This article highlights that three approaches for the Apollo mission were considered and investigated early in the program: direct ascent, Earth orbit rendezvous, and lunar orbit rendezvous. Direct ascent would entail a direct shot from Earth to the moon, requiring an enormous rocket assembly, named the Nova rocket that required 15 first stage engines and would dwarf the Saturn V eventually selected as the launch vehicle. It also required a massive lunar landing vehicle to return the astronauts from the moon directly to Earth. At liftoff, the first stage burned 15 tons of fuel a second, requiring approximately 50,000 horsepower to power the fuel pumps to feed the engines. The Apollo 13 movie followed the actual flight with a fair degree of accuracy, recognizing that it had to compress four days of real-life tension into a two-hour motion picture. The film dramatized the explosion of the oxygen tank by showing the astronauts being thrown about in the cabin. In reality, the astronauts only heard a bang and then the warning alarm for low electrical bus voltage.
Advanced Technology Lunar Astronomy Mission, the Moon as an Immense Optical Bench in Vacuum
