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Where Would Earth-Like Planets Find Water?
astroengine writes "The term 'Earth-like worlds' is a vastly overused and hopelessly incorrect term that is popularly bandied about to explain some recent exoplanet discoveries. Although some of the distant small worlds being discovered by the Kepler space telescope may be of Earth-like size, orbiting their sun-like star in Earth-like orbits, calling those worlds 'Earth-like' gives the impression these alien planets are filled with liquid water. It turns out that we have only a vague idea as to where Earth got its water, and it will take a long time until we have any hint of this life-giving resource on worlds orbiting stars thousands of light-years away."
The whole nonsense of even using the term "earth-like" is a joke, born of the press and PR-minded astronomers. Calling a planet "earth-like" implies way more than correlation with earth's size and it's orbit around the sun. There are so many characteristics which may well make the earth a very unique planet. It's not just the presence of water, either--it's also our magnetic field, the presence and effects of our moon, the nature of our core, etc. It could very well be that true earth-like planets are VERY rare in the universe. Though the shear size of the universe suggests it's likely there are other planets out there like ours and other life out there, it's probably a LONG way to our nearest earth-like neighbor--and likely a much longer way than even that to the nearest planet with similar intelligent life living coincidental with us.
Much as I hate to say it, having grown up on space dreams and science fiction, the more I learn about space the more I've become convinced that, for all intents and purposes, we're basically alone on this little blue ball. When I used to dream otherwise, I really had no real appreciation of just how vast and empty space really is, for one thing. I think the popular perception is that the next solar system begins close to the edge of our own (I certainly thought so when I was a kid watching sci-fi movies). In reality, every solar system is a tiny isolated island in a giant lonely ocean. A space probe that takes 9 years to go from earth to Pluto would take over 100,000 years to get to even our closest neighbor, a mere 4.2 light years away. And that's in a universe that's 15 *billion* light years across. It's a big place, with an unimaginable number of other planets. But mostly it's just a giant, empty void.
So there are probably indeed other earth-like planets out there. But barring some incredible technological advances (probably thousands of years worth) and a complete overthrow of Einsteinian physics, no human is ever going to see them or even be able to communicate with them.
This is usually the part where I make a joke, but somehow I just feel lonely and sad now.
SJW: Someone who has run out of real oppression, and has to fake it.
This is usually the part where I make a joke, but somehow I just feel lonely and sad now.
Maybe this will do - one of my old sigs:
"Space - it's really big. I mean, really, really, really big. Better pack a lunch."
It's easier to be a result of the past, but more fun to be a cause of the future! http://www.spacefinancegroup.com/
That was my response as well. Whereever Oxygen and Hydrogen exist, the problem is NOT creating water. In fact, it's very likely that the largest source of water outside of the Earth in our Solar System is orbiting Saturn.
SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
If it's filled with water, then it's definitely not Earthlike, if the OP is going to be a pedantic killjoy, then at least get the facts right.
"The term 'Earth-like worlds' is a vastly overused and hopelessly incorrect term"
"Earth-like worlds" is not an incorrect term. Misused perhaps, but not incorrect.
... but somehow I just feel lonely and sad now.
/.
Welcome to
How about a basic classification scheme for planets?
http://en.wikipedia.org/wiki/Class_M_planet
Except do it better. World size, composition, orbit, etc.
Then, instead of reporting about another "Earth-like" planet they could report on a class blah-blah-blah-blah planet that MAY be "Earth-like".
Forgive my ignorance, but why do we always seem to presume alien life has to be hydrocarbon bases like ourselves? Couldn't their metabolism be based on some other chemical process?
The whole nonsense of even using the term "earth-like" is a joke, born of the press and PR-minded astronomers. Calling a planet "earth-like" implies way more than correlation with earth's size and it's orbit around the sun. There are so many characteristics which may well make the earth a very unique planet. It's not just the presence of water, either--it's also our magnetic field, the presence and effects of our moon, the nature of our core, etc. It could very well be that true earth-like planets are VERY rare in the universe.
Or it could be that we're _not_ so lucky, that these are fairly common, or turn out to be much less essential than we thought. Since we can't measure those remotely (yet), we have no way to stake a solid claim either way.
So what's wrong with "Earth-like" when referring to planets of which every parameter we _can_ remotely measure at present (thus all the ones we _know_ are scarce) match? Only illiterate fools would choose to infer similarities that we couldn't possibly know from that, and frankly they'll misunderstand no matter what terminology you use.
That was my response as well. Whereever Oxygen and Hydrogen exist, the problem is NOT creating water. In fact, it's very likely that the largest source of water outside of the Earth in our Solar System is orbiting Saturn.
You may be right about the source being other moons. Comets are another potential source, Louis Frank published his theory in The Big Splash, but it never seemed to gain a lot of traction, even though the guys has a lot of credentials. It was generally disregarded, like so many other novel theories.
In the book he postulates that thousands of small fluffy snow-ball comets with no hard central core and which which don't really show up in radar or visually, deposit tons of water on the earth's atmosphere and the moon every year. He even had images in his book about impacts on the moon.
Sig Battery depleted. Reverting to safe mode.
Finally, some common sense on this. Not only is there the question of water, but also whether a planet has a magnetic field which protects atmospheric loss to it's sun's solar wind. Yes, the term "Earth like" is overused.
Another overused term is "God particle".
Proverbs 21:19
Let me cheer you up with a quote from the Hitchhikers Guide to the Galaxy...
POPULATION OF UNIVERSE : None.
It is known that there are an infinite number of worlds, simply because there is an infinite amount of space for them to be in it. However, not every one of them is inhabited. Therefore, there must be a finite number of inhabited worlds. Any finite number divided by infinity is as near to nothing as makes no odds, so the average population of all the planets in the Universe can be said to be zero. From this it follows that the population of the whole Universe is also zero, and that any people you may meet from time to time are merely the products of a deranged imagination.
we'll find it by surprise, in some ferrous sulfate or ammonia based medium, or whatever:
http://en.wikipedia.org/wiki/Hypothetical_types_of_biochemistry
in terms of random chance, water is the most accessible medium for complex chemistry, and therefore life to evolve in, by orders of magnitude. however, it's not the only medium that can work, so there's plenty other little nooks and crannies to look into
basically, some chemists and physicists should get together, and say: for pressure X and temperature Y, solvent in which complex chemistry can evolve Z is possible. then look for those places, not just water
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
No one expects journalism to give us complete technical breakdowns, but science journalism has a nasty history of not just skimming over important details, but also of out-and-out sensationalism. Take your average report on some hominid fossil discovery, which by the time it gets through the editorial department has a headline "Map Of Human Evolution Redrawn!"
The world's burning. Moped Jesus spotted on I50. Details at 11.
Spreading ourselves around the solar system might be a good idea insofar as it will reduce the probability that we kill ourselves. However, the resources that would be required just to set up a permanent colony on the moon are enormous, and there are a lot of other pressing needs competing for those resources. Frankly, I would not be surprised if the manner in which those resources are obtained triggered the sort of species-destroying war that setting up the colony was meant to mitigate.
For the near future, this planet is it, barring substantial improvements in technology. If we need to choose between a billion dollars spent establishing a colony on a celestial body or spent on developing sustaining methods of producing food in impoverished nations, the production of food must take precedence.
Palm trees and 8
I think the trouble with finding truly alien life wouldn't just be the distances involved, communication, etc. I think it might prove difficult for two radically different alien lifeforms to even PERCEIVE one another. Sort of a "Sir, it turns out that those things we thought were rocks were actually intelligent lifeforms that just move REALLY slow" kind of thing.
SJW: Someone who has run out of real oppression, and has to fake it.
right, and that's exciting, and perfect for digestion by those people who will never care or be interested in the accurate details
so there's no harm. people need a gee whiz component. give it to them. science should not be completely inaccessible
because, if we abide by your standards of communication, what is said about science by scientists will be ignored: too dry and boring. and what is said in popular media will be taken over by those with anti-science agendas, and their lies and distortions will be believed. if we abide by your standards of communication
so inaccuracy is acceptable. raise your tolerance level. communicating the excitement is the most important thing
thinking like you is arrogant, and that's what people will understand about science and scientists. and they will come to dislike it and distrust it, and they will trust the charlatans and the antiscience liars, because they will speak their language
you really need an attitude adjustment. but so do a lot of scientists, when it comes to communicating with the common man. in the service of making science acceptable, accesible, exicting, and friendly, to the common man
or next you will wonder why the peasants are standing outside your offices with torches and pitchforks. or why your daughter is dying of whooping cough because herd immunity isn't protecting her anymore because people aren't immunizing the kids anymore. the proper reaction is not anger or arrogance at the "dumb"folk, but patience, kindness, respect, and COMMUNICATION
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
If we need to choose between a billion dollars spent establishing a colony on a celestial body or spent on developing sustaining methods of producing food in impoverished nations, the production of food must take precedence.
I fail to see why the food needs of impoverished nations is more significant an issue for wealthy nations than the establishment of a permanent colony on another celestial body. The long-term viability of our species is far better served by expanding than trying to feed every child in the Sudan.
There is such a term like Earth analog which is the synonym for Earth-like planet (I found it in Wikipedia and the first poster should try using it), there are no good specifications inside that specific article, although the round talk under "Attributes and Criteria" is quite similar to the above posters.
http://en.wikipedia.org/wiki/Earth_analog#Surface-water_and_hydrological_cycle
How about somebody define it then?
There is something a little bit more specific in:
http://en.wikipedia.org/wiki/Earth_Similarity_Index
- At least you can say for sure that KOI 736.01 has Earth Similarity Index (ESI) of 0.98 and Standard Primary Habitability (SPH) of 0.63.
Christmas and contemplating the scale of the universe always gets me down.
SJW: Someone who has run out of real oppression, and has to fake it.
[quote]And that's in a universe that's 15 *billion* light years across. It's a big place, with an unimaginable number of other planets. But mostly it's just a giant, empty void.[/quote]
Yakko: Everybody lives on a street in a city
Or a village or a town for what it's worth.
And they're all inside a country which is part of a continent
That sits upon a planet known as Earth.
And the Earth is a ball full of oceans and some mountains
Which is out there spinning silently in space.
And living on that Earth are the plants and the animals
And also the entire human race.
It's a great big universe
And we're all really puny
We're just tiny little specks
About the size of Mickey Rooney.
It's big and black and inky
And we are small and dinky
It's a big universe and we're not.
And we're part of a vast interplanetary system
Stretching seven hundred billion miles long.
With nine planets and a sun; we think the Earth's the only one
That has life on it, although we could be wrong.
Across the interstellar voids are a billion asteroids
Including meteors and Halley's Comet too.
And there's over fifty moons floating out there like balloons
In a panoramic trillion-mile view.
And still it's all a speck amid a hundred billion stars
In a galaxy we call the Milky Way.
It's sixty thousand trillion miles from one end to the other
And still that's just a fraction of the way.
'Cause there's a hundred billion galaxies that stretch across the sky
Filled with constellations, planets, moons and stars.
And still the universe extends to a place that never ends
Which is maybe just inside a little jar!
YW+D : It's a great big universe
And we're all really puny
We're just tiny little specks
About the size of Mickey Rooney.
You might think that you're essential
Try inconsequential
It's a small world after all!
Kwisatz Haderach
Sell the spice to CHOAM
This Mahdi took Shaddam's Throne
You'd need to pack a fully self sustainable colony. Lunch would barely get you to orbit.
Doesn't matter. By the time we reach any planets in other solar systems we won't need water to survive. We'll have transferred our brains to computers and will use whatever android bodies are suitable for the terrain.
I know, sounds fanciful, but it's more realistic than to think that we'll be sending human beings to other solar systems. The amount of oxygen, water, food, and other resources required - even if we invent some kind of suspended animation - makes it laughably unlikely.
Where Would Earth-Like Planets Find Water?
Uh, how about in the ocean..?? Or in the creeks, streams and rivers?
Or maybe they could just-- you know-- turn on the tap and out it comes.
You did specify "Earth-like"....
I pretty much have the same story as you. Early believer, but then I came to realize the the dimensions of space and how slow our spacecrafts are. On top of that, it seems unlikely that, due to time dilation, any travel by current and near future physics will be moot. I am saying even if you can travel at 10% light speed or a hundred thousand times that, when you come back, everyone you knew will be dead and your research could be completely worthless. Sad but true.
Can I light a sig ?
And a Merry Christmas to you, Mr. Scrooge!
SJW: Someone who has run out of real oppression, and has to fake it.
Wouldn't even need much of a spark. Water WANTS to be water.
SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
Christmas and contemplating the scale of the universe always gets me down.
Didn't get that scale model of the Enterprise again?
Maybe next year.
Faster! Faster! Faster would be better!
Actually, no, that's about it. The problem is people are screwing that up.
Yeah, wrong. And communication is trivial for anything close enough for imaging.
The word "Like" is relative. Relative to the past frame of reference. The second time you see a gorilla, you think it looks like the first gorilla. I suspect I would be hard-pressed to tell a male gorilla from a female on casual observation. Jane Goodall, however, probably sees as much visual distinction between individual gorillas as you see between humans.
Same with exoplanets. The first ones we detected were supergiants in close orbits around relatively small stars. Compared to those, Mars is Earth-like. Now we've found enough that "Earth-like" is evolving to mean something more specific. Vague terms in novel and rapidly advancing fields have evolving meanings. That is the nature of language.
As others have said, exoplanet taxonomy is a fine new field to plumb, but that doesn't mean Earth-like is bad -- it's just vague and unscientific. A rough measure that only has meaning in context. Conversational shorthand, useful in casual discourse.
A quick look around finds that there are people working on formal taxonomy.
Stop-Prism.org: Opt Out of Surveillance
Don't feel bad. It just means we're responsible for becoming the extraterrestrials. We need to seed the universe with humanity (and as many other intelligent species as we can can help get liberated from this little mud ball.) There are countless fascinating environments in this solar system alone. Wealth and resources to beggar the imagination. With a commitment to space faring, we could have sustainable habitats all over the solar system in this century.
With the building materials available in the Asteroid Belt, Kuiper Belt and Oort Cloud, we could scatter sentience across the stars. We might master faster than light travel. We might not. We would certainly be able to ensure that whatever cataclysms that befell earth in the near or distant future, sentient life would continue to exist, and the earth's greatest gift to the universe would persist.
Maybe, one day, millions of years from now, when we fill the Orion arm of the Milky Way galaxy, and have found ways to utilize any kind of matter we come across to sustain ourselves, we will bump into another sentient life form. However, there will be no time when we are alone, because we will have each other.
For the near future, this planet is it, barring substantial improvements in technology. If we need to choose between a billion dollars spent establishing a colony on a celestial body or spent on developing sustaining methods of producing food in impoverished nations, the production of food must take precedence.
The thing is, we don't get to choose between a billion dollars spent here and a billion there. IMHO before we can even argue about where money gets spent, we, as a country (I'm referring to the US, you said dollars :P), need to get our priorities straight. As a country we have access to an absolutely HUGE amount of money; we just need to take it. With the proper government in place, we could advance our quality of life AND our [space] technology without even having to choose one over the other. It would, unfortunately, require a massive cultural change to a more scientific and activism oriented society.
And of course, this is obligatory: http://en.wikipedia.org/wiki/Military_budget_of_the_United_States
But seriously, when are we going to do something about it?
Wrong on both accounts.
There are actually twice as many even numbers than odd ones.
Proof:
Assume any even number "n", so
n * n = [even]
n * (n-1) = [even]
n * (n-2) = [even]
Now take any odd number "m":
m * m = [odd]
m * (m-1) = [even]
m * (m-2) = [odd]
So out of any two odd/even numbers you can generate twice as many even numbers compared to odd numbers.
q.e.d.
(and yes, for the non-maths out there, it is a joke)
There are fewer illiterates than people who can't read.
That assumes the priority of the wealthy nations is the long-term viability of our species. Considering the number of policies implemented that jeopardize the long term sustainability for the short term profit, I doubt that is the case.
I predict we will continue to waste that money in stupid bullshit instead of doing either.
Dilbert RSS feed
Please don't anthropomorphize water; it hates when you do that.
Dilbert RSS feed
Christmas and contemplating the scale of the universe always gets me down.
You might think it's a long way down the spiral arm to the Lesser Magellenic Cloud, but that's just peanuts to Christmas.
You are not a brain: http://books.google.com/books?id=2oV61CeDx-YC
. . .contemplating the scale of the universe always gets me down.
It's interesting that people feel that way. Personally I find it comforting to realize that the universe is so much larger than I am that I couldn't possibly be an important part of it. A study of the cosmos actually helps me focus on life in the here-and-now, to respect and enjoy the progress made by those who came before me, and to value the company of the humans around me, on the grounds that these things are all I'll ever get to experience.
IMO, astronomy and cosmology are worthwhile pursuits, not because of what they tell us about the stars, but because of what they tell us about ourselves. Through these sciences we've come to understand that the Universe sees us the way we see atoms in the antennae of ants, if the Universe contemplates us at all.
It seems important for humans to get past the idea that we serve a mystical universal entity with specific plans for us as individuals. Put simply, in the post-nuclear age, humility is a survival tool. Letting go of one's sense of cosmic self-importance should be a liberating sensation, not a depressing one.
How about what has already been found out there:
Most Distant Water in the Universe Found
and
Evidence of Water in Atmospheres of Planets Orbiting Distant Stars
And I hear we've only been doing this planet finding stuff successfully for a little while.
The problem isn't the existence of water before the formation of the Sun, it's why it's still here. First, the young Sun would clean the space around itself from excess material with an intense solar wind. The Giant Impact to form the moon would convert the Earth into a magma ocean, again not much helping with water retention. Over time, the solar wind and ultraviolet radiation destroyed the water in all other planets close to the Sun. In the inner solar system, all unprotected water will eventually evaporate, dissociate into hydrogen, and the hydrogen will be blown out from the solar system by solar wind. We know that Earth's magnetic field protects from solar wind, but the problem is still where did the original water come from - was it already here, or was it imported from the outer solar system? It's like we're in the middle of a desert, but we still find water where we are.