Io

Assembled from 32 blocks · 2 evidence · 50 related

1. Story
2. The innermost of Jupiter's four large moons, and the discovery that most changed what the Voyager tour was thought to be for. Before 1979 a body that size was expected to be geologically dead. On 8 March 1979, three days after Voyager 1's closest approach, the navigation engineer Linda Morabito was processing an over-exposed image taken to locate background stars when she noticed a crescent-shaped anomaly on Io's limb. It was an eruption plume rising hundreds of kilometres above the surface — the first active volcanism ever seen anywhere other than Earth. The heat source is tidal: Io is squeezed and released by Jupiter's gravity as its orbit is perturbed by Europa and Ganymede, and the resulting friction melts its interior. Not a place on Earth.
3. Knowledge
4. Jupiter
5. Io
6. Connections
7. Jupiter
8. Active volcanism found on Io
9. Voyager 2 closest approach to Jupiter
10. Voyager 1
11. Voyager 2
12. Io
13. The Grand Tour alignment
14. Voyager 1 closest approach to Jupiter
15. Active volcanism found on Io
16. Voyager 2 closest approach to Jupiter
17. Pioneer 10
18. Pioneer 11
19. Galileo
20. Cassini–Huygens
21. New Horizons
22. Juno
23. Pioneer 10 passes Jupiter — the first spacecraft to reach the outer Solar System
24. Pioneer 11 passes Jupiter, bending north toward Saturn
25. Galileo enters orbit around Jupiter — the first outer-planet orbiter
26. Galileo is flown into Jupiter to end its mission
27. Cassini passes Jupiter for a final speed boost toward Saturn
28. New Horizons takes a gravity assist at Jupiter
29. Juno enters polar orbit around Jupiter
30. Evidence
31. An eruption plume was identified on Io's limb on 8 March 1979 in an over-exposed Voyager 1 optical navigation image, the first active volcanism observed beyond Earth. V55 verification basis: NOT CHECKED IN THIS RUN. The author list, volume and date are given from standard citation practice and the page number is deliberately omitted because it was not confirmed.
32. The encounter dates and principal findings at Jupiter, Saturn, Uranus and Neptune, including the Jovian ring, the resolved ring structure at Saturn, the tilted and offset Uranian magnetic field and the newly found moons at both ice giants. V55 verification basis: THE PAGES WERE NOT REACHED — science.nasa.gov is blocked by this session's egress proxy and the search budget was exhausted. Everything attributed here is standard mission record from general knowledge; a curator must confirm each encounter date and each count of newly discovered moons against NASA's own pages.