Maybe There's No Life in Space Because We're Too Early

Long-time Slashdot reader sehlat shares "a highly accessible summary" of a new theory about why we haven't yet find life on other planets -- that "we're not latecomers, but very, very early." From Lab News: The universe is 13.8 billion years old, with Earth forming less than five billion years ago. One school of thought among scientists is that there is life billions of years older than us in space. But this recent study in the Journal of Cosmology and Astroparticle Physics argues otherwise... "We find that the chance of life grows much higher in the distant future..."

Stars larger than approximately three times the Sun's mass will perish before life has a chance to evolve... The smallest stars weigh less than a tenth as much as the sun and will glow for 10 trillion years, meaning life has lot of time to begin on those planets orbiting them in the 'habitable zone'. The probability of life increases over time so the chance of life is many times higher in the distant future than now.
The paper ultimately concludes that life "is most likely to exist near 0.1 solar-mass stars ten trillion years from now."

Comments

Obligatory Star Trek: TNG episode

[Yvan256]

So, we're those guys after all?

Re:Obligatory Star Trek: TNG episode

[somenickname]

I think the first few seasons of Babylon 5 is a better analogy. In fact, the first few seasons of Babylon 5 is basically about the struggle between the older races and the younger races. It's possible that we are one of the "old ones" but an early stage. It's also possible that we are one of the younger races but, to the "old ones" we are nearly indistinguishable from ants (G'Kar gives a nice speech about this).

On a more serious note, anyone who has sat and given some thought to what the TFS talks about has probably realized that we could be one of the earliest sentient races. The universe didn't start with the ingredients of life. It was brewed in stars and then spread by the exploding of stars and the re-coalescence of that material. That shortens the possible time frame for sentient life but, you also need a fairly quiescent part of the galaxy to give sentient life enough time to form. So, really, it's impractical for sentient life to arise until *all* nearby giant stars have gone supernova. Then you have the time it takes for new solar systems to form and stabilize, basic life to come into existence, mass extinctions, the possibility that lifeforms unsuitable for sentience will dominate a planet, etc, etc.

It really takes an extraordinary amount of luck, over an extraordinary amount of time, for sentient life to form. And, as we've seen in the last century, it also takes a lot of luck for a technological society to not destroy itself.

Re:Obligatory Star Trek: TNG episode

[dryeo]

It really takes an extraordinary amount of luck, over an extraordinary amount of time, for sentient life to form.

I prefer the term technological life as it our use of technology (along with our story telling) that really sets us apart. Currently on the Earth we have a few examples of life that may be sentient.
Octopus, where their environment really puts them at a disadvantage, but the killer is no family/tribe so no passing on knowledge. Every Octopus is born alone and starts over from scratch. Humanity has been building on our ancestors knowledge since before we were human and the fact that we're story tellers sets us apart.
Dolphins may be sentient, but no appendages for tool use as well as that wet environment. Some birds such as Ravens and Parrots may also be sentient, but once again not built for tool use and probably not much knowledge passed on.
Who knows about previous life. The dinosaurs were around for ages and some may have been sentient but without the means of passing on knowledge. Same with lots of previous life, especially the ones that had the bad luck to be flattened by a meteorite, volcano or other natural disasters.
And as you say, just the luck needed to have a planet that stays inhabitable for the billions of years required for evolution.

One of many famous Fermi Paradox answers

[Frobnicator]

The Fermi Paradox was described over a half century ago.

The "somebody has to be first" option is one of many options for why we don't see a Universe swarming with life.

There are quite a few other options. Unfortunately with my faith in humanity, I'm guessing the intelligent species tend to destroy themselves options is more realistic.

Re:One of many famous Fermi Paradox answers

[HuskyDog]

I am afraid that I have never been persuaded by "civilisation will destroy itself" arguments, because (a) they have a poor definition of "destroy" and (b) options for further evolution don't seem to be well considered.

Expanding briefly if I may: Most cataclysmic events postulated don't seem cataclysmic enough. Suppose for example there was a huge nuclear war. Might that and the ensuing nuclear winter push humanity back to the dark ages? Well, very possibly it might, but we know from practical experience that getting from the dark ages to now takes about 1500 years or so, probably rather less if you have the smoking remains of the previous civilisation to get clues from. So, we get another go at being an advanced civilisation and presumably can repeat this depressing episode over and over again (see Azimov's excellent 1941 short story Nightfall).

For these cataclysmic events to actually make mankind extinct the population has to be reduced below a practical reproductive minimum (which clearly depends at least in part on how spread out the survivors are). We could imagine perhaps some sort of synthetic plague to which no-one is immune and which survives in the environment to such an extent that even small highly isolated populations are eventually infected. It sounds a bit unlikely to me, but again we know from experience that given a few million years our ape cousins will evolve to replace us. Of course, all primates could also be vulnerable to the disease, in which case we just have to wait even longer for an evolutionary replacement.

Conclusion: Short of managing to destroy all multicellular life forms, planets which evolve advanced life will have advanced civilisations from then on with possible gaps.

Re:One of many famous Fermi Paradox answers

[Anonymous Coward]

One problem with rebuilding a technological civilization is that it's built on the availability of energy resources. You start with wood then coal, oil, gas, then nuclear for example. They tend to build on each other and each one requires the energy production of the one before. If you need to rebuild from scratch you may have already used up the easily available resources from before. Then you would be in a position of having to develop solar, wind, nuclear using only wood/steam powered machines. That could prove to be a great challenge. It may be that there are technological civilizations that used up most of their resources, had a large war, pushed themselves back to the stone ages, and were no longer in a position to rebuild energy production technology.

Re:One of many famous Fermi Paradox answers

[BlueStrat]

Unfortunately with my faith in humanity, I'm guessing the intelligent species tend to destroy themselves options is more realistic.

My view is that intelligent species indeed do not destroy themselves, it's simply that humans have not yet been proven to be intelligent.

If humans are still around in a few millennia, then maybe humans can be considered "intelligent".

Strat

Re:And we see history

[ShanghaiBill]

Thousands of lightyears, sometimes even more, so we see thousands of years in the past

The Universe has been around for 13.8 billion years. A few thousand years one way or the other is insignificant. TFA isn't talking about us being a millennium ahead of other civilizations, it is about us being billions of years too early.

So similar to Star Trek, we just might get to know the club when we qualify for it (FTL Communication or Travel).....

Even on Star Trek, there are many civilizations that decline to join "the club". Star Trek is silly anyway, because it is unlikely that so many civilizations would reach nearly the exact same degree of development at exactly the same time. Also, as we learn more and more about physics, we get more and more confirmation that FTL communication/travel is fundamentally impossible. It is highly unlikely that interstellar travel will ever be like taking the train to work.

Depends on your definition of "life"

[MetricT]

Bacterial life appeared on this planet basically the instant asteroids stopped bombarding the planet. For all we know, life was created and destroyed several times before the Late Heavy Bombardment ceased. So it appears that simple bacterial/viral life may be commonplace throughout the cosmos. Indeed, there are tantalizing signs that Mars and Titan may harbor some form of life.

On the other hand, complex multicellular life only appeared in the last billion years, which suggests that the leap from single-cell -> multicellular life is somewhat difficult. Our sun won't be conducive to life in another billion years, so complex life "barely" made it here.

I would love to be wrong, but given the fact that planets appear to be commonplace throughout the cosmos, and we have yet to hear from anyone, it starts to shift the odds towards one or more of:

1) Complex life is relatively rare and widely separated in space and time.
2) Complex life doesn't survive long-term (nuclear war, grey goo)
3) Complex life does survive, but for some reason doesn't communicate or colonize other worlds (a "Prime Directive", or perhaps they "sublime" in the Ian Banks/Culture sense)

I actually lean a bit towards 3 myself, but humanity will eventually find out, one way or the other.

Re:Depends on your definition of "life"

[Dutch Gun]

3) Complex life does survive, but for some reason doesn't communicate or colonize other worlds (a "Prime Directive", or perhaps they "sublime" in the Ian Banks/Culture sense)

Or because no one has found a way around that pesky speed-of-light barrier, and the vast distances simply make inter-species communication, let alone travel, utterly impractical. This has always seemed, at least to me, the least romantic but most pragmatic answer to the question of why we don't meet aliens, or even hear from them.

Re:Depends on your definition of "life"

[Chelloveck]

Or because no one has found a way around that pesky speed-of-light barrier, and the vast distances simply make inter-species communication, let alone travel, utterly impractical. This has always seemed, at least to me, the least romantic but most pragmatic answer to the question of why we don't meet aliens, or even hear from them.

I can't buy that, either. Intelligent machines must be possible -- after all, we're just meat machines, and unless there's some divine entity handing out souls there's nothing particularly special about us naturally-evolved organisms that couldn't be duplicated in an artificial organism. So it should be possible to purpose-build intelligent machines and send them out as interstellar probes. Make it so the intelligence can hibernate for the journey by powering down.

Now, let's say the probe is only moving about the same speed as Voyager, 17 km/s. We know that's easily achievable. At that rate it'll take about 17,000 years to travel one light-year. So let's say our robot probe travels 100 light-years to a nearby star (1.7 million years travel time) and sets up shop. After another 300,000 years it's ready to launch two more probes. Each of them goes 100 ly and repeats. At this rate it only takes 2 billion years to span the galaxy, and we end up with something like 10^300 (2^1000) probes. Maybe we ought to build in a limiter that stops reproduction when a probe hits an already colonized system...

Mind you, that's with some really pessimistic numbers. And it doesn't even need machine intelligence, I just think a machine has a better chance of functioning after a couple million years of travel than a hibernating meat popsicle does.

Re:Uh, no

[argumentsockpuppet]

Space is big. Really big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist, but that's just peanuts to space. - Douglas Adams

But that's not the same as saying that intelligent life can't spread across a big space. There are some limits imposed by the speed of light and the speed of the expansion of the universe. That said, machines, intelligent machines with personalities of humans, couldn't spread ourselves around.

Imagine waking up after a journey of a couple million miles and being the one who guides new life to intelligence. Maybe you do a little job here or there to make sure life develops. Maybe you perform a "miracle" or two for primitive lifeforms to keep them headed in the right direction. Maybe eventually you create a biological life-form to direct them to things that will eventually build a society capable of surviving long enough to propagate themselves into space. Sure, you'll get blamed for a lot of stuff that you don't do to keep them happy, but if your goal is expansion of intelligent life in the universe, you take the good, you take the bad you take them both and there you have the facts of life. In the universe and whatnot. Maybe humans aren't even the first.

Re:And we see history

[Nemyst]

Even on Star Trek, there are many civilizations that decline to join "the club". Star Trek is silly anyway, because it is unlikely that so many civilizations would reach nearly the exact same degree of development at exactly the same time.

Is it though? Star Trek depicts a universe teeming with life, and in that context there will be numerous civilizations at pretty much every level of advancement possible. They show that in the series too: many episodes revolve around an incredibly advanced or primitive civilization, or even talks about distant past civilizations long since gone.

Also, as we learn more and more about physics, we get more and more confirmation that FTL communication/travel is fundamentally impossible. It is highly unlikely that interstellar travel will ever be like taking the train to work.

FTL travel is just the classic exception that allows sci-fi to work. Without it, just about everything in Trek would be impossible, but nowhere does Trek imply that this will happen. Instead, Trek is "assuming this is possible, what could happen?"

Guess based on no data.

[jellomizer]

The issue that I have with this hypothesis of the article. Is making a guess that places us many standard deviation out from the median just because there is no data. With the lack of data we should assume that we are average in every way at least within 1sd.

Re:And we see history

[ShanghaiBill]

The Universe has been around for 13.8 billion years.

We humans are so cute, thinking we know so much, with such certainty.

Actually, the age of the Universe is 13,820,000,003 years. We figured out that the age was 13.82B, but that was back in 2013, hence the additional 3 years.

Yes, shorter by ~30MYr according to the paper

[Roger W Moore]

On a more serious note, anyone who has sat and given some thought to what the TFS talks about has probably realized that we could be one of the earliest sentient races. The universe didn't start with the ingredients of life. It was brewed in stars and then spread by the exploding of stars and the re-coalescence of that material. That shortens the possible time frame for sentient life

Actually if you actually read the paper (yes I know it's Slashdot so you are excused! ;-) they mention this there. All the ingredients for life, including the heavy elements, are there in the second generation stars which formed a few million years after the first generation of stars which were around ~30MYr after the Big Bang. The large stars which go supernova have very short lifetimes so heavy elements were created and dispersed into the coalescing gas clouds really quite rapidly. So instead of ~13.6 billion years for life to evolve you have ~30+a few million years less i.e. negligibly less time.