Radio 'Ear' on the Universe Being Built

Radio was the first non-optical portion of the electromagnetic spectrum to be explored by astronomers. This article introduces students to this fact, and that radio astronomy was flourishing in the 1950s. This article sets the stage for the further expansion of astronomy into the X-ray and microwave regions of the spectrum, which become quite important in the 1965 and 1993 issues of Cosmic Times.

Radio astronomy had its origins in the early 1930s, when Karl Jansky was investigating the sources of noise in a radiotelephone system at Bell Telephone Labs in New Jersey. He linked the source of the noise to something in the sky, rather than the immediate surroundings. He identified the source to be the center of our Galaxy. Most astronomers took little notice of this discovery. Grote Reber, a radio engineer and amateur astronomer, learned of the discovery in 1933 and built his own radio telescope. By the early 1940s Reber had made detailed maps of the radio sky.

The impetus for the advancement of radio astronomy were the necessities and technological advances from World War II. The necessities included classified work by the British to determine the source of the jamming of British radars - which turned out to be the Sun. New receivers built for the War provided the basis for new radio telescopes after the War. By the early 1950s, Martin Ryle and Antony Hewish had started the Cambridge catalogues ("2C" and "3C") of radio sources. By the mid 1950s, radio astronomy was flourishing.

Jodrell Bank, which is 25 miles south of Manchester, England, was first used for radio astronomy when Bernard Lovell brought surplus WW II radio equipment there in 1945. Jodrell Bank Observatory was expanded in 1952, offering a place to build the Mark I telescope.

The Mark I telescope at Jodrell Bank was completed in 1957, and later became known as the Lovell Telescope, named for the observatory's founder. Shortly after its completion, it tracked the booster rocket that carried Sputnik 1 into orbit. The Lovell Telescope remains the third largest steerable radio telescope in the world.

The Lovell Telescope has been used to track a number of planetary probes. It has been used extensively for astronomy research, including the study of pulsars, star-forming regions, quasars, and gravitational lenses.

In the Cosmic Times article, the "brightest radio emitter ... in the constellation Cassiopeia" is Cassiopeia A, later found to be a supernova remnant. Cassiopeia A is now extensively studied to understand the nature of supernova explosions, formation of chemical elements, and how the remnant interacts with the surrounding interstellar gas.

Other resources

The following web pages have more detailed information:

• Jodrell Bank Centre for Astrophysics - for current research done at Jodrell Bank and other radio observatories run by University of Manchester.
• Lovell Telescope - Wikipedia article
• Jodrell Bank Observatory - Wikipedia article