For many years astronomers have mused about the possibility of putting radio telescopes on the Moon. Considering the extreme temperature variations, high levels of solar radiation (our atmosphere protects us), fine abrasive dust that gets into everything, and of course the logistical difficulties, why would we want to do that?

Radio astronomy is the study of naturally occurring radio emissions from space. Despite the enormous power radiated by most cosmic radio sources, their huge distances from us mean that by the time these radio emissions reach us they are incredibly weak.

If an optimistic astronaut was standing on the lunar surface trying to use his or her cell phone, the signal reaching us here on Earth would be stronger than the signals reaching us from any of those cosmic radio sources, possibly other than the Sun when it is particularly active. Since all the cell phones operating around us are a lot closer than the Moon, we have to protect our radio telescopes from them, and also from........

© Castanet