NASA Wanted Astronauts to View Venus Up-Close

In a little over a week, we’re all going to be looking skyward and focusing our sights (safely) on Venus as it crosses the disk of the sun. It's going to be a fantastic view, especially since most of us only ever see Venus as a tiny dot of light in the sky. But in 1967, NASA considered giving three astronauts a really rare view of Venus by sending them on a flyby around the second planet from the sun.

The mission was developed under the Apollo Applications Program (AAP) that was designed to build on and apply Apollo-era technology to greater goals in space. Out of the AAP NASA hoped to see Earth orbiting laboratories, research stations on the moon, and manned interplanetary missions. In 1967, this was America’s future in space.

One of the interplanetary targets was Venus. After visiting the planet with the unmanned Mariner 2 spacecraft in 1962, NASA learned that the planet lacks a strong magnetic field, has an extremely hot surface generated in the lower atmosphere or surface, and that the cosmic radiation in the interplanetary space was survivable. NASA also learned that it was worth going back. There was undoubtedly more to Venus locked under its thick cloud cover.

To get a crew there, NASA would use a revised Apollo spacecraft. Like the lunar missions, it was a tripartite design composed of a Command and Service Module (CSM), and Environmental Support Module (ESM), and a third habitable section. Here’s how the mission was designed to play out.

A three-man crew, nestled in the CM, would launch on a Saturn V. The CSM would perform the same functions it did during the Apollo lunar missions: its onboard computer would serve as the primary guidance and navigation system, provide the main reaction control, and act as the principle telemetry and communications link with mission control. Really, the mission would be a simple of matter of engineers rewriting the computer’s commands to send the crew to Venus instead of the moon. The hard part is keeping them alive and well during the 400 day mission. This is where the other modules come into play.

With no purpose for a Lunar Module on a Venus flyby, the spidery spacecraft would be swapped out for the larger ESM. Once in Earth orbit, the crew would separate the CSM from the rest of the spacecraft, turn around, and dock with the ESM. Then they could open the hatch and transfer between the vehicles. The ESM was designed as the principle experiment bay on the mission and would provide long term life support and environmental control to the whole spacecraft configuration.

With the CSM and ESM docked, the Saturn V’s upper SIV-B stage would fire and send the whole thing towards Venus. But instead of jettisoning the spent rocket stage, the crew would re-purpose it -- neither of the other two module gave them a comfortable living space. In the ESM the astronauts would have everything they’d need to refurbish the rocket stage and turn it into their main habitable module and recreational space. Solar panels lining the outside would provide power to the whole spacecraft.

The mission planned to launch sometime during the month-long window between Oct. 31 and Nov. 30 1973; the dates offered a quick transit to Venus and the year was expected to be a quiet one for solar activity, minimizing the crew’s exposure to dangerous solar radiation.

The outbound leg of the mission was expected to last 123 days. The crew would arrive at Venus sometime in the month of March 1974 and pass just 3,340 nautical miles -- about 3,834 statute miles -- above the surface as they whipped around to begin the 273 day trip back to Earth. The mission would end in a splashdown sometime in December 1974.

Read more at Discovery News