Anonymous
Anonymous asked in Science & MathematicsAstronomy & Space · 9 months ago

# How did the Crab Nebula get to be 5.5 light years in radius if its supernova explosion only happened 1000 years ago?

You know, because matter can't travel the speed of light. Something seems fishy here...

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• There's nothing fishy unless the nebula is in Pisces.

It's had 1000 years to travel 5.5 light years radius. So in 1 year the debris travels at 5.5/1000 light years per year =0.0055 light years per year.

In miles this is: 5.5 x 6000000000000 / 1000 miles per year = 5.5 x 6000000000 = 3.3 x 10^10 miles per year. (1 light year is 6000000000000 miles).

This is 3.3 x 10^10 / 31557600 miles per second = 1045.7 miles per second. (There are 31557600 seconds in a year, the speed of light is 186000 miles per second).

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• You can't figure out that 5.5 Light Years in 1,000 years is an expansion rate of less than six one-thousandths of a Light Year per year? That is less than six one-thousandths of the speed of light.

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• guys above answered it,it was a mega explosion,debris which is still KKKs of degrees hot,,heavy masssive chunks plus gases,thrown out at a few percent of lightspeed,,chinese astronomers observed it in 1354,,it lit up the earth night sky like daylight.

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• Because the explosion was *very* energetic - sending debris out much faster than we're able to send probes (like Voyager).

186,282 x 60 x 60 x 16.5 = 11,065,150,800 miles, and it's taken 42 years to get there. That's about 263,455,971 miles per yer.

5.5 light years is about 32,332,370,637,600 miles, so the Crab Nebula's outer shell of debris is moving about 32,332,370,637 miles per year.

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• There's no problem there. The image we see of the Crab Nebula is of it roughly a thousand years after it exploded, and 5.5 light years is a distance which can be travelled at a small fraction of the speed of light, namely around 0.5%.

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• light travels 1000 light years in 1000 years, and 1000 is much greater than 5.5. what seems so fishy?

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• We are seeing the effects of its Radiation that does have Light Speed

There is ample time for it to affect the surrounding Matter for at least 1, 000 Light Years across

There are stellar Nurseries among the clouds • Login to reply the answers
• Matter can travel CLOSE to the speed of light. And if the explosion was 1000 years ago how come it is not bigger than 5.5 light years across? Even if the matter moved at 1% the speed of light the nebula should be 10 light years across.

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