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 Just a new thought 
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Unread post Re: Just a new thought
you guys are mixing up three or four different things in astronomy...

the "light we see is teh gases on the edge of the event horizion of the black hole being superheated as tehy are sucked in" has little to do with our galaxy. while there is what is called a "complex radio source" at the center of the galaxy, it is nowhere near as powerful as what are called AGNs (active galactic nuclei). in some galaxies, so much matter is falling into the black hole in the middle with such speed that a MASSIVE amount of radiation is emitted. this simply is not the case for the milky way.

right now the best hypothesis states that there is likely a supermassive black hole at the extreme center of our galaxy, just as there is likely a black hole at the center of every galaxy. what I was taking issue with is the fact that in the drawing above, a significant number of the stars in the galaxy are ignored.

also, are you talking about human life? perhaps you could make the argument that humans wouldn't fare too well VERY CLOSE to the black hole, but that doesn't write off the possibility of life all together. we don't even know how to define life on OUR planet, much less for the whole galaxy.

not to mention the fact, as was pointed out a few posts up, that 343 said the effective range was 3 radii.

edit: what i think some of you are referring to is something called the "galactic habitable zone". ignoring the fact that this is a highly controversial concept to begin with (mostly because we have no idea what are the absolute minimum requirements for life), the zone has only a little to with radiation. the zone has more to do with the distribution of heavy elements, which are required for life on EARTH (so we assume they are required for life in general). in fact, the closer a star is to the center of a galaxy, the higher the concentration of heavy elements (due to the life-cycles of stars, etc).
while the concept states that we must be relatively far from the center of the galaxy due to radiation, the radiation is not entirely from the black hole. it is also from supernova, which i study at school, which go off in a given galaxy of our size about once or twice a century (we haven't had one go off in the milky way since 1604, and trust me, if one went off, you'd see it). anyway, it is silly to say that life can't exist in the center of the galaxy, we can't say that for sure.


Last edited by scapermoya on Wed Jul 18, 2007 11:24 pm, edited 1 time in total.



Wed Jul 18, 2007 11:11 pm
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Unread post Re: Just a new thought
*i just got owned*


Wed Jul 18, 2007 11:19 pm
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Unread post Re: Just a new thought
The flood are NOTHING LIKE anything we know of in reality or in the halo universe. Some of the stuff we see in reality is very, very weird, but the most universal quality is that it is incredibly persistent. There are types of bacteria that live in nuclear reactors eating radioactive waste, that live in water just short of boiling, and even types that can survive indefinitely in space (during an Apollo mission, the astronauts examined one of the unmanned craft that had been sent 3 years previously. There were still bactera living on it, exposed to vacuum). And about the supernovae, the most recent that was VISIBLE TO THE NAKED EYE was sighted in 1604 (another visible to the naked eye was seen in 1987, but it was in the Greater Magellanic Cloud). However, supernovae are sighted now at a rate of several per month using computerized telscopes. And we don't know whether any have gone off in a large section of the galaxy-the bulge in the middle makes it impossible to see.


Thu Jul 19, 2007 2:16 am
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Unread post Re: Just a new thought
The flood are NOTHING LIKE anything we know of in reality or in the halo universe. Some of the stuff we see in reality is very, very weird, but the most universal quality is that it is incredibly persistent. There are types of bacteria that live in nuclear reactors eating radioactive waste, that live in water just short of boiling, and even types that can survive indefinitely in space (during an Apollo mission, the astronauts examined one of the unmanned craft that had been sent 3 years previously. There were still bactera living on it, exposed to vacuum). And about the supernovae, the most recent that was VISIBLE TO THE NAKED EYE was sighted in 1604 (another visible to the naked eye was seen in 1987, but it was in the Greater Magellanic Cloud). However, supernovae are sighted now at a rate of several per month using computerized telscopes. And we don't know whether any have gone off in a large section of the galaxy-the bulge in the center makes it impossible to see.


Thu Jul 19, 2007 2:16 am
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Unread post Re: Just a new thought
Sorry about the double post.


Thu Jul 19, 2007 2:17 am
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Unread post Re: Just a new thought
Anyone stop to think that "three radii of the galactic center" means three times the radius of the galactic center rather than three times the radius of the galaxy?


Thu Jul 19, 2007 2:45 am
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Unread post Re: Just a new thought
Quote:
They, and all additional sentient life in three radii of the galactic center, died ...as planned.


I understood the 'in' there as 'within', but I could be wrong.

edit: uncle, you can delete double posts by clicking 'edit' in the upper-right corner of your message, and then checking 'delete post'.

I mentioned "keppler's supernova (1604)" in my post above. it is the last one known to go off in our galaxy. while a supernova on the 'far side' of the milky way may be visible to the naked eye, it would likely be detected. we have several neutrino detectors on the planet running basically full-time which would almost certainly pick up something from a local supernova. also, it is likely that we would see the explosion in the hard-xray (and higher) part of the spectrum. keep in mind that the milky way is relatively thick, and only a thin disk is extremely occulted right through the middle.

also just remembered that we have only had these tools in the last 30 years or so, and some even less than that. a supernova on the far side of the galaxy could have been missed between 1604 and the 1970s (or later).

just so you know, I am heavily involved with KAIT, one of those "computerized telescope" projects that you mentioned. You should know that there is quite a lot of human involvement in finding these extra-galactic supernova, the computers just give us 'candidates'.


Thu Jul 19, 2007 5:32 am
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Unread post Re: Just a new thought
Three radii of the center of the Milky Way Galaxy (Our galaxy :P) is a bit open ended, what classifies as the "center" of our galaxy?
My interpretation of what three radii of the galactic center of the Milky Way would look like:
Image
Original image located at:
http://www.wwu.edu/depts/skywise/a101/milkyway.jpg

If 343 Guilty Spark meant radii as in from the edge of our Galaxy to the center, well, I'm way off.

EDIT:
Forgive my awesome MS paint skillz, I haven't gotten around to putting any better image editing programs on my computer yet, as I just reinstalled windows.


Thu Jul 19, 2007 11:05 am
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Unread post Re: Just a new thought
as shown above, it really makes no sense to interpret it as "three radii of the 'galactic center'". depending on your definition of "galactic center", it may not even include earth, which is just silly.

it really must be three 'galactic radii" from the center.


Thu Jul 19, 2007 3:26 pm
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Unread post Re: Just a new thought
Kriss wrote:
Doesn't add up with the first info GS gave us then...
Maybe GS hasn't told us the hole story... again.


You need to read GS comments again, he says "this installations range" is 25,000 light years.

The Halo's combinded into an array may be far greater then 25,000 light years.

If they only have a range of 25,000 light years you only need to take one down and the point of the weapon is useless as a large amount of the galaxy will survive.


Thu Jul 19, 2007 3:45 pm
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