Earthlike Gravity

How high do you think you could jump on the moon given you weighed only 1/6th your current weight but were shouldering 30 pounds of spacesuit and backpack?1  Weighing in at 135 pounds, my total weight on the moon including spacesuit and PLSS (backpack) would be only about 50 pounds.  Of course, my leg muscles would be accustomed to supporting my full 135 pounds or 2.7 times as much weight and therefore it's safe to assume that I could jump higher than normal on the moon.  

Under the influence of Earth's gravity I can jump approximately 16 inches off the ground.  In stark contrast, you'll notice from NASA film clips that the physically fit Apollo astronauts couldn't manage any better than this despite the fact that they were--or so we are told--on the moon (see film clips A and B)!  In fact, they should have been able to jump at least 3 feet above the surface of the moon without difficulty.  So, who's got the right stuff--Neil Armstrong, Buzz Aldrin or yours truly?

Granted, our jumping astronauts had significantly better "hang time" than I did which suggests that they truly were on the moon when NASA filmed their various escapades; however, it has been noted by others that the astronaut's movements seen on film happen to be identical to what is witnessed when someone in Earth's gravity--moving at an accelerated pace--is filmed and then the resulting film is slowed down accordingly so that they appear to be moving at a somewhat normal gait under low gravity.  

Here's how it works:  In sequences where 1/6th gravity must be faked, (that is, an object is shown falling to the ground that must be slowed in order to give the appearance of reduced gravity) any voluntary movements made by the astronauts are acted out in say, double-time.  Since the sequence is later going to be slowed down by a factor of 2, the astronaut's voluntary movements will ultimately appear to take place at the normal or expected rate of speed.  However, those events in the sequence in which something goes up and subsequently falls to the ground (including the astronaut himself) cannot be voluntarily sped up as they are under gravity's control.  As such, those events will be slowed to half normal speed in the final film clip thus giving the appearance that the astronauts are moving about in reduced gravity (aside from the fact that their jumps are no higher than they would be here on Earth).  In other words, horizontal voluntary movements end up looking like they're taking place at normal or expected speed whereas involuntary vertical movements appear slower.  This fools the viewer into believing that the astronauts are actually exploring on the moon as opposed to acting on a stage because when something falls, it falls slower than we would experience here on Earth.  

To see this demonstrated, watch each pair of film clips below:

This is the original NASA film clip... Here it is accelerated...
1 Is this astronaut really just kind of shuffling about... ...or is he really running and the film clip has been slowed down to give the impression that he's under the influence of lunar gravity?
2 Maybe this guy's running on another world... ...or maybe he's just be running here on Earth!
3 Is this reality...  ...or is this reality?
4 Why isn't this moon bunny hopping any higher? Because he's not really on the moon!
5 Is this an astronaut... ...or just a Terranaut?

In virtually all of these NASA film clips notice that the surface dust is getting kicked about much farther than one might expect given the apparent speed of the astronauts' movements.  In the film clip #5, for example, would anyone really expect that the lunar soil would be kicked a distance 3 times the height of the astronaut given how slowly he appears to be traveling?  What about film clip #3?  In film clip #4, isn't the lunar soil spreading out beneath the astronaut's boots as though he is hitting the ground much harder (and faster) than is apparent in the film clip?


1. On Earth, the Apollo 11 spacesuit and PLSS pack weighed in at 180 pounds.

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