If you shined a flashlight into the sky, where does the beam go?

Question

Does it just die on the way up, like it would if you shined it somewhere far away? Does it hit a star up in the sky?

Answer 1

From How Stuff Works, where a similar question was asked:

"When you turn on a flashlight, you are creating a source of photons (see How Light Works for details on photons). The photons leave the flashlight and they immediately start to spread out in a cone-shaped beam. Provided that they don't hit anything, each individual photon travels through space forever. So it is not that the photons "run out of gas" on the way to the moon and stop. What happens instead is that, by the time they reach the moon, the photons have spread out tremendously. So few photons hit your eye at any one time that you cannot detect the flashlight. "

So, technically, there is SOME chance that a photon from your flashlight might SOMEDAY hit a star. But even at the speed of light -- it would take a REALLY long time!

Answer 2

*Some* of the light will eventually hit a star or another planet -- but not much.
Light from a source follows the inverse-square law: for every 2 feet the light travels, it's 4 times less concentrated. That's because the beam "spreads out", not because the light loses energy or anything...it goes on forever, but keeps spreading out, so the light hitting any particular area after just 50 feet or so is very little of the original light that left the flashlight.

Answer 3

Hell sure. I nevertheless do it too. greater generally in the process the summer season time. i've got consistently been involved approximately astronomy and was hoping that interior the destiny the mild from my fairly tiny flashlight could attain the action picture star (as though that is going to ever be seen whilst it has the sunlight to compete with). i'm going to although do it, no count number how ridiculous that is. probably that is purely a experience of connecting by utilising some means with the mild that travelled everywhere between 4 and sixteen,308 years to get right here (Alpha Centuri & Hipparcos 5926).

Answer 4

A flashlight emits light waves that travel continuously. If you shined it into space then the beam would keep going although the light would spreadout over a givin distance.

Answer 5

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Answer 6

The distance depends upon the power of the beam.

Answer 7

Jesus!!!!.... It goes to the local shop!!!!