Other Solar Systems Could Be More Habitable Than Ours 143
A reader sends word of new research out of Ohio State University into the possibility of life arising in other star systems:
"Scattered around the Milky Way are stars that resemble our own sun—but a new study is finding that any planets orbiting those stars may very well be hotter and more dynamic than Earth. That's because the interiors of any terrestrial planets in these systems are likely warmer than Earth—up to 25 percent warmer, which would make them more geologically active and more likely to retain enough liquid water to support life, at least in its microbial form. ... 'If it turns out that these planets are warmer than we previously thought, then we can effectively increase the size of the habitable zone around these stars by pushing the habitable zone farther from the host star, and consider more of those planets hospitable to microbial life,' said Unterborn, who presented the results at the American Geophysical Union meeting in San Francisco this week."
More habitable? (Score:3)
For life in general, maybe. Possibly. But not us. Humans require a very delicate balance of things that while any one of them is quite common, there's not a lot of evidence that all of them together is. Oxygen/nitrogen atmosphere in the right concentrations, and a lot of H2O? Probably not hard to come by. Strong and uniform magnetic field to trap the atmosphere and deflect solar radiation? Hard to observe empirically; It could be very rare by some accounts. Presence of a moon or other astronomical event to keep the planet spinning on a single axis and not two? That's somewhat common, though limited evidence suggests the closer you get to a star, the less moons will be in orbit around each planet, so there is that. Stable rotation of the planet at a speed sufficient to prevent one side or another from burning up? Again -- evidence points to a moon being a good promoter of this, and not that uncommon. But we have no direct observation of how fast (most) of the planets detected so far in the habitable zone rotate.
And lastly, let's not forget: We're rendering our own planet increasing inhospitable to life by the year. It may be that, in the future, we look for the presence of global warming as an indicator of alien life, as we frantically work to either save our planet, or try to find a new one to destroy.
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Are we making earth less hospitable, or just less hospitable to the life that currently dominates? Sure the changes from global warming will cause humanity a great deal of trouble, but let's say humanity dies out but the increased temperatures stay in effect - wouldn't life just adapt to them eventually - it's just a few degrees.
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What will kill us isn't the rise in temperatures, it's most likely the wars over increasingly limited resources such as arable land, toss in a bunch of nukes and those acres won't be arable/hospitable for long.
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Will there be less arable land, or will it just be located further north?
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Eventually it'll be located further north but it takes time for muskeg to turn into good soil.
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while that is a big picture view, I'd think taking an attitude that while we are the top species, we'd at least consider the idea that pooping in our own house is not a good thing to do.
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I completely agree. But let's not confuse a warmer planet with one that is less hospitable to life. We are messing things for ourselves and many species currently alive. But we are also making it better for some of the other species.
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You speciist!
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Oxygen/nitrogen atmosphere in the right concentrations
You may be surprised to know that life itself created our modern atmosphere, there was virtually no free oxygen for several billion years but there was life pretty much as soon as the things cooled down enough to allow oceans to form. Life put the oxygen in the atmosphere, the concentrations we have today are not just "luck".
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You may be surprised to know that life itself created our modern atmosphere, there was virtually no free oxygen
Which naturally means no other planet could possibly have developed differently from ours, perhaps in a way where oxygen isn't somehow trapped during its creation, or is later freed by a planetary event separate from the creation of life... /snark
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Oxygen is highly reactive; it doesn't stay put in the atmosphere for very long at all before it bonds with something else and stops being elemental oxygen. In order to have free oxygen in our atmosphere, it needs to be constantly replenished- whether by life (as on Earth) or some other process.
Planets with an oxygen-rich atmosphere but no life just straight up can't happen.
Error, error (Score:5, Informative)
Sorry, lots of things wrong with that post.
It's physically impossible for an object to spin on two axes - if you try you just get it spinning around some intermediate axis. What a moon does is gravitationally "knead" it's parent planet, causing tides in the atmosphere, oceans, and rock. That causes the planet to heat slightly, and may promote the development of life in other ways (tide pools may have played an important role in the early development of life on Earth).
Also a moon will *slow down* its planet's rotation, not speed it up. That tidal heat dissipates energy until the planet is tide-locked with it's moon - in our case we'd have about 12 days per year. The same effect happens in the other direction as well, which is why only one side of the moon is visible from Earth. The sun has a similar effect, though weaker since the sun is much, much further away. Venus and Mercury likely have such long days because they're considerably closer to the sun and so the tidal forces are much greater - given enough time they'll be fully tide-locked and have permanently light and dark faces.
Finally, finding a new planet for us to move to in order to escape the consequences of our actions is not a realistic option - Mars is a likely a viable terraforming candidate, but it'd likely be far easier to repair the damage to our own planet than make that desolate planet green, not to mention it would likely take at least several, and we probably don't have that kind of time if we don't get our act together. Even if we managed the terraforming, transporting several billion people interplanetary distances would likely be beyond our capacity in a relevant timeframe - we're currently adding hundreds of thousands of new people every day. We might be able to create colonies which would be nice for the rich, powerful, and highly desirable, but the vast majority of the population will have to deal with the consequences.
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It's physically impossible for an object to spin on two axes
Really? So you're saying it's possible for something to have only x or y motion, but not both? So if I take a dot and paint it on a ball, I can spin it so the dot is appearing to move along a straight vertical line... but there's no way that it can be spun so that from the observer's perspective, it could appear to be moving diagonally? It is possible for something to spin on two axis, because all objects in space are three dimensional and there can be positive or negative motion on any of those axis' relat
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It's physically impossible for an object to spin on two axes - if you try you just get it spinning around some intermediate axis.
Having a large moon does act to reduce the precession and nutation of the axis, though. Mars will, over a few million years, change the angle of its axis enough that its extreme might be over 45 degrees; there will be similar changes to climate during the period. Having this much variability cannot be good for any life that arose during one part of the cycle, unless something else (like extensive oceans) buffers the changes to allow life to shift to where it is better. The distant large co-orbital planet
Figured it out (Score:2)
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December 21, 2012 the date of first contact! Seriously, what will we do when/if this happens? Will it mean a paradigm shift for humanity or the implosion?
Well, 1st contact will put our patent system in a serious disadvantage if they're more advanced than us. [insert conspiracy theory whereby Patents stifle contact with aliens in addition to innovation]
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December 21, 2012 the date of first contact! Seriously, what will we do when/if this happens? Will it mean a paradigm shift for humanity or the implosion?
It probably depends on how tasty the aliens find us.
Like the drake equation (Score:3)
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Out of the unfathomable amount of planets in the universe, there just has to be a better one somewhere. Trouble is getting there
The technology required to get us there means living self-sustained in space. Then we'd only want for chemical resources, which we could get by flying through any nebula much easier than by mining a planet. If we find a better planet what makes you think anyone who could get there would want to?
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because if you have a power, lifesupport, radiation containment, etc, failure on a space ship everyone on board would die. mean while on a earth like planet you have a power failure you can open a window for light and air, and nuclear fallout on a planet can be survived on a spaceship your shit out of luck
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A planet is basically just a very large space ship with no engines. At the extremes of scale planets face the same problems space ships do (look at the climate problem -- we're overtaxing our atmosphere reprocessors, putting out carbon faster than it can be scrubbed out of the air), and space ships can offer the same solutions planets do.
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it takes centuries for reach point of no recovery for climate change even then whats to stop adaptation/mutation form saving your species? on a spaceship your air filter system dies you die in hours
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Depends on the size of the spacecraft, the number of air filtering systems, power supplies, zones, etc. You're not really considering a properly engineered system there, just a naive design. As for climate change, think about what the impact of a good sized asteroid or comet would do. A spacecraft can simply dodge.
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Also, spacecraft can easily dodge big rocks and comets. Planets can't dodge those at all, and so far, we don't have any other solutions, either. Spacecraft can also hide behind other objects during solar storms. Planets, and those on them, just have to deal.
There's also a fair bit of science you can do better on a (or many) spacecraft; astronomy, for one.
Once manufacturing gets a proper foothold in space, assembly of (just about anything) will be a great deal easier as well. Gravity is really annoying when
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A planet is basically just a very large space ship with no engines.
And a human being's just a very complicated collection of cells.
Intelligent life (Score:3)
I can't help to think there is more intelligent life elsewhere. There has to be....
As we just are too stupid to find it yet.
I hope we live to see proof....just so the backwards amongst us eat crow.
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We're probably only going to find anyone who's trying to be found by backwater hicks (galactically speaking) using the methods we're using today.
Re:Intelligent life (Score:5, Funny)
I can't help to think there is more intelligent life elsewhere.
Me too. I keep waiting for news to come back from NASA's Voyager team about the probe making contact with an alien artifact just beyond the Heliosphere.
My take on the Fermi Paradox is that there's a huge meta-material cloaked universal translator projecting a message to any would be visitors:
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Warning: Human Infestation
This star system is Quarantined
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We apologize for the inconvenience.
-The Gods
Definition of 50% warmer (Score:2)
What is 50% warmer supposed to be? This makes no sense in physics. Only maybe if you refer to temperatures in kelvin.
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It's probably talking about geothermal energy released in proportion to the planet's size. If you're talking about two rocky planets of the relatively same size and mass, the one with the greater content of heavy radioactive elements like Thorium will have the hotter core. This expands the planetary habitable zone outward since the higher internal temperature can compensate for the reduced solar radiation, so you'd have a wider range of planets that are capable of sustaining liquid water. A hotter core will
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Solar System (Score:2)
The term "Solar System" is a proper noun, not a generic term. The term the article was looking for is "planetary system."
Large Moon (Score:2)
We may have 25% less radioactive elements in our planet's interior than some of these other planets, but we have a large moon that is causing a significant amount of tidal friction. That should help close the internal heat gap a bit...and as a bonus it keeps our axis fairly stable.
There are many different types of homes out there. Some just have better floor heating than Earth. I rather like our bright heat lamp in the sky...so do the plants in my yard.
A good discovery nonetheless. I'm excited that life
High Score! (Score:2)
This is one of those mind-bogglingly vaguely self-evident articles that you still can't help but try to correct (well, at least I can't.)
For what definition of habitable? For a given hypothetical type of plasma-based or magnetic life, I imagine the sun is a pretty happening place to hang out.
And yet, no matter what definition you use for habitable, what does "more" habitable mean? Surely it either is, or isn't. What are we measuring here?
And yet, no matter what definition you use or how you measure it, t
'Dynamic' doesn't sound so great (Score:2)
More likely? (Score:2)
The bolded part is impossible. The probability of the Earth retaining enough liquid water to support life -- and not just in its microbial form -- is 100% (its known that it does, so there is no probability that it does not.) So its no
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Oh? Say that again in another billion years, when the Sun heats up enough to evaporate all the liquid water on the Earth, probably turning it into another Venus.
Still doesn't work (Score:2)
The comparison wasn't to Earth of the future, but, if it was a comparison to Earth "when the Sun heats up enough to evaporate all the liquid water on Earth", then saying that planets in the systems studied would be "warmer than Earth [...] which would make them [...] more likely to retain enough liquid water to support life" would still be impossi
It's just like the Earth... (Score:2)
Reminds me of a saying:
The Moon is just like the Earth, only deader.
Wait, warmer is better (Score:2)
So warmer is better? (Score:2)
But that's not what Al Gore told me!
so now it's 25% warmer on other planets.... (Score:2)
moon stablized system (Score:2)
One-up (Score:2)
Why are we impressed with this?
A typical quasar looks about as bright from 33 light years away as the sun does from earth. A quasar's lifespan is from tens of millions to a few billion years.
That means in galaxies with a quasar, there is a shell 33 light years in radius, and a few light years in thickness, in which essentially every planet in every stellar system (as well as rogue planets and moons) is in the "habitable zone".
That seems way cooler to me than speculation about a few planets being in the habi
the Cyanobacteria is always blue-greener (Score:2)
The habitable zone is an invisible line. (Score:3)
First, we don't know enough about life to know that life based on chemistry unlike our chemistry is not possible or prevalent. The habitable zone only applies to carbon-based life-as-we-know it. Life could easily be possible using alternative chemistries that can exist on radically different planetary situations.
Then, even taking that into account even life-as-we-know it can exist beyond
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The habitable zone gives us something we can focus on. Sure there could be all kinds of weird and wonderful life forms that can survive on planets far hotter or colder than Earth, but that gives us no scope to limit our search. There are a lot of planets out there so we need to look at the ones which are most likely to have life we'd recognise first.
Sure. (Score:2)
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Of course it is theoretically possible for life to exist outside of the habitable zone. However, we can't know that until it is proven. We have proven that life can exist within the 'habitable zone'. We have not proven that life can exist outside the 'habitable zone'.
If you have a limited budget (and every budget is), and are told to search for life, where would you look? Within the habitable zone. What you would you look for? Data which we know is produced by the life that we know to exist.
Your compl
Wha? (Score:2)
Second, your watermelon analogy doesn't apply because we aren't watermelons. The problem with our habitable zone is it is anthropocentric. If you want to make an analogy it is more like a species of fish, who do a survey of life on their planet and never bot
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Then what is it uninhabitable due to?
Re:So, maybe like Venus? (Score:4, Interesting)
The atmosphere. Move Venus out to the orbit of Earth or even Mars and it would still be way too hot and toxic.
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Life never thrived on Venus.
Do you have any evidence to support this? We don't even know if there is life currently living on Venus, much less in its ancient history. It's doubtful that anything resembling earth-like life lives on Venuses surface, but there could be certainly be life we don't understand yet. It also likely had vast oceans in it's past that have dried up... And as far as earth-like life, the atmosphere of Venus is almost identical to earths pressure and temperature at about 50 to 60km up... although it's almost pure C
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If there is life on Venus it never learned to use photosynthesis to store energy from the sun by converting CO2 into higher energy molecules - if it had there would be a lot less CO2 and a lot more O2. I find that hard to believe, it's an awfully valuable resource, and life has a way of figuring out how to use all resources available. On the other hand, I find it very easy to believe that the initial spark of life comes from a set of extremely unlikely coincidences and many planets, even with ideal condit
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Last I checked, carbon-based life require amino acids to even get started. But that's only for carbonites like us that we know of. Lots of sci-fi (& some fact) has postulated non-carbon base life, with elements such as silicon, boron & even metal based:
http://en.wikipedia.org/wiki/Hypothetical_types_of_biochemistry [wikipedia.org]
First off, we would have to define & agree on what exactly constitutes 'life', which sounds a lot easier than it actually is. And don't even get me started on 'intelligence' or 'sentie
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The Sun is getting hotter and was 25% cooler in the distant past. Quite possibly Venus was earth like at that time. Once the Sun heated up enough to boil Venus's oceans it was game over whether there was life or not.
Another billion or so years the same will happen to the Earth unless we move it. Life as we know it won't survive.
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Overactive volcanic activity has produced a crushing atmosphere in Venus' case - which mixed with its solar exposure, makes it unable to support life as we know it.
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Runaway greenhouse effect. Basically the fate Earth will end up in.
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Yes, we should take a lesson from this! Just look at what happened to Venuvian civilization after they started burning all their fossilized Venuvian dinosaurs!
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Who knows what we might find under Venuvian rock and dirt. We haven't really dug around there yet.
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Who knows what we might find under Venuvian rock and dirt. We haven't really dug around there yet.
Venuvian plastic garbages?
Venuvian disposable diapers??
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Mounds of Venuvian Blue Ray, DVD and CD discs.
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The Sun gets more dense due to converting hydrogen to helium which causes it to put out more heat. In perhaps a billion years the oceans boil, water vapour makes the greenhouse effect higher, limestone and similar C sinks break down, CO2 content goes up, water disassociates into hydrogen and oxygen, hydrogen is lost, oxygen combines with carbon and Earth ends up much like Venus.
Re:So, maybe like Venus? (Score:5, Informative)
Runaway greenhouse effect. Basically the fate Earth will end up in.
No. There's been times in the past when the CO2 levels in our atmosphere were twenty times higher than they are today. The rise since the Industrial Revolution is nothing compared to back then. Of course, back then we had "tropical" climes north of the Arctic Circle, but it didn't lead to a Venus-like runaway greenhouse effect. No, the true horror will be men wearing Speedos on the beach in Point Barrow...
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You shouldn't feed trolls like allcoolnameswheretak. He was either joking or just full of shit. You're quite correct though, the Earth is colder, with more ice, than during most of its history.
unfortunately not only online trolls (Score:2)
Unfortunately, it's not just online trolls; the myth of "runaway greenhouse effects" is strong among global warming activists, including people like Hansen:
http://en.wikipedia.org/wiki/Runaway_greenhouse_effect [wikipedia.org]
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The sun is expanding and will eventually boil our oceans away before engulfing the planet entirely. You mustn't always see things from your paranoid conservative point of view where every comment involving science is out to get you.
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Your comment involved no science though, mine did. Look up some facts.
Also, do not assume someone's political bent from a comment like the one I made. You have no idea about my political leanings, though they tend towards libertarianism, fiscal conservatism, and social liberalism.
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You have no idea about my political leanings, though they tend towards libertarianism, fiscal conservatism, and social liberalism.
i.e. you're a rightwinger who does drugs, like most Americans on slashdot, it seems.
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You have no idea about my political leanings, though they tend towards libertarianism, fiscal conservatism, and social liberalism.
i.e. you're a rightwinger who does drugs, like most Americans on slashdot, it seems.
Wow, two posters with false assumptions in one thread, whodathunkit? I drink a little and take aspirin for headaches, thank you very much, that's about the extent of my drug use. Not all libertarians are druggies, though if someone wants to smoke pot I think they should have the right to (responsibly) do so.
As for right wing, that's laughable. Do you even understand the term? I don't care if gays want to get married. I don't think abortion should be illegal in all cases. I believe in small government
Re:So, maybe like Venus? (Score:4, Interesting)
Of course, back then we had "tropical" climes north of the Arctic Circle
If you think the entire planet was like Hawaii back then, you're sadly misinformed.
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And if you think the entire planet was a burning hellhole, you're also sadly misinformed.
On balance, the planet was probably somewhat nicer for mammals than it is now.
Re: So, maybe like Venus? (Score:2)
Do you happen to have a reference for your theory? The theories I've heard (which are proclaimed pessimistic) say nothing about water splitting due to solar radiation, but rather just evaporating and making its way up to the stratosphere, where it has a higher probability of being lost to space. It also sounds like the time frame for this process is not pinned down.
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You're not taking the long view. In perhaps 500M-750M years from now, the sun's output will have increased sufficiently to have evaporated most of the oceans. The ensuing runaway greenhouse effect will make Earth like Venus. This would have been the case had humans not existed. Life on Earth has almost run its course; if we destroy ourselves and all higher mammals (eg. in a global nuclear war) there's not enough time for another intelligent life to evolve a second time from cockroaches.
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Well, slashdot's a start, isn't it?
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I think what we are pulling out of the ground(ie: Earth's cooled crust) is already out of the 'affects tectonics' range.
Now if we decide to somehow extracting it from the molten core, you may have cause to worry.
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My guess is that we can't extract nearly enough of it to have a noticeable effect on the Earth.
Re:Nuclear Program Reducing Plate Tectonics? (Score:5, Interesting)
Blow up a balloon. Now, look at that rubber covering. That's where we live on the balloon planet. We could mine as much as we want from the crust and literally not even scratch the surface. Now, maybe some day we'll have mantle drilling operations to extract molten materials from deep within the planet, but no, we're not doing that, so no. Besides, Get out your GPS. Wait till a little before the moon is rising or after it has just set. Take a GPS elevation measurement. Then, take one again when the moon is directly overhead. Where I'm at the crust fluctuates ~30cm (one foot), just due to the moon's tidal forces... Massaging the crust like that has to have some effect on tectonics doncha think? Imagine all the friction that flexing causes...
Re:Nuclear Program Reducing Plate Tectonics? (Score:5, Insightful)
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My meteorology instructor said, "Take a basketball, and assume the Earth is that size. The bumps are higher than Everest and the valleys are deeper than the Challenger Deep, but it will do. Dunk it in a bucket and pull it back out. See that sheen of water on the surface? That's the breathable atmosphere." That's always stuck with me.
I'm glad you said "breathable atmosphere" rather than just "atmosphere". Something that most people don't seem to get is that it's very very hard to define the "limit" of our atmosphere (or indeed that of most planets that have one).
The exosphere (by no means "breathable", but still measurably part of our atmosphere) extends to 10000km away from the surface, which is only slightly less than the diameter of the Earth itself (12750km) and somewhat over a quarter of the way to the moon. The mesosphere goes u
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er... 10000 km is "somewhat over a quarter of the way to the moon"? if you really think that the moon is only about 4 earth diameters away from the earth, your mental model of solar system needs a serious recalibration! :)
Heh... actually, it was a severe brain-fart moment... my brain said "a fortieth" and my fingers came out with "a quarter" somehow.
So yeh, mea culpa. But thanks for setting the record straight in case anyone was to read that silly mistake and end up believing it.
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No, warmer would be bad.
A warmblooded animal, such as mammals with their core temperature of ~37ÂC for mammals and few degrees more for birds, constantly produces heat. That is heat must go somewhere, otherwise it would lead to overheating. So the only choice is to run at a temperature which is above that of the environment. Once those temperatures come too close to each other, all animals reduce their activity more and more to prevent said overheating.
So, a jump in global temperature, i.e. one that is
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Yes, that's why every human and every other animal at or near the equator is dead today.
Oh. Wait.
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Yes, that's why every human and every other animal at or near the equator is dead today.
Oh. Wait.
He said they reduce their activity. Ever hear of a siesta? It's one thing for temperatures to hit around 100F during the middle of the day, it's quite another for that to be the night temperature and a significantly higher temperature during the day. There's a reason that so many equatorial mammals are nocturnal or crepuscular -- it's too hot during the day to do anything but sleep in the shade/water.
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Two centuries ago, it was known that some animals went much faster then 35 mph, a century ago people had been flying for over a hundred years and it was obvious that birds and such flew even though they were heavier then air. 50 years ago people were writing stories with compact computers in robots.
The only new physics needed for all the above was quantum theory and the transistor. Perhaps there is physics that allow removing inertia but we have no hints of it unlike quantum theory where hints (electricity,
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Two centuries ago I'm sure someone said, "Barring some tremendous breakthroughs in physics, no one's going faster than 35 miles an hour." Barely a century ago they were saying, "Barring some tremendous breakthroughs in physics, no one's going to fly." Half a century ago they said, "Barring some tremendous breakthroughs in physics, no one's going to have a computer in their home." Physics changes bitches, get over it.
This is the classic space nutter argument:
All we have to do is discover how to travel faster than light/tap into unlimited quantities of energy, and we can start to colonise the stars!
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Isn't almost everywhere more dynamic than Ohio?
Not in an election year, they aren't!