2015IOAA理论短问题第4题-观测黑洞

英文题目

Let us assume that an observer using a hypothetical, far-infrared, Earth-sized telescope (wavelength range 20 to 640 $$\mu m$$) found a static and neutral supermassive black hole with a mass of $$2.1 \times 10^{10} M_{\odot}$$. Determine the maximum distance at which this black hole can be resolved by the observer.