Jansky and the Invisible Universe

The invisible radio universe-you don't see it, you hear it with radio. Faint whispers of radio hiss from deep space. This parallel universe simmers and seethes in an ocean of radio white noise, very much like the noise one hears when a radio is tuned between stations. The image to the left is from the National Radio Astronomy Observatory (NRAO), and is titled "As above, so below". The above is the watery radio sky and the below is a matrix of radio noise sources that are distributed along the plane of our Galaxy, The Milky Way.

One example of a source of radio noise "out there" is the super luminal radio galaxy. A galaxy spins like a giant cosmic hurricane throughout the Universe, hundreds of thousands of light years across, with an inner eye wall and calm eye-the super cooled massive black hole. As worlds of matter get sucked into these black holes some of this matter gets ejected and accelerated to very high speeds out of the center of the galaxy creating highly excited beams of invisible energy millions of light years in length. All this friction creates lots of hissing radio noise, very much like when an electric motor is operated near an AM radio. There are countless billions of these objects in the universe creating a sea of cosmic electromagnetic radio energy and white noise.

The NRAO radio image on the left is of the brightest radio object in the sky-Cygnus A. Lying out at a distance of 700 million light years from Earth and transmitting at 10 to the 38th power in watts, Cygnus A was one of the first objects from deep space that was discovered generating radio noise. The plumes of invisible energy are emitted from the central galaxy, the bright dot in the center of image, and jet out for millions of light years. These regions are radio bright, meaning they create tremendous amounts of electromagnetic energy and radio white noise.

Interest in radio noise became real science in the mid-late 1920's as the newly discovered "short waves" were being used to carry messages in Trans-Atlantic radio circuits.(Figure 1-left) Bell Labs was the leader in this new communication resource and realized that troublesome static could impede the exploitation of this new medium.

These long distance radio circuits were very expensive to build, (Figure 2-right) and Bell Labs was not about to let some radio static rain on their monolithic parade. The first radiotelephone service between New York and London in 1927 was offered at a rate of $75 for a three minute call!

Operators of these early radio circuits were listening on some of the most powerful radio receiving systems ever built. (See Figure 3-left) Along with the ability of these large radio systems to send and receive radio messages across the Atlantic, these receiving systems also picked up tremendous amounts of natural and man made radio noise. Most of the natural radio noise was from QRN-static crashes from local and distant lightning storms. The man-made noise came from many different sources-automobile ignition systems, power lines and street lights, farmer's electric fences, noisy electric motors and appliances, etc. Even with all of this state of the art technology and knowledge, nobody could have imagined that there were also faint whispers of radio hiss from deep space-noise hiding within noise.

In the late 1920's a young radio engineer at Bell Labs named Karl Jansky was given the job of gathering information on shortwave atmospheric radio interference. A main component of this work was a highly directional and rotatable antenna that was come to be known as the merry go round. (See Figure 4-right)This antenna made one complete revolution in 20 minutes and scanned the skies for sources of static.

Jansky's antenna was designed to produce a directive pattern, essentially a radio searchlight. The illustrations below (Figure 5-below left) shows this pattern from a side view and (Figure 6-below right) from an overhead view.

After almost a year and a half of experimenting with this antenna, Jansky mentioned in early 1932 he had noticed three types of static; one from local thunderstorms, one from distant thunderstorms, and "a steady hiss type of static from unknown origin....A very steady continuous interference -the terms 'static' doesn't quite fit it." The economic conditions of the Great Depression were also hitting home at Bell Labs with 4 day work weeks and a 20% reduction in employees. This was also the time that Jansky realized that this radio hiss "always lies in a plane fixed in space." This conclusion was startling, and raised many questions and fears from his superiors about what Jansky had stumbled upon. In 1933 Jansky published a paper entitled "Electrical Disturbances Apparently of Extraterrestrial Origin." This paper is regarded as the most important in astronomy of the 20th century. Jansky's superiors at Bell Labs required that he include the word "Apparently" to his original paper-despite the fact that Jansky was certain it was extraterrestrial in origin. By 1935 Jansky was able show "radiations are received any time the antenna is directed towards the Milky Way system, the greatest response being obtained when the antenna points towards the center of the system." Jansky enjoyed a short lived popularity when the front page of the New York Times announced "New Radio Waves traced to the center of the Milky Way." The figure to the right is a radio image of the center of our galaxy taken in 1999 at the Very Large Array (VLA).

Jansky was a great scientist, explorer, and radio man. He knew he made a major discovery, and did everything he could to convince the powers to be at Bell Labs to pursue this discovery of star static by building a much larger antenna. Unfortunately, Jansky did not have the backing of the scientific and astronomy community of his time, who simply did not understand his work or the significance of his break-through.
Jansky's work with star static was crushed by the bureaucracy at Bell Labs, and Karl's chronic health problems limited his ability to fight for what he believed in.

He died in 1950 at the age of 44, without witnessing the revolution that his work would create.

Fortunately, a young amateur radio operator from Wheaton Il., Grote Reber, W9GFZ, read Jansky's 1937 paper and began to build what would become the world's first radio astronomy dish.

Additional Figures:
The photos in Figures 1,2 and 3 are from "Short-Wave Transatlantic Radio-Telephony"-Bell Labs Record, Printed 1929.