- Gravity Assist: Explorer 1 & Jim Green’s ‘Gravity Assist’
- The year was 1958; the space race was on. NASA’s first space satellite, Explorer 1, launched a Geiger counter and miniature tape recorder into space that registered astonishingly high radiation levels above Earth. This discovery gave humanity its first glimpse of the Van Allen radiation belts, named for James Van Allen.
- 2018-03-01 18:57:00 UTC