22 Jan /15

Radio Frequency

The term radio frequency is another centenarian to join our list of words celebrating 100 years this year. It was first printed in English in The Electrician, a British scientific journal, which stated: “Mercury arc rectifiers can be operated at a good efficiency even at radio frequencies”. After reading this sentence, the term may not ignite your curiosity initially, but in the context of radio astronomy, radio frequency starts to become a more intriguing and mysterious scientific phenomenon.

Radio waves are part of the electromagnetic spectrum and oscillate at a very high frequency of 300 GHz to a very low frequency of 3kHz; this is what we understand as radio frequency. In the field of radio astronomy, scientists use radio frequency to study activity in space. At a radio frequency of about 15 MHz up to 38 MHz, scientists can hear noise produced by interaction between Jupiter and its moon, Io. Solar bursts can also be heard, as well as many other sounds originating from cosmic objects.

Depending on how much of a space geek you are, perhaps the most fascinating discovery to be derived from the use of radio frequency is the Wow! Signal

SETI stands for Search for Extraterrestrial Intelligence and for decades the SETI Institute, as well as other universities and organizations, have carried out SETI projects, scanning the skies for signs of life beyond earth. In 1977, using the Big Ear radio telescope at the Ohio State University Radio Observatory, the American astronomer Jerry R. Ehman made history when he recorded a signal of unknown origin in space. He was so amazed at what had appeared on his computer print out that he circled the signal and wrote a big Wow! in red pen, thus naming this mysterious signal. Whether the signal Ehman recorded was really a sign from space is the source of debate, yet to this day it remains unexplained and it is the only time a cosmic signal of unknown origin has ever been recorded.

So there you have it…you may think you understand the term radio frequency, but now you know a little more about the incredible insight it gives us into our universe. One day, by using radio frequency, we might get another chance to hear from life beyond the stars.