The Society of Amateur Radio Astronomers (SARA)

Why Radio Astronomy?

Because about sixty five percent of our current knowledge of the universe has stemmed from radio astronomy alone. The discovery of quasars, pulsars, black holes, the 3K background from the "Big Bang" and the discovery of biochemical hydrogen/carbon molecules are all the result of professional radio astronomy.

Why AMATEUR radio astronomy?

Large professional radio observatories concentrate on deep sky objects for relatively brief periods of time. It's sort of like looking at the universe through a straw. The amateur, on the other hand, looks at broad areas of sky for long periods of time. Although amateurs can not compete with professional astronomers, we do have some benefits. Modern state of the art low noise receiving equipment now enables amateurs to do viable and useful work. Moreover, the amateur has unlimited time which may be devoted to a single observational project.

How do amateurs do radio astronomy?

Radio astronomy may be conducted using either imaging or non-imaging techniques. Non-imaging radio astronomy includes the observation of radio noises from Jupiter, collection of solar flare data, and meteor infall counts. Non-imaging radio astronomy is conducted with very low cost receiving equipment and relatively simple antenna systems. It usually involves modified communications type receivers which receive a narrow band of radio frequencies.

Imaging radio astronomy involves antennas of rather large size, requires radio quiet locations and broadband receiving equipment. The reason for using the broadband equipment is that discrete radio objects radiate over a large spectrum, therefore a greater receiver bandwidth increases the amount of energy received from the object.

What are amateurs actually looking for in the received data?

The aim of the radio amateur is to find something new and unusual. Just as an amateur optical observer hopes to notice a supernova or a new comet, so does an amateur radio observer hope to notice a new radio source, or one whose radiation has changed appreciably.

What is the purpose in all of this observational activity?

The purpose is the same as for any other scientific investigation. That is, to examine the universe, make any discovery possible and let your work be known. This is accomplished by patient, methodical data taking, careful analysis without personal bias, and the publication of the result. For amateur radio astronomers, the SARA Journal is one medium for publication.

What does the average amateur radio telescope consist of?

In general, the amateur radio telescope consists of a good antenna system, a sensitive, stable, low noise receiver, and various output devices. The output may take the form of a strip chart recorder, a voltmeter or a data logging computer.