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There could be meteors hitting the atmosphere close to the speed of light

phys.org

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Re: There could be meteors hitting the atmosphere close to the speed of light

#3

Post by perl4ever »

I am annoyed by the way the article says "close to the speed of light" and then revises that to "1% of the speed of light". You can call 90% "close", or 99%, or 99.9%, etc. But 1% is not close.

Also, again, in the beginning it says "relativistic" and then switches to "sub-relativistic". I don't know exactly what the latter is, but surely it implies not relativistic?

Re: There could be meteors hitting the atmosphere close to the speed of light

#4

Post by mirimir »

perl4ever wrote: post #3

I am annoyed by the way the article says "close to the speed of light" and then revises that to "1% of the speed of light". You can call 90% "close", or 99%, or 99.9%, etc. But 1% is not close. Also, again, in the beginning it says "relativistic" and then switches to "sub-relativistic". I don't know exactly what the latter is, but surely it implies not relativistic?

There's lots of apparently sloppy editing. For example:

> Despite having a sound theoretical basis, the question remains as to whether or not meteors larger than a grain of dust enter Earth's atmosphere at sub-relativistic or relativistic speeds. These would be meteors that measure 1 mm (0.04 in), 1 cm (0.4 in), or 10 cm (4 in) in diameter.

I mean, what, they're quantized?

Re: There could be meteors hitting the atmosphere close to the speed of light

#6

Post by pdonis »

mirimir wrote: post #4
perl4ever wrote: post #3

I am annoyed by the way the article says "close to the speed of light" and then revises that to "1% of the speed of light". You can call 90% "close", or 99%, or 99.9%, etc. But 1% is not close. Also, again, in the beginning it says "relativistic" and then switches to "sub-relativistic". I don't know exactly what the latter is, but surely it implies not relativistic?

There's lots of apparently sloppy editing. For example: > Despite having a sound theoretical basis, the question remains as to whether or not meteors larger than a grain of dust enter Earth's atmosphere at sub-relativistic or relativistic speeds. These would be meteors that measure 1 mm (0.04 in), 1 cm (0.4 in), or 10 cm (4 in) in diameter. I mean, what, they're quantized?

> There's lots of apparently sloppy editing.

Typical for phys.org. They're going for eyeballs and clicks, not accuracy.

Re: There could be meteors hitting the atmosphere close to the speed of light

#7

Post by pdonis »

ycombonator wrote: post #5

Physicists out there, Shouldn’t the mass of these objects increase as they are traveling at that speed according to Einstein. Also does the increase in mass means size of just mass within the same size ?

> Shouldn’t the mass of these objects increase as they are traveling at that speed according to Einstein.

"Relativistic mass" is an outdated concept; it's really just another name for "total energy".

> does the increase in mass means size of just mass within the same size ?

I'm not sure what you mean. Objects traveling at relativistic speeds will be length contracted, so if anything their apparent "size" decreases.

In any case, as has been pointed out upthread, the speeds actually being observed are only about 1% of the speed of light, so relativistic effects are too small to matter.

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