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Explain xkcd: It's 'cause you're dumb.
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Newton's Trajectories
With just one extra line, he could have anticipated the 2003 film The Core, but some things are too audacious for even the greatest visionaries.
Title text: With just one extra line, he could have anticipated the 2003 film The Core, but some things are too audacious for even the greatest visionaries.


Ambox notice.png This explanation may be incomplete or incorrect: Created by a cannonball - Please change this comment when editing this page. Do NOT delete this tag too soon.

The comic shows a sphere, representing the Earth, with three sets of what appear to be spaceships on three trajectories. One set is released with sufficient velocity to remain in a stable (elliptical and not circular in theory as they are not shot horizontally) orbit, while the other two fall towards the Earth. This is a replica of Newton's famous thought experiment involving a cannon on a high mountain, which demonstrates the effects of gravity on objects orbiting the Earth.

Here, Newton's thought experiment is used to make the figurative and at the same time literal observation that a slight variation in parameter (impetus of the push) leads to totally different results. Society can choose the way of peaceful colonization of space and be able to explore the stars. Or it can choose to wage war and send intercontinental ballistic missiles (ICBMs) on a crash course and end the human civilisation in fire.

Some - e.g. Elon Musk or Stephen Hawking and probably Arthur C. Clarke prominently - think or thought, respectively, the only chance of the human species to survive on long-term is to go to other planets.

The title text alludes to the film The Core in which the trajectory would go straight to the center of the earth. This would be only possible, if you also change the angle (to straight upwards or straight downwards) and not only the force or by steering during the flight/the drill.


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