New Discovery Could Reduce the Number of Potentially Habitable Planets (cnn.com) 104
Longtime Slashdot reader Tablizer shares a report from CNN: The hunt for planets that could harbor life may have just narrowed dramatically. Scientists had long hoped and theorized that the most common type of star in our universe -- called an M dwarf -- could host nearby planets with atmospheres, potentially rich with carbon and perfect for the creation of life. But in a new study of a world orbiting an M dwarf 66 light-years from Earth, researchers found no indication such a planet could hold onto an atmosphere at all. Without a carbon-rich atmosphere, it's unlikely a planet would be hospitable to living things. Carbon molecules are, after all, considered the building blocks of life. And the findings don't bode well for other types of planets orbiting M dwarfs, said study coauthor Michelle Hill, a planetary scientist and a doctoral candidate at the University of California, Riverside.
"The pressure from the star's radiation is immense, enough to blow a planet's atmosphere away," Hill said in a post on the university's website. M dwarf stars are known to be volatile, sputtering out solar flares and raining radiation on nearby celestial bodies. But for years, the hope had been that fairly large planets orbiting near M dwarfs could be in a Goldilocks environment, close enough to their small star to keep warm and large enough to cling onto its atmosphere. The nearby M dwarf, however, could be too intense to keep the atmosphere intact, according to the new study, which was published in The Astrophysical Journal Letters.
A similar phenomenon happens in our solar system: Earth's atmosphere also deteriorates because of outbursts from its nearby star, the sun. The difference is that Earth has enough volcanic activity and other gas-emitting activity to replace the atmospheric loss and make it barely detectable, according to the research. However, the M dwarf planet examined in the study, GJ 1252b, "could have 700 times more carbon than Earth has, and it still wouldn't have an atmosphere. It would build up initially, but then taper off and erode away," said study coauthor and UC Riverside astrophysicist Stephen Kane, in a news release.
"The pressure from the star's radiation is immense, enough to blow a planet's atmosphere away," Hill said in a post on the university's website. M dwarf stars are known to be volatile, sputtering out solar flares and raining radiation on nearby celestial bodies. But for years, the hope had been that fairly large planets orbiting near M dwarfs could be in a Goldilocks environment, close enough to their small star to keep warm and large enough to cling onto its atmosphere. The nearby M dwarf, however, could be too intense to keep the atmosphere intact, according to the new study, which was published in The Astrophysical Journal Letters.
A similar phenomenon happens in our solar system: Earth's atmosphere also deteriorates because of outbursts from its nearby star, the sun. The difference is that Earth has enough volcanic activity and other gas-emitting activity to replace the atmospheric loss and make it barely detectable, according to the research. However, the M dwarf planet examined in the study, GJ 1252b, "could have 700 times more carbon than Earth has, and it still wouldn't have an atmosphere. It would build up initially, but then taper off and erode away," said study coauthor and UC Riverside astrophysicist Stephen Kane, in a news release.
What is life? (Score:2)
Yes, on earth, carbon molecules are, after all, considered the building blocks of life. Just because that's what we know. And even on earth, deep down the earth's crust or oceans, there are living organisms that defy that definition.
So yes, for carbon-based life, it may be a dire discovery. But I'm fairly sure there are other forms of life out there.
Re:What is life? (Score:5, Interesting)
I think the basic chemistry is the reason why most scientists assume all life forms will be carbon-based. Other elements don't form long complex molecules nearly as readily, which would be a prerequisite for the molecule to be able to store the large amounts of information necessary to form life.
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Other elements don't form long complex molecules nearly as readily, which would be a prerequisite for the molecule to be able to store the large amounts of information necessary to form life.
It could be, you mean. But it could also just mean it takes a lot longer... which would only be relevant if our planet were particularly old. Or, it could only mean it would take a lot longer here, but in some other conditions it could happen just as quickly. Earth seems to have been an ideal place for carbon-based life to evolve and flourish, but maybe some other place is an ideal place for the development of some other kind of life.
For example, under some conditions crystals of various kinds form quite ra
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Re:What is life? (Score:4, Insightful)
There's more to it than that though - all sorts of natural processes break down complex molecules, and new ones have to form faster than old ones break down in order to get a high enough concentration for more complex systems to begin to form and replicate using those molecules.
Also, silicon is really the only other element capable of forming the wide range of complex molecules that carbon can, and its larger size translates to weaker and more rigid chemical bonds. Also, it's a lot less common in the universe than carbon (which is part of the normal stellar fusion cycle), and seems much more prone to getting locked up into stable minerals like quartz.
Finally - at ~4.5 billion years, our planet (and sun) really is pretty old in the grand scheme of things. About 1/3 the age of the universe, and 1/2 the age of the oldest third-generation stars that would be likely to have enough heavier elements in the proto-stellar cloud to form planets with an Earthlike mix of elements. That's a huge gap given how fast carbon life emerged and evolved here - hence the Fermi paradox - but dwindles pretty fast in the face of significantly less volatile chemistry.
All of which is to say - there's no reason to believe that non-carbon life is impossible, but the deck is stacked even harder against it than for carbon-based life.
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You're missing the point. Crystals have nothing--I repeat, nothing--to do with it. What's unique about carbon is its ability to form a huge--limitless, really--variety of chemical. The reason carbon is the basis of life is chemistry, not time.
Re:What is life? (Score:4, Informative)
And even on earth, deep down the earth's crust or oceans, there are living organisms that defy that definition.
No. There is life deep underground, but it is still carbon-based, has DNA, and uses basically the same genetic code as all other life on Earth.
Lithotroph [wikipedia.org]
But I'm fairly sure there are other forms of life out there.
Not likely. Carbon supports far more complexity than any other element, and it is extremely common in the Universe. No other element has anything like nucleic acid polymers, proteins, and enzymes.
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You're just a carbonist and a noncarbonphobist!
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The thing about infinity is no matter how you subdivide it and decimate it, it's still infinite.
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Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space.
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Carbon supports far more complexity than any other element,
Silicon can also have 4 bonds.
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I was going to say the same - silicon can form analogs to pretty much any carbon-based chemical.
However. Silicon's larger size means those chemical bonds will be both weaker and more rigid, making them both less stable and less mechanically versatile than their carbon equivalents (a protein is basically a little molecular robot), so I'd say the deck is stacked against it compared to carbon life. Certainly not impossible, but probably a lot less common
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No, they're a great example of a fictional concept of silicon based life based on plot convenience rather than science. There's a difference.
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What about life on earth that doesn't have "genetic codes", no RNA or DNA? Complex molecules that form and reproduce their complexity? Like phospho-lipids.
RNA (Score:2)
What about life on earth that doesn't have "genetic codes", no RNA or DNA?
To have life, you would need:
- something that stores information and can be replicated into more copies of itself.
- can react and/or modify stuff, i.e: chemically react with the environment.
If you don't go into complex living being that have split these into separate component (we use DNA for information storage and easy replication, we use proteins for most of our enzymatic reactions. Though we still use RNA here and there), RNA is about the only one known to current chemistry that can have both functions
Re:What is life? (Score:5, Informative)
Silicon has similar chemical properties as Carbon, and you could imagine life based on Silicon molecules rather than Carbon molecules. But there is a problem. Silicon reacts very slowly, and Silicon based molecules are chemically very stable. That's why we use Silicon as a sealing material. Life based on Silicon would evolve not in billions, but trillions of years. Before the first colloids figure out how to duplicate themselves, the star in their Solar system has gone Supernova.
If there is Life somewhere else, it is highly probable that it is Carbon based, which means, that the surface of the planet should not be hotter than about 300-400 K, because above that temperature, nearly all Carbon based molecules are destroyed. On the other hand, you need a solvent to transport materials, and water is the most potent solvent we know. And because both Hydrogen and Oxygen are present nearly everywhere, it is also the most available. To get liquid water, you need temperatures above 250 K, which makes the temperature window for a life bearing planet's surface very small.
Not Good Arguments (Score:5, Interesting)
For life not based on Hydrogen, Carbon, Nitrogen and Oxygen, you need additional conditions to remove the Carbon
No you do not, as you actually point out later, you just need conditions where carbon-based life cannot evolve such as lack of water, extreme heat or cold etc.
Life based on Silicon would evolve not in billions, but trillions of years.
There is no scientific basis for this claim since you are assuming that the evolution of life on Earth is "standard" and we have no idea whether it happened really quickly or really slowly or was indeed average (or even unique). That's the problem with a sample size of one. Next, you are assuming Earth-like conditions which is not necessary since, as you point out silicon compounds are more thermally stable so, if silicon life were possible it might evolve in a higher-temperature environment where reactions would happen more rapidly.
I'm not saying that silicon-based life is possible but the arguments you gave are not reasons to rule it out. As I understood it the bigger issue used to be the stability of long, complex silicon-based molecules but I've no idea if that's still the case or whether there would be conditions under which they would be stable.
This is the danger (Score:3)
As long as you are extrapolating from a single data point, you have to make assumptions which you have no way of knowing whether they're even remotely close to being correct.
Re:This is the danger (Score:4, Interesting)
If you think I'm being unfair, this is akin to a medical doctor still not knowing what water is in relation to the human body.
They only just discovered in 2015 that the lymphatic system permeates the brain...
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Exactly. We do not even know how life came to be on our planet. One option is still "from somewhere else" and then things are wide open.
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> One option is still "from somewhere else" and then things are wide open.
Not really. If it came from somewhere else, then that means it had considerably more time to evolve than the scant few (hundred? We're not sure yet) million years it had if it started here.
Best case scenario is still started as fast as it seems to have done here, but it also opens the window to it having taken far longer. Possibly even billions of years if it originated on another star. Which means it's much less likely to have a
No- (Score:5, Informative)
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Yep. Not even close to being a "new discovery." The topic has already appeared at least twice on SD:
"Proxima Centauri Shoots Out Humongous Flare, with Big Implications for Alien Life"
"New Paper Explores The Prospects For Life Around M-Class Stars"
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I find it even funnier that the headline is phrased as if the act of discovery has made these exoplanets uninhabitable.
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Agreed. I remember having this conversation before the internet was invented, when I bought Traveller's Book 6:Scouts, that had their advanced and utterly awesome detailed system generation rules that allowed habitable planets in orbit 0 on M0V primaries.
Yes, ok I had to look that up.
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Yup. We've taken the concept of panic mongering headlines to the point where even space news now has to have a panic headline. So very stupid.
What estimate did Fermi use? (Score:4, Interesting)
I'm generally interested in the Fermi Paradox in all of its forms, so the question for this story is what value did Fermi use for that parameter when he was scribbling on the back of his envelope (or whatever he scribbled on). Pretty sure the current estimates are way higher than Drake used...
My new thought on resolving the paradox involves time. We evolved in geologic time. When we started becoming intelligent the rate of change was greatly accelerated. Call it historic time. But the natural progress is for us to create our successors, which to me means AI, but... The rate of change has increased again, though I'm not sure what to call it. The AIs must change really fast, so no wonder they have nothing to say to us. I used to speculate they might be curious, but now I doubt even that. If they are watching us at all, then it would just to make sure we don't release a paperclip maximizer. https://en.wikipedia.org/wiki/... [wikipedia.org]
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Frank Drake first wrote his formula in 1961.
Some of his numbers seem optimistic in hindsight. He estimated that 20% to 50% of stars have planets, which may be about right. But he estimated that nearly all habitable planets would evolve life and that life would almost always become intelligent.
He estimated that 20% of civilizations would emit detectable radiation, which is also very optimistic. Humans have been using radios for only a bit over a century, and we are already transitioning to fiber and encrypte
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The general public and mass media love the Drake Equation, even though they fundamentally don't understand it.
They look into the sky, see all the stars, and say "where is everyone -- we must be special". The equation doesn't cover that. To best understand it, Drake needs to be paired with that eminent scientist, Dr. Emmet Brown who famously quipped "You're not thinking four dimensionally."
N = the number of civilizations in the Milky Way galaxy with which communication might be possible (i.e. which are on th
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Because of the risk I mentioned of the amok paperclip maximizer, I actually think it likely that the aliens might post observation satellites near life-bearing planets. One of the things they would be looking for would be the kind of electromagnetic radiation we started emitting in the last century. And if so, then our satellite has already phoned home...
"But are they curious aliens? Just listen." (With apologies to Rocky the Flying Squirrel.)
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I call this one the Cthulhu theory, because in Lovecraftian Mythos the Migo occupy the most distant object in our system as a point of observation. :-)
The problem is, for me anyway, if we play by the rules we know and don't invoke "magic", that satellite phones home at the speed of light. Those long distance transit times are also limited by the light cone and a complete buzz kill.
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As I see it, the electromagnetic trigger would be quite late in the game. Earlier triggers would have already warned them to post a reaction force nearby.
And if they weren't curious, then they would have already exterminated us. Therefore I conclude they must be curious, but I am accusing them of also being cautious.
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Why would they be hostile? If they have workable interstellar travel, they're so far advanced from us we'd barely register as a technological curiosity.
We are more advanced than 1950s Soviet Union (Score:2)
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If they are concerned with big time, as in geologic time, then no paperclip maximizer can be permitted to exist. Any rate of compound growth sustained geologic time is too much growth.
Not hostility. Simple self-defense.
And we would have no defense if they were serious. However, they might be willing to keep a few specimen humans around for some kind of menagerie.
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Time is essential to the Fermi Paradox.
Since the first accretion of matter that eventually led to the creation of this solar system we have been gravitationally advertising our presence to the universe and attracting all manner of masseous objects for billions of years. We are essentially spinning rapidly around the hole on a cosmic putting green, and anything within our light cone is putting past us to that hole. Impacts are certain.
This is why there are no civilizations to observe. Extinction events cau
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Interesting approach, but I mostly disagree. I don't see any natural lifespan for AI entities.
However I have a working label for my third category of time. Humans were created in geologic time, society in historical time, and AIs are dealing with quantum time.
Re: What estimate did Fermi use? (Score:2)
I think i see what you are saying about quantum time. Evolutionary iterations happen much faster in silicon than with DNA. Its a whole different time scale. Eons in instants, put poetically.
What i am pointing to as the issue for both biological intelligences and AI as well is the fragility of the Earth.
Continuance is questionable on a planet that has been proven to experience periodic events that could wipe out humans and computers alike.
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That also clarifies some parts of your earlier comment. I think we are basically in concurrence, though I am basically sure that there are some long-lived intelligent entities--and it's my view that they are almost surely AIs, not biological products.
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That depends a lot on how common life is. Because while we've only been broadcasting the presence of intelligent life for 150ish years, we've been broadcasting the presence of some kind of life MUCH louder for a couple billion years, ever since the great oxygenation event when photosynthesizing organisms pumped ridiculously improbable amounts of oxygen into the atmosphere.
Unless I suppose the aliens evolved in an oxygen-free world, in which case we might look like some kind of unexplained oxidizing hellwor
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There are also an incredible number of confounding variables to the Drake Equation / Fermi Paradox that serious scientists just ignore.
The preamble of the Drake equation should say "The following is based on a series of negative assumptions, such as no contact between civilizations under any circumstances, no uplift of pre-sapients, and no way to transmit information faster than the speed of light."
Another way to think about this is the idea that there is nothing like a Galactic version of the Roman Empire.
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That's why I think the accelerating time factor is becoming so important. We can't keep up anymore, though our AI descendants might have a shot.
I still need a mental label for the new kind of time... How about geologic time to historic time to quantum time?
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Indeed. At least as a group, this installment of the human race is unlikely to be capable of long-term survival. Too many assholes, too many easily manipulated idiots.
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If some other society progressed to the point where the AIs, the robots, or whatever other "non organic" life took over, they likely view us the way we view ants playing on the sidewalk. A curiosity of some ancient life form that's fun to watch for a moment, maybe fun to swat if we're feeling saucy, but rarely worth spending more than a few seconds contemplating here or there as we go about our regular business.
Folks panicking over the coming singularity don't get how insignificant we'll be to whatever is c
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Mostly concurrence, but one of my premises is that the AIs will tend to converge and therefore find it of limited interest to study each other. On that basis, they might be interested in organic intelligence to see the various paths that lead to the convergence. Good and less good ways to get there.
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>> But the natural progress is for us to create our successors, which to me means AI
AI is a rabbit hole, like Alchemy, Heraldry, or Astrology
A few weak surface phenomena without nearly the depth or richness to be meaningful.
Technicians have yet to make virtual reality or nuclear fusion practical and both these problems are far more tractable than an AI even as intelligent as a goldfish.
In geologic time we will die. If we spread out to the stars we will do that as humans, not as disembodied consciousn
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I'd buy into your unclear theory more if you managed to clearly define what "human" means. Unfortunately, so far whatever attribute or behavior we manage to define as "human", we are then able to build a computer that does the same thing faster and better. Time has become the kernel of my philosophic system, and the computers are SOOOO much faster than we are.
What have you read on the topic? Might be a point to this exchange, but not based on your current brief comment. (Just started Rationality by Steven
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I don't care if you buy into my theory. Your comment shows that you didn't understand my point. Read up on quantum mechanics experiments for a few years and you'll probably get it. Odds are, as a slashdot poster who felt compelled to shoot off his mouth and remove all doubt, you're either high functioning aspergers or an intellectual lightweight. Feel free to continue just as you were.
What to say about poor writing? (Score:2)
NAK
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The big problem is the range of the estimate
https://en.wikipedia.org/wiki/... [wikipedia.org]
9.1 × 10^13 to 15,600,000 civilsations in the galaxy
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So why do we not see any evidence of the AIs in the universe?
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The big problem is the range of the estimate
https://en.wikipedia.org/wiki/... [wikipedia.org]
9.1 × 10^13 to 15,600,000 civilsations in the galaxy
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So why do we not see any evidence of the AIs in the universe?
For the same reason we don't spend a lot of time talking to ants, impressive though their "civilization" might appear to be.
Rare Earth (Score:4, Interesting)
I've always been a pretty big believer in the rare earth hypothesis. Simply being in the "habitable zone" of a star is not enough. Venus is technically in the habitable zone of a habitable star, and it is not actually habitable (though it's possible it was at one time).
I think the more we learn about the conditions for life, the more we realize how extremely specific they are. You need the right kind of star, a rocky planet, the right kind of orbit (not just the right distance, but not too elliptical and the right influence of other celestial bodies) , the right atmosphere, the right amount of geothermal/volcanic activity, liquid water (probably), and likely a whole host of factors we haven't even discovered.
The rare earth hypothesis resolves the Fermi paradox pretty readily. If the earth is one in a billion, the closest intelligent life could be millions of light years away. If so, it wouldn't be terribly surprising that we haven't seen or heard from them. The distances are just too vast. Timescales would be impossible for establishing communication.
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If the Earth is one in a billion, the closest intelligent life could be millions of light years away.
Pedantic nitpick: There are a billion stars within 5,000 light-years of Earth.
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You might as well be bragging about how easy it is to grow a double-headed foot-long dick.
Genetically engineered, or do you mean the on-demand appendage on a malleable synthetic life form that replaces the current bio sapiens?
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And you need a relatively large moon to stabilize the planet's rotation so that it doesn't swing about wildly.
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And you need a relatively large moon to stabilize the planet's rotation so that it doesn't swing about wildly.
And a valid heat source.
Hate to nitpick here while we dream of inhabiting other planets, but that whole warm-blooded thing is kinda important.
Re: Rare Earth (Score:2)
IIRC venus was just inside the habitable zone when the sun was new but as the sun has aged it's got hotter so the planet is now just outside. Though it had its runaway greenhouse long before that happened which perhaps suggest the theorised habitable zone is optimistically wide.
Re: Rare Earth (Score:1)
Re:Rare Earth (Score:5, Interesting)
The rare earth hypothesis resolves the Fermi paradox pretty readily.
So does the idea that species just tend to wipe themselves out before they become spacefaring. About the same time you get powerful enough to do that, you also become powerful enough to fuck up your biosphere. At least, so says our sample...
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As an explanation for the Fermi Paradox this suffers from the problem that it has to apply to every proto-space faring species without exception to account for the complete absence of space faring civilizations colonizing the Milky Way. It it the necessity of universality that creates the paradox.
Even the evidence of hand of humans suggests that actually avoiding self-extinction is readily doable, even if in the end we don't.
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Even the evidence of hand of humans suggests that actually avoiding self-extinction is readily doable, even if in the end we don't.
Oh shit, if I knew we were going to debate self-determination, I would have worn a tie.
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Corollary: when you become advanced enough to consider substantial interstellar travel, you no longer need to do it. The same level of technology would allow you to live permanently and sustainably in space, without the additional energy expenditure (and risks) of moving your ships/habitats to other solar systems. You can do all the exploration easier/faster/cheaper with unmanned interstellar probes and mega-scale space telescopes.
The more I think about it, the less likely things like interstellar colonizat
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In addition to the "rare Earth hypothesis" one should add "rare language using tool-making intelligence", which is even more strongly supported by the evidence on hand.
Despite the popularity here of asserting that the Earth as a whole is but "one data point", as if it we were just taking its weight or something, we have a vast amount of data about the likelihood of tool-making intelligence like our own evolving. Half a billion years of animal life, millions of animal species, and there is no evidence of any
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Tool making is very different from tool usage. Several animal species use "tools" in the form of sticks or rocks they find (and some may go so far as to break a stick in half or otherwise make minor modifications), but only humans and hominids make true tools that take planning and thought to create.
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Okay, I'll bite - what evidence do you have that Venus is "not actually habitable, though it's possible it was at one time"?
Should I be assuming your definition of "habitable" is "I could live there without a spacesuit"?
If so, I take it you can prove that life cannot evolve without a reasonable facsimile of a twin of Earth (Terra, Tellus, whichever name you prefer)?
Ya, but ... (Score:2)
Not sure this is a typical planet on which to expect life. It's *really* close to the star; another article I read compared it to Mercury. From TFA:
GJ 1252b orbits less than a million miles from its home star, called GJ_1252. The planet reaches sweltering daytime temperatures of up to 2,242 degrees Fahrenheit (1,228 degrees Celsius), the study found.
thats terrible (Score:2)
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Panspermia (Score:2)
As we can see on Earth, life is ubiquitous wherever the conditions suit and this "discovery" does not impact on hundreds of billions of other worlds (just in the Milky Way) that we know to exist with a near certainty.
As far as we can tell, life only started once. This infers that life came from some place other than Earth since if life had a single genesis, it is highly unlikely that we would just happen to be living on the rock on which it started.
Panspermia. Literally, the seeds are everywhere. And like
Re:Panspermia (Score:5, Interesting)
There's no reason to think that life only started once on Earth, let alone leap to the absurd idea that it only started once in the whole universe. All we know is that a particular instance of it won here. Once life became firmly rooted, we have plenty of good reasons to think any further abiogenesis was doomed to be unable to compete and soon became impossible anyway due to the way life drastically changed the planet.
And we have strong evidence against panspermia, because we can trace back evolution enough to tell that the first life on Earth was extremely simple. If it'd come from elsewhere, it would've been starting with billions of years head start on its evolution. We might've started with modern-style bacteria, or even tartigrades or something, but we know that we did not.
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As far as we can tell, life only started once.
As far as we can tell, we know almost nothing about what conditions are like on other planets.
This infers that life came from some place other than Earth
The author implies, the reader infers.
We have yet to find DNA anywhere else but Earth, so we can't make a reasonable guess about where life began that's more educated than "here".
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We have yet to find DNA anywhere else but Earth, so we can't make a reasonable guess about where life began that's more educated than "here".
I guarantee you that Wilt Chamberlain's DNS is all over the solar system...
Re:Panspermia (Score:5, Insightful)
As far as we can tell, life only started once.
The first indications we have of life suggest it appeared immediately after the end of the Late Heavy Bombardment, during which Earth was repeatedly sterilized by impact that raised the entire outer crust to temperatures above what organic life can sustain.
This suggests the possibility of life appearing over and over, only to be extinguished, until the extinguishing stopped. The very early appearance after the end suggests that given the right conditions the appearance of life is highly probably, and even a fast phenomenon on the cosmic scale, which is the opposite of the suggestion you are making.
The claim of only one appearance even after the LHB is a very weak one given that we would expect only one life-lineage to survive competition over this enormous time scale. Even the earliest forms of life of the lineage that did survive are lost now -- whatever it was that preceded the complex DNA-based system that became the basis of every free-living organism.
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"As far as we can tell, life only started once. This infers that life came from some place other than Earth since if life had a single genesis, it is highly unlikely that we would just happen to be living on the rock on which it started."
That is so far from proper statistics you can get. You know life exist on earth, so that probability is one, you don't know that life didn't start on earth, a completely unknown probability, you can't just assume that probability is close to zero.
It is much more likely that
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Take the likelihood of life to begin on a suitable planet (probability P1), and the likelihood of life being transported between planets (P2)... P1 is always greater than P1*P2 and our working assumption should be that Earth life began on Earth.
The Actual Discovery. (Score:2)
(Junior)"We did it! We found an absolute clone of Earth, and it's only ONE light year away! This is amazing!"
(Senior) "Uh, the speedometer on our rocket goes to 30,000MPH. Before you pop your third bottle of champagne, you should probably do the math."
Wake me when the warp drive comes out of beta testing. Until then, hearing about another "habitable" planet is about as rewarding as reading my horoscope.
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You think it's uninteresting that life would exist nearby because you can't physically get to it? That's... sad.
No, I don't think it's uninteresting. Just as I don't find comic books uninteresting. What I find sad watching "professionals" and their clickbait team get humanity pumped up over a fantasy. We don't pay scientists to write science fiction.
And if I'm being a pessimist here, then I challenge you to define the realist with this. We're not even close to being able to travel at light speed. Even if we do somehow figure out the mechanics, we've got a whole new set of medical challenges putting meatsacks in
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Don't need lightspeed, and at least probes to nearest stars are certainly just an engineering and funding problem, no barriers forbidding them at all.
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Don't need lightspeed, and at least probes to nearest stars are certainly just an engineering and funding problem, no barriers forbidding them at all.
Voyager 1 launched in 1977, and has its first date with a star about 17 light years away. Practically around the block in terms of distance as compared to most discussions. It's estimated to take our probe about 40,000 years to get close to that one. We have but a handful of stars within five light years of Earth.
You're right. We don't need lightspeed. We meatsacks need some form of suspended state while we wait an impossible amount of time for the technology to come even close. Even traveling at just
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You're funny thinking we only know how to make chemical rockets. Guess again, fission alone can get us to 5 percent lightspeed, it's pure engineering problem.
My bet is on K dwarfs. (Score:2)
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What about Q?
Earths' magnetosphere? (Score:2)
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It does. The lack of a strong magnet field around the planet Mars is suspected to be one of the reasons the planet lots its atmosphere.
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Protect your atmosphere, duh! (Score:2)
Interesting: yes. Earth-shattering: No!
Maintaining an atmosphere for 100s of million years against the onslaught of stellar winds (plasma!) is no mean feat. A sufficiently strong, intrinsic (dynamo) magnetic field helps – here is looking at you, Earth! – but other means work too; just look at Venus and her ionosphere/induced magnetosphere.
In the end the name of the game is to prevent the stellar wind from stripping the atmosphere off the planet - and you need to know quite a bit about the planet
What about magnetic fields? (Score:1)
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