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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 the Earth, with three apparent spaceships on separate trajectories. One set is released with sufficient velocity to remain in a stable orbit, while the other two fall towards the Earth. This is a slight modification of Newton's cannonball, a thought experiment demonstrating the planetary effects of gravity.


Here, Newton's cannonball is used both to observe humanity’s technological future (interstellar travel, availability of advanced technology to the masses, and constant scientific improvement, or nuclear desolation and the extinction of our species) and to underscore that argument by pointing out the inherent metaphor in the experiment: the cannonball can only escape the atmosphere by achieving high velocity (i.e. escape velocity). Similarly, technological progress will only deliver us from nuclear extinction if it happens quickly; otherwise, mankind will destroy itself.

The phrase "slip the bonds of Earth" comes from the sonnet "High Flight" written in 1941 by John Gillespie Magee Jr., an American pilot in the Second World War. Portions of this poem appear on the headstones of many interred in Arlington National Cemetery, particularly aviators and astronauts.

The title text alludes to the unfortunate film The Core, involving, obviously, drilling to the center of the Earth. If there had been one extra line that declined much earlier than the others, its trajectory would point itself toward the center of the earth. Apparently, not even Newton could predict such a disaster.


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