Mariner 10 Spacecraft

Mariner 10 spacecraft hangs from ceiling during preparationsWhile the 747 was impressing airlines and passengers around the world, another Boeing project was headed far into the depths of space. The Boeing Aerospace Mariner 10 probe, begun in 1971, was launched from the Kennedy Space Center, Fla., in 1973.

It made the first dual-planet spaceflight by launching to Mercury using the gravitational pull of Venus. The probe's two television cameras, a radio transmitter and data collection equipment were protected from the sun's heat by solar panels.

By March 1974, Mariner 10 had transmitted hundreds of television images and large quantities of data about the two planets back to Earth. It revealed cloud circulation patterns on Venus and the lack of a magnetic field, and then took the first high-resolution photographs of Mercury's cratered surface.

The National Society of Professional Engineers named Mariner 10 as one of the top 10 engineering achievements of 1974.

First launch: Nov. 3, 1973
Classification: Interplanetary space probe
Basic diameter: 54.4 inches
Solar panels: 106 inches long, 38 inches wide
Gross weight: 1,160 pounds
Science package: 170 pounds