Scout X-4 | Explorer 20

Explorer 20 (IE A, Ionospheric Explorer A, TOPSI, Top Side Explorer or S 48) was designed to measure electron distribution, ion density and temperature, and to estimate cosmic noise levels between 2 and 7 MHz.

Mission Details

  • Launch date: August 25, 1964 at 01:43 PM UTC
  • Launch vehicle: Scout X-4
  • Operator: National Aeronautics and Space Administration
  • Launch site: Vandenberg SFB, CA, USA
  • Mission type: Earth Science