Apophis
Position on the route: 3/130 · level needed 24 · journey (Mk0 engine) 2.4 h
By the numbers
| Diameter | ≈ 340 m |
|---|---|
| Year | 323.6 days |
| Semi-major axis | 0.92 AU |
| Closest approach | 13 April 2029, ≈ 32,000 km |
The story
When it was found in 2004, Apophis briefly counted as the most dangerous asteroid known; as the orbit was refined, the 2029 and 2036 impact odds fell to zero and an impact is now excluded for at least a century. The 13 April 2029 pass is still a unique science opportunity: nothing this large comes this close. Earth’s gravity will change its orbit and its spin.
It will be visible to the naked eye from Europe and Africa: a bright star-like point crossing the sky for hours. OSIRIS-APEX and ESA’s Ramses mission aim to watch the encounter at close range. In the game it is one of the cheapest interplanetary targets: a little more fuel than the Moon.
Missions
- OSIRIS-APEX (NASA, 2029): approach to Apophis
- Ramses (ESA, planned): before and after the pass
- Goldstone and Arecibo radar observations
Colony note
No permanent life; a mining station and an observation outpost. Very weak gravity: a vehicle that bounces once can bounce away.
What probes bring back
- On 13 April 2029 it will pass about 32,000 km above Earth’s surface: closer than the geostationary satellites (≈36,000 km) and visible to the naked eye.
- An impact is ruled out for at least a century; during the pass Earth’s gravity will change its orbit and its spin.