26-METER ANTENNAS

The 26-meter (85-ft.) diameter antennas are used for tracking Earth-orbiter satellite spacecraft, most of which are in orbits between 160 and 1,000 kilometers (100 and 630 miles) above the Earth.

The X-Y mount allows the antenna to point low on the horizon to pick up the fast-moving Earth orbiters as soon as they rise into view. The maximum tracking speed is three degrees per second.

The 26-meter antennas were originally built to support the manned Apollo missions to the moon, which took place between 1967 and 1975.