Measuring Density in Space: How Do You Do It?

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The problems with space...

Just pondering how you would measure an object's density when in space or a vacuum...

Was thinking attach it to a spring and use the spring constant but would a spring work in an area with a low gravitational field strength?

What are other people's ideas?
 
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You need to apply a known force, then measure the acceleration of the body. You can do this with a spring (if you know the spring constant). It takes some practice but if you can stretch the spring and hold a constant length as the body accelerates you will be applying the needed constant force.
 
do you use the natural frequency of the spring or look at the time period and root mass?
 
a bit confused :s
 
If the object is reasonable in size, insert it in your thermos bottle, then fill the thermos from a bottle filled to a known volume.

Have 2 of your astronaut friends spin you while you're doing it if you're having trouble poring and stuff.

Or use a syringe for the purpose instead, and inject water into the thermos till it's full and measure the displacement.
 
As for the mass, use a centrifugal scales.
 
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