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Earth As an Extrasolar Planet
sciencehabit writes "Astronomers have a theory that they can detect whether a planet light years away will be habitable by just looking at how its sun is reflected in its atmosphere. To test the idea, they pretended that they were observing Earth from a distant object — in this case, the moon. And sure enough, they picked up critical components for life in Earth's atmosphere: ozone, oxygen, sodium, and nitrogen."
Why not point Cassini back at us and take some readings.. that should also give some good results.
"Freedom in the USA is not the ability to do what you want. It is the ability to stop others from doing what THEY want"
http://en.wikipedia.org/wiki/Jupiter#Possibility_of_life
http://www.youtube.com/watch?v=uakLB7Eni2E
http://www.thelivingmoon.com/41pegasus/02files/Critters_Carl_Sagans_Cosmos_Life_on_Jupiter.html
Besides extremophiles, there may entirely new systems of life.
NASA has finally proved that planet Earth is (still, at least) habitable! We knew that all that investment will bring us new knowledge some day.
From the moon, you have a pretty good view of earth. You can make out oceans and continents, and even manmade features if you have a good telescope. It looks like they focused on only measuring certain atmospheric things, but this proves nothing as far as extrasolar planets go. The distances involved make the earth-moon distance a piss-poor analogy for drawing any conclusions from this about anything light years away.
Until the point that American Idol and Fox News is detected ;-)
Table-ized A.I.
wHo says that life needs oxygen? Even on our planet are living beings who do not need oxygen at all. Black smoker bacterias for example.
Life develops according to outer circumstances. Darwin. Read it.
it's just plain stupid to believe extra-terrestial life can only develop on Earth 2.
This technique only works on light that passes through the planet's atmosphere. In this case, during a lunar eclipse, they pointing a telescope at the part of the moon that was reflecting the light that had traveled through the Earth's atmosphere. They found that the moon had absorption lines resulting from interactions with Earth's atmosphere.
The technique would work if the Earth occulted the Sun from Cassini's viewpoint, but such occultations are rare.
It's natrium, you insensitive clod!
So they take Earth, which has life, and use that to train up an algorithm to detect if other planets have life. Then they test this algorithm against... earth.
This is not how you're supposed to train systems. You need to keep your training and test data separate. Couldn't we have at least thrown one of those self-sustaining fish-globes up into space, and test that for life?
The ______ Agenda
Astrophysicist Alfred Vidal-Madjar and colleagues at the Institut d'Astrophysique de Paris decided to test the idea...
Granted, NASA does have the firepower and crack soldiering skills necessary to invade and occupy Paris, but they haven't done it. (yet)
They are testing techniques for detecting elements that may signal the existence of life as we know it. You have to learn to walk before you learn to run.
If everyone had your attitude we'd still be living in caves and worshiping the spirits all around us.
"A search for life on Earth from the Galileo spacecraft", Nature, 1993 C. Sagan et al., http://www.nature.com/nature/journal/v365/n6448/abs/365715a0.html
I for one welcome our new Earth overl-...... wait a second.....HEY, that's me!
soylentnews.org Go there to enjoy the people!
This is spectroscopy. They've been doing it for years, and it is the reason we know the chemical composition of everything from stars to planets to gas clouds. It's a fundamental tool of astronomy. The only novelty re: extrasolar planets is the resolution required, but even that isn't new, afaik.
The article quotes the boffin as saying
"The surprise was that we succeeded with extremely sparse observations under relatively bad weather conditions," Vidal-Madjar says. "But seeing how easily oxygen was seen strongly argues in favor of high-spectral-resolution searches [of Earthlike extrasolar planets]."
So it seems that the news here is that it's easier than expected to measure oxygen.
The English word fart is one of the oldest words in the English vocabulary.
So, now to apply this to an extrasolar planet, we have to have the planet reflect the light of its sun back at the Earth, which means that their sun is already between them and us (counting "between" as being able to project the vector from here to their sun upon the vector from here to the extrasolar planet, and result in a vector of lesser magnitude than the vector from here to the extrasolar planet). And we're supposed to be able to isolate any of the light from that planet apart from its sun?
You misunderstand the experiment. For this idea to work, the planet has to be between us and the star. Exactly between - as in, the planet is eclipsing its sun, from our point of view. They're not detecting light that's been reflected off a planet, they're detecting light that's been filtered through a planet's atmosphere.
This is something we've already done with large gas giant planets. The 'new' thing is that we did it with a planet the size of earth, with its significantly thinner atmosphere.
The researchers formulated a hypothesis based on first principles ("training data"), then tested that hypothesis by applying it to earth ("test data"). So, they didn't mix training and test data.
Hmmm.
Sodium (Na) a necessity in the atmosphere of a planet in order to make life (in a form similar to the one we know) possible?
If so, what about the minimal content of Tungsten (again, in a planet's atmosphere)? Barium, anyone's guess?
Just wondering...
Now if only people, including Scientists of all fields, would realize that Heaven already exists and anyone that is alive is living in it. It is called planet EARTH.
No other place in the known universe has such a perfectly tuned atmosphere, able to support intelligent life. Let alone any type of life. Below is a list of traits the Earth has, which are rare, yet essential for life to spawn and be sustained.
1) A large moon to make stable the earths rotation (seasons), make oceans slosh which is said to have helped stir up the primordial soup to create chemical life.
2) A magnetosphere. Most planets/moons do not have one. Without one the atmosphere would blow away due to solar wind from the sun. Mars as an example.
3) In the goldie locks zone. Only Earth and Mars are known to exist in one, keeping water as a liquid. Not too close or far from the sun.
4) Orbiting a fairly stable Star called the SUN. Most stars are too large and burn out too fast.
5) Calm solar system, with very few cosmic impacts from comets/asteroids, allowing life to evolve and thrive in time for us to create anti-asteroid technology.
6) Earth is not too large or too small. If too small will cool down too fast and loss it's molten core and hence Magnetic Field. Example is Mars.
7) Jupiter did not ignite into a star. (Did not have enough mass) Yet, jupiter is large enough to vacuum up many objects that could have hit the Earth and killed us.
8) Large amounts of H20, carbons, Nitrogen, Iron, etc. Life needs a nice mix of elements to create an Atmosphere and life. Missing a key element and life would not be.
9) Solar system not too close to other stars/clusters to avoid Super Nova's and other hazardous stars which could kill us all.
10) Pure chance that anything else I missed that Earth has going for it to allow life to Evolve and invent technology to allow Internet and myself to type to YOU.
Now, you tell me if Earth is not a Heaven? Tell me that all of these things are not extremely good things to have happened to Earth and whether or not you think we are damn lucky yo even be alive. If not, you need to seriously consider looking into science more and learning about all the amazing things the Earth has going for it to allow you to exist at all.
We are all in Heaven as far as I am concerned. It was in front of our face the whole time, if one only puts down the ego and learns about these things.
Think about worms; they eat the earth, but in the process they make the earth more aerated and more suitable for worms to live in, as anyone with a compost heap can attest.
I think this ties in nicely with the idea of Ilya Prigogine that life is a process which is thermodynamically far out-of-equilibrium, i.e. a steady state: as long as you feed a lifeform (e.g. sunlight if it is a plant) it lives, but when it has no more food it dies, i.e. reverts to chemical equilibrium.
If you combine both ideas, you can get to the point I want to make:
It seems the gist of this article is a bit how occultation gives a good opportunity to take the spectrogram of a planet, but I think they missed saying why finding an out-of-equilibrium atmosphere is an indicator of possible extraterrestrial life.
To be, or not to be: isn't that quite logical, Slashdot Beta?
You were never taught about pretending were you?
“Common sense is not so common.” — Voltaire