- #1
joker_900
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Homework Statement
An earth-based telescope with a mirror of diameter 2.4 m can record the im-
age of a faint star in 1 hour. A telescope placed in space (above the atmosphere)
has a mirror of the same focal length as that of the earth-based instrument, but
its diameter is 1.2 m. Atmospheric turbulence is assumed to place a limit of 0.25
seconds of arc on the angular resolution obtainable by earth-bound telescopes,
and the mean wavelength of the radiation detected is 550 nm. Estimate the
time required by the telescope placed in space to record the same star.
Homework Equations
f no. = focal length/aperture diameter
The Attempt at a Solution
The only thing I can think of is to calculate the f no. (focal length/mirror diameter) for each and say this is proportional to the time (as it is a measure of brightness, and so flux, and the greater the flux the shorter the time). However this would ignore any atmospheric effect of reducing flux.
There is another part to the question, so this part might not need all the information provided.
Thanks