Astronomers have discovered a planetary system orbiting a star, which is at a distance of 5.0 1018 m from the earth. One planet is believed to be...

Astronomers have discovered a planetary system orbiting a star, which is at a distance of 5.0 × 1018 m from the earth. One planet is believed to be located at a distance of 1.9 × 1011 m from the star. Using visible light with a vacuum wavelength of 551 nm, what is the minimum necessary aperture diameter that a telescope must have so that it can resolve the planet and the star?