Question

Suppose your Newtonian reflect has an objective mirror 10 cm (4 inches) in diameter.

a) What is the telescope's diffraction-limited angular resolution when used with yellow light of wavelength 600 nm?

b) A binary star is a system of two stars orbiting each other. Suppose you are observing a binary star consisting of two yellow stars having an angular separation of 0.5 arc-seconds. Will your telescope be able to resolve the two stars? Explain your answer.

c) Would you be able to resolve the two stars of this binary star system if you instead used the Hubble Space Telescope (diameter 2.4 m)? Justify your answer.

Answer 1

diamter of the mirror = D-10 cm The Rayleigh criterion for the minimum resolvable angle by telescope of objective diamter D 0 1.22 angular resolution A-wave length of light -600x10 m D- diameter of telescope objective mirror -10cm after substituting the values in the relation 0-7.320e - 06 rad b) The distance be tween twostars is-S distance from earth to stars r 0---0.5arc sec 2.4241e - 6rad the angular seperation < the diffraction limited angular resolution hence, the telescope would not be able to resolve the two star:s. c) Hubble Space Telescope diameter - D-2.4 m The Rayleigh criterion for the minimum resolvable angle by telescope of objective diamter D 0-1.223.050e-07 rad since the angular seperation (2.4241c -6 rad) between stars the diffraction limited angular resolution (3.050c-07 rad) hence, the hubble telescope would be able to resolve the two stars