The Complete Book of Spaceflight: From Apollo 1 to Zero Gravity

Gemini 4 Ed White becomes the first American to step outside his spacecraft and drift in the vacuum of space. He is
attached to the spacecraft by an umbilical line and a tether line, wrapped together in gold tape to form one cord. NASA
Canaveral. Gemini 4’s main goals were to evaluate the
spacecraft and crew during a lengthy stay in space, rendezvous
with the spent Titan II second stage, carry out
the first American spacewalk, and continue testing the
Orbital Attitude Maneuvering System (OAMS).
The plan to fly in formation with the Titan second
stage proved a real learning experience in orbital
dynamics. To catch something in Earth’s atmosphere
involves simply moving as quickly as possible in a
straight line to the place where the object will be at the
right time. Gemini 4 showed that this does not work in
orbit. When the astronauts tried to fly toward the target,
they got farther and farther away! The problem is
that adding speed also raises altitude, moving the
spacecraft into a higher orbit than its target. This paradoxically
causes the faster-moving spacecraft to slow
153