What a planet needs to sustain life | Dave Brain
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- čas přidán 3. 09. 2016
- "Venus is too hot, Mars is too cold, and Earth is just right," says planetary scientist Dave Brain. But why? In this pleasantly humorous talk, Brain explores the fascinating science behind what it takes for a planet to host life - and why humanity may just be in the right place at the right time when it comes to the timeline of life-sustaining planets.
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Wow, looks like TED remember why they became popular in the first place. More of these please.
TED provides nourishment for hungry minds.
Glad someone's finally talking about the relationship between magnetespheres and habitability on planets.
his audience was unusually lighthearted
TEDx vs TED audiences
He was a pretty funny guy. And he says jokes in a serious tone which makes it funnier in my opinion lol
I seriously got chills when I saw the river carvings on Mars....
His name is Brain, therefore he is smart. QED.
Quantum Electrodynamics?
Shrey
No.
+Shrey Quod Erat Demonstrandum
El Brayan ;)
I've read some of Brian Greene and liked it
Dave reminded me today that you can have fun with the science you do and still have a great impact. Congrats on a great talk and I am very glad I was here to listen:)
confirmed, all life needs moose to survive.
Nah mate. We need mousse. Chocolate mousse.
lol....Indeed. Flowers, moose, and vegetables....that's _all_ anyone needs in life.
And Mike Phelps...what about hair mousse? You know, for windy days and such...
This was the best seminar in a while.
Yeee pretty good tasting semolina
Nate ☺
this dude is pretty hilarious and informing at the same time
I gotta give it to the guy he was by far the best Ted talk speaker I've heard in a long long time maybe the best period his presence and showmanship was awesome
This was old school TED fantastic!
Fantastic Job he kept it simple with great clarification 💯💯
So uplifting to know, we have guys like these working on such important things. Actually reminds me of "Interstellar".
Always making *Valuable* videos. I like it♡
Hey flat earthers. Trigger warning: The earth isn't flat.
You really told them!
Our eyes are round, that's why we see the earth as round. But in reality, its flat! Checkmate atheists! #BattlefieldIsBetterThanCod
THE EARTH ISNT FLAT ?!?!!?!? WTF !?!?!??!?!?!?!?!?!!?!?!?!?
I dont believe earth is flat but girls do have flat chest
I think you time traveled back to the wrong era. You might wanna go further back in time if you wanna speed up advancement in knowledge of space and the universe. You're one step closer to your location when you find that there is no Internet.
Thats a really nice presentation. The last part of the presentation is golden.
a few times I thought he was going to cry out of emotion
I thought the same too. His talk is very engaging!
Fantastic talk!
One of the questions that he did not investigate was why the large amount of water that is found on this planet. It is not just moist but sopping wet and it came from "Nowhere".
Yeah
this guy is an amazing talker
A question! If there is a discharge system in Mars why then there is no life?
Moving of material in subsurface makes the magentic field, the absence of this move could remove this field?
This is pretty simplistic thinking. If fact, the worldwide scientific community has come up with a list of over 100 + specific planetary conditions that must all exist together it order to support life. The chances of all 100+ conditions aligning diminishes the likelihood of life by an infinitesimally small fraction of the number of planets theorized to exist in the universe. In fact, it may even lower the possibility to a crap shoot so low that its not unreasonable to being to think "life", like ours, is a very rare mathematical coincidence that may not be repeating anywhere but here, and for only a short time in the universe.
howie weed science has proven that everything didn’t happen by accident all the factors are so precise that it requires more faith to believe it all happened by accident than to believe that there’s a Creator to our universe
Great talk! Thanks!
i love this talk!!
He's a great speaker. Hope sci teachers are like this.
I love this man
loved this Ted talk, funny and interesting. who is the one giving this talk?
Our daughter just introduced me to TED. I think I will like him.
I love this man's sense of humor😂
Great topic ☀️
im really glad we are here too
Excellent.
This is terrific
He didn't mention location, size and rotation of Earth. Actually there are 200 parameters (still increasing) needed to accomplish to have a another Earth.
Lets say you have 0,1 chance to fullfil 1 parameters. There will be 200 zero. So chance to meet another earth literally almost zero.
Love this guy!
Great TED!
I like his sense of humor.
It is really nice, that you have defined what life needs to exist, those 3 criteria - energy, nourishment, water. Great! Now define what LIFE actually IS, so we know what we are actually looking for. I hope you don't think that there is just "biological" life outhere?!
There some few interesting lines from wiki:
The definition of life has long been a challenge for scientists and philosophers, with many varied definitions put forward. This is partially because life is a process, not a substance. Philosophical definitions of life have also been put forward, with similar difficulties on how to distinguish living things from the non-living.
Biology
The characteristics of life
Since there is no unequivocal definition of life, most current definitions in biology are descriptive. Life is considered a characteristic of something that preserves, furthers or reinforces its existence in the given environment. This characteristic exhibits all or most of the following traits:
Homeostasis: regulation of the internal environment to maintain a constant state; for example, sweating to reduce temperature
Organization: being structurally composed of one or more cells - the basic units of life
Metabolism: transformation of energy by converting chemicals and energy into cellular components (anabolism) and decomposing organic matter (catabolism). Living things require energy to maintain internal organization (homeostasis) and to produce the other phenomena associated with life.
Growth: maintenance of a higher rate of anabolism than catabolism. A growing organism increases in size in all of its parts, rather than simply accumulating matter.
Adaptation: the ability to change over time in response to the environment. This ability is fundamental to the process of evolution and is determined by the organism's heredity, diet, and external factors.
Response to stimuli: a response can take many forms, from the contraction of a unicellular organism to external chemicals, to complex reactions involving all the senses of multicellular organisms. A response is often expressed by motion; for example, the leaves of a plant turning toward the sun (phototropism), and chemotaxis.
Reproduction: the ability to produce new individual organisms, either asexually from a single parent organism or sexually from two parent organisms.
Alternative definitions
Entropy and life
From a physics perspective, living beings are thermodynamic systems with an organized molecular structure that can reproduce itself and evolve as survival dictates.Thermodynamically, life has been described as an open system which makes use of gradients in its surroundings to create imperfect copies of itself.Hence, life is a self-sustained chemical system capable of undergoing Darwinian evolution. A major strength of this definition is that it distinguishes life by the evolutionary process rather than its chemical composition.
Others take a systemic viewpoint that does not necessarily depend on molecular chemistry. One systemic definition of life is that living things are self-organizing and autopoietic (self-producing). Variations of this definition include Stuart Kauffman's definition as an autonomous agent or a multi-agent system capable of reproducing itself or themselves, and of completing at least one thermodynamic work cycle.
Biophysicists have commented that living things function on negative entropy. In other words, living processes can be viewed as a delay of the spontaneous diffusion or dispersion of the internal energy of biological molecules towards more potential microstates. In more detail, according to physicists such as John Bernal, Erwin Schrödinger, Eugene Wigner, and John Avery, life is a member of the class of phenomena that are open or continuous systems able to decrease their internal entropy at the expense of substances or free energy taken in from the environment and subsequently rejected in a degraded form.
So tell me, does your search for signs or markers of extraterrestrial life also include all those general definitons of life (not just life as we know it)?
I think that there is no point of inventing things like "habitable zone" - except habitable for some finite number of known earthly species, because Universe may be (and I am sure it is) much more habitable then we think. Maybe not necessairly habitable for us, but very well habitable for other forms of life that we have even ever dreamed of.
Thank you.
And thats a bold statement saying that other planets dont have a magnetic field like our considered we have never been to those planets
Great video very interested story
Great!
Informative
Why is life defined by temperature, nutrition and need of water? What if life somewhere around the universe didn't need water? Or they didn't need the same temperature to survive?
We look for life as we know it. If we would look for life as we don't know it, we wouldn't know where to look.
Simon Farre Yeah, haven't even thought about it in that way.
it's actually theorized that there may be methane based organisms on Uranus (I believe that's the right planet). so rather than having lipid bilayers they'd most likely have methane bubbles for structure
Because they're scientists, not sci-fi authors.
At the very least you need some liquid suspension, and you need complex molecules.
The latter are almost ubiquitious. Carbon is the only element able to form almost arbitrarily long molecules which are chemically active in a timeframe shorter than milliards of years.
The liquid need not necessarily be water, but it has to be at a temperature that allows these chemical processes to happen, and water is the most common compound molecule in the universe.
So we are looking there because it is the best change of finding something.
Yet I am still somewhat hopeful for magnetically encoded genes (rather than chemically) in silicium (which can also form complex molecules, albeit at far lower temperatures), though I won't hold my oxygene-rich breath.
Very good.
There are an incredible number of parameters required for complex life to exist on the earth. Here are just a few:
1) Goldilocks distance from our sun
2) Goldilocks place in the Milky Way - too far in and too much activity from quasars, pulsars, black holes, asteroids, etc.
3) Our large moon keeping axis tilted so seasons occur.
4) multiple large outer planets to gather up most of the asteroids with their massive gravity
5) Goldilocks amount of plate tectonics to release necessary ingredients for atmosphere, but not too little or too much. So, we need earthquakes and volcanoes and we have just the right amount.
6) Inner iron core for electromagnetic field to protect from solar radiation and burn up many smaller asteroids.
7) single star system in solar system as dual stars will disrupt seasons, tilt, etc.
8)Stable planetary orbits so larger planets don’t cause chaos by having irregular patterns.
9) Goldilocks sized ocean - too big or little and atmospheric content won’t have proper mixture of elements.
10) Goldilocks planetary mass within parameters to hold ocean and atmosphere
11) Goldilocks kind of galaxy. Spiral galaxies are best as they have sections with fewer stars and activity in their arms.
There are many others. Some lists are up to 200 such features. And without any one of them, we wouldn’t be here. The combinatorial statistics of multiplying one such factor by another by another leads to infinitesimally small odds for finding another planet with complex life. Moose are very rare indeed!
And as the parameters for life are not just the three broad things mentioned here, but all the long list of other things to prevent life’s annihilation one way or another, it doesn’t matter that there are 40 billion planets with these three features. They are still very unlikely to have complex life due to all of these other factors.
That is, if the universe and life are dependent upon chance. But since we are here and shouldn’t be by the odds either, it appears there is some sort of teleology inherent to the universe.
Now SETI and Dr. Brain benefit from not sharing the actual statistics because they wouldn’t receive much funding with odds so against the chances for life. It therefore behooves SETI and scientists like Dr. Brain to advance the legitimate conclusion that the universe has an element of teleology which tends towards increasing the likelihood of life.
This, however, would be objectionable to many in positions of power in the scientific community as they unfortunately do not wish to admit
teleology as a feature of the universe.
Thank you for your reply! Your reply save me the time in trouble of responding. This talk may be entertaining, but it is so far from being comprehensive that it is ludicrous. The probability of finding other planets of meet all of the criteria required for intelligent life, are so infinitesimal that it is staggering. What concerns me is the number of people who think that this is actually accurate. TeePee
excellent
This is a genuine question and not a criticism. When we speak about complex life or just life, isn’t he speaking about life as we define it? What about a possible life form, which requires nothing that earth life requires? Why not conceptualize a form of life so different from ours that we could not exist on the same planet? This has already happened with earth species when life has been found in places where it had been previously supposed that no life could exist. Overall, a good Ted talk - I just wish people would preface such talks with the caveat of ‘life as we currently understand it to be’ or some such words. Thank you for an interesting presentation.
🌲🌝☘️
He did say life as we know it
Shantanu Sinha. apologies, I obviously missed him saying that. Must pay more attention in future. Thank you for being more observant than I am.
🌲🌝☘️
Very cool
Fun and interesting!
good talk and he's funny
Wonderful speaker. I'd love to hear him speak about this content a bit more indepth. I study Kepler's ELW findings quite a bit as well.
Nice job
the way we define life is relative to us. other types of life and what they would need to live arent even fathomable to us!!
but life as we define it must have some properties, otherwise it is not really alive. Viruses are not thought to be alive because they lack some of those properties.
Energy is absolutely needed, i think we can all agree.
Nutrients are absolutely needed, because life has to be made out of something, and there are a limited number of reactive, common elements out of which it could be made.
Now, water. We think, and here comes what you said into play, that water is absolutely needed, because from our frame of reference, from our biological makeup, we can imagine no way that life could exist without some sort of medium, which allows the quick interaction of energy and nutrients. that medium does not have to be water, but most other liquids are too rare, to destructive to the flow of nutrients, i.e. too hot, or the flow of energy, i.e. to cold. metallic liquids dont mix well with other things. some carbon molecules are liquid in the right temperature range, but they are too uncommon in the universe, we think.
so our current understanding really only leaves water aa the medium.
within these parameters, life as we understand it could develop. however, im not disputing that other life could exist. maybe the interactions of gas molecules in large clouds which are left undisturbed could develop sentience. it however is ununderstandable for us how something like this or similar to this could happen, and even if it did, we wouldnt necessarily even be capable of detecting it.
until such a time as we can, let us just focus on life as we do understand it.
*goosebumps*😍😍😍
I can't belive this, my brain is just like WOW!😶
What if "Life" existing in other planet bodies is in a very different form to ours on Earth? We're human and we're searching for something like us out there, something confined by our own foundamental experiences. So what if they're not living on the same conditions as we are, but something beyond, unreachable and inexplicable to our terrestrial comprehension? Are we too rash in concluding that there's no other "habitable planets"? Just wondering :)
I as Mr. Ahmed Ibrahim Hassan haji Ali living in Somaliland government saying: we are lodged on Earth by no choice of us. It is very condusive, comfortable to sustain our life. It is crystal blue, manificient and beautiful. Let us we humans maintain it, and try not to corrupt it for there is no elsewhere to go at least in the near future.
His a really good teacher😆
At first I thought this talk is pretty standard fare discussing the trinity of things needed for life i.e. liquid water, energy and organic components. But then it caught me offguard about magnetic fields, I knew Mars no longer had a magnetic field but I had no idea that Venus didn't. It makes sense that Mars doesn't because it's smaller than earth so the planets core cooled significantly faster and it no longer produces one,but Venus is Earth's twin so why doesn't it have a magnetic field? I wish he had gone into more detail about that
Watching this video for a class and a little confused, what are two explanations for why the atmosphere on mars changed?😭
What a planet does not need to sustain life?
Humans.
unfortunately, jajajajaja.
Yeah, he is right... as proof, when writing in English it's hahahaha... no one cares how spaniards pronounce j or what jajajaja means.
+Emm N. I'm from Washington state
they also don't need any other animal.
Then who is they? The trees? Apparently theyre not concious. So "they" cant be a they.
The scope of this talk is a bit small. Life could be defined as a selfreplicating pattern that needs energy and matter to sustain itself and it's descendents. To define life as only what is known on earth just shows how stupid and selfindulgent we are.
There are so many planets to choose from, so we can just as well look for life at planets exactly like ours
@@stigcc That blind hope, though. Who does not want to see a new planet with life? Scientists now say it is next to zero probability to find an earth-life planet.
And information!
Which are the 6 chemical elements that make the food,the nurishment?
THIS GUY MADE ME LOL SO HARD!!!!
I hadn't heard of the hypothesis that the magnetic field may indeed be causing the escape of atmosphere. I'm sure there's good hypothetical science to it, but sounds doubtful to me unless they can prove it. Evidence, as I understand it, seems to point at Mars' atmosphere once being protected by a magnetic field which has since faded as it's core cooled, allowing the escape of it's atmosphere.
Wow! The thing i can retain from this talk, "EMF". so that's really a smart idea to implement suits and future spacecrafts. So we don't lose energy in space explorations or travels. Maybe it's us that's going to populate life or spread life in the universe. We just need to start build those robots that going to do the job for us. I mean Mars it is not red for nothing there plenty of iron there already. No wonder there so many 4x games on space exploration. it's amazing how the word hope rests upon science fiction. Just saying, thanks for the video. ..
Those are the factors that support life in this world as have been studied in science. However, there may be other things that may have not been considered or probed such as the presence of chi. Perhaps there is no chi in the other planets that had been probed by humans. It may be waste time and resources to further send rocketships in search of habitable planets.
Mars also shows, if there was life there, it was made extinct, and we should learn the lessons that Mars teaches us. We too, can go the way of Mars if we are not careful in the management of our planet.
life *as we know it*
Any one noticed the two in the front row 0:40 - Dead stare while the other looks over as if to say " What are they laughing at?" LOL
@00:50, the laughter and the image don't go together.
Im also glad im in this planet....
Why would TED or y'all upload this soo late?
I imagine this person as my teacher , i would not escape any lesson ;)
magyar feliratot kérnék szépen, pleeezeee! :)
It is beatiful
💎
What a planet needs to survive based on what we know now.
So those planets are close enough to reach them? Thats cool cuz I thought that space is big and we might not be able to produce enough fuel for reaching closest suitable planet.
Considering that Venus has a really thick atomospher, while not having a maginetic field, it should be enough evidence to suggest that a magnetic field isn't needed to keep one. It seems like it's much more about mass and thus gravitational pull.
Ofcourse this data is interesting, but I doubt it will make us reevaluate which plants could have life.
good point but apparently venus is actually dumping a lot of atmosphere ever day which is consistent with the idea that solar radiation is affecting the atmosphere so taking that into account there can be other explenations
Unless Venus used to have a atmosphere twice as big. In which case is actually really useful.
This presentation narrows down the necessary parameters for planetary life to an extreme degree. There are literally hundreds of parameters currently identified, all of which are necessary simultaneously for a planet to be life-sustaining. If we give each one of them a super-inflated one-in-ten chance of occurring on a given planet... we are looking at probabilities so small that the negative odds vastly outweigh the number of estimated planets in our galaxy. From the data we currently possess, it appears that the existence of other life-sustaining planets is, if we are being honest, a mathematical improbability which is so vast that many are now suggesting that the term “impossibility” is in line with the science.
While I enjoyed the presenters excitability, he is simply wrong to suggest that life sustaining planets are likely to be found throughout our galaxy.
i just think different environments would sustain different life :/ or even life that isn't even what we define as "life", maybe those forms are not matter nor energy. and human concepts like intelligent lifeforms may not even apply at all
***** yeah i understand :) but it seems like no scientists have ever acknowledged this part of the study. even if we can't comprehend it maybe machines can
***** yep ofc i know but they are not even addressing it, at least they address that there is this possibility
The Answer Is More Life!!!!
Why is it that speakers always sound out of breath
No governments, no corporations, no monetary system, no global system based on psychopathic competition.
A non-hierarchical system based on cooperation, access to knowledge, science, technology, sharing and conserving resources.
you just described a theoretical system that will never work
... on Earth, but the same system might already be in place somewhere else, an alien race which, through its superiority, will wipe us out for being this lame.
+Emm N. No. That wouldn't work for anyone. What kind of 5 year old thinks the entire human species will just work together for "progress?" It makes no sense.
Jeremiah Brand Well, if you argue with "what kind of 5 year old"... then it stands to reason you're not mentally equipped to understand the answer.
***** I have to disagree... see, in recent times of war, russia-us-syria-other islamic states etc, the scientific community doesn't care about embargoes and politics, they work together nevertheless, from US to China, if the gov doesn't hawkeye the project, they are willing to share data and get different prespectives and ideas on how to move forward. It's not a lot but it's something in that regard as Goodguy001 layed out. Humans, but which ones? Yes, the frustrated ones, the ones who never achieve the intellectual threshold needed to do good in this world, those are the ones who meddle and try to stop a unifying progress through self serving politics and governance. This only holds as long as the foundation of society, the working and middle class, allow to be lied to, since these frustrated meddlers never achieve what they promise.
this guy should do standup
Wouldn't other liquids be able to flow and carve riverbeds? Why does it have to be water?
Yeah true i forget what planet it is but one has liquid methane on the surface. I wish i could remember what planet it is.
The energy is not getting in so much as more energy is being reflected out. Hence the Arora is brighter closer to the planet the cores power is reflecting it out! Seem very clear! The EMP from the solar flares are being pushed back from our magnetic cores charges
He downplays the necessities for life and makes it seem too easy.
I've been wanted to go to a ted talk conference, but I just found dead out tickets for an application is around $1000...
maybe I'll get tickets in the future to take my son and have him educated by I think it would be a great experience
Flying bears are funny and dangerous.
this guy is so funny : D
These are the things that are required to sustain life. (Energy, nourishment, and water.) What are the requirements for life to come into existence?
Good question
To use Mr Brain's analogy, if mama bears porridge was once hot, is there a chance that daddy bears porridge may one day be just right. Baby bears porridge may be too hot by that time and so then it would only be logical to then switch.
This is good to learn English.
Yeah!
Without the moon stabilizing our planet we would not have life. Without our location being in the Goldilocks zone we would not have life. Without Jupiter acting as the solar system's vacuum cleaner pulling meteoroids away from us so we don't get clobbered we would not have life. We need so much more than these three things mentioned in the video.
That's so many coincidences that makes me believe there is a God.
Wait. We have discovered traces of living microbes on mars. It may not be alive now but it once was.
More like what a planet doesn't need to sustain life, which is humanity.
It's a shame you didn't do the talk after you had the data from the probes, then we'd get an answer.