Slashdot Mirror
Terrestrial Planet Finder
solarlux writes "The Terrestrial Planet Finder has taken one step closer to reality as two architectures have been approved by NASA. The first, TPF-c, will be a single optical telescope which employs a coronograph to block starlight for planet detection. TPF-i will be a flotilla of infrared telescopes flying in formation to form a interferometer. TPF-i will analyze the planets identified by TPF-c for life signatures. The telescopes are to be launched within the next 10-15 years."
By then SETI might have actually found something. Remember, it intelligent life isn't dependent on a planet. Any advanced race probably left their world eons ago.
BLING BLING. Meet the architecture that's changing everything.
Once these things start piling up spectra. We could get some great surprises. Anyone wonder how things are going to change if they find a planet with a big chuck of oxygen in the atmosphere. Yet more proof that we're not quite so special :).
Glad to see everyone staying optimistic about these things!
Some of us still want conclusive data on IF, and if so, HOW MANY Earth-like planets there are out there - on the theory that extraterrestrial life is more likely to be found if there are other worlds out there like ours (we know *this* system works, we don't know what else *might* work).
The case for ETI is much stronger if you can show that there ARE many many Earthlike worlds in the universe, compared to the present, where we can say "there MAY be many, with this set of assumptions, or ours may be the ONLY one, if you use this other set of assumptions."
Xentax
You shouldn't verb words.
I'm sure it's important and useful to gather information about the planets and other cosmic objects around us - since they help in understanding how we have come here and how our planet was formed.
An offshoot of this perhaps also helps us understand the weather, and provides knowledge about freakish changes (high tides in full moon, etc).
Having said all this, I believe such a terrestrial planet finder is largely an academic pursuit. No wonder there is mention of life-signature searching capabilities in these telescopes, since the masses would be most happy to hear about cosmic neighbours (especially since Mars hasn't proved all that exciting!).
http://efil.blogspot.com/
Finding another planet relativly nearby might result in an even bigger motivation to get there.....
Remember not so long ago te sound barier was seen as unbreakable....
There have already been planets discovered just tens of lightyears away... They are likely to still exist today.
Jeroen
Secure messaging: http://quickmsg.vreeken.net/
Check out the ESO's Overwhelmingly Large Telescope .. 100 meter diameter .. resolution of 1 milliarcsecond .. should be able to image the Lunar Lander on the moon when it's built.
http://www.eso.org/projects/owl/
-Johan
A few years back I (and I'm sure others have done the same) imagined an array of telescopes orbiting the sun in each of the Earth's Lagrangian points synchronized with extremely precise atomic clocks. Wouldn't a 2 AU array allow far better resolution?
I hate Grammar Nazi's
Could someone explain the difference between interferometry on the ground and in space? I thought that it was used to filter out atmospheric interference in ground-based telescopes?
:-)
Is space based interferometry used to filter out things like dust cloud and gravity distortion?
The thought of a huge solar system sized array of telescopes is most excellent
----- Documentation is worth it just to be able to answer all your mail with 'RTFM' - Alan Cox.
It's not an earth size planet - but this is prettty cool. BBC News - link "The historic first image of a planet circling another star may have been taken by the Hubble Space Telescope."
-T
But if you have a self-sustaining colony in space, why even go to a planet? The difference between 66 days and 660 years is that after a few dozen generations, the inhabitants will probably either forget their original mission or chalk it up to "some old religion." Orson Scott Card addressed this "generation ship" issue in more detail in How to Write Science Fiction and Fantasy.
From what little I understand of interferometry and the planet finder, the most difficult task is stabalizing the formation of telescope satellites. Once that can be done reliably, is it possible to add new satellites after the initial formation has been put in place? It seems reasonable to me that you could upgrade the telescope 5 years after launch by sending up another array of satellites that would combine their efforts with the initial group.
Is that something we could expect during the life of the planet finder, or would it be too costly to build that sort of expansibility into the initial system? (If it is possible to expand the interferometer then NASA and ESA could combine efforts by simply designing compatibility and launching on their own schedules. Since I don't know if it's possible, I can't suggest this as a good solution.)
Score one for a Robert L. Forward fan. Not the best in plot and character development but nifty science.
I actually doubt that the Forward scheme for sail decelleration will be used. The problem is that you need an array with an aperture size large enough to hit the primary sail at destination range, instead of just 1 LY or so (distance at the end of the boost phase). This makes it a lot more expensive to build.
You also end up having to use a truly huge primary sail (so that it can focus on the secondary sail at about 1 LY range at the end of the decelleration phase), and keep it perfectly aligned optically during decelleration.
A maser-driven craft with an active-antenna mesh that could do phase-shifting as the primary sail might be able to do this, but primary sail size and maser array size become prohibitive.
Fast-flyby probes are much easier to construct and boost, so I think they're more likely to be implemented if a sail scheme is used at all.