Physics (classical), most often, refers to pre-1900 physics, while modern physics refers to post-1900 physics, which incorporates elements of quantum mechanics and relativity.

GRAVITY

Question…

How is a “Gravity field” the product of a body’s motion through curved “spacetime”?

In NASA’s 2004 Gravity Probe B experiment, highly-precise spheres were gyroscopes (spun mechanically), enclosed in a spacecraft to measure gravity, and shielded from the effects of all other forces.

http://www.nasa.gov/pdf/168810main_gpb_nutshell_ppt.pdf

In our ISS Falling Bodies Gravity Test, we will observe, monitor and track spheres of materials with different magnetic permeability moving through curved “spacetime”, to better understand how the four known natural forces: Gravity, Electromagnetism, Strong nuclear and Weak nuclear forces influence the spheres indivdually and collectively.

 Heliophysics

Cassini Mission