Astrobiology and the Search for Extraterrestrial Life - with Ian Crawford 

Finding intelligent life on Earth should be the first priority.

Ian is my Professor at UoL. He is easily one of the smartest and most knowledgable people I've heard speak on this topic. Very lucky to have him!

If a civilization is 1000 light years away and they started transmitting radio signals at the exact same moment we did, we still have about 900 years until our signals reach each other. That’s what a light year means. The distances involved in this search are so vast, it’s almost unfathomable.

The Fermi Paradox is not all that paradoxical when you consider the vastness of space and time that makes other lifeforms inevitable also provides plenty of room for our paths to never cross.

Mr. Crawford is very down to Earth so to speak in his assessment. Even negative results educate us.

So here's the thing.. until a couple of decades ago there was no evidence that other planets existed outside of our solar system..we've looked at the heavens for thousands of years and just now find exo-planets.. we could have easily concluded that these planets just didn't exist, but low and behold after finding the first one they now seem to be everywhere. I suspect the same pattern will hold for life in the universe.

Really enjoyed this seminar...would be interesting to sit down and speak with this gentleman!

Was drawn in by this man's alienesque appearance, stayed for the quality presentation

Easily the best presentation I've seen on this topic.

As a species, we have been here for 200,000 years only. We became communicative (radio signals into space) only 50 years ago. Through a number of routes (war, disease, climate change) we might lose the ability to communicate or become extinct relatively soon. This is not a huge window of opportunity for finding alien life.

Why do we think life can only exist with what we need to exist🤔

Thanks RI for getting the laser pointer on the slides - it's really important.

Arthur C. Clarke summed it up well. There are two possibilities. WE are either alone or we are not, both are equally possible and both are equally terrifying!

We don't even know how big the universe is. There's no way we're alone

finding extraterrestrial life will have the same impact as discovering the earth goes around the sun had.

I recall that, in the movie, Contact, Ellie Arroway, asked the alien, who was disguised as her father, "How many of you are there", his answer was "billions of us". We may be living in a Universe where we are either rare or unique ( which I doubt) or it may just happen that we ended up in a more sparsely populated part of our Galaxy. Maybe?

I wait for the day a rover on a planet finds a fossil or even better life itself. If this is found before I die I will die a happy chap!

Well, for one thing, SETI searches have not even reached within 100 light years of Earth. This galaxy is 100,000 Light Years across. Not to mention that a highly technologically advanced civilization millions of years older than us probably wouldn't be using radio transmitters.

I love watching the RI series of videos on youtube. Makes me wish I had shown an interest in science at school.

Wonderful presentation on this topic.

This is such a brilliant lecture! I've watched it several times.

One of the key contributors to intelligent life on our planet is the 5 or 6 mass extinctions that happened where near 90% of the species were wiped out bringing about another epoch or era. If the meteor had not struck the earth 65 million years ago dinosaurs would still be roaming the earth. They were on the planet for 300 million years

If, during telescopic and electro-magnetic scans of distant planets, we find evidence for microbial life... There will be more advanced life there in real time. The further we look, the more back in time we are seeing. Likewise, if we do in fact receive a signal from a distant planet, there's no guarantee that they are still there.

A thoughtful and thought provoking presentation. Thank you.

Around every star, there is habitable zone such as starting from Venus to Mars for our solar system.

Even if the equation looks bad for another advanced civilization, I suppose the positive note is that probability increases dramatically that there are many garden planets (or other) with some degree of evolution out there. Still plenty of exciting things to discover I’d say.

I appreciate all of this. Thank you. 🙏🏼

Great presentation

Finding organics on Mars in june of 2018 has given me much hope for finding some sort of life in the universe other than here on Earth.

Someone should have told Ian that it was going to be recorded and that the laser pointer won't work for the hundreds of thousands viewers outside the Royal Institution.

Mr Crawford is more rational than most people who speak on this subject, in that he recognizes that we know nothing at all of the probabilities that life will arise from nonliving material and that life will evolve toward intelligent beings, meaning those who can understand and control the electromagnetic spectrum. But I have two criticisms: First, he casually moves between the galaxy and the universe, an error most speakers on the subject make. There is no point in considering the universe as a whole, because hypotheses about extragalactic life are untestable. We cannot expect to find and study planets in even the closest large galaxy, M31, and the rest of the large galaxies are vastly farther away. Nor can we expect to detect intelligent extragalactic radio signals, because galaxies contain many powerful sources of radio noise and the power required for transmission of radio signals between galaxies is unfeasible. So the only interesting scales for searching for extraterrestrial life are the solar system and the Milky Way galaxy. Second, at the end, he does what most speakers on the subject do. Despite his admission that we have no scientific theory of the creation of life, or of the probability of intelligent life, we should nevertheless continue with SETI efforts just in case. In my opinion, this is a fool’s errand. There are two bases for searching for particular phenomena heretofore unknown. Either we have experience which suggests that we should look for something similar, or we have a good theory which predicts something we should look for. An example of the first is that we observe that our solar system contains several planets and a lot of other junk, and we have a good theory of gravitation that explains how such things form and behave. We have good reason to believe that gravitation is universal, so it is reasonable to believe that other stars will also have planets and that we might find evidence of them at nearby stars. So we have done. An example of the second is the Big Bang theory, which predicted the cosmic background radiation. Although it was discovered accidentally by men who were not expecting it, others were already thinking about how to look for it. Regarding intelligent life, we have very little to justify a search which requires a great deal of time and effort. We know of only one species, our own, which has mastered radio communication. We know that there are many special conditions which allow Earth to support our species, but we know very little about how those conditions are met, and nothing at all about how life on Earth originated. We know how to use radio, but we have only been doing so for 150 years or so. We have no idea how long an advanced civilization can last, because beings smart enough to use radio can also invent several technologies capable of destroying civilization. In summary, I do not believe there is enough evidence to suggest that there are so many advanced civilizations in the galaxy that we should expect to find evidence of them. Even if the galaxy produced hundreds of advanced civilizations, it may be that they do not endure long enough to be detected by other advanced civilizations. Searching for signals from hypothetical civilizations isn’t good science because it is not motivated by evidence or theory, but only by emotion.

Anyone who is actually interested will soon discover that ETs have been around for Millenia. It beggars belief that there are still people like this who just can’t look at it because it will totally upset everything they used to believe. Admittedly this is scary but “If you seek - AND actually want to know - you WILL find”. If ‘knowing’ would be too scary or damaging to you you will not be forced to know.

Apparently, the aliens have been hanging out with the US Navy.

It's far more likely that the universe is teeming with life, even intelligent life. Finding that life could take thousands of years especially with the way it's being looked for. Radio signals from most solar systems are going to be competing with far stronger solar and larger sources. Yes I know we have sensitive equipment, but the people involved are skeptical enough that they'll throw out almost every source. They're also looking for human like life and they will never find that unless some progenitor seeded the galaxy with human life which is unlikely.

Understanding biogenesis is key to reaching reasonable assumptions about life in the universe. Without that crucial knowledge, all can engage in is wild speculation that goes nowhere. Forget about looking on other planets - earth has life but as far as we know it's only started here once. If this planet is so perfect for life, why isn't it originating from scratch over and over?

Great Ian!

If they have been coming to earth for over 10,000 yrs. There lifespan must be very long, or there time travelers which means they could be from anywhere in the Universe...even Earth ! If its generation after generation doing the same things that's hard to imagine... do you think our children will follow in our footsteps and keep the same original game plan....forever??? But If there Time Travelers they could live forever I guess...

And dont forget that their L has to overlap with our L during the habitual time of the Universe

Always asking myself, why sci-fi authors considered aliens as a hostile creatures, on the other hand, many true scientists believed to establish safe connection between our civilization and others far beyond... Absolutely intriguing one. Life existing on other planets is a major issue among scientific community to the present days.

Are Man's preconceived ideas & attachments to outcomes regarding the types of life forms he's looking for, really the stumbling block to finding the forms who exist much closer than we think?

When I was very young, I always thought that other galaxies could be our own multiverses. That each one had an earth with human life all trying to find each other hoping we weren’t alone in this dark cold void.

I don’t understand why he says “four and a half thousand million” he even has a chart that just shows 4.0 and says it’s in thousands of millions. Why doesn’t he just say billion?

Very informative sir

Interesting stuff. Currently I don't think we could detect ourselves from proxima centura, because the emitted radio/tv etc are too week for our own radio telescopes.

This was a very well done performance and information wise, it was well done also. I have similar skepticism toward the likely hood of finding interstellar communicating life in our galaxy. However, I do suspect it is there or has been there or will be there. It is the vast distances and necessary time intervals for one civilization to find one another that may be the significent issue. It may be like two ships passing in the moonless night and neither has a candle burning in that tiny moment.

How many times will I be walked through or have explained the Drake equation in my life? It's frustrating. Can't they ever assume that those interested have likely had that explained many times. Every single talk about the search for alien life goes over this and the Fermi paradox. It's like having to repeat an introduction course over and over and over before any discussion of the topic can happen

It would be unlikely that Planet Earth is the only one with some form of life. Honestly, we can't get to conclusions when we haven't yet explored and searched the vast indefinite universe, it would be unlikely to give a solid conclusion to this question without proper exploration. Life goes on. We will know in the distant unknown future...

A concise and erudite lecture.

32:59 "150 years later, we're still at that boundary" (between knowledge and ignorance), as described in 1853, on the subject of searching for life elsewhere in the universe... maybe this talk should have begun with that conclusion ?

Where are the aliens? They’re flying around in the tic tac.

I find it odd there are people that ask where other life is. We have not really even made it out of our solar system, and the universe is unimaginably huge. People who go into this Fermi "Paradox" thinking don't have much imagination.

I think it’s interesting that I never see anyone discussing the unlikely coincidence that two different intelligent life forms would develop technologies that allow detection/exploration at the same time. Humans have only had the ability to communicate with radio waves for about 100 years. 100 years is nothing on a cosmic timescale. If the development of an alien civilization that’s close enough for us to communicate with was only a few hundred years behind us we would never know.

We haven't even found evidence of intelligent life on this planet...

If you think that there is no other life out there you are just crazy

The drake equation is completely missing the possibility that a civilization may have spread across the galaxy. In that case, just 1 civilization would be enough to spread eveidence all over the galaxy. And it would be a very reasonal assumption. I would expect us to do the same given enought stability.

Regarding the question how long a civilization lives: even if a civilization gets extinct it doesn't mean that all life on that planet also gets distinct so there are chances that the remaing lifeforms develop again into a civilization. Wouldn't this increase the probabilities of fi and fc?

Or you could ask people from Earth that have seen or had interaction with aliens.. These people include Pilots, Generals, Police, The armed forces, The general public or even people from the Special forces teams that are sent out to secure areas where alien craft have crash before the removal teams get there..

This should have been called "A review of the Drake equation"

If or when we do make contact with other civilisations just what exactly will benefit them?

A brilliant lecture! So clear, precise, articulate and informative given! This man knows his stuff inside out 👌👌

I believe that the universe is absolutely teeming with life. To me this is an almost obvious conclusion. Intelligent life however, is something that may very well be extremely rare. I do not believe that we are the only intelligent beings in the universe but I feel that it's very likely there are only 1-3 intelligent civilizations per galaxy. However, I completely disagree with the pessimistic lifetime of a civilization. I believe civilizations for the most part can last millions or billions of years. What's a very interesting thought is suppose there was at least ONE intelligent civilization that basically has no end and say they were at the point we are now, 1 billion years ago. Just imagine the kind of knowledge and technology they would have now. When I think of that, it really does give a little bit of credibility to those crazy ancient aliens guys . A civilization 1 billion years ahead of us would basically be like gods to us now. They could possibly be immortal, time travelling, dimension hopping, even things we can't even think of. Time and space could possibility be inconsequential to them. I meant to just write the first paragraph and suddenly I had the second thought and couldn't stop writing. I apologize if that second paragraph sounded crazy but damn it really does make a lot of sense to me.

They are in The Pentagon.

Thank you so much r

I like this one and the Stephen Webb talk is good

The great filter

Pretty ironic they had a Vogon do this lecture.

If you don't have time to watch the whole thing the short summary is (as with every scientific approximation on alien life): "Could be everywhere, could be nowhere. We're not sure."

Judging by the statistics of living species as we observe them here on Earth, the development of advanced technology is uncommon. So even if life is widespread in the universe, and even if intelligent species are numerous, it may nevertheless turn out that technologically-enhanced species are rare, and that our level of technological advancement is very rare indeed.

Well I just hope we find someone out there one day, just imagine that😐

Where are the aliens? You obviously haven't met my in-laws... _ba dum dish_

there are so many potential concepts to consider. perhaps the probability for stable earth like planetary solar systems is the rare factor, BUT once such a quite stable system does form, life is essentially guaranteed to form on earth like planets. Looking at our own evolutionary history does tell us so much though. like that 3 billion year gap of molecular life we could easily nickname "the great Filter". also important to note from our own planet..... we only have evidence that life formed independently once on Earth. thats kinda significant, given we had the BEST place for it to form and evolution shows a tendency towards convergent paths whenever possible. also important factor of Earth, we are a primarily oceanic planet in a warm stable place, with a magneticly active core so technically still a "hot" active planet.

A new factor to the Drake equation seems to have cropped up, phosphorous may be far more rare then we expected. This element is considered a necessity for complex life.

I've seen and heard the same variation of this same speech a hundred times in the last 50 years ..... wake me when you find an alien .......

There's hard evidence we have been visited many times by intelligent extraterrestrials (Recent US Navy footage, Disclosure Project etc) , so why are you still grivelling around looking for microbes? XD

A good question is how far can radiowaves penetrate space until they get incohorent and undetectable? Bc if technological life had evolved we would probably already hear it since it's highly unlikely that it would have evolved at the same time as did we. They would have been there for a long time probably, making the Earth already engulfed in thw waves. But they're not there, so it's either that the waves do not penetrate the space, or we're alone (technologically) at least to the extent to which they can.

Good talk, I'm very interested in this topic.

I am the alien, shutup. Talking irritates us.

The aliens haven't invented space travel yet and they are waiting for us to come and give them a ride. "Galactic Uber"--Elon is probably working on it right now.

Due to the vast distances that space travellers would have to over come to make connection viable it makes more sense that aliens who are visiting us now, from a distance mind you, must be time travelling from our future. Or, moving through a space continuum.

maybe you should read the book "Who Built the Moon". After all you search the galaxy for potential cognizable planets you don't just X the map and move on. A stocked supply base would be more suitable for when you return.

Ian Crawford surprises me> he says there is only one place with intelligence in the universe that we know of. This is correct. However, how much of the universe has been searched???? a little little tiny amount.

Brilliant man. 👍👍👍

Amazing

Mars’ core is way smaller than earth’s and that’s one main reason why life didn’t develop on Mars if that’s in fact the case. So Earth and Mars aren’t comparable in that sense. On the other hand and despite the latter, if there is evidence of some kind of life on Mars then the evidence of life in the universe will keep on piling on and on.

Given all of the technology humans have at their disposal, we have not been able to replicate a cell, or single cellular, creature from scratch. We can't even create protein chains from scratch. With all that, how could life have just "emerged" from nothing? It's important that we begin to take a broader look at this. It's not a complete study to only look at certain assertions and ignore others.

This is why I have computers running BOINC, project SETI@home (and one other project). Because in the miraculous chance (and it would be a true miracle) a technological signal reaches earth after traveling 10,000 years through space, we need to know. Anyone with a computer at home that isn't doing anything for a few hours a day can participate. Mine run full time, but on a fast pc, a project file takes only 2-3 hours to process. If all you do is one or two a day, it helps.

anybody know what the chances of random background noise forming a false signal - although it wouldn't repeat i know?

This is the second time I've heard that fp (f-sub-p) is being considered 1 due to discovery of exoplanets. I've heard The Milky Way has a 3-digit number of globular clusters made up of many Generation II stars (number ?). Such stars might not have planets, or only H & He planets due to low-metallicity, or the high-density of stars in limited space could eject them. Similarly supernova remnants might have lost all of their planets. So how many stars in the Milky Way are (1) in globular clusters, (2) Generation II, and (3) supernova remnants? If 1/10 of stars in the galaxy that would make f-sub-p 9/10 instead of 1.

First thing of note is that the stars almost certainly required for life are G and K which only account for 20% in our galaxy. If you want to say "sunlike" stars then it's 7%. I plugged these numbers into the equation with huge lifespans (100,000 years and 10,000 years) and I got 1152 civilizations and 1 civilization. You'd also expect that, if intelligent life was relatively common, 1 civilization would have colonized the galaxy in the past 10 Billion years. Now, maybe they died off and the remnants disappeared... but then if it were common, another would have done the same at some point and that pattern would continue, polluting the galaxy so to speak with more evidence. So it's not that there isn't anyone else, or there has never been anyone else... but it's also not as far-fetched as you might think to believe it's just us.

A ramped up version of the talk I heard at the local natural science society, with some inane audience members weighing in obviously cosseted by too much telly and look it can't get away from addressing existential loneliness when it tries as hard as this.

They are here and been here since at least 400 thousand years.

How are we alone isn’t that the answer Isn’t so painfully obvious that we are literally the last man standing. Figuratively and LITERALLY speaking how is this a question to this day.

If as scientists believe nothing can travel faster than the speed of light it would take a minimum of 4000 years to reach our nearest star. Most things in our galaxy are millions of light years away making any meaningful study or association with alien life forms if we can find any a fanciful goal. A more interesting study considering we were single cell life forms a billion years ago, might be to study our likely evolution over say the next million years. Would we be able to recognise ourselves?

Just because we look up and wonder what's out there doesn't mean there isn't planets full of weird and wonderful creatures that aren't arsed what's out there.

I would go with bacteria in the universe. Intelligent life from running down deer and avoiding the competition to star ships. We are a rare indeed.

There is that little thing that we are looking for our own self in the universe, the life that we know on Earth, not that can be helped because that is the only life forms that we know. What kind of life could exist in for any practical purpose infinitive universe is beyond anyone imagination, maybe we just not learnt yet to ask the right questions.Our scope of space explorations is so little that any conclusions about existence of other life in the universe are of course pure speculations, Nothing else left than to keep trying eh.

why we dont have contact with extraterrestrial civilizacions? clearly we are isolated, but can we request to break that isolation? who is in charge?

Yes and what about the UAPS involved with the US Navy fleet...

5:00 Life is not currently flourishing on the surface of Mars. That doesn't mean life hasn't flourished before. In another billion years when the sun has become hot enough to boil the oceans, and strip most of it's atmosphere away there will be very little life left on Earth. You would never say life was flourishing. In fact, the Surface of Earth may look a lot like the surface of Mars today.

What did wallace base his conclussions on.