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Extraterrestrials Probably Haven't Found Us - Yet

Zonk posted more than 7 years ago | from the hello-up-there dept.

Space 588

kasparn writes "The Guardian today has a story about the Danish astrophysicist Rasmus Bjoerk, who recently conducted simulations on how long it will take to colonize the Milky Way. The basic idea is to send out probes in different directions (including various heights above the galactic plane). He estimates that it will take some 10 billion years to explore 4 % of the Milky Way. Since the age of the Universe is of the same order, his conclusion is that aliens can't have had time required to find us yet."

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Heh (0)

Anonymous Coward | more than 7 years ago | (#17668662)

First research warp drive.
After that...

Re:Heh (2, Interesting)

master_kaos (1027308) | more than 7 years ago | (#17668850)

Exactly, who say Aliens - if they exist - hasn't come up with some vastly superior way of travel (maybe instant teleportation, etc). And even if they do know about our presence, why would they care? There are most likely millions of other planets that are available, why bother fighting over one that has inferior beings on it, that will most likely destroy themselves within the next few centuries. We most likely have nothing of value to them, so what would be the purpose of them "contacting us"

Re:Heh (4, Funny)

pbrammer (526214) | more than 7 years ago | (#17668968)

They want all of our "base"?

Re:Heh (3, Interesting)

yurnotsoeviltwin (891389) | more than 7 years ago | (#17669002)

Also, this simulation was about colonization. It's a lot easier to find something than to colonize it, especially in places that aren't very conducive to supporting life.

Re:Heh (4, Informative)

tha_mink (518151) | more than 7 years ago | (#17669104)

Bitten by the ole RTFA bug eh. The quote from the article is

He found that even if the alien ships could hurtle through space at a tenth of the speed of light, or 30,000km a second, - Nasa's current Cassini mission to Saturn is plodding along at 32km a second - it would take 10bn years, roughly half the age of the universe, to explore just 4% of the galaxy. His study is reported in New Scientist today.

No mention of colonization there.

Plus

Mr Bjork confined the probes to search only solar systems in what is called the "galactic habitable zone" of the Milky Way, where solar systems are close enough to the centre to have the right elements necessary to form rocky, life-sustaining planets, but are far enough out to avoid being struck by asteroids, seared by stars or frazzled by bursts of radiation.

So there's that too. Looks like you should have taken a look at the article first.

Re:Heh (2, Interesting)

foursky (1052628) | more than 7 years ago | (#17669148)

Who's to say that the Aliens arent God, who put us here in the first place? Aliens plant humans here, sit back and watch, checking up on us every so often.

Humans look at 9 planets in a solar system, and not very well mind you, and determine that life in the universe is unlikely? Who's to say that the Milky Way isnt 10% populated (1 habited planetary body per solar system)?

Re:Heh (0)

Anonymous Coward | more than 7 years ago | (#17669296)

Those are some weird ass ideas dude.

Re:Heh (0, Flamebait)

Yr0 (224662) | more than 7 years ago | (#17669150)

Shut up you fucking geek.

COMMENT ON THE ARTICLE, NOT FUCKING SCI-FI shows.

I mean, it's not as if anyone else will say anything about warp drive, it's so original!

Forgot one thing... (1)

Duncan3 (10537) | more than 7 years ago | (#17668676)

Well obviously you would use a TARDIS, which makes it more like 100%.

I should hope so... (5, Funny)

creimer (824291) | more than 7 years ago | (#17668688)

We will be in a lot of trouble if the Cylons find us first.

Re:I should hope so... (3, Informative)

Homr Zodyssey (905161) | more than 7 years ago | (#17668794)

Silly! They aren't aliens. They are man-made robots.

Re:I should hope so... (0)

Anonymous Coward | more than 7 years ago | (#17669210)

In the old series they were made by lizard people.

Re:I should hope so... (1)

SpaceLifeForm (228190) | more than 7 years ago | (#17668858)

Well, it seems the Cylons are already running the U.S. Government, and it would explain the NSA spying.

Actually the cylons will find us first (3, Interesting)

AHumbleOpinion (546848) | more than 7 years ago | (#17669326)

We will be in a lot of trouble if the Cylons find us first.

Actually the "cylons" will find us first, it is far cheaper to send robotic explorers out. Then if anything interesting is found send the "manned" missions.

Uh (0)

Anonymous Coward | more than 7 years ago | (#17668702)

Warp Drives D00d!

That's assuming... (1)

GillBates0 (664202) | more than 7 years ago | (#17668720)

I haven't RTFA (at work) but I'm guessing this is assuming that they haven't developed signals/travel faster than the speed of light.

Re:That's assuming... (0)

Anonymous Coward | more than 7 years ago | (#17668846)

Actually, I think that this is assuming quite a bit. The age/size of the universe, the technologies that different alien life would have available, etc.

Meaning, he is guessing completely and saying that this is how long 'humans' would take to do it.

Re:That's assuming... (1)

IgLou (732042) | more than 7 years ago | (#17668914)

I read some of it and the biggest assumption was that probes would travel at most 1/10 the speed of light.

I think if you're going to go through the trouble of writing a paper like this it would be interesting to consider an FTL scenario as well. Say compare the numbers for 1/10c, c, and 10c. But then again, what would the realistic assumption be on speed?

Based on poor assumptions (4, Insightful)

BadERA (107121) | more than 7 years ago | (#17668728)

Why 1/10th c? Why not 99% of c? Why not faster than c? Granted faster than light travel is nothing more than theory and dreams at this point, but this article makes the assumption that other civilizations have not progressed in the field of physics any faster nor further than we ourselves have, to date.

Re:Based on poor assumptions (5, Insightful)

QuantumG (50515) | more than 7 years ago | (#17668916)

Yeah, imagine a civilization that, having discovered enlightenment, actually embraced it and dedicated their industrial base to further it, instead of shuffling it off to the minor specialists who they then make beg for funding, typically by militarizing their research.

Re:Based on poor assumptions (5, Funny)

BadERA (107121) | more than 7 years ago | (#17669118)

Psssh, enough of that hippie dudley do-right love and flowers attitude, that will get you nowhere in this life.

(That said, I totally agree with you.)

Re:Based on poor assumptions (3, Insightful)

Marlow the Irelander (928776) | more than 7 years ago | (#17669220)

Nasa's current Cassini mission to Saturn is plodding along at 32km a second

c/10 is 30,000km/s. The article makes the assumption that alien civilizations have advanced enough that their spaceships are 1,000 times faster than ours - not unreasonable.

Fine assumptions, poor conclusion (4, Interesting)

dyslexicbunny (940925) | more than 7 years ago | (#17669252)

I agree. He's only basing his assumptions on our current capabilities and applying them to an unknown alien civilization. Great that he's making these assumptions but his final conclusion, We have not yet been contacted by any extraterrestrial civilizations simple because they have not yet had the time to find us. Searching the Galaxy for life is a painstakingly slow process., is just jumping to conclusions, perhaps invalid for the work he did.

No one knows what aliens are going to look for in a planet. Our planet could be written off as an inhabitable nitrous sphere. They might be non-carbon based life forms. They could have progressed technologically much faster than we did as you suggested. By assuming aliens match our capabilities, he made an unstated assumption that was key to actually understanding the conclusion.

A more fitting conclusion from his work would be that it would take US 10 billion years to search a small portion of the Milky Way for life at our current technology levels.

Duh (5, Insightful)

Reality Master 101 (179095) | more than 7 years ago | (#17668738)

Sheesh, talk about "proof by lack of imagination." This is supposed to answer the Fermi Paradox?

You can't explore a galaxy with a handful of probes. 72 probes??? First of all, if you're going to do it that way, you'd create hundreds of thousands of probes, if not millions of probes (mass production would reduce the cost). Second, you still probably wouldn't do it that way. You'd wait until you had the technology to make self-replicating probes, and the galaxy could potentially be explored in thousands of years.

Not impressed by this guy's argument.

Re:Duh (1)

silas_moeckel (234313) | more than 7 years ago | (#17668908)

Funny I thought the galaxy was 100k ish light years across. So it would take half of that if we started at the center and the probes moved at light speed. It would take the same half of that to get the final results back so the minimum time is 100k years, without going faster than light.

Re:Duh (1)

Reality Master 101 (179095) | more than 7 years ago | (#17669018)

Funny I thought the galaxy was 100k ish light years across. So it would take half of that if we started at the center and the probes moved at light speed. It would take the same half of that to get the final results back so the minimum time is 100k years, without going faster than light.

The galaxy is 30,000 light years across. I actually thought of that after I posted, but I figured "thousands" covers everything up to a million. :)

Re:Duh (2, Funny)

Gropo (445879) | more than 7 years ago | (#17668938)

u'd wait until you had the technology to make self-replicating probes, and the galaxy could potentially be explored in thousands of years.
Yes, and let's hope beyond all hope that once the probes arrive they don't require vast amounts of O and/or H2O to replicate themselves. And that they'll recognize Sol 3 as a planet fostering 'advanced' life.

Re:Duh (0)

Anonymous Coward | more than 7 years ago | (#17668946)

"First of all, if you're going to do it that way, you'd create hundreds of thousands of probes, if not millions of probes"

Not if your leader hamstrung the budget of your space agency......

Re:Duh (2, Insightful)

exp(pi*sqrt(163)) (613870) | more than 7 years ago | (#17668976)

You're right, this guy hasn't thought things through. He rejects self-replicating probes because they'd compete with the original explorers. I think that's a lame argument, but let's accept it. Even human colonies spreading out from Earth, and moving onto new stars every generation or two (and sending out some non-self-repicating probes while they're at it), would explore the galaxy far faster than these probes. If humans survive the next century or two I'm sure they'll explore the galaxy in person far faster than this unambitious probe idea.

Re:Duh (4, Informative)

isomeme (177414) | more than 7 years ago | (#17668984)

You'd wait until you had the technology to make self-replicating probes, and the galaxy could potentially be explored in thousands of years.

Bingo. As usual, Wikipedia has a good article [wikipedia.org] on the topic.

Re:Duh (1)

debrain (29228) | more than 7 years ago | (#17669056)

You'd wait until you had the technology to make self-replicating probes

I remember some giant bags of gas in Star Control II who did just that. It was a bad move on their part.

Re:Duh (1)

Darthmalt (775250) | more than 7 years ago | (#17669066)

Plus lets not forget that there is also the possibility that these aliens aren't that far away and got lucky. Or perhaps they aren't dissimilar from us figured out which planets are most likely to have life like theirs and checked those first.

Re:Duh (5, Funny)

myowntrueself (607117) | more than 7 years ago | (#17669114)

You can't explore a galaxy with a handful of probes. 72 probes???
Not impressed by this guy's argument.

He is probably just assuming that the aliens have a pretty much exact parallel to NASA.

Re:Duh (3, Insightful)

Mr. Slippery (47854) | more than 7 years ago | (#17669128)

you'd create hundreds of thousands of probes, if not millions of probes..You'd wait until you had the technology to make self-replicating probes, and the galaxy could potentially be explored in thousands of years.

Uh-huh. And how many self-replicating probes traveling at .1 c have you developed?

The fact that we can imagine self-replicating interstellar probes doesn't mean they are practical or possible.

Re:Duh (1, Interesting)

Reality Master 101 (179095) | more than 7 years ago | (#17669268)

Uh-huh. And how many self-replicating probes traveling at .1 c have you developed?

Hence my use of the phrase, "wait until you had the technology." No one is going to do this until they're so bored with their own solar system that it makes sense to tackle something of this magnitude.

The fact that we can imagine self-replicating interstellar probes doesn't mean they are practical or possible.

You're right, the whole idea of self-replication is clearly impossible.

Re:Duh (3, Insightful)

muellerr1 (868578) | more than 7 years ago | (#17669166)

I tend to agree. Think about it this way: how much of *our* resources are we currently using to explore the entire galaxy? And how much are we likely to in the future? The answer is, not much. It's a vanishingly small return on a huge investment to explore the galaxy, especially when we've got bigger problems at home and so much raw material in our own solar system. The costs of sending crap into deep space will probably outweigh the benefits of mineral riches for far into the future, despite Ridley Scott's imagination. Unless there are aliens within a few hundred light years of us (which at this point is a vanishing probability given that we've found under 200 exoplanets within 200 parsecs [exoplanets.org] ) we won't find any aliens -- and they won't find us, either.

Scary (2, Funny)

SpeedyGonz (771424) | more than 7 years ago | (#17669178)

72 probes??? First of all, if you're going to do it that way, you'd create hundreds of thousands of probes, if not millions of probes (mass production would reduce the cost). Second, you still probably wouldn't do it that way. You'd wait until you had the technology to make self-replicating probes, and the galaxy could potentially be explored in thousands of years.

Hmm . . .

1.- self replicating probes... check
2.- enuff "intelligence" to determine something it sees/feels/etc is an actual lifeform... check
3.- humanity's own history making buggy, security lax software... check
4.- throw in some polymorphic stuff in the software so the probe can better itself...check
5.- an "easter egg", timebomb prank from a bender-obsessed hacker (MUST KILL HUMANS)... check

Possible end result? == The cylons :)

Re:Duh (1)

div_2n (525075) | more than 7 years ago | (#17669212)

I would think any sufficiently intelligent civilization would first develop automated systems to scan for candidate planets. We're working on that now.

Working with a list of candidate planets (as ours surely would be), an alien civilization could be much more efficient in their searching for other forms of intelligent life.

Re:Duh (2, Funny)

turnipsatemybaby (648996) | more than 7 years ago | (#17669300)

Geez, that's a terrible idea! Last time anyone did that, a bumbling race grab a hold of one and reprogrammed it to replicate as its top priority over everything else! The result was that the probes were finding other races and then breaking them down into their component compounds with their lightning thingies!

The Galactic Lottery (5, Funny)

neo (4625) | more than 7 years ago | (#17668750)

Come on. 4% is a hell of a lot better than your odds of winning the lottery and that happens *everyday*.

Plus he's not taking into account multiple alien races. So that's like double 4% which is almost 8%. Do that a few hundred times and you get 108%. This guy clearly doesn't understand math.

Re:The Galactic Lottery (2, Insightful)

solafide (845228) | more than 7 years ago | (#17668870)

Plus he's not taking into account multiple alien races. So that's like double 4% which is almost 8%. Do that a few hundred times and you get 108%. This guy clearly doesn't understand math.
Nope, do that n times and you get 1-(.96)^n probability they find us.

I would hope (0)

Anonymous Coward | more than 7 years ago | (#17668758)

...there was more than one other alien civilization.

Re:I would hope (1)

metlin (258108) | more than 7 years ago | (#17668812)

I would hope ...there was more than one other alien civilization.


Well, yes.

They are called the French and they across the pond.

=)

(Sorry, couldn't resist!)

Re:I would hope (1)

lonechicken (1046406) | more than 7 years ago | (#17669126)

I would hope ...there was more than one other alien civilization.
Well, yes. They are called the French and they across the pond.
One of the great first jokes from Futurama had people from all over the world counting down on New Year's Eve prior to the year 3000, in their own languages. (at the same time for some reason). Even aliens counted down in their language. But the French counted down in English. So in less than a thousand years, they probably won't be so alien to us.

Re:I would hope (1)

metlin (258108) | more than 7 years ago | (#17669298)

Yeah, but they might have had Queen Liz as the French queen [telegraph.co.uk] , too.

Five more minutes... (0)

Colonel_Zoff (1053018) | more than 7 years ago | (#17668762)

Well, they better hurry, those aliens have only five minutes to find us before mankind will be utterly exterminated in a global thermonuclear war! The way I see it, that Doomsday Clock is a terrible risk to all free men!

Good news is: (1)

hsmith (818216) | more than 7 years ago | (#17668772)

Humans will have killed themselves off with war before they have the chance to find us!

Re:Good news is: (1)

phoric (833867) | more than 7 years ago | (#17669072)

You're right. So what're we gonna do about it?

Screw it, lets kill those war-mongering bastards!!

Be Fruitful (0)

Anonymous Coward | more than 7 years ago | (#17668774)

If he isn't right, maybe the aliens have been fucking alot?

I hear they like anal.

Aww (0)

Anonymous Coward | more than 7 years ago | (#17668778)

A major blow to star trek fans.......

Re:Aww (1)

CheeseburgerBrown (553703) | more than 7 years ago | (#17668844)

A major blow to star trek fans...

That's the gist of the wet dreams, yes. Hope will never die.

Wrong, wrong, wrong (4, Interesting)

Ignorant Aardvark (632408) | more than 7 years ago | (#17668784)

This figure of taking billions of years to explore the galaxy is utterly wrong. Actually, it only takes a few dozen million years to colonize the entire damn galaxy, which is a lot more effort than merely exploring it.

This figure is based on some very reasonable assumptions. Colony ships travel at much below the speed of light. Each colony gets a thousand years of development time from first colonization before it starts sending out its own colony ships. As you can see, even though it seems quite "slow", thanks to the magic of exponential growth, the entire galaxy is colonized in short order.

We won't merely be discovered if aliens exist - we'll be colonized. That's the most likely scenario for running into aliens. If they never spread beyond their home planet, they'll just be one star out of trillions - but if they do start colonizing, we'd find them everywhere.

Re:Wrong, wrong, wrong (1)

Broken scope (973885) | more than 7 years ago | (#17668842)

Wouldn't the speed of the ships increase during the thousand years? HEll what is to say we won't find a way around tha pesky speed of light.

Re:Wrong, wrong, wrong (1)

Ignorant Aardvark (632408) | more than 7 years ago | (#17669146)

Wouldn't the speed of the ships increase during the thousand years? HEll what is to say we won't find a way around tha pesky speed of light.
Yes, technology would definitely improve. But I used very low-ball, reasonable estimates in this calculation, which include that the laws of physics as we know them today are correct, and that FTL isn't possible. The point is, even under the most pessimistic of conditions, a civilization that is actively colonizing will cover the entire galaxy on the order of millions of years, not billions.

Re:Wrong, wrong, wrong (1)

Mr. Slippery (47854) | more than 7 years ago | (#17668924)

This figure is based on some very reasonable assumptions. Colony ships travel at much below the speed of light.

You're assuming interstellar colonization as practical. While it's a sci-fi staple, load of fun to imagine, it's quite likely not.

Re:Wrong, wrong, wrong (1)

georgewilliamherbert (211790) | more than 7 years ago | (#17669076)


You're assuming interstellar colonization as practical. While it's a sci-fi staple, load of fun to imagine, it's quite likely not.


The only question about its feasibility is whether we start using energy sources of the appropriate magnitude or not. All the rest is just engineering.

If Humanity stays on Earth and doesn't exploit extraterrestrial resources (space based solar, mining asteroids, the moon, etc) then we probably won't have that magnitude of energy.

If we do expand out, the energy required is pretty trivial to collect, not so trivial to focus and convert to usably driving interstellar spacecraft, but that's just an economics question.

Re:Wrong, wrong, wrong (1)

Ignorant Aardvark (632408) | more than 7 years ago | (#17669100)

This figure is based on some very reasonable assumptions. Colony ships travel at much below the speed of light.

You're assuming interstellar colonization as practical. While it's a sci-fi staple, load of fun to imagine, it's quite likely not.

Why isn't it practical? There's no reason whatsoever that it won't be practical. Just over a hundred years ago they said human flight was impractical too, you know. And look at the airline industry these days. There's a huge difference between FTL, a science fiction staple that is physically impossible as far as we know, and space colonization another science fiction staple that has no physical laws standing in its way. Rockets are a science fiction staple too, you know, but nobody these days is claiming that they are impractical ...

Well.. (1)

Drakin020 (980931) | more than 7 years ago | (#17668786)

Unless the aliens are more productive. They don't have to be built on our level.

Unless they're nearby already (1)

Kelson (129150) | more than 7 years ago | (#17668792)

aliens can't have had time required to find us yet.

So it would take 10 billion years to visit 4% of the Milky Way. In theory, if there are any aliens within the nearest 4% to us, they may have had time to visit us. Realistically, let's say the nearest 2%, to allow time for intelligent life to evolve and develop space travel. 2% of the galaxy is still a pretty big space, though you'd think we'd have seen some evidence of an alien civilization that (relatively) nearby.

Well, DUH! (3, Insightful)

QuantumG (50515) | more than 7 years ago | (#17668796)

To paraphrase: But Sir! If we only send 8 probes it'll take billions of years to search a mere 4% of the Milky Way galaxy!

That's why you have to make the probes self replicating.. utilizing in-situ resources to make more probes at each star they visit, the growth becomes exponential and it only takes a few thousand years to search the entire galaxy. And seeing as we're visiting all these stars anyway, how about looking for planets that don't have life on them, but have nice suitable conditions for starting life on them. Cover a virgin planet with a wide variety of Earth lifeforms and fly on.

Re:Well, DUH! (0)

Anonymous Coward | more than 7 years ago | (#17668966)

You said virgin on Slashdot.

hehehehee

Re:Well, DUH! (4, Insightful)

Ignorant Aardvark (632408) | more than 7 years ago | (#17669032)

To be pedantic ... the absolute minimum time to explore the whole galaxy from Earth is about 80,000 light-years, because the farthest part of the galaxy is about 80,000 light-years away from us. Although to be even more pedantic, double that, because you can't really say you've explored until the information about what you've found has made it back to you.

So, yeah, you can't explore the galaxy in only a few thousand years.

Re:Well, DUH! (1)

QuantumG (50515) | more than 7 years ago | (#17669142)

Meh, it's still a phenomenally short amount of time.. on a galactic scale.

Self replicating probes?!? (2, Funny)

SeePage87 (923251) | more than 7 years ago | (#17669064)

Terrible idea. The Sylandro had one of them, and look what almost happened! Never trust a Melnorme.

Re:Self replicating probes?!? (1)

pluther (647209) | more than 7 years ago | (#17669270)

Hey now, you can't blame that one on the Melnorme. The Sylandro would have been fine if they'd thought it through a bit before attempting to reprogram the probes.

Re:Well, DUH! (2, Insightful)

myowntrueself (607117) | more than 7 years ago | (#17669180)

That's why you have to make the probes self replicating

Hopefuly they don't need to see any Earth-based SciFi to know that self replicating probes are a phenomenally *bad* idea.

Re:Well, DUH! (1)

susano_otter (123650) | more than 7 years ago | (#17669318)

Technically, humans are "self-replicating probes".

What if the probes are the alien civilization? Still a bad idea? Or just another Darwinian race for resources (which hopefully we can attend as observers, on account of our "probe" technology not needing the same resources as the alien technology)?

Re:Well, DUH! (1)

forkazoo (138186) | more than 7 years ago | (#17669308)

To paraphrase: But Sir! If we only send 8 probes it'll take billions of years to search a mere 4% of the Milky Way galaxy!

That's why you have to make the probes self replicating.. utilizing in-situ resources to make more probes at each star they visit, the growth becomes exponential and it only takes a few thousand years to search the entire galaxy. And seeing as we're visiting all these stars anyway, how about looking for planets that don't have life on them, but have nice suitable conditions for starting life on them. Cover a virgin planet with a wide variety of Earth lifeforms and fly on.


Ummm... The galaxy is something like 100,000 ly across. So, if we pretend that we were in the middle, that's 50,000 ly of travel in every direction. Assuming we could get a probe close enough to c as makes no never mind, then that's 100,000 years minimum for the probe to get to the other side of the galaxy and transmit a "Hello World" back to us. (Does it count as 'explored' if we can only declare that the probe probably made it by now, but we won't know if it made it for another 50,000 years?) I don't really conisder 100,000 to be a "few thousand." And *we* couldn't do it that fast -- only some hypothetical alients in the dead center.

Now, that assumes that the probe could accelerate to top speed really fast, so the time spend accelerating doesn't count. If the probe is stopping to build more of itself every few star systems, then it is going to have to slow down, stop, and spend time building new probes. On a 50,000 year journey, 4-ish years spent getting up to speed is quite negligible. And, since close enough to c as makes no never mind is really quite remarkably fast, it will probably take at least that long to get going (or to get stopping). Assuming a pit stop every ten ly (despite the fact that stars may be less than 1 ly apart in the densest parts of the galaxy, and our nearest neighbor is only about 4 ly), with the stopping and going deceleration time, it'll take about 14 years to cover the 10 ly. So, the outer edge of our fleet of probes will take something like 140,000 years to cross half the galaxy. Given our actual position, we will actually have like 3/4 of the galaxy to cross to get to the far edge, which would push up the time for exploration up to the best part of 200,000 years.

Figuring out how to accelerate your probes to close enough to c for this to be close to right, while also carrying enough propellant to slow down in the next system and refuel to be able to do it again is left as an excercise to the reader. Oh, and you have to lug an antenna big enough to send a signal back. (Or maybe just to the nearest probe which will relay it... But, that means no straight line path for the signal back home, which means it takes longer...)

Anyhow, the replicating probes idea is pretty neat, and I'm all for it, but we certainly won't have the whole galaxy explored in a "few" thousand years for any forseeable technology. If we can develop FTL and whatnot, all bets are off. the whole problem may turn out to be an x ly trip to the nearest black hole, and a y ms hop to anywhere in the universe.

Who say's they haven't? (1)

ack154 (591432) | more than 7 years ago | (#17668808)

From TFA:
unless they can develop an exotic form of transport that gets them across the galaxy in two weeks it's still going to take millions of years to find us

Who says they don't already have that transport? How would we know if they did or they didn't? Not that I know one way or another if there's any other life out there... but if it's possible there is not life elsewhere, isn't it also possible that there is life and that life that might exist possibly created some "exotic form of transport" already?

Interesting, but... (1)

someone1234 (830754) | more than 7 years ago | (#17668810)

Why would a supercivilisation build only 8 probes? They could have technology to detect Earth sized planets in the habitable zone. And they could send out hundreds of thousands probes to such planets. The problem is, if they don't have warp speed, these probes would not reach the planets until either the destination is already destroyed, or the sending civilisation itself is destroyed.

Re:Interesting, but... (1)

Ignorant Aardvark (632408) | more than 7 years ago | (#17669236)

Why would a supercivilisation build only 8 probes?They could have technology to detect Earth sized planets in the habitable zone.And they could send out hundreds of thousands probes to such planets.The problem is, if they don't have warp speed, these probes would not reach the planets until either the destination is already destroyed, or the sending civilisation itself is destroyed.
Please re-examine your time scales. The galaxy is only 100,000 light-years across. Now it's likely that a civilization could wipe itself out in the amount of time it takes to get anywhere, but the destination is still going to exist. Remember, solar systems and planets exist on time scales on the order of billions of years. A few hundred thousand years is a blink in cosmological time.

And keep in mind, if they're detecting habitable planets, they're probably going to find many of those within a small radius (remember, an average spherical volume of the Milky Way that is just 100 lt-yr in diameter contains millions of stars). It's not going to take hundreds of thousands of years to explore the nearer systems, it'll take hundreds or thousands of years. That's not necessarily even too long to miss the civilizations while they still exist!

Wrong (2, Funny)

TheWoozle (984500) | more than 7 years ago | (#17668836)

I need to introduce this guy to my next-door neighbor...

How close minded can one be? (2, Insightful)

quincunx55555 (969721) | more than 7 years ago | (#17668852)

...his conclusion is that aliens can't have had time required to find us yet."

Under what time frame? If an alien race has had advanced technology for 100,000,000 Trillion years, then they'd have plenty of time (and would probably have technology more advanced then sending out physical "probes"). It doesn't see likely from what we know, but I don't think we actually know that much.

Why is it that scientists think that only what we can achieve is possible? It's like us looking for aliens using our technology (SETI). Not that it's impossible, but I'd think other intelligent being could come up with other forms of communication than our own; even if it wasn't more "advanced".

Re:How close minded can one be? (5, Funny)

Rurouni_Jaden (846065) | more than 7 years ago | (#17668964)

"If an alien race has had advanced technology for 100,000,000 Trillion years, then they'd have plenty of time (and would probably have technology more advanced then sending out physical "probes")."

when they show up, please ask them how they survived the big bang.

Re:How close minded can one be? (2, Informative)

Kelson (129150) | more than 7 years ago | (#17668996)

If an alien race has had advanced technology for 100,000,000 Trillion years

That would be a neat trick, considering that as far as we can tell the universe is only on the order of 10 billion years old. Though 100 Quintillion years with high technology is probably long enough to figure out time travel, so I suppose this could still work.

Mankind's mastery of time (0)

Anonymous Coward | more than 7 years ago | (#17668864)

The Universe is much older then 10 Billion Years Old. Petty humans.

I once worked out (5, Funny)

Anonymous Coward | more than 7 years ago | (#17668878)

Traveling at the speed of light, it would take a quarter million years to reach Andromeda. What's more is that if I went into statis now, the compound interest on my savings would pay for the journey.

When they do find us . . . (1)

Slithe (894946) | more than 7 years ago | (#17668888)

We can always give their computer systems a virus.

Only 10% the speed of light? (1)

Apocalypse111 (597674) | more than 7 years ago | (#17668892)

They models used to reach the conclusion mentioned in the summary were calculated using a maximum speed of 10% the speed of light. Suppose that FTL travel had been developed by these advanced extraterrestrials - what then? I know it seems now like science fiction or fantasy, but you know the old adage about sufficiently advanced technology...

Self-Replicating Probes? (2, Insightful)

transiency (1053062) | more than 7 years ago | (#17668902)

What about probes that land and replicate on foreign terrestrial bodies? 1 probe lands and makes 10 or a hundred of itself. Send out 10 of these type of probes, and exponential growth will do your work for you.

What a fantastically stupid assumption (0)

gd23ka (324741) | more than 7 years ago | (#17668910)

Who says extraterrestials limited to sublight speeds? They may well have the ability to teleport
instantenously across the Galaxy. On top of that... who says they're from space light-years away?
They could be maybe have evolved on this planet or in this solar system millions of years before we
arrived on the scene. And then who says there is not an inhabitable why even earth-like planet
orbiting a Star within 20 light years from here?

Just because we don't know how to do it, doesn't mean someone else in the universe didn't find out
how to do.

The way I see it these scientists are humming a self-defeating mantra here.

More than one... (3, Insightful)

neurocutie (677249) | more than 7 years ago | (#17668930)

Whatever his assumptions are that leads him to 4%... it seems that he is considering only the probability that any ONE alien civilization is looking. But in all likelihood there are many, if not millions of alien civilizations out there than may be search, so the probability that any ONE of those million will find us seems quite a bit higher than 4%.

I'd be careful with all those probes (1)

zappepcs (820751) | more than 7 years ago | (#17668932)

in case one comes back wanting to be one with the creator - vger I anybody?

Some potentially invalid assumptions? (2, Interesting)

Red Flayer (890720) | more than 7 years ago | (#17668974)

1. Probes sent by extraterrestials cannot travel faster than our probes.
2. The ET search is not targeted.
3. The ETs are not much closer to Earth and found us by luck, early in their search.

At any rate, while the math is interesting, it just shows that we're not likely, as in snowball's-chance-in-hell likely, to have been found already. From a logical point of view, though, one cannot say that we haven't been found yet.

As far as we know for certain, the Vogon construction fleet could be circling our system as we type these responses... though the chance of that being the truth is small enough that we could very well see an Improbability-driven ship come in for a landing at JFK or LAX.

Re:Some potentially invalid assumptions? (2, Insightful)

LWATCDR (28044) | more than 7 years ago | (#17669198)

"1. Probes sent by extraterrestrials cannot travel faster than our probes."
Actually he is claiming that extraterrestrial probes can travel 1000 times faster than our probes.
So far propulsion systems are not following Moore's law and there is no evidence that they ever will.
This is a simulation made using guesses I would say that it is very interesting.

Calvin says (1)

TheCybernator (996224) | more than 7 years ago | (#17669000)

Sometimes I think the surest sign that intelligent life exists elsewhere in the universe is that none of it has tried to contact us.

Yes, and? (1)

CaffeineAddict2001 (518485) | more than 7 years ago | (#17669004)

Did he do any research showing that it's impossible for 8 people to find a needle in a haystack by evaluating one needle at a time?

Maybe he could then go on to propose that these people "self-replicate" and create more people to look for the needle? That would make it go faster. However this obviously would cause problems because inevitably they would end up competing for resources or start forming unions to demand that they only need to look at 3 needles at a time.

Aliens (0)

Anonymous Coward | more than 7 years ago | (#17669028)

Who's to say that humans aren't the most advanced civilization out there?

how many colonies of aliens? (1)

trb (8509) | more than 7 years ago | (#17669034)

Am I mistaken, or are this guy's statistics based on there being one other colony of "aliens" in the galaxy? What if there are a hundred colonies or a million? (A recent popular guess for number of starts in the milky way is 100 billion).

this reminds me of Thomas Aquinas (1)

A beautiful mind (821714) | more than 7 years ago | (#17669044)

"I think there will be never a quantum theory to prove that the universe is non-deterministic, a perfect case against my God proofs, so hereby I announce that my belief in God is staunch."

What's common in both viewpoints? Obviously one is real and the other is fictional, but what they have in common is that they both make predictions that we can't possibly do something in the future, so basically assuming no new technologies or scientific understanding.

not only that, but the SETI program hasn't either. (0)

Anonymous Coward | more than 7 years ago | (#17669078)

To date, the SETI program (perhaps more familiar to you from the SETI@home distributed searching aspect) hasn't had a single false positive, in the sense of the source turning out on further examination to actually be earth-based. Think about that. In 40 years [wikipedia.org] of searching for extraterrestrial intelligence, they haven't had to rule out a single terrestrial source.

One can't help but wonder: what exactly could there be for the extraterrestrials to find?

Physics (1)

pbrammer (526214) | more than 7 years ago | (#17669108)

The problem is that these assumptions are based on our (perhaps) flawed-physics knowledge. Our time is not their time. Speed of light could be slow to them. To think that space never ends and what could be out there is mind boggling.

ughh (2)

resignator (670173) | more than 7 years ago | (#17669122)

Speculations like this are complete garbage. Even assuming aliens would have to build a craft to travel here is too much. Who is to say aliens search, travel, or think anything remotely like us? It is like Christopher Columbus saying no one would EVER travel to the moon because sailing there would take more than one person's lifetime.

Why.. (0)

Anonymous Coward | more than 7 years ago | (#17669158)

Since the age of the Universe is of the same order, his conclusion is that aliens can't have had time required to find us yet."

The real question is, why would they discover us?

If their civilization is like ours, space exploration will take time, resources, and money. With the amount of those resources involved, you'd have to have a really good reason to colonize other solar systems. Sure, aliens might have been around longer than us, and could even be smart than us (maybe), but what makes us think they would want to visit us? We might be so far out of the way and boring that it's not worth it.

a few points to ponder though (2, Insightful)

bl8n8r (649187) | more than 7 years ago | (#17669226)

We are terribly limited by our own ignorance. We barely have an understanding of space travel, dark matter, string theory, time-and-space and many other things. I recall reading something once that said people in the early 20th century believed the human body would shake apart if we traveling faster than 25mph. The knowledge and intelligence of an alien civilization could be so far beyond our comprehension and knowledge that it's almost futile to even speculate. Right now, we think nothing can travel faster than the speed of light, however it wasn't too long ago people also believed the world was flat. I guess we can only make assumptions based on our current knowledge levels, but we must also take into account that there may be ways of doing things that we've simply not discovered yet, or cannot comprehend.

Nooo... so Roswell in '47 (0)

Anonymous Coward | more than 7 years ago | (#17669246)

...really was a hoax ? It can't be... We have belived...

AAAARRRGGGHHHH!!!

Meat? (0)

Anonymous Coward | more than 7 years ago | (#17669258)

They're made out of meat?

Shortsighted research (1)

Sefert (723060) | more than 7 years ago | (#17669260)

The idea of even firing someone into space was foreign to us only a century ago. Frankly, I would be stunned if, within the next several thousand years, humanity didn't figure out a way to fold space. There are tons of physicists that work on that type of math already (and higher dimensional math to boot). The geeks at IBM, amongst several other labs worldwide, have already figured out quantum teleportation. http://www.research.ibm.com/quantuminfo/teleportat ion/ [ibm.com] Frankly, why would anyone ever even assume that someone would travel in a linear fashion, trundling along from star to star? Of course it's a waste of time and would take billions of years - and to assume that all foreign lifeforms would be restricted to a form of travel that we personally, within only half a century of space flight, could conceive of, is arrogant and shortsighted.

Conclusion (1)

Srsen (413456) | more than 7 years ago | (#17669306)

his conclusion is that aliens can't have had time required to find us yet

Unless they have smarter astrophysicists.
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