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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."
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.
Cassini is probably not designed to be sensitive to those signatures. It's built for Saturn and co. It cost a lot to add & launch extra's outside of mission objective.
Table-ized A.I.
Until the point that American Idol and Fox News is detected ;-)
Table-ized A.I.
It looks like they focused on only measuring certain atmospheric things, but this proves nothing as far as extrasolar planets go.
Free oxygen on any planet tells you that something is making oxygen. In our case it is the plants which we treat so badly: turning them into newspapers, etc. Oxygen is so reactive that its presence tells you something must be going on. Mars used to have free oxygen but it combined with iron in the soil, turning it red: Iron Oxide.
http://michaelsmith.id.au
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!
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)
People are chucking around the idea of life on Titan, with Hydrogen taking the place of Oxygen. The thing you have to look for is an environment out of balance. Plant life on Earth turns sunlight and carbon dioxide into oxygen. Our free oxygen gives the game away and would be obvious to a good telescope many light years away. I think we would look first for free oxygen, but other combinations would raise alarm bells too.
http://michaelsmith.id.au
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.
Thank God we have enlightened ACs teaching scientists how to do things! I'm sure they never considered the points you raised.
To address your point: they do NOT assume that life needs oxygen. However, the presence of significant amounts of oxygen in a planetary atmosphere is a strong indicator of life. This is because the gas is so reactive that it gets removed from the atmosphere very quickly. The only reason we have oxygen in our air is because it is continuously put there by photosynthesis.
they're not saying life can only develop this way. but if they find an earth-like planet, there's a pretty good chance it might have life. by the way, they're looking for habitable planets, not life.
the science of a class of systems "X" is always hard when you have just one example; there's no need to call them stupid.
new sig
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.
The Slashdot summary was really, really bad. They didn't pretend to be observing the earth from the moon, they analyzed the spectra of light passing through the earth's atmosphere and reflected off of the moon. The idea is that this is similar to analyzing the light passing through a planet's atmosphere as it transits in front of a star. So it's not as crazy as it sounds.
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.
And besides, finding life that uses oxygen means we're more likely to find life similar to ours, so we can have sex with it.
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.
It looks like they focused on only measuring certain atmospheric things, but this proves nothing as far as extrasolar planets go.
Free oxygen on any planet tells you that something is making oxygen. In our case it is the plants which we treat so badly: turning them into newspapers, etc.
The issue is burning down large areas of rain forest to get more short-term farmland, which uses up oxygen as well as permanently destroys the source for oxygen. The newspaper is not so relevant, since it is partially recycled and partially grown for the purpose.
NB: The message above might reflect my opinion right now, but not necessarily tomorrow or next year.
extras
Tempora mutantur, nos et mutamur in illis