USAAAO — 2022 First Round

The resolution of a space telescope is theoretically limited by diffraction from its primary mirror. In this problem, we will compare the diffraction limit of the Hubble Space Telescope (HST) (primary mirror diameter d = 2.4 m) and the James Webb Space Telescope (JWST) (d = 6.5 m). The operating wavelengths for the two telescopes are 500 nm and 10 µm respectively. Calculate the ratio of the diffraction-limited angular resolution θ(HST)/θ(JWST). Which telescope can resolve smaller angular features if limited only by diffraction?