Okay, so back in reality.. While one Newton is now defined as "the force needed to
accelerate one
kilogram of mass at the rate of one metre per second squared in the direction of the applied force," there's actually nothing about it requiring a vacuum, nor even STP for that matter. Newton claimed F = ma. Force is equal to the product of mass and acceleration and is proportional to both no matter the specific direction, .
That is, Earth's gravity really has nothing to do with it. They chose 1 Nm/s^2 for SI unit simplicity, but g (the standard acceleration due to gravity) has actually been measured and defined as "9.80665 m/s^2" in SI units. Using F=mg then yields F=9.80665 Kgm/s^2. It does not =1.
Newton's most famous equation, F=ma, or his "Second law of motion" does not pertain specifically to Earth's gravity. Indeed, Newton's third
Now notice how any mention of time is completely absent from the above. Mass and distance are all that matter. So what's actually relevant about Special Relativity? Nothing. Past and future time are abstractions. What's real is the present.
from our perspective
over time. Constantly observing Mercury's orbit in real time is of limited practical use. Newton explained the orbit of Mercury from either Mercury's or the Sun's POV at any moment.
Special or General?
Modern Physicists can't seem to agree upon much else. Btw, anyone suggesting Aether theory doesn't explain precession clearly knows no Aether theory.