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Physics/Backpacks in microgravity conditions?


In order to support background research for my story, I am wondering wether an astronaut could use a cargo backpack if he or she were in space, or wether it would be impractical. Could one perhaps mount a robotic arm on the backpack to convey items from the pack to to the astronaut? Of course, I am aware that current arrangements have the astronaut's backpacks housing the life-support equipment, and so far I have found little about astronaut tool-carrying arrangements except -- I think -- some variety of front pouches.

And do you could builf oxygen tanks to hold more pressure if you were to make them geodesic spheroids rather than spheres or cylindroids?

Thank you very much for your time

Hello Julian,

In addition to belly pouches, I think the current arrangements sometimes also have the astronaut's tools or supplies in a package tethered to the astronaut by a short cord. I don't know if this is done, but it occurs to me that if the astronaut needed to temporarily put a hand tool down (in the terminology of gravity inhabitants), Velcro on the tool and on the opposite shoulder makes sense. What you suggest could be done, but I don't see practicality in such a plan. But since it is your story, your creativity may be able to develop a situation this is beyond my imagination but does that require such a plan. Because there are occasions where a third hand would be useful.

I am not sure of the meaning you intend for "geodesic spheroids". Geodesic refers to a length-minimizing curve - a path.
The path a plane would use to fly from Alaska to Scotland would be a "Great Circle" path, also known to mathematicians as a geodesic. This path would take the plane closer to the North Pole than either the takeoff point or the landing point.
A spheroid may be a sphere but in general is either prolate (like the ball used in American football or rugby) or oblate (like a lentil).
So I will assume that just the term "spheroid" will work for what you are visualizing. I do not know much about strength of manufactured shapes. I assume these shapes would be made in similar ways: a sphere being made by welding 2 hemi-spheres together or a spheroid being made by welding 2 hemi-spheroids together. The weld would typically be the weakest feature. So my guess points to there not being a difference - assuming equivalent materials.

I hope this helps,


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Steve Johnson


I would be delighted to help with questions up through the first year of college Physics. Particularly Electricity, Electronics and Newtonian Mechanics (motion, acceleration etc.). I decline questions on relativity and Atomic Physics. I also could discuss the Space Shuttle and space flight in general.


I have a BS in Physics and an MS in Electrical Engineering. I am retired now. My professional career was in Electrical Engineering with considerable time spent working with accelerometers, gyroscopes and flight dynamics (Physics related topics) while working on the Space Shuttle. I gave formal classroom lessons to technical co-workers periodically over a several year period.

BS Physics, North Dakota State University
MS Electrical Engineering, North Dakota State University

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