Lithuim

Lithuim t1_iu6094j wrote

Bilateral (humans) or radial (jellyfish) symmetry helps keep you balanced so you can move with purpose, and reduces the needed genetic complexity.

You don’t need totally separate developmental pathways for your left arm and your right arm, just a genetic copy-paste.

You’ll just swim in circles with one large fin and one short fin.

Both the vertebrates and the arthropods settled on bilateral symmetry long ago, so practically all land animals are symmetrical like that.

Radial symmetry is more popular among the jellyfish/anemone/sea urchin types in the ocean.

Asymmetric anarchy like bivalves and sponges still has a few very ancient holdouts.

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Lithuim t1_iu5npxv wrote

During editing the computer will remove all the pixels above a certain green-ness threshold and replace them with whatever CGI background you want to use.

This rapidly automates the film editing process so that a human doesn’t have to manually crop each frame.

You can theoretically use any color value for this, but green is the most common because humans don’t come in green and don’t wear green very often.

Choose red or yellow and you risk editing out a person standing in slightly off lighting too. Choose blue and you’ll edit out everyone’s pants.

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Lithuim t1_iu4q9aj wrote

The child is then relaying that reaction force to the ground.

The wagon accelerates in one direction and the Earth accelerates in the other.

Since the Earth is 24 orders of magnitude more massive, the F=ma acceleration of the earth is 24 orders of magnitude smaller.

Wagon goes 2mph east, earth goes 0.000000000000000000000002mph west.

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Lithuim t1_itpy94q wrote

First you start with observations. People watched the skies for centuries, out of both boredom and religious intent. They meticulously recorded events.

After a while it became apparent that major events weren’t simply random - solar and lunar eclipses seemed to come in clumps, and always correlated with full or new moons.

With enough data on this, medieval astronomers could start to work out the mathematics behind it - the Earth and the Moon have very predictable orbits and will repeat the same cycles over and over again.

Today the orbits are well modeled, and we can predict eclipses with extremely high accuracy.

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