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Apollo 11 and the Laser Ranging Retroreflector
By Martin English | July 23, 2009
Do a google search on lunar landing hoax and you get thousands of hits. Some claiming the landings were faked, some refuting these ‘hoax’ claims. One thing I’ve never seen mentioned on the hoax sites is the experimentation packages left behind.
The official goal of Apollo 11 was simply to land men on the Moon and return them safely to Earth. Therefore, the mission designers decided to run only a limited number of experiments, and the astronauts were to be kept close to the Lunar Module so as to maintain a healthy margin for safety. They settled on a set of experiments that were dubbed the Early Apollo Scientific Experiments Package (EASEP). The EASEP was used only on the Apollo 11 mission, to be replaced in later missions by the more comprehensive Apollo Lunar Surface Experiments Package (ALSEP).
One experiment that made it into both the EASEP and the ALSEP was the Laser Ranging Retroreflector, or LRRR; an array of mirrors made of quartz that can reflect a laser beam aimed at it from Earth. This elegantly designed experiment had no moving parts, so it was extremely simple to deploy. The LRRR has been used in various experiments, such as precisely determining the distance from the Earth to the Moon (to within 15 centimeters), learning about the internal motion of the Earth and the Moon, and testing Albert Einstein’s theory of general relativity. The LRRRs deployed by Apollo 11, 14, and 15 are still being used in experiments today. In fact, in March 2005 a team from NASA’s Jet Propulsion Laboratory announced that they confirmed Einstein’s Strong Equivalence Principle to double the previous possible precision by using laser range measurements to the LRRR.
Topics: History, Technology | 1 Comment »
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March 6th, 2010 at 9:39 pm
So they were faked?What a shame for them:(