What do you think is the most important invention of the 20th Century and why?

the internet

Explanation:

The computer rendered the typewriter obsolete and made writing in long-hand a thing of the past, but it took the internet to truly turn the computer into the monster it is today. While the airplane shrank our planet to the point that one could fly from New York to London in six hours, the internet made it possible to be there in a few seconds. It allows truth to make it into and out of repressive countries, it foments revolutions, and spreads lies at the speed of light. It also gives anyone the ability to buy and sell almost anything imaginable, find and torment old school mates, watch the latest you-tube videos, and even find their perfect life partner, all for a few bucks a month. Oh, and you can also get useful information off it if you don’t mind scrolling through 15,000 hits to find out just how long snails really live. Where would we be without it?

giant impact theory - the moon was formed from the collision between earth and another mars-sized body.

colliding planetesimals hypothesis - the moon was formed from the same cloud of material as earth.

capture hypothesis - the moon was locked into orbit by earths gravity as it was passing by it.

accretion hypothesis - the moon was formed from collisions and combining of planetesimals.

i think this is right, if not and you know better let me know.

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