For more materials, measurement, and spacecraft engineering challenges in verifying gravity theory, check out Gravity Probe B [1]. 40+ year effort (spoiler: it

For more materials, measurement, and spacecraft engineering challenges in verifying gravity theory, check out Gravity Probe B [1]. 40+ year effort (spoiler: it confirmed the geodetic and frame-dragging effects of General Relativity). [1] https://einstein.stanford.edu/TECH/technology1.html https://einstein.stanford.edu/TECH/technology1.html