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Explain xkcd: It's 'cause you're dumb.
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Pulsar Analogy
The #2 cause of astronomer hand injuries is trying to do vector math when the second axis points off to the right.
Title text: The #2 cause of astronomer hand injuries is trying to do vector math when the second axis points off to the right.


Ambox notice.png This explanation may be incomplete or incorrect: Created by a PULSAR. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.

Ponytail, an astronomer in this comic, explains a pulsar's fast rotation with an analogy about a tape measure retracting. This analogy is inaccurate, as the tape measure starts to rotate because the spring imparts a torque on the body of the tape measure.

However, pulsars actually rotate at their extreme speeds because of the conservation of momentum. As a star collapses into a pulsar, its natural rotation rate is greatly amplified by its shrinking moment of inertia.


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