WEIGHT OF THE WORLD

By Dan Miller
May 18, 2007

Recently I read that planet Earth weighs almost six sextillion metric tons.
It might be easier for you to digest the exact figure numerically....
It's 5.972,000,000,000,000,000,000 metric tons (give or take a few pounds here or there).

I immediately thought.... how can anyone possibly know how much a planet weighs?

For each of us, as individuals, it's easy to know our weight.
Standing on my bathroom scales I'm quickly reminded that I weigh roughly 230 pounds.
In essence, the scales are set to measure the gravitational pull between the Earth and me, or anything else I put on those scales.

But, as you know, the Earth is not resting on any scales....
And since the Earth is floating in space, shouldn't it -- in theory -- be weightless?
Well.... no.

Amazingly to me, there are brilliant scientists who can calculate these things, using equations and mathematical formulas that, somehow, I never got to in school.
According to those guys, everything across the wide expanses of the entire universe -- every planet, moon, star, galaxy, stone, cricket or even every feather -- has a gravitational pull on everything else.... thus, creating weight.

Here's the simplest explanation that I can grasp, or explain....
If there were only one object floating in all of existence, it would be weightless and size-less. But since there are untold trillions of things scattered across the great universe, everything becomes relative to everything else.

Scientists say even one bowling ball has an infinitesimal gravitational pull on another bowling ball.... which might explain some of my gutter balls.

19th century English poet Francis Thompson expressed it nicely:

"All things by immortal power,
Near and far
Hiddenly
To each other linked are,
That thou cans't not stir a flower
Without troubling of a star."

Here's a bit of good news.
The force of gravity is different on other planets, so if you weigh 180 pounds here on Earth, you'd weigh only about 68 pounds on Mars.

But stay away from Jupiter.
You'd weigh more than 425 pounds there!

That's all for now.
I'm feeling the gravitational pull on my eyelids, so I'm going to bed.

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