APOD: M1: The Incredible Expanding Crab (2013 Sep 05)

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APOD Robot
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APOD: M1: The Incredible Expanding Crab (2013 Sep 05)

Post by APOD Robot » Thu Sep 05, 2013 12:28 pm

Image M1: The Incredible Expanding Crab

Explanation: The Crab Nebula is cataloged as M1, the first on Charles Messier's famous list of things which are not comets. In fact, the Crab is now known to be a supernova remnant, an expanding cloud of debris from the explosion of a massive star. The violent birth of the Crab was witnessed by astronomers in the year 1054. Roughly 10 light-years across today, the nebula is still expanding at a rate of over 1,000 kilometers per second. Want to watch the Crab Nebula expand? Check out this video (vimeo) animation comparing an image of M1 taken in 1999 at the European Southern Observatory, with this one, taken in 2012 at the Mt. Lemmon Sky Center. Background stars were used to register the two images. The Crab Nebula lies about 6,500 light-years away in the constellation Taurus.

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geckzilla
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Re: APOD: M1: The Incredible Expanding Crab (2013 Sep 05)

Post by geckzilla » Thu Sep 05, 2013 3:11 pm

Finally posted it. Slacker! (There was a slight mishap with today's APOD. Thankfully, it's here now.)
Just call me "geck" because "zilla" is like a last name.

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Re: APOD: M1: The Incredible Expanding Crab (2013 Sep 05)

Post by orin stepanek » Thu Sep 05, 2013 3:20 pm

Definately not a comet! Amazing how much it has spread in 14 years! 8-)
Orin

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Re: APOD: M1: The Incredible Expanding Crab (2013 Sep 05)

Post by Ron-Astro Pharmacist » Thu Sep 05, 2013 4:25 pm

Just think - the very first 4th of July fireworks. And probably the biggest ever and still going. :D Maybe we were destined to be free and independent on that date!!! Hope the rest of the countries get a really good celestial event to mark their day to celebrate too. (Soon and without any more innocents lost) :cry:

A really good comet would be nice :wink:
Make Mars not Wars

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Re: APOD: M1: The Incredible Expanding Crab (2013 Sep 05)

Post by Jim Armstrong » Thu Sep 05, 2013 4:28 pm

Still getting over the NSFW APOD from Spain.
What am I missing if the Crab Nebula is 6500 light years away but was caused by a nova 1000 years ago?
Shouldn't we have to wait another 5500 years?

Jim Armstrong

Re: APOD: M1: The Incredible Expanding Crab (2013 Sep 05)

Post by Jim Armstrong » Thu Sep 05, 2013 4:30 pm

Whoops! I see the cause of my misunderstanding.

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Re: APOD: M1: The Incredible Expanding Crab (2013 Sep 05)

Post by MarkBour » Thu Sep 05, 2013 4:37 pm

Yes, Jim Armstrong, you are correct in stating the problem. But the conclusion is a little different:
Since we saw it explode in 1054, and it is 6500 light years away, the actual explosion occurred around 5500 years B.C.
Everything we are now watching when we look at it is a 6500-year-old image as it reaches us.

I wonder what other stars have already exploded, but we are finally going to find out about that in the near future?

Strangerbarry

Re: APOD: M1: The Incredible Expanding Crab (2013 Sep 05)

Post by Strangerbarry » Thu Sep 05, 2013 4:48 pm

Would have been an amazing thing to see back in 1054 - apparently it was so bright you could see it during the day. Would be nice if something like that occured in our own lifetime, may be Eta Carinae ?

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Re: APOD: M1: The Incredible Expanding Crab (2013 Sep 05)

Post by BMAONE23 » Thu Sep 05, 2013 5:10 pm

If it exploded (almost) 1000 years ago and now is 10ly accross today, then it's readios is roughly 5ly and it is expanding at a rate of .005C (1/2% light speed) datsa fast

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Re: APOD: M1: The Incredible Expanding Crab (2013 Sep 05)

Post by Psnarf » Thu Sep 05, 2013 6:11 pm

A thousand kilometers per second?!
Took a minute or two to get over that movie. The pulsating nebula resembles a beating heart. Had to stop it in the middle. I must have read one too many Edgar Allen Poe stories in my youth. "The Tell-Tale Nebula."

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Re: APOD: M1: The Incredible Expanding Crab (2013 Sep 05)

Post by Boomer12k » Thu Sep 05, 2013 7:16 pm

Then why are there parts of the animation that do not show any expansion? Was the new image taken with the same filters as the old image? Because some things appear at the same place others disappear when they should be farther out...at the bottom left it even "shrinks" back...

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sdflyguy

Re: APOD: M1: The Incredible Expanding Crab (2013 Sep 05)

Post by sdflyguy » Thu Sep 05, 2013 7:40 pm

Perhaps a stupid question - - Are there images of M1 availoable from say 1800? 1850, 1900, 1950. They would certainly enhance the "video" :shock: although it was impressive using just 2 images. sdflyguy

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Re: APOD: M1: The Incredible Expanding Crab (2013 Sep 05)

Post by stephen63 » Thu Sep 05, 2013 7:55 pm

Boomer12k wrote:Then why are there parts of the animation that do not show any expansion? Was the new image taken with the same filters as the old image? Because some things appear at the same place others disappear when they should be farther out...at the bottom left it even "shrinks" back...

:---[===] *
The ESO used the FORS2 instrument with an SII filter mapped to red and the red filter mapped to green, didn't use a green filter at all, and a blue filter mapped to blue.
The Schulman Telescope used an Ha, red, green, and blue filter. Pretty impressive, considering how much the FORS2 instrument probably cost.

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Re: APOD: M1: The Incredible Expanding Crab (2013 Sep 05)

Post by Ann » Fri Sep 06, 2013 12:16 am

Congratulations on a new APOD, Adam! :D

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PacRim Jim

Re: APOD: M1: The Incredible Expanding Crab (2013 Sep 05)

Post by PacRim Jim » Fri Sep 06, 2013 4:02 am

Looks more like a kidney.