Bennu
Position on the route: 4/130 · level needed 22 · journey (Mk0 engine) 2.9 h
By the numbers
| Diameter | ≈ 490 m |
|---|---|
| Year | 436.6 days |
| Type | B-type, carbonaceous |
| Sample | ≈ 120 g, 2023 |
The story
Bennu is a dark, carbon-rich near-Earth asteroid found in 1999: a rubble pile left over from the first millions of years of the Solar System. OSIRIS-REx (NASA) arrived in 2018, took a sample from the surface on 20 October 2020 (so much rock came in that stones propped the lid open) and dropped the capsule in the Utah desert on 24 September 2023.
The sample contains amino acids, nucleobases, salts and water-formed minerals: Bennu’s parent body once held briny water. It is evidence that some of the ingredients of life could have come from space. The chance of an Earth impact in 2182 is about 1 in 2,700: small, but watched.
Missions
- OSIRIS-REx (NASA, 2016–2023): brought a sample home
- OSIRIS-APEX: the same craft, now bound for Apophis
Colony note
Carbonaceous ore and ice; with so little gravity, living there is theoretical. A mining base.
What probes bring back
- OSIRIS-REx took a sample from the surface in 2020 and on 24 September 2023 brought about 120 g of it home.
- The sample holds amino acids, salts and water-formed minerals: Bennu’s parent body once held briny liquid.
- A rubble pile: the boulders cling together weakly and the inside is porous.