Robert C. Byrd Green Bank Telescope

Without supercooling, radio telescopes struggle to hear* the faint Universe over their own electronic heartbeats. Their receiving equipment must be kept at the lowest temperatures we can manage (hundreds of degrees Fahrenheit below the freezing temperature of water), or all we detect is static and the piercing spikes of man-made radio interference.

http://www.planetary.org/blogs/guest-blogs/2014/0428-gbt-helps-out-an-old-friend.html