How far away would we be able to detect habitable planets in, say, 2150?

[seawasp]

And at what distance are we going to get details on them? From what I've seen with our progress in remote imaging, it seems to me that in a hundred to a hundred and fifty years (assuming we don't experience a technological collapse of DOOOOOOOM) we'll be well able to get pictures of planets with continental detail in other solar systems. But I don't have a good idea of how distant those solar systems could be; I'm sure we could (if they existed) get pictures of fair-sized islands on a planet around Alpha Centauri by that time period, but what about something 10 LY away? 50? 100? How far away will something have to be for us to know only roughly "there are planets there, and we think there's an oxygen atmosphere around this one, but we've got few other details."?

Comments

[howardtayler.livejournal.com]

The challenge lies not in the optics, but in the software to filter out the parent starlight. I'm sure that within 150 years we'll have telescopic arrays in solar orbit, allowing us to create HUGE virtual lenses. If there's a planetary body reflecting starlight, we'll be able to capture that light.

But we'll then need to figure out how to remove the millions-of-times-brighter light from the parent star. We can already do pretty impressive things to clean noise out of audio and video... I expect that our abilities 150 years from now will approach the limitations of the medium.

[gary-jordan.livejournal.com]

I truly wish I could predict that the detail on Alpha-Centurian planet pictures would be from the Hubble above the colony there.

[scott-sanford.livejournal.com]

To a great degree this is not a question of engineering but of funding. How much astronomy can be done on the existing grant money? Someone will eventually ask, "Okay, so you've mapped continents on planets fifty lightyears away that we can't get to; who cares about mapping planets five hundred lightyears away?"

I'd say the author is free to pull out whatever numbers suit the story.

[eddy-b.livejournal.com]

The most important data is spectrographic. Detection of an Oxygen atmosphere is more important than continental pictures.

[izeinwinter.livejournal.com]

Well, assuming both happens, getting the gravitic lens telescope pointed at something is going to be a bit of a hassle - the damn thing will have to hover in a forced orbit at all times, and retargeting it on something even ten degrees away from its current target will mean flying a fairly mindblowing distance. So, very, very good images of the most interesting targets - and any planet that is known to have an oxygen line would certainly qualify - but for anything new, it has to make it to the top of the priority queue first.