# Usain Bolt Vs. Astronauts In A Zero Gravity Foot Race

Submitted by: daegog 1 week ago in
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So THAT'S how you slow him down, take away gravity. The Olympic committee should look into that.
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Male 9,893
Correction, that is not Zero Gee.  It's not even free-fall.

That is LOW-Gee.
Male 8,605
megrendel Well, it's not even low-gee, is it? Isn't it simply simulated weightlessness via parabolic arcs in flight?
Male 9,893
squrlz4ever Yes, I guess I should have said 'simulated low-gee'.

It is done via parabolic arcs in flight.  Basically the aircraft overcomes inertia by it's control surfaces while the people inside are free to follow their own inertia.  By varying the aircraft's controls, the people inside experience anything from positive, to neutral, to negative gees.
Male 1,608
squrlz4ever What we feel - the pull towards the centre of the earth is already a mix of forces (gravitational, centripetal, etc.) .  What the vomit comet flights do, is to attempt to minimize the net force on the passengers. When you're in orbit around the Earth (i.e. at ISS) you are in a micro gravity situation primarily because the ISS is ever so slightly slowing down constantly.  we have to periodically boost it back up to continue orbiting.

A true orbit around the Earth would feel like zero G because we have perfectly balanced the gravitational attraction to the earth with the force resulting from our acceleration around the planet.  (a constant speed orbit is not constant velocity.  velocity is a vector - speed and direction - acceleration is the change of velocity in time, by changing direction you are moving in is by definition acceleration.  This acceleration needs a net force acting on the body. )  In a geostationary orbit the "felt" amount of gravity would be infinitesimal (but not zero,  don't go outside and let go!)

You can't escape gravity - anywhere - you are always being pulled toward something.  You can have practically zero gravitational force (by being really, really far away from everything) and you can have practically zero net force (balancing net gravity with net acceleration by changing speed and/or direction)

Riding the vomit comet and experiencing near weightlessness is not 'simulated'.  it is a man-made environment with near weightlessness, just like the ISS.  The ISS version is simply more stable and lasts longer.  The net force on your body you feel as weight is always a mix of gravity and acceleration.
Male 8,605
punko Points taken. Thanks, Punko.
Male 207
This is awsome.
Male 17,643
Jesus he's still fast
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