Astronomers are looking forward to opening a new window on the universe by posting high-resolution telescopes on the moon, and in orbit around it. There are numerous proposals to do this from astronomers around the world — including one from India called PRATUSH.
On the earth, optical telescopes (which collect visible light at longer wavelengths) and radio telescopes (which collect radio waves with the shortest wavelengths) have to peer through layers of the planet’s atmosphere. While it is becoming increasingly difficult for optical instruments to see through the polluted skies, radio telescopes also contend with radio and TV signals adding to the cacophony of the electromagnetic ‘hiss’ from the communications channels used by radar systems, aircraft, and satellites. It also does not help that the earth’s ionosphere blocks radio waves coming from outer space.
