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Number of ET Civilizations In Our Galaxy Is 37,964
KentuckyFC writes "The famous Drake equation calculates the number of advanced civilizations in our galaxy right now. But the result is hugely sensitive to the assumptions you make about factors such as the number of habitable planets that orbit a host star, how many of these actually develop life and what fraction of these go on to become intelligent etc. Disagreements about these figures leads to estimates for the number of advanced civilizations ranging from 10^-5 to 10^6. Now an astronomer in Scotland has worked out how to make the calculations more precise so that different theories about the origin of planets, life and civilizations can be compared. His calculations say that the rare-life hypothesis predicts only 361 advanced civilizations in the Milky Way now. However, the so-called tortoise and hare hypothesis predicts 31,573 and the theory of panspermia says that there ought to be 37,964 extraterrestrial civilizations more advanced than our own in the Milky Way."
Make that 37,965. My colleague surely has one growing in his tea cup.
yuck.
...of spurious precision.
Should give us plenty of room to screw up without affecting anyone.
The simple truth is that interstellar distances will not fit into the human imagination
- Douglas Adams
I'd be interested to know where the best place to look for ET civilizations is. A common science fiction theme, found in plausible for in Niven's Known Space universe and Vinge's rather implausible A Fire Upon the Deep has civilizations getting out of the core as fast as possible, settling the fringes of the galaxy. The increased speed of stellar activity in the core would make for a risky place to build lasting civilizations. Would everyone better than us be at the outskirts?
1.
And it is as valid as this astronomer's estimation.
See my journal for slashdot ID's by year. Mine created in 2005. http://slashdot.org/journal/289875/slashdot-ids-by-year
The "famous Drake equation" is NOT meant to calculate anything, it's meant to start a conversation on what the parameters of intelligent life probability are.
On the other hand, the famous Fermi Paradox tells us that we're alone in the galaxy. And considering that's a direct piece of data, I tend to believe this view. People like to wave their hands and say, but, but, WE'RE here! That means that there "just have" to be more! Why are we so unique? This is the Sagan argument, and it's answered by the Anthropic Principle.
And yes, in this case, absence of evidence *IS* evidence of absence.
Sometimes it's best to just let stupid people be stupid.
No mention of species less advanced than us, but there are apparently 37,964 more advanced. I wonder why that is... Other civilizations must look at this backwater hick-world and laugh.
Admit it. You post strawman arguments as AC so you get modded Insightful for refuting them, rather than Troll
We just don't have a clue.
The number of things we don't have a clue about is staggering.
Counting the number of earth like planets is just plain silly. If life can only start in space and then find a planet, earth might be totally unsuitable for the first start. It also presumes life can only exist under earth like conditions yet we KNOW that even life on earth varies widely. If some species can survive on the bottom of the ocean outside the influence of the sun, is it impossible to imagine a lifeform that exist in space itself?
No, I am sorry but until we can actually go and look our estimates of the number of civilizations is between 1 and 1+.
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
But we have no definition of advanced.
Look, just because an alien civilization has been around longer than we have, doesn't necessarily mean they will be more advanced than we are.
Maybe they could have been around one million years before us, but are stuck somewhere between Mesopotamia and Rome.
I'm god, but it's a bit of a drag really...
I follow the Mass Effect way of thinking. A handful of civilizations, each with dramatically polarized stereotypical traits, and who speak English with perfect North American accents, regardless of the structure of their mouth(s) and/or vocal cords (assuming they have them...).
Admit it. You post strawman arguments as AC so you get modded Insightful for refuting them, rather than Troll
Because a species of intelligent dolphins would surely be detectable from their radio transmissions.
No. That entire line of thought is based upon the incorrect assumption that WE are the model for all other species.
We're almost unique on Earth. Where we share DNA with every other animal. Why expect that from creatures who evolved on a different world?
Not to mention the incredibly SHORT time we've been looking over an incredibly SMALL portion of the galaxy.
Your entire argument is based upon another species developing the exact same technology that we have ... and using it in a fashion we can detect ... far enough in the past ... but not too far in the past ... so that we can detect it ... using the technology we have ... during the time we have been trying to detect it.
Yeah, like that "proves" anything.
I am a polar bear. Don't bother to ask me how I managed to get on Slashdot and post this, you would never believe it.
However, I have been doing some estimations of my own. I have always wanted to figure out how many polar bears there are in the world. In my neighborhood here in the arctic, there aren't too many polar bears. About 350. I estimate that we roam over 20 square kilometers. Now, based on some observations I made from the bottom of a well, I figure the earth is around 500 million square kilometers. I haven't actually been outside of my corner of this world, but I imagine everything must be like it is here, and life must be exactly like it is here. I have no evidence to the contrary.
So, I figure there must be 25 million times 350 polar bears or 8.75 Billion of them.
See my journal for slashdot ID's by year. Mine created in 2005. http://slashdot.org/journal/289875/slashdot-ids-by-year
But, the diameter of the milky way is about 100,000 light years - so, if we assume that pre-Galileo civilization was oblivious to ET, we as a species are only aware of civilization signs within 400 light years or so.
So, if there are 40,000 civilizations within a 100,000ly diameter, then there are approximately 2.56 civilizations within a 800ly diameter.
Personally, I feel like Earth represents the .56 of a civilization in that scenario...
That reminds me of this article from the Onion.
today :
http://edition.cnn.com/2008/WORLD/europe/10/20/britain.ufo.sightings/index.html
Read radical news here
How many of that have stargates?
Michael Crichton criticised the Drake equation years ago:
http://www.crichton-official.com/speech-alienscauseglobalwarming.html
My personal guess is that there are OVER 9000 civilisations out there.
Squirrel!
No kidding. Our current estimates of the number of stars in the galaxy only go to about one significant figure, with upper and lower estimates differing by a factor of two. That puts a pretty serious cap on the precision of his answer.
One of my peers is an astrophysicist. Nearly all of their calculations are done to ONE significant figure. It ends up that they typically just add up exponents. The numbers are usually so huge, eg. 1E27, that they can get away with this.
:)
When you are dealing with orders of magnitude like these, it is usually acceptable in the scientific community. Whether this de-facto standard *should* be so acceptable is still up in the air in my views
Civilizations that manage to survive reach technological singularity, and simply hole up.
Ephemeral civilizations have only a short time to detect each other; I doubt that happens often.
It's now 37,962. The Qnak'k'z of Kuberon II just set off a prototype nanoplasmic bomb that wiped out the whole planet. The timid and peaceful Fnumri of Kuberon VI's third moon were not directly affected, but the flash gave them such a fright they all died of double heart attacks. Sad indeed.
At the bottom of the
You're missing an entire aspect to the Fermi paradox.
The universe is old. VERY old. About 14 billion years. Earth is fairly young, about 4.5 billion years.
Assuming intelligent alien life take about as long as intelligent Earth life to evolve (give or take a billion years), these other civilizations would have billions and billions of years ahead of us.
Or 4352342. "Calculating" any such number is not in hardly more scientific than throwing dice to figure it out. Sometimes I wish scientists wouldn't have this urge to make the impression of having a clue, when, quite obviously, the don't have a clue. Or, as in this case, provably cannot have a clue.
Now one knows yet how life came into being. Stop making calculations that require knowing that to even get close to meaningful numbers.
With NTSC analog TV going away next year, one of our big identifiable sources dies
True, but any alien civilization that has been viewing our broadcasts has been given fair warning of the switch and have been told where they can obtain a digital receiver box with a government coupon.
The Internet is generally stupid
Correct me if I'm wrong here, but an Earth-like planet couldn't have come about much sooner, since we need so many elements that we can only get from old burned-out stars. There's gotta be a lot of cycles before there's enough material further up the atomic chart to make an interesting planet.