Aster › Space program › 1I/ʻOumuamua
1I/ʻOumuamua
Position on the route: 106/181 · level needed 480 · journey (Mk0 engine) 68.1 h
By the numbers
| Length | ≈ 100–1,000 m |
|---|---|
| Speed | ≈ 26 km/s |
| Found | 19 October 2017 |
| Name | Hawaiian: ‘scout’ |
The story
ʻOumuamua was found on 19 October 2017 by Robert Weryk with Pan-STARRS in Hawaii: the first object seen to come from outside the Solar System. It passed 0.25 AU from the Sun on 9 September 2017 and left on a hyperbolic orbit: it will not return.
It looked long and thin (an axis ratio of several to one) and its brightness varies every 8 hours. No coma was seen, yet a small acceleration not explained by gravity was measured; explanations include hidden outgassing and hydrogen ice. The name is Hawaiian for ‘a messenger from afar arriving first’.
Missions
- Spitzer, Hubble, VLT: observations (no mission)
Colony note
A passing visitor; an observation outpost only.
What probes bring back
- Robert Weryk found it on 19 October 2017 with Pan-STARRS in Hawaii: the first object seen to arrive from outside the Solar System (1I). Its speed relative to the Sun is about 26 km/s.
- It looked long and thin (an axis ratio of several to one) and its brightness swings every 8 hours; no coma was seen but a small acceleration not due to gravity was measured. Its name is Hawaiian for ‘scout’ or ‘messenger’.