The sphere, which looks like an oversized soccer ball, was released by Mission Specialist Winston E. Scott during the STS-87 spacewalk and flew freely in the forward cargo bay for about 30 minutes.
Remote control of the AERCam is performed through two-way UHF radio communications, with data regarding the status of the free-flyer's systems transmitted back to the operator.
The exterior of the free-flyer sphere is covered with a 6⁄10-inch-thick (15 mm) layer of Nomex felt to cushion any inadvertent contact with a spacecraft surface and prevent damage.
The AERCam's thrusters, basic avionics, solid-state rate sensors, attitude hold electronics, nitrogen tank and hand controller are identical to those used on the SAFER.
"The nanosatellite-class spherical Mini AERCam (Miniature Autonomous Extravehicular Robotic Camera) is just 7.5 inches (190 mm) in diameter and weighs approximately 10 pounds (4.5 kg).