Galileo Galilei famously began to do work on the acceleration of gravity by dropping balls from the Learning Tower of Pisa. He found that objects of different masses accelerated at the same rate which was a departure from Aristotle’s view that heavier objects accelerated faster.
It has been found that any two objects with mass have a gravitational attraction to each other and Earth’s gravitational attraction to any and all objects (ignoring air resistance) is calculated to be a known constant of 9.81 m/s^2 or 32.2 ft./s^2.
However, if the gravitational force were altered by 0.00000000000000000000000000000000000001%, our sun would not exist. And neither would we. This is amazing precision built into our earth.
Let me give you an illustration at how precise this value of gravity is that helps us to survive is. Take a tape measure and put it from your garage to the end of your driveway. If you set gravity at a particular “inch” line on that tape measure, and move the magnitude of gravity just one inch proportionally either in front or in back of that line, we cease to exist.
However there is a problem. The tape measure does not go from your garage to the end of your driveway, it goes across the entire known universe. You change gravity that much over the entire known universe and we do not exist.
Absolute precision from God alone.