top | item 22390615

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

13 points| c89X | 6 years ago |phys.org | reply

8 comments

order
[+] simonCGN|6 years ago|reply
1% of the speed of light does not sound to me as “close” to the speed of light.
[+] ycombonator|6 years ago|reply
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 ?
[+] pdonis|6 years ago|reply
> 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"Relativistic mass" is an outdated concept; it's really just another name for "total energy".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.

[+] perl4ever|6 years ago|reply
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?

[+] mirimir|6 years ago|reply
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?

[+] Apocryphon|6 years ago|reply
Troubling- if any were to hit one of the poles, it could cause a massive impact.