The Wow! signal was a transmission detected by the SETI Professor Jerry Ehman in August 1977 while working on a radio telescope in Ohio state. Professor Ehman was so excited, he wrote "wow" in the margins of the print-out on which he detected the transmission. The signal itself was thirty times stronger than galactic background noise. It was transmitted and received on the twenty-one centimeter frequency, which no satellite transmitters were allowed to use.