Now that believing in aliens is somewhat mainstream thanks to Kepler, Gallileo, Cassini...

back to with your UFOs and reptilians retard. This is a science board not for your roleplaying autism.

Nonsense, we have lots of data... no, no, no, no... and no, microbes on Jupiter... maybe...

Enceladus has all the conditions for life. By your logic believing in the existence of exoplanets prior to the 1990s was /x/ because "muh no evidence"

ayylmaos are very rare but they most likely exist in some form
we will never meet any though because distance

Maybe you're the autistic one if you don't realize that the last five are jokes.

Level 2. Level 3 if I go into I want to believe mode

the joke went so far over your head, I think it's in orbit now

Level XI Aliens are between us & the Bogdanov twins are Aliens friendly toward humans, unlike the reptilians.

Level 2.

Level 0.5: believes that life will eventually develop somewhere else, but due to the universe's young age it simply hasn't had the time yet

we don't even know if there's a liquid ocean on enceladus yet, let alone everything else

>In 2014, NASA reported that Cassini found evidence for a large south polar subsurface ocean of liquid water with a thickness of around 10 km (6 mi)

>We have no data at all on the topic.
We have plenty of data: one positive observation and many negative observations (they count as well; every potential location for aliums to be, that was subsequently checked and refuted, should reduce your posterior belief in their existence).

Level 0.5: I believe there is [the strong possibility] of life somewhere out there in the universe

Maybe 0.75 - I'll give a strong possibility for life within the galaxy - maybe not intelligent or complex life, but life.

I'll even give a slim possibility for some primitive life within the solar system.

There's nucleotides on asteroids and shit, and life isn't made up of anything unusual, element wise... So some RNA churning in some mud somewhere - it could certainly happen elsewhere, so long as the odds are better than 1 in 10^24. Sadly, we don't know what those odds are though. The abiogenesis attempts we've made show some possibilities, but even if they came to full fruition, we can't be certain how often those conditions occur in the universe, so unless and until we find something... We just don't know.

On the other hand, we also now know that most stars have planets, and that this isn't the most likely sort of star to have rocky planets like ours, and the type that is most likely to, is about a hundred times more common, and lasts about a hundred times as long. And we keep find more and more extremophiles changing what we believed to be the conditions required for life - even if we can't always be sure if they could have came to be without more favorable conditions to evolve from.

Intelligent life is a whole other ball game, as there's a lot more factors involved, and, probably, a lot more routes to take - and then there's the question as whether we would *recognize* it as intelligent life.

Well currently available evidence points to there being no life outside of earth. However our sample size is low, which damages my confidence in that conclusion. But until I see some evidence in favor of extraterrestrial life, that's what I'm going to stick with.

Now what do [math] believe [/math]. Well I believe that universe is largely hostile to complex life (you only need to look at all the extinction events on earth to see that), so complex life is going to be incredibly rare. As for intelligent life, that's going to be much, much rarer. Couple that with the fact we're only like a fraction of the way through the period of history in which life can form, makes me believe that we're actually among the first intelligent life to form in the universe. For more information, see:
arxiv.org/abs/1606.08448
Which estimates that the probability of life forming peaks about 10 trillion years in the future.

Well, we maybe in that first 1%, but you do realize how many opportunities came up simultaneously, or slightly before us, throughout the universe.

And intelligent life, if it goes full bore spacefaring and colonizes even a few well spread planets, pretty much can't go extinct in any conceivable fashion... At least in no way that doesn't also result in the end of the universe. Should it, for whatever reason, choose to, it could colonize every planet in a galaxy, even at sub light speeds, in just a few million years. Even an interstellar war with relativistic planet-kill weapons is probably going to leave at least one survivor to repeat that process. So, once you've reached that threshold, you're kinda immortal, as a species.

It's true, a whole lotta things had to come together just right to give us complex life, intelligent life, and civilization here - but at the same time, any number of things may have happened to cause it to happen sooner (particularly on the civilization front - there was a lot of unnecessary setbacks and meandering there). Even if another species took instead, even longer, we didn't start so early that they couldn't have a billion year head start on us anyways.

Granted, assuming FTL isn't a thing, and it didn't happen in this galaxy, we'll probably never know, but there are nearly countless numbers of planets out there, probably nearly countless numbers of Earth-like planets, most of which have been around as long, or longer, than ours has, so I wouldn't be so quick to dismiss the possibility - given that there's probably roughly 10^24 such possibilities.

Level 0: don't really care

I'm just presenting the science as I know it. And it's not favorable. Sure it might change in the future, but that's how it stands.
>given that there's probably roughly 10^24 such possibilities
How have you arrived at this?

>I'm just presenting the science as I know it. And it's not favorable. Sure it might change in the future, but that's how it stands.
I'm saying the science says otherwise - I mean, yeah, the odds of life go way up in the future, of course, but aside from us being here, there's nothing at all unique about this solar system. There's boatloads of others nearly just like it.

>How have you arrived at this?
Estimated number of stars in the observable universe, times average number of planets, reduced by the ratio of the chance of them being in habitable zones, all based on the average observed around stars so far.

So yeah, rough as fuck. Any way you slice it though, lotta opportunities, but we really don't know enough about how life forms to know what the odds of life are. It seems unlikely to me, but the odds could actually be worse than that - in which case we might be the only life, ever - barring any we create in turn.

>There's boatloads of others nearly just like it.
Right, but I'm not arguing that there's something special about this solar system, just that in order for life c to thrive an improbable series of events have to happen. As for life forming in the first place, there's no good agreed upon hypothesis (AFAIK at least), so it's hard to estimate.

>all based on the average observed around stars so far.
Right, but if the probability of life forming is, as far as we can tell, about 1 in 10^24. Like I said it might change in the future, but that's how it looks right now. As says the number of null results we have should reduce our posterior belief.

Level 3. It's more of a i want to believe.

>the number of null results we have should reduce our posterior belief.
Eh... That's kinda looking like at sand on a beach from high orbit with the naked eye, and concluding the crab you have in the fish tank next to you is the only one that exists.

I admit we can't get a *good* number, but we also can't get a good look at any other potentially habitable planet outside the system, beyond to say they are there. For all we know they could all have life on them, and we likely wouldn't be able to tell. At best, we've looked at bits of Mars as a potentially *formerly* habitable one, and found nadda.

We know all the elements life is made up of are common, that the conditions to sustain it, if less so, seem to repeat all but endlessly, under the assumption that the rest of the universe is largely repeats of the systems we see around us, as all evidence suggests - and that the stars that tend to have rocky planets like ours, are more common our own star and longer lived to boot. We don't know exactly how life comes about, but we do know there are a great number of solar systems with planets under similar conditions to our own, so they can't really be considered null results. They are all potential candidates, even if that knowledge gap prevents you from figuring the exact potential.

>That's kinda looking like at sand on a beach from high orbit with the naked eye
Right, but it's evidence. I said right at the start that thec small sample should reduce reduce your confidence in the conclusion, and that it could change in the future, but that's what we conclude as of right now.

same. red dwarf planets have too much radiation. yellow stars with planets in the habitable zone = life. intelligent life is rare though. it took earth until just now to have intelligent life and even the galaxy itself has its habitable zone.
Level V: I believe there is bacteria on Mars

Well there's little to no confidence in any conclusion, but the fact that there's likely so many places experiencing similar environmental and chemical scenarios, does rather up the odds, even if a key factor is an unknown.

Though comes into play, as it isn't too hard to tweak that unknown to reduce the odds so much that there's unlikely to be any other instances in this galaxy - and if there isn't - we may never expand that sampling beyond one, regardless of how many there may be out there.

>red dwarf planets have too much radiation
Meh, water stops radiation like nothing else, and radiation in general is overrated. Tidally locked isn't much an issue either, given how often planets pick up billions year long spins, even without a sizable moon. On top of that, those red dwarves tend to have a lot more rocky planets, and a larger happy temperature zones, and provide more light to more of that zone to boot.

I kinda suspect, if there is intelligent life out there, and it's searching for other life, it may very well be passing us over, thinking that life can't exist around a yellow star. (Let alone the odds of finding it way out here in the sparse boonies of the far arms of the galaxy.)

...then again, as many have pointed out, that maybe a good thing.

yeah i guess there could be fish and stuff, i didn't really think about that. i can't imagine there ever being intelligent life on a waterworld tho

me

i just want to clarify that i think that there is life in mars groundwater, nothing on the surface.

Water isn't the only way to get out of radiation, but pretty much all the biogenic theories tend to think life tends to start in water. If there's underground grottos, one would assume, much like here, potential food sources would collect there, and eventually something would fill that niche.

There is no reason to believe. It's generally accepted that it's unlikely for there to be no life given the size of the universe, that's all.

1-4, skip 3.

How's that cynicism working out for you?

1) they are in a part of the universe so far away that we can't even spot their local group of galaxy

2) they developed and died millions of years ago, or will develop in a future so distant that planet Earth will no longer exist by then

3) their galaxy is exactly behind a bigger object (another galaxy or a star cluster), so we can't see each other

4) if, in theory, we can see each other, then in practice our technology is so different that we'll both dismiss any signal arriving as useless noise

5) if their signals are clear, we'll not be able to decipher them

6) if we can decipher their message, then their instructions to build a big ass quantum engine necessary to reach them will result in the destruction of our planet because they were playing a dirty prank on us since the beginning kek

>it's unlikely for there to be no life given the size of the universe

a billion of planets with "life" in them doesn't imply that there is "intelligent life"

and even if they are intelligent, the probability that they can develop a civilization is very small; think about a planet with plenty of resources and a nice weather: those intelligent animals will likely end up being Africans

and then, Murphy's law:
there is life, and it's intelligent, and they develop a civilization, and it's contemporary to our own, and it's close to our planet, and... oh no, they get hit by a giant meteor

Level IV here. Mars was likely habitable in the past but radiation killed them off. NASA should send a rover into the caves to look for alien fossils.

>alien fossils

NASA can put them there before "discovering" them for another round of fake news

after the global warming hoax I'd trust the chinks more than the burgers in everything regarding Mars landing

>my post actually got deleted
mods you really need to pick up a book once i a while.

Where is the "I believe humans are the creations of outside aliens, which explains why Earth is the only planet with intelligent life on this solar system, despite the fact we should have developed more like Mars or Mercury, as this planet was terraformed with unmanned spaceships like drones but in the shape of meteors, which is why we are the only planet with so much H20 on this solar system, etc etc etc" level?

Janny isn't here to read, nerd, he's here to protect feefees.

level 3 here

>level 3 here
because it would be really cool

If you're just upboating cuz it'd be cool - wouldn't you go with 9 or 10? Or at least 7, if you scare easy... (Then again I suppose there aren't many sci-fi's where we find ancient alien ruins and it goes well for us.)

Going much beyond 'fossils on Mars' borders on ridiculous, and aliens zipping around everywhere definitely isn't cool.

The space squid theory is somewhat plausible I guess. We want to believe.

There is simple life everywhere in the universe, it will form where it can.
Intelligent life is a whole other question, not sure how rare that is. Maybe one race per galaxy.

Are you talking about panspermia?

I wanted to write a story about a system where intelligent life evolved on two planets with the technology just 500-1000 years apart.
Impossible coincidence but fun.

Cortez is like the Simpsons, in that he did it.

Who is cortez?

I really do hope you're just having a brain fart due to the current context.

Combine these two, and your outlandish coincidence suddenly becomes viable - plus you have the potential big reveal that this all about godlike aliens playing an elaborate game of "Sid Meyer's, Interplanetary Civilization".

(Though about half the board seems to think that's what's really going on here - at least during the summer months.)

II

>Level XI: The Goverment has lied to us stemming from secret societies stemming from at least Ancient Babylon to try and convice us that God isn't real, aliens are just demons and the Universe is truely as depicted in the Bible.

>option to decline

fixd

If aliens are demons why do they need space ships to travel around?

Well they aren't going to walk, dummy.