Has anyone else used Drake Equation calculators?

[Tangle]

In that case, what were your results? I tend to be really optimistic and got 16-0.4 billion civilizations using different calculators. With the rare earth version, I got 6 billion.

The bbc's calculator: Here

[jwenting]

as the equation is a philosophical tool, rather than a mathematical one, and the values of the parameters aren't known and can't be known, there's no point in trying to solve it.

[magnemoe]

Also the calculator has some issues, number of stars born today is less important than the number born 3-8 billion years ago.

Number of planets with possibility of life is far lower than number of planets, not more than 10-20% of start with planets.

Chance of life is probably pretty high, chance of developing intelligence is unknown.

[SuperFastJellyfish]

Edit: Misread the OP's question.

[Nikolai]

Also the calculator has some issues, number of stars born today is less important than the number born 3-8 billion years ago.

Number of planets with possibility of life is far lower than number of planets, not more than 10-20% of start with planets.

Chance of life is probably pretty high, chance of developing intelligence is unknown.

Indeed. And the equation completely ignores the possibility of colonization of more worlds than one.

As a conversation-starter, the Drake Equation is as good as any for outlining some things we need to discuss as we attempt to discern the probability of intelligent life beyond Earth. But, as jwenting points out, it's not exactly rigorous, so "solving" it has limited utility.

[phoenix_ca]

Whether or not there is other intelligent life in the universe is, I think, a given. Even the most pessimistic (while still reasonable) estimates would result in plenty of other civilizations, given the sheer vastness of the universe.

Whether or not those intelligent life forms have any hope of ever meeting each other is another matter entirely. We won't have any inkling of whether or not that's possible until we completely disprove the possibility of FTL travel, or prove its possible.

It's also a more interesting question I think to contemplate the relative levels of development for those supposed civilizations. Just look at how much technological progress we've made in a mere hundred years. That's a puny, puny amount of time compared to the vast scale of the universe. If there is other intelligent life out there, compared to us, they may well be very, very different. Far, far from the portrayal in fiction like Star Trek. Probably closer to something like Babylon 5's Vorlons everywhere.

If there is life out there, I hope both them and us have sorted-out ethics regarding other life before we ever meet.

[Tangle]

as the equation is a philosophical tool, rather than a mathematical one, and the values of the parameters aren't known and can't be known, there's no point in trying to solve it.

Unless you're writing Sci-Fi.

[Tex]

I am of the opinion that there is a 100% chance of an alien civilization somewhere in the universe. Not sure about figures for our galaxy, but I find the equation unnecessary. I'm confident!

[Red Iron Crown]

Whether or not there is other intelligent life in the universe is, I think, a given. Even the most pessimistic (while still reasonable) estimates would result in plenty of other civilizations, given the sheer vastness of the universe.

I think it is certainly possible, even probable, that there is other intelligent life out there, but it is far from a given. We just don't have anywhere near enough data to draw a conclusion.

[phoenix_ca]

By a given I mean it's so likely as to be somewhat unreasonable to hold the opposite view (that there is no other intelligent life in the universe). There may not be solid proof but, as I said, even most pessimistic estimates end up with at least some intelligence somewhere.

I should've also mentioned there's no guarantee that we'd have any ability to communicate or even relate at all to some other form of life. Solaris covered that one pretty well (if in a rather drab and boring way, especially with the original movie; what the hell was with that car scene?).

[Albert VDS]

If the universe is infinite then there is no reason to think that we are alone.

Even if the universe is finite, it's still unimaginably large and thus a very tiny chance is still a huge number.

To me the question shouldn't be "are there other intelligent beings out there", but it should be "how far are they away from us".

[Red Iron Crown]

By a given I mean it's so likely as to be somewhat unreasonable to hold the opposite view (that there is no other intelligent life in the universe). There may not be solid proof but, as I said, even most pessimistic estimates end up with at least some intelligence somewhere.

Again, we don't have enough data to estimate how likely it is. We have one data point. Everything else is guesswork.

[magnemoe]

Again, we don't have enough data to estimate how likely it is. We have one data point. Everything else is guesswork.

We have some data, we know a bit about planet formations and can do estimates on how many has planets capable of advanced life. looks like its an decent chance a star have them.

Life started early on earth, pretty much as soon as it could, advanced life took longer but might had to wait for enough oxygen.

Intelligent life used plenty of time 400 million years from advanced life on land, might be an bottleneck.

civilization is another issue, might be impossible for many aliens, for us it took 10.000 years from farming to space, it could have taken 100.000 year with no problems, main issue is screw it up during the later phases.

Civilization life length is also totally unknown, best case millions of year if they use their solar system, billions if they go interstellar.

Now listen to radio waves is a long shot, earth is already reducing it broadcasts, switching to smaller and lower powered cells for higher bandwidth.

Anyway here is how I imagine first contact:

http://fc07.deviantart.net/fs70/f/2012/177/5/4/first_contact_5_by_olsen1a-d54w8yu.jpg

[Nuke]

i think there are zero civilizations in the universe. lots of barbarians though.

[Seret]

As a conversation-starter, the Drake Equation is as good as any

IIRC Frank Drake originally conceived it as a nice way of expressing the agenda for a convention. The fact it's endured shows what an inspirational thinker he was.

What is interesting about the equation is the way we're now starting to fill in the blanks a bit. The last few years have been a bonanza of discovery about the abundance of exoplanets, and we're starting to get a rough idea about the distribution of environmental conditions like gravity and insolation. Still way more guesses than data though.

[Nibb31]

Whether or not there is other intelligent life in the universe is, I think, a given. Even the most pessimistic (while still reasonable) estimates would result in plenty of other civilizations, given the sheer vastness of the universe.

Whether or not those intelligent life forms have any hope of ever meeting each other is another matter entirely. We won't have any inkling of whether or not that's possible until we completely disprove the possibility of FTL travel, or prove its possible.

This.

However, even if FTL is a condition for us, it might not be for some other lifeform. Even with FTL, a civilization where individuals have a lifespan of 2 years has no chance of ever reaching another star without generation ships. And a civilization of 100-meter tall giants with a lifespan of 5000 years could colonize other solar systems without FTL.

[Red Iron Crown]

We have some data, we know a bit about planet formations and can do estimates on how many has planets capable of advanced life. looks like its an decent chance a star have them.

Life started early on earth, pretty much as soon as it could, advanced life took longer but might had to wait for enough oxygen.

Intelligent life used plenty of time 400 million years from advanced life on land, might be an bottleneck.

civilization is another issue, might be impossible for many aliens, for us it took 10.000 years from farming to space, it could have taken 100.000 year with no problems, main issue is screw it up during the later phases.

Civilization life length is also totally unknown, best case millions of year if they use their solar system, billions if they go interstellar.

Now listen to radio waves is a long shot, earth is already reducing it broadcasts, switching to smaller and lower powered cells for higher bandwidth.

Anyway here is how I imagine first contact:

http://fc07.deviantart.net/fs70/f/2012/177/5/4/first_contact_5_by_olsen1a-d54w8yu.jpg

We are getting more data than ever about planet formation, but we still have almost nothing about the likelihood of life (and later intelligence and civilization) developing. If either of those factors is extremely rare, I don't think it's a given that there's any other intelligent life.

I'm really playing Devil's advocate here, I suspect that there is other intelligent life out there, I just don't think we can consider it likely enough to call it a given.

Also, this sort of discussion makes me think of this:

[whynot]

i think there are zero civilizations in the universe. lots of barbarians though.

This. Whynot make zip/nil/zero an option in the poll?

[Tangle]

This. Whynot make zip/nil/zero an option in the poll?

Because honestly that's just deciding that going to the moon still isn't worthy of being declared a race with the capability of space travel.

[LABHOUSE]

There have been many human civilizations on earth and God may have made more earths.

[KerikBalm]

The question is to vague... in the universe? in the multiverse? in the observable universe (given that the expansion of the universe will create event horizons between us and distant points), the galaxy?

What qualifies as a civilization? Would something like an ant colony count? are we only counting those that can send signals (of any sort, although there isn't much plausible aside from EM radiation) into space? only those that can navigate space?

FWIW, I do not believe there are any civilizations that are capable of interstellar travel within our galaxy. Therefore I believe we would be the first if we were to acheive fusion power.

FWIW, I got 0.5 billion planets with intelligent life using that calculator, and I think I was being generous.

Edited May 23, 2014 by KerikBalm

[LABHOUSE]

Well intelligence is hard to define the alien civilization's average IQ may be 150 on our scale but only because on guy there had a 500000 IQ all the rest have 80 or lower.

And also pulsars send out radio waves so that's out lasers for communication can also just be a white dwarf so you can never tell also a sea faring civilization may be super smart but lack thumbs or even figures and toes for that matter so telepathy is their only hope of building stuff.

[Omicron314]

About 3 solar masses worth of star is created each year, but most of those are red dwarves, so I put the number of stars created each year at 6 (although that's probably a bit high). It seems likely that most, if not all, star systems develop planets, so I put that value at 100%. However, Kepler data suggests that one in five sun-like stars has a terrestrial planet in the habitable zone, so I think the number of habitable planets per star system is about 0.2.

Then it gets a little harder.

Due to the fact that Earth life arose very shortly after the continuous orbital bombardment of the surface ceased, it seems that most habitable planets develop life. However, "terrestrial and in the habitable zone" is not equivalent to "habitable". The thickness of the atmosphere and the strength of the magnetic field can vary greatly from planet to planet (just look at Venus and Mars). Both Venus and Mars are in the habitable zone, so I'll use 33% for this value as I have nothing better to put.

For the intelligence factor, I am going to side with the "life trends towards intelligence" side. Yes, many many species have existed on Earth over the course of it's 4.5 billion year lifetime, but the ancestors of modern humans were in a much better position to develop intelligence than any other species before. Life began simple and worked its way up towards intelligence, so that now we have a whole host of intelligent creatures from humans to apes to octopodes to crows, and most stars in the galaxy are red dwarves, which have lifespans of trillions of years. It seems likely that most planets with life eventually develop intelligence. Thus, I set this value to 85%.

If we turn the "percent civilizations that can communicate across space" bit into "percent civilizations that destroy themselves" (I put 50% (although it should probably be less): we came very close to nuclear war with the Soviet Union several times over the course of the Cold War) and take the length part to mean how long a surviving civilization lasts (if they overcome the threat of destroying themselves, probably a very long time), we get a more interesting answer. It tells us that there are about one and a half million civilizations in the galaxy. Most of them probably wouldn't be detectable, though. If we assume that all civilizations get the ability to send radio waves out into the galaxy but this period only lasts about 100 years (as seems to be the case with our civilization), that means there are only about 34 detectable civilizations in our galaxy. That few civilizations means that we probably will never detect another alien civilization, unless the more advanced ones purposefully contact us or we ourselves gain the ability to detect their "radio" chatter.

Still, 1.5 million civilizations means that around only one in every 200 (0.5%) stars has ever hosted a civilization, and only in every 9 million or so (0.00001%) have a civilization around our own level of sophistication that we could detect. With these statistics, SETI seems like a pointless endeavor. To scan 9 million stars in 100 years would mean that each star would only be given 350 seconds of listening time, which is simply unrealistic. Of course, building more arrays would enable us to scan that same number of stars in significantly less time, but the nearest civilization would still be so far away that the chances of detecting them would be minimal.

But still, one in 200 is a lot. There could very well be an advanced civilization within one hundred lightyears of us, more than capable of determining the existence of life on Earth through spectral analysis. We may have no idea where they are, but don't be too sure about them.

[Nuke]

Because honestly that's just deciding that going to the moon still isn't worthy of being declared a race with the capability of space travel.

i was more pointing out that i dont consider humans civilized at all, and i doubt that other life forms in the universe would be any different. hence 'lots of barbarians'. frankly, humans still act like monkeys, monkeys that have gone to the moon, but still monkeys. we are not as civilized as we think we are. our social structures still closely resemble the natural pecking order of your typical monkey troupe. the only difference is a matter of scale, and possibly our tools being slightly more advanced.

it also makes things interesting in a first contact scenario.

[rkman]

I'm really playing Devil's advocate here, I suspect that there is other intelligent life out there, I just don't think we can consider it likely enough to call it a given.

What is the basis for that, in light of the cosmological principle? If that principle is accepted, does your scepticism not require a reason to think that our spot in the universe is very special - whereas everthing we know points to that not being the case?