Spiral Galaxy M83 (APOD 19 Apr 1997)

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harry
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Spiral Galaxy M83 (APOD 19 Apr 1997)

Post by harry » Sat Apr 14, 2007 9:44 am

Hello All


Spiral Galaxy M83

http://antwrp.gsfc.nasa.gov/apod/ap970419.html

Why has this galaxy got more supernova than any other?
Harry : Smile and live another day.

astro_uk
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Post by astro_uk » Sat Apr 14, 2007 11:20 am

It depends on whether they are type 1a or type 2 supernovae, but probably its a combination of having a high star formation rate and the fact that it is relatively nearby and observed regularly so we tend to see more of them.

harry
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Post by harry » Sat Apr 14, 2007 10:13 pm

Hello All

By looking at galaxies we may find the different stages of evolution.

As stars go through their stages of shedding their solar envelope.
Harry : Smile and live another day.

gregg07
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Re: Spiral Galaxy M83

Post by gregg07 » Mon Apr 16, 2007 6:56 pm

harry wrote:Hello All


Spiral Galaxy M83

http://antwrp.gsfc.nasa.gov/apod/ap970419.html

Why has this galaxy got more supernova than any other?
Well... somebody has got to.

harry
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Post by harry » Fri Apr 20, 2007 8:37 am

Hello preggo

Smile,,,,,,,,,,,,,,thats correct.

But! why?
Harry : Smile and live another day.

makc
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Post by makc » Mon Apr 23, 2007 1:43 pm

what he's saying is that it is because of unequal number of supernovas per galaxy. two options, basically, either 1) all galaxies in the universe have the same number of these stars, or 2) there are galaxies with different number of these stars, and in case 2), which by all means is more probable, there have to be galaxies with more supernovas than in others (because otherwise it would be necessary case 1).

it's like why Joe Brower Minnoch was heavier than me and you. because people all possess different body mass, somebody has to weight more than others, and that just happened to be poor Joe.

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NoelC
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Post by NoelC » Wed Apr 25, 2007 1:26 pm

In two galaxies, each with, say, a star population of tens of billions, seeing something happen frequently in one and infrequently in the other implies there is a significantly higher statistical probability of it occurring in the one. The sample size (number of stars) is simply huge, making us fairly confident in that implication. Ergo something's different in M83.

Or am I remembering my college statistics incorrectly?

The discussion tidbit Harry may be looking for is to question the age of M83. Is it older than other spiral galaxies?

Perhaps it is just that statistically things happen in clumps and M83 just happens to have had a few more supernovae than others (e.g., as per the last several posts above).

Galaxies are not all of uniform size... Does M83 contain more stars than other galaxies?

Or is radiation from the increased count of supernovae helping spark others? Or maybe radiation from some past cataclysmic event? I wonder if anyone's mapped out the SN locations and whether they're happening at ever increasing distances from some point.

Could there be a space-time warp because of a particularly large black hole in M83, causing time to pass at a different rate there?

Perhaps more warp-drive ships are traversing M83, altering the laws of physics locally. ;)

-Noel

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