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## Excellent Exoplanet Illustration

 Quote by mheslep Direct high resolution imaging of planets never seen before would be a return to the sense of discovering what's out 'there', the way it was at the time of the first Moon landing, and in multiple ways: i) is this really doable?, ii) what will we see? There's little question that, for instance, a manned mission to Mars is technically possible, given the will to spend ~$500B,$1000B, whatever it may be, on ~five elite humans.
Direct imaging of planets, like we do with Jupiter, Saturn, etc currently, is out of the question at the moment. The size of the mirror you would need to be able to obtain the required magnification, light gathering, and resolution is...crazy huge. MUCH bigger than we could possibly launch into orbit. Ground telescopes would be limited horribly by atmospheric turbulence, and although we have adaptive optics, they don't approach the scale of this kind of telescope.

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 Quote by Ryan_m_b ... Perhaps it's due to ignorance but I'm unaware of any possibility that exoplanet observation could go beyond determining very general attributes of a planet i.e. atmosphere make up, surface temperature etc. We might have some indication of life or at least the planet having the appropriate characteristics but even if it were teeming we wouldn't be able to tell anything about it.
Well that was my thought as well until I saw what's been done so far with imaging on ground based telescopes. I also read that, for instance, the spectral lines of photosynthetic chemicals are very distinctive.

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 Quote by Drakkith Direct imaging of planets, like we do with Jupiter, Saturn, etc currently, is out of the question at the moment. The size of the mirror you would need to be able to obtain the required magnification, light gathering, and resolution is...crazy huge. MUCH bigger than we could possibly launch into orbit. Ground telescopes would be limited horribly by atmospheric turbulence, and although we have adaptive optics, they don't approach the scale of this kind of telescope.
You missed the point of my first post, which was to question not whether this was possible now, but would it be possible even a century from now given the resolving power needed and the contrast problems. I originally thought no, given the 'shadow box' techniques in use for many of the detections. But some of imaging work done so far is impressive.

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 Quote by mheslep Yes of course there's diffraction but are you sure about the resolution? The planet scales shown in the picture are roughly correct according to the measured data, which lists those planets as roughly 1/15 the diameter of the star. How many pixels do you credit to the star? http://exoplanet.eu/star.php?st=HR+8799
Probably about 1 pixel.

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 Quote by mheslep You missed the point of my first post, which was to question not whether this was possible now, but would it be possible even a century from now given the resolving power needed and the contrast problems. I originally thought no, given the 'shadow box' techniques in use for many of the detections. But some of imaging work done so far is impressive.
If that was your point then I'd say you need to clarify a little. Anyways, most of the "shadow box" techniques are designed to block the light from the star so that we can see the light reflected from the planets effectively without the star's light overwhelming the entire image.. This only requires enough resolving power to give good separation between the star and it's planets in the image, so it is far easier than trying to actually see the detail on any of the planets.

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 Quote by Drakkith Probably about 1 pixel.
Clearly Sun sized stars at 140 ly can be resolved better than 1 pixel by Keck.

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 Quote by mheslep Clearly Sun sized stars at 140 ly can be resolved better than 1 pixel by Keck.
I just did the math, and while I'm not sure I was 100% accurate, when my numbers give me about 30 millionths 300 millionths of an arcsecond (0.0003)for the angular diameter of the star, I feel confident enough to run with it. If you disagree then please, do the math, as I would like to know if I did it correctly.
 NASA has a proposed mission, called TPF (Terrestrial Planet Finder) to image exoplanets. There are two main concepts, TPF-I, based on an interferometer, and TPF-C, based on a coronagraph. Here is a web site: http://exep.jpl.nasa.gov/TPF/tpf_index.cfm

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 Quote by Ryan_m_b That's why I asked about near future projects, it will be facinating to see what the state of exoplanet exploration is like over the next few decades. How many will we have found? What will we be able to tell about them beyond their size, mass and distance from their sun?
In the next years, I would expect many more planets by Kepler, with some contributions from other telescopes.
After that, Gaia is designed to detect some tens of thousands of exoplanets. The downside is that many of them will be hot Jupiters, as the large number mainly comes from the immense amount of observed stars. However, I think the number of known smaller planets will explode, too.
In 2020 +x years, new earth-bound telescopes (E-ELT, TMT, GMT) should be able to perform spectroscopy at earth-like planets (and others, too, of course). Some gas compositions could be a good indication of life. Apart from SETI (which requires aliens sending messages around), this will be the first time in human history where we have a realistic possibility to detect extraterrestrial life. And this is just ~15 years away!
 Recognitions: Gold Member ‘Close encounter’ planets discovered by NASA’s Kepler Telescope NASA’s Kepler space telescope has spotted two planets engaged in an odd dance with each other, say scientists, a finding that is a first for the U.S. space organization and astronomers everywhere. The finding, which was first reported in the June 21st Science Express, notes the appearance of a pair of planets engaged in a tight orbit with one another. Kepler-36, which is located approximately 1200 light-years from Earth, has two planets with vastly different densities orbiting close to each other. Astronomers believe that Kepler-36c might appear more than twice the size of the moon in the night sky of Kepler-36b. http://www.thebunsenburner.com/news/...ler-telescope/
 That's art! (For me) ;) Although it's wonderful that they've been able to detect those big gas giants. However I can't wait until they find exomoons and smaller bodies. Such as Earth in a bigger amount.
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