USAAAO — 2021 First Round

Where and when should we place a radio telescope such that, when combined with a radio telescope on Earth, the system could "see" the supermassive black hole in Sculptor’s Galaxy (NGC 253)? Sculptor’s Galaxy’s supermassive black hole’s mass is estimated to be around 5 × 10^6 M☉, and its distance is estimated to be around 3.5 Mpc. Out of the options below, pick the one closest to the estimate you obtain, rounding up. Consider the energy of a radio wave to be around 10^-5 eV. Use the following formula to estimate the angular resolution: θ = λ/D.