"And pray that there's intelligent life somewhere out in space, 'cause there's bugger all down here on Earth."

FTFA:
"Dr Boss has estimated that each Sun-like star has on average one 'Earth-like' planet.
This simple calculation means there would be huge numbers capable of supporting life."

That article has no depth whatsoever.
Just because one guy plugs random and unsupported (at least by the article) numbers into a subset of the Drake Equation^, doesn't make it so.
If you aren't going to provide detail, you might as well just say it's true because The Bibble says so...which makes one an utter failure as a science reporter.

It's a great big universe
And we're all really puny
We're just tiny little specks
About the size of Mickey Rooney.
It's big and black and inky
And we are small and dinky
It's a big universe and we're not.

Can I have your liver, then?

I think it is extremely reasonable and indeed 99% probably that there are billions of rocky planets that a crudely the size of the Earth and at about the right distance to have bodies of liquid water on them. Our knowledge has made this a very hard conclusion to avoid.

If this is what you call "earthlike" then fine. But I think I would like a tad more. If the planet has no life or has life but has an atmosphere unbreathable by humans is it "earthlike"?

Earth's atmosphere's oxygen was generated by photosynthesis from living cells. Without life, we can be fairly sure because of simple chemistry that there will be no significant oxygen in the atmosphere. We don't know how life started and thus have no clue just how likely it is. That life started reasonably early in Earth history might be a clue or it might have been luck. From there we don't know how likely it is that oxygen generating photosynthesis would have evolved. Maybe there is some process that would do the job for like that will put oxygen in the atmosphere.

And I might point out that for much of Earth's own history, it was hardly like the globe we know and love today. It took photosynthesis a long time to generate enough oxygen to rust out the iron around before the atmosphere could start getting significant oxygen. Indeed less than half Earth's history could you have survived on its surface without an oxygen mask.

And consider that land vertebrates existed for less than 10% of Earth history. And indeed land plants of any size are less than 500 million years old. (Earth is 4.55 billion years old.) If you landed on the dry land 500 million years ago you would have seen a barren landscape with at most very simple life forms though you could have breathed the atmosphere.

they're not going to find life out there.

you heard it here first.

Funny, I had this exact thought at the age of 8.

None of these possibly inhabited worlds are within a distance of one-half the rest of my natural life or less at the speed of light, so who cares?

No need to play it safe. If there is bacteria, there is probably complex, macroscopic life as well. The bottleneck is abiogenesis. Once simple, self-replicating molecules take over a planet's potential energy pellets, evolution becomes a runaway train and a foregone conclusion. It seems reasonable to believe that a planet similar to our own would have a similar level of development at a similar age.

Talon: It's a great big universe
And we're all really puny
We're just tiny little specks
About the size of Mickey Rooney.
It's big and black and inky
And we are small and dinky
It's a big universe and we're not.

Gratuitous, "Hello, Nurse!"



//dotlinked
///see what I did?

Bevets: There are indeed a lot of stars -- at least ten billion billion in the observable universe. But this number, gigantic as it may appear to us, is nevertheless trivially small compared with the gigantic odds against the random assembly of even a single protein molecule. ~ Paul Davies

Whatever your opinion of Him, it should be acknowledged that Jesus has had a more significant impact on history than any other person. Many people would agree that Jesus was a good moral teacher, but Jesus claimed to be God. .. He must have been either profoundly deluded or dishonest. Either of these possibilities would disqualify him as a moral leader, however He established a loyal following that has persisted for two millennia
bevets.com

VS



There's an argument that because as a civilization advances it puts out more power, we are either utterly alone or civilizations stop broadcasting information at a certain point. We would have seen them early in radio astronomy.

This point is where they kill themselves or find something better. I'm hoping we stumble upon the equivalent of AM broadcasts in some FTL transmission and we find it's in use.

/Knowing my luck it'll be religious programming.
//Visualize Mormon missionaries riding their bikes in pressure suits on the moon.

Bevets: There are indeed a lot of stars -- at least ten billion billion in the observable universe. But this number, gigantic as it may appear to us, is nevertheless trivially small compared with the gigantic odds against the random assembly of even a single protein molecule. ~ Paul Davies

Luckily, scientists don't think propose that life need to completely randomly assemble a very specific protein. If they did you would have a point instead of yet again engaging in dishonest quote mining.

Maybe I will quote something (new window) you won't:

Similarly, of the 1 × 10¹³⁰ possible 100 unit proteins, 3.8 × 10⁶¹ represent cytochrome C alone! [29]

[29] Yockey HP, On the information content of cytochrome c. J Theor Biol, 67: 345-76, 1977

Of course Yockey is a common target of quote miners as if his work should give creationism any comfort.

By strange coincidence in a book I found in the library today (one by leading physicist Leonard Susskind):

Number of protons and neutrons in Earth (approximately) = 5 × 10⁵¹

The number of cytochrome Cs for 100 amino acid long proteins is around ten billion times larger than the number of protons and neutrons that make up our entire planet.

Now random assembly of just one of those sequences can take many millions of years over an entire planet. And of course, the process might not be completely random -- indeed I would be surprised if it was.

But heck, I am not convinced that life simply MUST have cytochrome C.

This should give the lie (or at least utter incompetence) of creationist calculations that random assembly of a single protein sequence is utterly impossible: not because it is possible, but because that is not what scientists propose.

I was told there would be no math

colon_pow: they're not going to find life out there.

you heard it here first.

Do you really think that this planet is the only planet in the entire, mind-bogglingly HUGE universe (or even our own galaxy) to have some kind of life?

Tommy Moo: No need to play it safe. If there is bacteria, there is probably complex, macroscopic life as well. The bottleneck is abiogenesis. Once simple, self-replicating molecules take over a planet's potential energy pellets, evolution becomes a runaway train and a foregone conclusion. It seems reasonable to believe that a planet similar to our own would have a similar level of development at a similar age.

I added some emphasis to a keyword.

Of course bacteria should be in quotes as well. They won't be the same as our bacteria.

But I don't see how you conclude that "bacteria" implies some kind of intelligent life. Do you realize just most of history of life was limited to life that not multicellular in a way most would use the word. That most of the history of life, life was pretty much stuck in the ocean. Indeed land vertebrates have existed for about 10% of the history of life (give or take a lot).

There are many dangers too. Too much asteroid impacts or other disasters could stop the evolution of intelligent life. Gamma-ray bursters could end life on a planet.

And even if intelligent life evolves, there is no guarantee it will be able to develop advanced technology. Dolphins no matter how bright could not do it -- they lack appropriate limbs and live in water. It is not a sure thing that every planet will have appropriate natural resources.

There just so many factors. We really don't know what the bottlenecks really are. It is very possible that abiogenesis is easy and complex "animals" are not especially given how fast life appeared and how long it took for animals to appear.

LordJiro: Do you really think that this planet is the only planet in the entire, mind-bogglingly HUGE universe (or even our own galaxy) to have some kind of life?

I would put the universe at pretty much 0% especially given modern cosmological theory makes the universe at least 150 billion light years wide. (And it is still possible that it is infinite -- which is a possibility with inflationary big bang theory. If that is the case the possibility that earth is the only planet with life is precisely zero.) Heck, even within the Hubble volume of 13.7 billion light years radius, I would assume that there are many planets with life.

But our own galaxy is a different matter. We don't know the cause of abiogenesis and thus really can't estimate how likely life really is. It is not out of the realm of possibility that life is unlikely enough that our planet is the only one in the Galaxy with life. I suspect that other planets in our Galaxy do have life of some sort. Then come a bunch of other questions like how likely that complex cells (like our eukaryotic cells) will evolve, how likely that large multicellular life will evolve, how likely is it that intelligence will evolve, how likely is a technological civilization, how long with the civilization last, how likely is it that we could detect them, etc. All of these are completely unanswered questions.

TheMysteriousStranger: The number of cytochrome Cs for 100 amino acid long proteins is around ten billion times larger than the number of protons and neutrons that make up our entire planet.

Now random assembly of just one of those sequences can take many millions of years over an entire planet. And of course, the process might not be completely random -- indeed I would be surprised if it was.

But heck, I am not convinced that life simply MUST have cytochrome C.

This should give the lie (or at least utter incompetence) of creationist calculations that random assembly of a single protein sequence is utterly impossible: not because it is possible, but because that is not what scientists propose.

This reminded me of a quote from a book I read recently (Bill Bryson's A Short History of Nearly Everything, aka Science for Morans) discussing the Big Bang - that although it might be extremely unlikely for an entire universe to be created, that nobody had ever counted the failed attempts. That is, there could have been trillions and trillions of Big Bangs, and the only reason we exist in this one is because this is the only one we could exist in.

t3knomanser: Tsunami Ditka: the only reason we exist in this one is because this is the only one we could exist in.

Also known as the weak anthropic principle.

Some people look at the universe and say, "Man, if all these things were a little bit different, the universe as we see it would be impossible. It must be made for us!" That's the strong anthropic principle.

Other people look at the universe and say, "Man, if all these things were a little bit different, we wouldn't be here to notice them. Can't really draw any conclusions from that." That's the weak anthropic principle.

Whaddya know. I figured there was a name for it!

Call me when we get there.

I'm going to be figuring out some other things in the meantime.

/goes back to calculating UFT, playing CivIV, paying bills or jackin' off...which ever catches my fancy first...

Said this decades ago. Way to catch up.

Inigo_Montoya: I was told there would be no math

Yeah, well, I killed your father.

/nicely done subby

maddogdelta: Whatever your opinion of Him, it should be acknowledged that Jesus has had a more significant impact on history than any other person. Many people would agree that Jesus was a good moral teacher, but Jesus claimed to be God. .. He must have been either profoundly deluded or dishonest. Either of these possibilities would disqualify him as a moral leader, however He established a loyal following that has persisted for two millennia
bevets.com


WOW!
I always assumed Bevets was a fundamentalist Christian but judging by this quote you pulled from his website, it's OBVIOUS that he is exactly the opposite!

Bevets: There are indeed a lot of stars -- at least ten billion billion in the observable universe. But this number, gigantic as it may appear to us, is nevertheless trivially small compared with the gigantic odds against the random assembly of even a single protein molecule. ~ Paul Davies

this.

The Universe - (some information to help you live in it.)

Area - Infinite

Infinite : Bigger than the biggest thing ever and then some. Much bigger than that in fact, really amazingly immense, a totally stunning size, real "wow, that's big," time. Infinity is just so big that by comparison, bigness itself looks really titchy. Gigantic multiplied by staggeringly huge is the sort of concept we're trying to get across here.

Imports - none.

It is impossible to import things into an infinite area, there being no outside to import things from.

Exports - none.

See IMPORTS.


Population - none.

It is known that there are an infinite number of worlds, simply because there is an infinite amount of space for them to be in. However, not every one of them is inhabited. Therefore, there must be a finite number of inhabited worlds. Any finite number divided by infinity is as near to nothing as makes no odds, so the average population of all the planets in the Universe can be said to be zero. From this it follows that the population of the whole Universe is also zero, and that any people you may meet from time to time are merely the products of a deranged imagination.

Monetary units - none.

In fact there are three freely convertible currencies in the Galaxy, but none of them count. The Altairian Dollar has recently collapsed, the Flanian Pobble bead is only exchangeable for other Flanian Pobble Beads, and the Triganic Pu has its own very special problems. Its exchange rate of eight Ningis to one Pu is simple enough, but since a Ningi is a rubber coin six thousand eight hundred miles along each side, no one has ever collected enough to own one Pu. Ningis are not negotiable currency, because the Galactibanks refuse to deal in fiddling small change. From this basic premise it is very simple to prove that the Galactibanks are also the product of a deranged imagination.


Art - none.

The function of art is to hold the mirror up to nature, and there simply isn't a mirror big enough - see AREA.


Sex - none.

Well, in fact there is an awful lot of this, largely because of the total lack of money, trade, banks, art or anything else that might keep all the nonexistent people of the Universe occupied.

However, it is not worth embarking on a long discussion of it now because it really is terribly complicated. For further information see GUIDE Chapters seven, nine, ten, eleven, fourteen, sixteen, seventeen, nineteen, twenty-one to eighty-four inclusive, and in fact most of the rest of the Guide.

Just remember that you're standing on a planet that's evolving
And revolving at nine hundred miles an hour,
That's orbiting at nineteen miles a second, so it's reckoned,
A sun that is the source of all our power.
The sun and you and me and all the stars that we can see
Are moving at a million miles a day...

When the end comes, I know I'll be just a gigolo
Life goes on without me

t3knomanser: Tsunami Ditka: the only reason we exist in this one is because this is the only one we could exist in.

Also known as the weak anthropic principle.

Some people look at the universe and say, "Man, if all these things were a little bit different, the universe as we see it would be impossible. It must be made for us!" That's the strong anthropic principle.

Other people look at the universe and say, "Man, if all these things were a little bit different, we wouldn't be here to notice them. Can't really draw any conclusions from that." That's the weak anthropic principle.

Working in Data Analysis, I can tell you that this is the problem with having a single data set with which to work. It could be that our universe is just a fluke but, without having other instances to compare to, it's impossible to say.

The same goes with life. I, personally, think it would be extremely unlikely that Earth was the only spot in the universe where life exists but - as of now - it's the only example we have. Earth, or humanity, might have an extremely unlikely combination of factors that allowed life (or intelligent life) to evolve.

And if we're going to sing space songs, don't forget Interplanet Janet (launches like a rocket).

Bevets: There could be one hundred billion Earth-like planets in our galaxy, a US conference has heard.

Dr Alan Boss of the Carnegie Institution of Science said many of these worlds could be inhabited by simple lifeforms...

This simple calculation means there would be huge numbers capable of supporting life.

There are indeed a lot of stars -- at least ten billion billion in the observable universe. But this number, gigantic as it may appear to us, is nevertheless trivially small compared with the gigantic odds against the random assembly of even a single protein molecule. ~ Paul Davies

Within the context of infinity and eternity, "odds" are a meaningless concept.

LordJiro: colon_pow: they're not going to find life out there.

you heard it here first.

Do you really think that this planet is the only planet in the entire, mind-bogglingly HUGE universe (or even our own galaxy) to have some kind of life?

Actually, there is a high probability that he is right. Our species is not going to exist for an infinite length of time, and we will never be able to explore more than a small part of our huge, and possibly infinite universe. Sure, there's life out there - but it's quite probable that we will never encounter it.

jso2897: Actually, there is a high probability that he is right. Our species is not going to exist for an infinite length of time, and we will never be able to explore more than a small part of our huge, and possibly infinite universe. Sure, there's life out there - but it's quite probable that we will never encounter it.

However, are we talking about "just finding life" or finding what we would call "intelligent" life? Because, if it is the former, then we have reasonable odds of finding that life right in our solar system, possibly on Mars or on one of the moons of Jupiter or Saturn.

Beyond that, it gets troublesome, as we might be able to find some indicators (spectral analysis of the atmosphere of extrasolar planets, maybe), but without going there, it would be very difficult to actually tell if there was life there or not.

The big flaw in listening for radio transmissions from other species is this: How do we know they use radio at all? Maybe they found something that works better. Maybe they perceive the electromagnetic spectrum differently. Maybe they never developed radio and skipped straight to ansible communication networks, or some other system that works just as well or better but we are incapable of understanding it because it requires four sensory organs that don't exist in any terrestrial life form?. The presumption that any civilization would mirror out own in technological, biological, or sociological development is complete hubris and gratuitous ego-stoking.

It's cute when they treat "infinity" like a real number instead of a concept.

with all the Billions of planets in the Universe it hard to imagine any of them with life, except earth, of course.



lol

t3knomanser: Tsunami Ditka: the only reason we exist in this one is because this is the only one we could exist in.

Also known as the weak anthropic principle.

Some people look at the universe and say, "Man, if all these things were a little bit different, the universe as we see it would be impossible. It must be made for us!" That's the strong anthropic principle.

Other people look at the universe and say, "Man, if all these things were a little bit different, we wouldn't be here to notice them. Can't really draw any conclusions from that." That's the weak anthropic principle.

Life is the Universe's attempt to understand itself.