Re: Tomorrow's Monster Telescopes

Quadibloc wrote:
On Mar 9, 1:57 pm, L D'Bonnie <nob...@xxxxxxx> wrote:

Could an instrument be built where it could be said that no more
useful information can be obtained by building larger?

I'm not sure, but I remember once doing a little calculation.

How big would a telescope be, so that a planet, the size of Earth,
orbiting Alpha Centauri, would show as much detail as Mars, viewed
from Earth, using a six-inch telescope?

The answer is - thirty *miles* in diameter. So, I'd say we have a way
to go.

John Savard

Kepler couldn't even begin to dream of supercomputers. As I recall
he he used blocks of wood to do his calculations, then planed them
down so he could use the surface again. What did teraflops mean to
him?

How big could Galileo have built? Something like Hubble was a tad
out of his reach. :)

A telescope thirty miles in diameter? With funding and desire we
could well be in the planning stages of one now.

Seriously though, if you could resolve the disk of a planet at
that distance, could you read a newspaper headline with an instrument
twice that size? Is the only limit to resolution the practical
limits of the size of an instrument?

Mirrors the size of galaxy clusters would be a bit impractical. It
would take thousands of years for the light to come to focus, and
then you would still have to wait a week to get the film back from
the drugstore. (I have yet to buy a DSLR) :)

LdB







.

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