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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."
journalism is intended for easy digestion. criticizing journalism for not getting science accurate is actually a sign you don't understand what the purpose of journalism is
the constant harping on slashdot against journalism for not getting every technical detail accurate and in context is, frankly, stupid. on YOUR part. unless journalism is lying, or saying things completely misleading and way off base, not being entirely accurate is 100% fine. the purpose is COMMUNICATION, not RESEARCH PAPER ACCURACY
look at it this way: how would you describe this issue to a curious seven year old? would the words "earth-like" be acceptable? yes? then this is a completely ridiculous topic, drop it
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
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".
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.
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
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.
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.
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.
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.