How much does planet Earth weigh?
It would be more proper to ask, “What is the mass of planet Earth?”1 The quick answer to that is: approximately 6,000,000,000,000 ,000,000,000,000 (6E+24) kilograms. The interesting sub-question is, “How did anyone figure that out?” It’s not like the planet steps onto the scale each morning before it takes a shower. The measurement of the planet’s weight is derived from the gravitational attraction that the Earth has for objects near it. It turns out that any two masses have a gravitational attraction for one another. If you put two bowling balls near each other, they will attract one another gravitationally. The attraction is extremely slight, but if your instruments are sensitive enough you can measure the gravitational attraction that two bowling balls have on one another. From that measurement, you could determine the mass of the two objects. The same is true for two golf balls, but the attraction is even slighter because the amount of gravitational f
