numbers
| Diameter | ≈ 780 m |
|---|---|
| Year | 2.11 years |
| Moon | Dimorphos, ≈ 160 m |
| DART | 26 September 2022 |
The story
Didymos (Greek for ‘twin’) is a binary near-Earth asteroid found in 1996: a 780-m main body and, circling it every 11 hours 55 minutes, 160-m Dimorphos. NASA’s DART craft hit Dimorphos on 26 September 2022 at 22,000 km/h and shortened its orbit by 32 minutes: the first time humanity has changed the motion of a celestial body.
There was no threat; the aim was to test a planetary-defence technique. The material thrown off formed a tail thousands of kilometres long. ESA’s Hera craft (launched in 2024, arriving in late 2026) will measure the crater and the interior in detail.
Missions
- DART (NASA, 2021–2022): the kinetic impact
- Hera (ESA, 2024–): the follow-up survey
- LICIACube (ASI): satellite images of the impact
Colony note
A binary system; an observation and mining outpost. Barely any gravity.
What probes bring back
- Around 780-m Didymos circles 160-m Dimorphos: a binary asteroid.
- NASA’s DART craft hit Dimorphos on 26 September 2022 and cut its orbit from 11 h 55 min to 11 h 23 min: the first deliberate change to a body’s orbit by humans.