GEMINI 4 was the second manned mission of the GEMINI series and carried J. A. Mcdivitt and E. H. White on a 4-day, 62-orbit, 98-hr flight from June 3 to June 7, 1965. The spacecraft was conical and ... had a diameter of 3.05 m at the large end, which was the rear of the spacecraft and which was covered by a fiberglass heat shield to protect the craft during reentry. The objective of the mission was to test the performance of the astronauts and capsule for an extended length of time in space. The spacecraft was transported to space with a titan rocket. White performed a 23-min eva (walk) in space attached to the spacecraft by an 8-m tether. Medical and engineering experiments were performed. The scientific experiments performed were visual and photographic. The experiments performed were electrostatic charge (msc-1), proton-electron spectrometer (msc-2), triaxial magnetometer (msc-3), two-color earth limb photos (msc-10), inflight exerciser (m-3), inflight phonocardiogram (m-4), bone demineralization (m-6), synoptic terrain photos (s-5), synoptic weather photos (s-6), dim and twilight phenomena (s-28), radiation (d-8), and simple navigation (d-9). The mission was successful, and the spacecraft landed in the pacific on June 7, 1965.