New estimate of galaxies in the observable universe

Catastrophe

"Science begets knowledge, opinion ignorance.
News:

I have just seen program on UK TV in the last hour, containing the estimate of galaxies in the observable universe as 2 trillion (galaxies).

Just to remind you, In the U.S., one trillion is written as the number "1" followed by 12 zeros (1,000,000,000,000).
That gives around 2,000,000,000,000 galaxies only in the observable universe.

Now, how many stars per galaxy?
"Averaging out the types of stars within our galaxy, this would produce an answer of about 100 billion stars in the galaxy. This is subject to change, however, depending on how many stars are bigger and smaller than our own sun. Also, other estimates say the Milky Way could have 200 billion stars or more."
Source: How many stars are in the universe? | Space

Just take, say, 100 billion stars per galaxy. (100,000,000,000 or 10^11)
Than gives 1 x 10^12 multiplies by 10^11 or 10^23 stars in the observable universe.
For those who do not like scientific notation, that is:
200,000,000,000,000,000,000,000 stars.

And some might have you believe that life got started only on this puny backwater of only what we can see of the Universe.

Isn't this just a teeny bit anthropocentric, and perhaps medieval is an adequate description?

Cat :)
 
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"and perhaps medieval"

I prefer the medieval approach, necessary demonstration in nature required to show that Earth is moving around the Sun, not just Copernicus model. Cat, you know me well so you and I do not agree here :) From my thinking, whether one exoplanet, one galaxy, or 10^5000 does not matter. Necessary demonstration in nature is required here, that is indeed *medieval* thinking :)
 

Catastrophe

"Science begets knowledge, opinion ignorance.
Rod, yes, I think that we understand each other.

My only concern is that we discuss any scientific matters here, on a scientific basis. This is, after all, a science based forum.

Do you know of any other medium which permits more philosophical discussion? (Said with all due respect to the rules of this forum). Failing that, I will be happy to conduct a 'one to one' correspondence 'elsewhere', though I believe that we are both entrenched in our assumptions. Mine are scientific, yours are philosophical, and I respect your right to believe whatever you wish. The question is, where is it appropriate to discuss them?

My whole point here, is that no one can prove or disprove Universe-wide abiogenesis. Our proof that abiogenesis has occurred is the fact that we are discussing it here and now. That is my overwhelming item of proof.

That is more proof for the case of abiogenesis than there is for the big bang, or SR or GR or Newton's Laws, because it has occurred (or the results of it have occurred)(vide panspermia) here on planet Earth, as evidenced by the millions of species around us today, and by countless more millions of species which are no longer extant.

The subject of this discussion is framed by:
New estimate of galaxies in the observable universe

Perhaps we had better leave abiogenesis aside, and keep more to topic.
For those who do not like scientific notation, there are approximately 200,000,000,000,000,000,000,000 stars in the observable universe (small 'u') - why don't we leave it to members to draw their own conclusions? This is no place to discuss our personal views.

Cat :) :) :)
 
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The subject of this discussion is framed by:
New estimate of galaxies in the observable universe

Perhaps we had better leave abiogenesis aside, and keep more to topic.
For those who do not like scientific notation, there are approximately 200,000,000,000,000,000,000,000 stars in the observable universe (small 'u') - why don't we leave it to members to draw their own conclusions? This is no place to discuss our personal views.
I get a similar result but I look at it a little differently.

The 2 trillion number I first found from a UT paper that used lensing and they were able to cancel the foreground galactic clusters to reveal the number of these (redshifted) distant galaxies per unit area. Extrapolating this with all galaxies gave them their approximation of 2 trillion in the number of galaxies. There was another paper somewhere that came to that result but using a different method, IIRC.

But, the more distant galaxies seen probably didn't include the smaller dwarf galaxies, which were far more numerous. Yet, on the other hand, the early galaxies had fewer stars than today's galaxies, no doubt.

Here's my calculation, and I compare it to the number of sands on the beach surfaces (ignoring deserts, etc.):

 
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Catastrophe

"Science begets knowledge, opinion ignorance.
From trillion up, I think it is mostly based on the French, hence:
million, billion, trillion, quadrillion, quintillion, sextillion, septillion, octillion, nonillion . . . . . . . . .
Note the double ll = very non-American ;)


mille being 1000, billion? trois quatre, cinq, six, sept, . . . . . .

Cat :)


 
From trillion up, I think it is mostly based on the French, hence:
million, billion, trillion, quadrillion, quintillion, sextillion, septillion, octillion, nonillion . . . . . . . . .
Note the double ll = very non-American ;)


mille being 1000, billion? trois quatre, cinq, six, sept, . . . . . .

Cat :)


:) The problem is million, billion, trillion are all two-syllable words, and quadrillion is three. Government's will have a harder time spending a three-syllable amount of money, so I hope we can control the verbiage before they mess it up. ;)
 
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Catastrophe

"Science begets knowledge, opinion ignorance.
New estimate of galaxies in the observable universe

Well, I think we are agreed that it is quite a lot. Judging by sheer numbers, I do not have the slightest doubt that vast numbers of microbial level life forms exist throughout the Universe, let alone only the observable universe.

As far as 'intelligent' life is concerned, I am sure that it exists, albeit in smaller numbers. Would it not be the height of the height of anthropocentric pride to think that we are the only species to develop enough intelligence to destroy ourselves?

Cat :)
 
Would it not be the height of the height of anthropocentric pride to think that we are the only species to develop enough intelligence to destroy ourselves?
Yes. We, for the first time in history, can extrapolate both the no. of stars in the universe and the no. of exoplanets. So science is giving us reason to hope for life. [This will help direct both philosophy and religion, though not with full concordance with all.]
 

Catastrophe

"Science begets knowledge, opinion ignorance.
I don't think either of us want to go into that area. It is just a matter of personal preference. Anyone seeing the data, which we don't contest, can make up their own minds either way. I am content with that.

Cat :) :) :)
 

Catastrophe

"Science begets knowledge, opinion ignorance.
LG, I recently came across this in a recent book, and thought of you:

"The total mass of the Milky Way has been determined in 2019 from Gaia satellite measurements of millions of stars and star clusters to be 1.5 trillion times the mass of our Sun within one million light years of the centre of the Milky Way. Only about 200 billion solar masses of this total is in the form of stars and interstellar gas clouds. The rest is in a form called Dark Matter"

Cat :)
 
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If all this matter is expressed as energy (E = m*c*c), the event or singularity we call BB may be dimensioned (if one can mentally figure out the magnitude of such "concentration" of energy suddenly released). In an eternal and infinite Universe, the chances for such singularity occurence are ... 100% Then, the BB is the origin of the Cosmos, which is expanding within the Universe, that was always "there", limitedless.
 

Catastrophe

"Science begets knowledge, opinion ignorance.
I think that all these estimates are based on assumptions of one sort or another. We really do not know what 'physics' was like just after t = 0 and before BB. We really do not have the faintest idea what 'physics' is like beyond the observable universe (small u).

It may well be exactly the same as in this puny little backwater, which, after all, is at the very centre of the observable universe, like everywhere else.

Cat :)
 
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I could not agree more with you. Your ideas enhance my "personal cosmology": one unlimited and eternal Universe, with a "small" Cosmos resulting from the Big Bang. Let me go a step further: ¿Which other concept of similar characteristics (unlimited, eternal) has developed in Homo sapiens mind?: Bingo: God. Thus to me the Universe is God and God is the Universe. (I do not profess any religion, but I am a believer).
 

Catastrophe

"Science begets knowledge, opinion ignorance.
Call it what you will here (I am being very careful, so don't put words in my mouth) But I do not believe in the supremacy of old men with beards. There, make of it what you will, but I only said "old men with beards".

The weather here in England is fine and bright, and we are looking forward to two days of celebration of the 70 year record reign of our Queen. Nice change of subject ;) ;) ;) Cat :)
 

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