Do Habitable Worlds Require Magnetic Fields? | Dave Brain | TEDxBoulder
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- Опубликовано: 8 сен 2024
- "I'm glad we're here" is the start of this talk by Dave Brain. What does it take for a planet to be hospitable for life? On how many planets could we use a compass to find north (and what does that have to do with it)?
Dave Brain is an assistant professor in the Laboratory for Atmospheric and Space Physics and the Department of Astrophysical and Planetary Sciences at the University of Colorado. As a planetary scientist, he studies the interaction of unmagnetized planets such as Mars and Venus with their space environment. This topic is exciting to him because charged particles and magnetic fields from the Sun are believed to have fundamentally altered these bodies over the past 4+ billion years. By studying processes that occur there today we hope to unravel how these and other planets evolved, and why their atmospheres are so different from our own. He is a Co-Investigator for the MAVEN mission currently orbiting Mars.
This talk was given at a TEDx event using the TED conference format but independently organized by a local community. Learn more at ted.com/tedx
1) molten core / vulcanism (creates magnetic field and eventually kicks of plate tectonics), plus supplies organic compounds (hydrogen sulfide, arsenic...)
2) water
3) continued plate tectonics (requires water for subduction)
i think these are all the ingredients that create temperature gradients and a dynamic enough environment to form the first complex molecules from which life can originate.
But remember Jupiter's core isn't molten core but a frozen hydrogen due to high pressures....the solid core acts as superconductor creating can Allen belts
But why ? Don't forget about Moon. It is Moon who make our core in liquid state. If our Moon would be smaller like Phobos and Deimos, we haven't magnetic field.
Interesting ramble but it didn't really dwell on answering the title question.
yes a misleading tittle but a very interesting study.(he said they dont have the solution yet, but they send spacecraft to orbit 3 planets for more study, one of them is mar he did directly state the other two, he did mention jupiter and venus doe)
I wish this guy had been all of my science teachers. Humor, wit, and enthusiasm. My teachers in high school were ...tired. College wasn't much better.
You wish your teachers made loud sloppy saliva noises with every word they spoke?
He lectures my astronomy class like this too 😂
Edit: he did the "dancing" thing last week
I came here to find out whether a planet needs a magnetic field in order to be habitable. I was kinda disappointed that I didn't get an answer.
Mars had a catastrophic collision, it's what popped its core and we see it all over the surface, you're not even wrong!
Io is highly volcanic which implies that portions of it are the correct temperature for life. Io may be a bad candidate for life. Around other stars, we may find moons that are the wrong distance from the star, yet still have habitable areas.
The ocean moons are the best candidates here, but I think we should only use mars for a pit stop. Like a stepping stone to beyond our solar system
If The solar wind is blamed for the loss of atmosphere on Mars. How does one explain the extra thick atmosphere on Venus? Both planets lacking a magnetosphere.
Venus is bigger. More gravity, better at clinging on. Perhaps also, it's generating enough atmosphere from processes at or below ground level to make up for any losses to solar wind.
I thought Venus was slightly smaller than Earth. That's why Venus didn't have quite enough mass to create the required internal dynamo to produce a magnetosphere.
@@randynelson2265 The difference is fractional. Mass is clearly not an issue all of it's own. Earths molten core is radiactive and I think that's what's sustaining it. The magma keeps flowing and that's what keeps our magnetosphere running.
Venus might be cold, or made of the wrong materials. I'll have to look it up.
Three conditions are required to sustain a magnetic field: 1) The presence of liquid metals, 2) Convection currents driving the liquid metals toward and away from the core, 3) Rotational forces driving lateral movement of the liquid metals.
Venus doesn't have an endogenous magnetic field because it is rotating too slowly; its day is 5,832 hours (243 earth days) long, and as such the liquid metals at its core are not subject to enough rotational forces to generate a magnetic field from inside the planet.
The Martian mantel is very rich in hydrogen, which interferes with the ability of heavier elements like iron and nickel to sink into the Martian core, thus stalling the convective currents also necessary to generate a magnetic field from within. If we could come up with a way to remove this hydrogen, Mars' magnetic field could theoretically reboot, which would be a necessary first step to terraforming the planet into a habitable world.
The liquid metals at Earth's core are subject to enough rotational and convective forces to generate and sustain a magnetic field, which is the main reason we have one while Venus and Mars do not. The radioactive elements in the Earth's mantel and core generate heat as they decay, and this helps keep the metals fluid enough to churn up a magnetic field, but radioactive decay does not itself directly contribute to Earth's magnetism.
Venus has managed to hold on to its atmosphere for two reasons: 1) Its extremely dense ionosphere interacts with solar winds to generate an exogenous magnetic field which, though relatively weak, deflects a percentage of the sun's charged particles away from the planet. 2) Venus' atmosphere is comprised mainly of heavier gases like CO2, and contains thick clouds of H2SO4, another heavy and energy-soaking molecule. Since Venus' gravity is comparable to Earth's (91%), these dense atmospheric gases are heavy enough that they require a lot energy put into them before they can escape Venus' gravity well. Despite this, Venus is still losing atmosphere; it's simply that it's an extremely dense and partially protected atmosphere comprised of heavy gases that are difficult to eject.
I think all efforts should 1st be concentrated on developing a permanent station on the moon. It can be safely manned in 6 month shifts that has already been proven possible on ISS.
Then it is clear that the key to travelling long distances in space in reasonable time is nuclear propulsion. The nuclear powered spacecraft cannot be developed on earth but moon can be used for that purpose. Once that is achieved then such spacecraft's can be used to move ice commets and a magnetic shield to Mars and only then we can start sending equipment and humans to Mars. To do that before is a waste of money and more importantly TIME. Reaching Mars now is was exactly the same mistake we made with the moon; getting there to early to do anything useful.
ISS should have been the 1st step.
I like to know about any objection or flaws in the above plan.
I am a little late but whatever you are talking about makes sense to me.
I thought this video would give answers, not just elaborate on the question in the title.
I agree! I have seen many of these type of talks, and while they are fascinating, none of them ever gave solutions or answers. They are always in the process phase of research. None of them will give us the anticipated information. But what can you/we do? Think, think, think. Be creative, and figure it out yourself, and share your best knowledge, so the rest of the world has a chance to became a more informed and better place. This is all we can do, learn from each other.
U2 little things
We dont understand life enough to have even an educated guess...all we have is sample size of 1....
You just saved me ten minutes (double speed) thanks :)
Thanks. I didn't waste my time after the first 3 mins and reading the comments. I could pose interesting questions all day long that I can't find the answers to, besides my own theories and imaginings. The eternal WHY? And WHY NOT? and IF? AND....The 5 W's and the H....
i wonder if we could (in the somewhat distant future) restart mars' magnetic field?
nuke the core
The first assumption is that life can only be carbon based, why should that be the case?
The physical deterioration of astronauts bones and brains is a clear indication of the effects of extended time in weightlessness.
I always thought about the magnetic shield protecting our atmosphere, but the sail theory is sound. I wonder what geologists and paleontologists say about our atmospheric pressure and composition in the past.
Ganymede also has a magnetic field. Also within the magnetic field of Jupiter. Is it habitable? It has a thin atmosphere. Could we make it habitable by redirecting one of the smaller moons of Jupiter to strike it and warm it up? How long would a resulting atmosphere last?
i would think so to protect from Radiation
Can we use electrically generate fields to divert the charge particles?
Yes. We only need several atomic bombs exploding every second to achieve that kind of magnetic field :)
that means its possible but impossible :p
nope won't happen ever not with our species. our species our planet all that is unique but primitive in existence. we don't even fit the criteria for the type of existence that could generate technology that could do such things...... impossible in the truest sense of the word impossible. if anything was truly impossible that's the one.
Much much more money into space science please.
Theoretically it is possible now to build spacecraft that can reach 80% the speed of light to reach other star planets in one life time, but it is a one way trip because the 5 year minimum would make a return of 10 years be over 40 past on earth because of relativity. If a 15 year trip out was taken, on return hundreds of years on earth will have passed. So any space travel will be one way into an unknown destination.
SETI has been looking for decades, we are alone.
This all considering it's life as we know it. With billions of stars, planets, solar systems. I've always believed life outside our planet will almost certainly not live the way we de, let alone have similar anatomy
Garrett Garvin
extraterrestrial life (if i exists) wll have to adhere to the same laws of natuer as the one on earth: a) it will need energy (and thus very likely a potential gradient), b) it will required a liquid phase, as otherwise the reactions can't take place an it's ot alive but dead. This phase doesn't have to be water, but due to the elementary composition of the universe everything else is highly unlikely, c) it's gonna be based on carbon. No other elements shows the required properties. No matter how much "out of the box thinking" you'll do .. you won't get away from these basic requirements.
Answer is YES.
Somebody get this guy a glass of water
Excellent 👌👌👌
Life? No. Complex life? Yes.
But how big is a postage stamp size piece of the sky?
It would have been so wonderful to have seen a verdant Mars.
It probably wouldn't have had plants or anything. I doubt Mars could ever have had a significant amount of nitrogen or oxygen in its atmosphere.
The crucial phrase, which he is not using is "life as we know it."
My point exactly
There is no other "life as we don't know". Life needs WATER. Every life. Then there are few atoms (oxygen, carbon, nitrogen, hydrogen, phosphorus, sulphur). And this is not because these atoms won a lottery. This is STRICTLY because of their energetic bonds they can create. So anywhere in the Universe whatever life exists it will use the same building blocks and the same idea of DNA chains.
...would you settle for “life as we define it”
I think this needs to be proven, one way or another :)
now we have clue of live in venus
yeah!!! we have found phosphine
We will know one day but maybe we will need supercomputers to build the hardware to find out. Also, we will have to become richer and more developed to afford the hardware and manpower or robot power. With so many living in poverty only a few nations are capable of space exploration.
Is that John Boy?
Astrology is an old trait for most indians .. our lives r intertwined with the stars
Yes. Never have I seen this question be acknowledged. Magnetic energy is key to all life other than the sun of course... I'm not even a scientist but im confident in my statement I just put here... ,,!,,
I don't know that it is accurate to say that all the elements necessary for life are present in sufficient quantity everywhere, or even that such is common. How about phosphorus (ATP).
He was hoping someone would be able to answer the question in the comments section.
Without a magnetic field a magnetosphere wont exist. The magnetosphere provides a protective shield around the planet and applies radiation pressure to the surface that allows the gases to be compressed to a usable level. The solar wind is a plasma made up of positive ions and electrons. When this plasma interacts with the magnetic field it causes a lorentz force on the ions and electorns causing them to travel around the planet in different directions one west one east dependiing on the direction of the field.
If you want to terraform mars the first thing to do is create a synthetic magnetic field using large superconductive coils. This will create a magnetosphere and pressurize the atmosphere. Then send the CO2 to Oxygen generators. When the oxygen level is high enough and the CO2 below 5 percent then you can safely travel there and attempt colonization. I would determine if the planet has a magnetic field before considering a visit. No magnetic field will mean its not habitable.
How stable that sistem must be, to stay here for so many billions of cycles.
Spikes in the brain
Require? Probably not but a magnetic field would be highly desirable
love the jokes...finally some one real!
Great presentation and subject. Do you think it's earths turn to loose magnetic field? And here's a wild speculation... The earths magnetic field is diminishing, resulting in more solar radiation? Are governments deploying reflective metals to compensate for earths weakening magnetic field? To reflect rads. Thank you.
Well, we are sister planets with Mars so it would seem we're next in line.
jean cary Our field is weakening because its getting ready to flip. After it settles it will strengthen again. The north magnetic pole is racing towards russia currently.
Magnetic flipping, the new Y2K bug.
Or, those "river-beds" on Mars could have been formed in an instant by electrical discharge..
Yeah, or a fart from a unicorn while we're at it. You'd need a prolonged, discharge - in a single, perfect pattern no less (electricity doesn't quite work that way) - to *burn* through several hundred thousand tonnes (at *least* ) of *rock* to make that formation visible from *space.* I added the emphasis because you're a moron.
But then how is Jupiter and Saturn generating their magnetism without the molten iron core....we know them to be giant gas planets
... so many audience reaction shots. Was this a comedy special?
The talk should have been 5 mins long. The title is about the magnetic field of planets. Get to the point.
The remaining 9 minutes are basically just sloppy saliva noises..
I don't know how from how long they come up with this But in 2012 when I was one of the Applicants for Mars-One mission I did have chance to hear for the Mars theraforming. Than I saw it in my mind. The planets who are located in the green habitate zone are potencial living organiums. Why? I will give you an example. why Mars Lost it's Magnetic field the well obviusly because the core get cold. No magnetic Field no protection fo the atmospheric air particles. Why Earth has it's magnetic Field and Mars lost it. Think about for a second... My theory is because Eatrh have the satelite called Moon. The Moon is creating magnetic friction with in and between the parcticles spetially in the Earth Core keeping it melted. What dose this say... It's says that the we dont need to theraforing Mars because withouw magnetic field it will be like to inflate ballon covered with holls. If we put in orbit around Mars a satelite in the right distance and with the right mass marse will activate on its own like a living Orrganisum waking up from long coma. And I am qunatum % shore it will happen.
If someone want to know more you know how to find me.
that's an interesting idea
The Universe is electrical in nature....
and there is no such thing as "magnetic friction" .... and no magnetic fields in "space" without electricity....
Petar is right to a certain extent. Though the friction occurring between earth and the moon is not magnetic but gravitational of nature. Gravitational or "tidal" friction is what's keeping the ocean's of Europa warm.
I think it is a better idea to create an artificial magnetic field between the sun and Mars, because shooting a large celestial object at Mars to generate the electic field is like using a nuclear bomb to grill your steak.
That has long been an idea floated by the scientific community. The material to do so could easily be found from the asteroid belt. However, the issue is timing. Even if humans are able to form an object large enough to cause the gravitational friction necessary and "launch" it into a sustainable orbit around Mars that causes that friction to occur, it will still take hundreds of thousands - if not millions - of years for the friction to create the desired effect on Mars's core.
Learn more about science before writing outlandish commentary.
I suspect that magnetic fields and the sun, moon influence will become part of this. I regard it as systems, not part specific. Cheers. jmho
We also need WiFi to survive
Sometimes I think being a sentient and curious being is more of a curse than a blessing. Don't you wish that you had no concept of death, for example?
David Brain, You did not address magnetic micropulsation and cellular replication. I remember reading that cells are sensitive to puslations of about 10 cycles per second. (from The Body Electric: Electromagnetism and the foundation of life. His follow up book Crosscurrents was also quite good imo.)
its going to be like investigating all the grains of sand on all the beaches... which first and to what ends? No exploration and discovery is done without eventual commercial ends... at least so far. looking at a planet 5k light years away may be a novelty it does not contribute to the greater good. no matter how much you discover about it
Did you know the people who invented lasers had no idea What their invention could be useful for, and at this point lasers have revolutionized multiple scientific fields?
AW Crowe
It does do the greater good to study science (and all the stars, etc). Eventually people will colonize each and everyone of them star systems and they'll live better than most of us. Science makes a country (or a great space faring civilization) great!
If we can get to space cheaper, then we'll develop unlimited clean energy, too. Then we'll make bigger telescopes. But in the meantime, we have to make do with spectroscopy... Necessity drives innovation which is supposed to erase poverty.
Imagine Benjamin saying to himself "na, quit wasting time playing around with kites in the rain"... He wasn't that cheap!
wow responses sound like starwars fans lol...... they think this culture and era created lasers 😂🤣😂🤣😂🤣
we will not be able to.... the tech advancement is capped off by our planet itself...... we don't have what we need to come up with real solutions. All our scientists would be dedicated to the space race if the were the case. thank God there are intelligent men and women that are still more focused on Earth ya know one of the most perfect blends of events that give us life as we know it....... people are too blind to understand the very possibility that we could be one of a kind period. Even out of trillions of stars and zillions of planets we could be there only one that produced intelligent life. very very very possible.
Definitely closet Vulcan lol most definitely
Mars have a weird magnetic field.. I wonder was it different million years ago..!
because the atmosphere exists due to presence of effective magnetosphere..
1st of all our planet does have an even distribution of inner anatomy including core, mantle & crust.. so it all are responsible to make produce a stable magnetosphere..
see to be very frank, our Erath is a kind of massive dynamo & it helps to generate eddy current what literally helps to protect earth from incessant violent solar activities..
I am afraid of having an unusual inner structure of Mars..
core materials & their uniform distribution make any planet stable geomagnetically..
you can google the visual of the poles of Mars.. you gonna shock that they might even be so close to each other..
one more thing, having a stronger field will be responsible for stronger small g, yeah, gravitational acceleration.. it results greater mg (weight)
in this perspective Jupiter has uniform but a way more powerful magnetosphere what is one of the reason of being this gas giant is inhabitable.. ✅✔️
The universe ain't 20 billions years old lol 14 billion 😄
who says water is the key? maybe methane works for another form of life. just look at life at this planet, and how life is in places where humans would die
Meanwhile I was almost abducted by aliens lol
We haven't found extraterrestrial life, but it has found Us alright !
That's it WOW a child can do the same presentation
You are talking about our kind of life.. Humanity is not very intelligent. There may be many types of "life" in the universe that we don't understand and therefore do not identify with.
So Mars is in a coma...and can be resuscitate by a gravitational tidal force from another celestial object...hmmm
after the 5th dad joke I tuned out
I dont believe they do but this is a prison planet and they do require magnetic fields.
OK, cool, nice, but this still doesn't change a damn thing about uniqueness of this planet and it's superior features... sorry but the rest of solar empire are remnants of the failed past and Earth is the only spaceship we have. Now I am against trying to make other planets as Earth, but let's first think about what really we can do to reverse engineering of the evolution. We learnt from the past already that our intervention with forces we can't control are usually affecting not just everything around us, but mainly and quite significantly ourselves. Also let's not forget that our changes we did on this planet and that level of civilization terraforming is not to last forever. Once in the future all the dams, power plants will stop functioning. our cities will be harvested by something much stronger than we can ever control. Lets base our thinking from here, are we really seed planter in this solar system? Honestly it would be magnificent role if we would achieve at least on Mars, but are we really life spreaders if don't know how to care about life on this planet? Are we really valuing life on this planet on that level that we can push it further in the space, or it is just our self importance or arrogance of feeling superior for this short while when we have enough resources to occupy our minds with this kind of thinking? I personally think we didn't understand the true value of life yet, because our chart of values keeps life somewhere behind something which we value much more than that.
I often think of it like planting a tree. If you plant a tree with your child and they grow up with it (them) and love them then they will realize how long it takes for a tree to grow and develop, making them much more reverent towards trees. Same thing on a much bigger scale here. We will be able to get a much better perspective of what we have if we could understand what it takes to make life on earth possible.
I also think that is you or anyone were to look at your life and understand fully the impacts you have on earth, you would make a whole lot of changes.
Traditionally war has helped us to learn and grow. I think that going to space and colonizing other planets is a much more effective and peaceful way for we humans to improve ourselves. By reaching for the stars
Depends what you mean by doesn't change a damn thing - it doesn't give us a concrete answer, but it seems to change what you might reasonably predict - he's saying we've found thousands of habitable type planets in one tiny bit of the sky, which extrapolated out equals forty to fifty billion habitable planets in the galaxy. Now if you said life forming on a habitable planet was EXTREMELY unlikely - say a billion-to-one against, (MUCH less likely than winning the lotto!) you'd still have to conclude there should be forty to fifty planets in the galaxy with life on them.
We still don't know, so sure it doesn't change a thing, but when you're talking tens of billions of opportunities per Galaxy, and hundreds of billions of galaxies in the universe, iterated over billions of years, that unlikely-sounding billion-to-one event must surely be happening all the time?! It's a tantalising glimpse of what the answer to the 'are we alone' question might be, and the ability to gather this data is another little step on our journey to finding out for sure!
I don't want to down vote a decent enough talk about my favourite subject, but just ignore the question of the talk completely why don't you.
there is other life in our galaxy and other intelligent life as well, 100 percent sure. the numbers prove it, 40 to 100 billion habitable planets.
Habitable doesn't necessarily mean Earth-like.
The numbers "prove" whatever you want them to.... That's how we ended up with blackholes, dark matter/energy and other non-existent flights of fancy....
I'm "100% sure" of this.
Habitable does not mean inhabited. Life does not spontaneously arise from non-living processes. If you roll a pair of dice a trillion trillion times you're never going to roll a thirteen - 100 percent sure.
Life came from a non living process. It's already happened. Your existence is proof. The universe wasn't created with life. If you give it trillions of more opportunities, it will certainly happen again. It is almost certain that there is other life in the Milky Way. There is probably life in other parts of our solar system. We are only years or decades away from proof.
I have a better question: have you heard if our lord and savior: audio normalization?
Seeker Rild and I’ve heard of unicorns, Zeus, Thor, the tooth fairy, Santa Claus and leprechauns.
Nothing works the way exactly you're saying your teachings have you all backwards David
Just get to the topic without invoking a "church" as the enemy.
His jokes were so annoying,i couldn't focus on the presentation!
Well the jokes kinda helped to understand and after all keep it entertaining for "not-so-interested-people".
I was interested in this and if I just listen to the facts, the jokes are automatically ignored, at least thats how it was for me.
If you couldn't focus on the presentation, you need to focus more I guess because his "off-topic" jokes were not distracting at all. If you listen to one physics class or some other mathematic-based stuff you would be greatful if it contains some humour, because these can be exhausting af.
omg, i thought i was the only one!
go do an open-mic if you want to horse around that badly.
the guy moves more on stage than robin williams
Dave Chappelle should redo this Ted talk
Id rather have cheesey jokes that keep people's attention rather than lose people's attention.. Thats the point of TED talks..
TED is a propaganda Stalin Machine -
blablabla
Earth is special in universe and only Earth has life because its created by divine will.
The (real) scientific evidence supports your model!
Science has not yet excluded the possibility that Earth is the only planet which harbors life. It's statistically certain that there is life somewhere else or has been in the past, since the universe is so ridiculously big.
Probably the very large majority of life is just a very primitive form of micro organism.
Look up Pasteur's flask experiment disproving the Spontaneous Generation of life. If I carefully created a million billion trillion replications of that experiment there would still be NO Spontaneous Generation of life. Having a huge number of galaxies doesn't change Pasteur's Results. Until Scientifically PROVEN otherwise, the Spontaneous Generation of life has been shown to NOT occur. THIS is a PROVEN Scientific FACT.
Now conduct your experiment, then allow the chemistry to play out over a billion years incorporating energy input from the Sun, electrical discharges, geothermal heat, and interaction with other primordial elements. Perhaps some new form of complex, self-replicating molecules might emerge. A human time scale experiment can not replicate conditions over a geologic time scale.
Why would God create a universe with trillions of stars and even more planets just to only populate one of those planets? The human ego is an amazing thing.
Anti-Christian BS
Jesus wouldn't like this talk?