Recent comments in /f/space

super_nova_135 t1_ja1ps58 wrote

if a craft blows up, its usually safe to assume that vessel has oxygen tanks and everything needed to create a burning environment. things can explode in space if there's oxygen present and in any vessel with breathable air it is

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dbx999 t1_ja1pgba wrote

What about the fact that laser shots are visible and seem to travel as short segments like bullets that travel at a visible speed. Laser blasts seem to go about as fast as a bullet or tracer round.

And why do laser swords stop at a certain length instead of continuing forward like the beam of a flashlight?

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PyrrhoTheSkeptic t1_ja1ourv wrote

90 mph is almost nothing.

To help you understand, think about tossing a bullet back and forth with a friend. You can do that without your hand getting hurt at all, because the bullet is not going very fast. However, that same bullet being shot from a gun is going very fast coming out of barrel, and it hitting your hand at that speed makes a very significant difference for how it would affect your hand if the bullet hit your hand.

And the speed of a bullet out of a gun is practically nothing compared with going near the speed of light; the forces involved are vastly greater with vastly greater speed.

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Ishidan01 t1_ja1or2o wrote

Bug soft, so it splats. A pebble at 90 mph WILL crack your windshield, or dent your fender.

Force equals mass times velocity SQUARED: velocity means more to force than mass, so if you have a very high velocity, a very small mass carries a lot of force.

Word correction: should have said energy, not force.

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Im_Chad_AMA t1_ja1oaap wrote

The speed of light is 300,000 km/s, or about 671,000,000 miles per hour. Quite a few orders of magnitude larger than 90 mph.

The kinetic energy of an object depends on both its mass and its velocity. A fly against your car is light enough, and the velocity of your car is small enough, that a collision between a car and a fly does nothing to the car. Once you approach lightspeed though, even a speck of dust could wreak havoc

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SCP-Agent-Arad t1_ja1nwpi wrote

Two things: some chemicals don’t need oxygen to burn. Some are better oxidizers than oxygen, like fluorine. It’s actually close to impossible to put out a fluorine fire, since you can’t even smother them, and they’ll even burn things like concrete.

Second, for the sounds of explosions, one way it’s explained in some scifi is that the sounds you are hearing are computer extrapolations. Elite Dangerous is a notable example of this explanation.

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