The Pioneer probe with its cross-like
thermal louvers
The Atlas Able Pioneer probes
were probably the first to have
a hydrazine propulsion system,
seen here during pre-launch
preparations at Cape Canaveral
Atlas-Able rocket with Atlas 20D as
booster stands ready at launch
complex 14 at Cape Canaveral
Pioneer P-3 probe is
launched by an
Atlas-Able from
Cape Canaveral
at 0726 UT on
26 November 1959