Mach 1 is the speed of sound at sea level
No, Mach 1 is the speed of sound, regardless of altitude.
When a gyroscope is spinning, it resists being pushed around because it is interacting with the Earth, the stars, and distant galaxies. If those objects didn't exist, the gyroscope would have no inertia.
No, it resists being pushed around because it has mass (inertia). That doesn't require interaction with other objects.
The Space Studies Institute is championing the cause, inviting tax-deductible donations.
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It’s safe to stop reading when you get to the above sentence.
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