The Other Telescope
Some of the things being said about this telescope project are it will be able to pick up much weaker signals from ships in space and thus may eventually be the instrument of our contacting alien beings. The Chinese are very interested in making contact as are we and many other nations. One of the reasons we may not have become part of the SKA project is the fact we have something similar in this country. It is called the Very Large Array. There are currently 27 large dishes mounted on tracks which can be moved into different shapes and at different distances. Known as the VLA, each dish has a diameter of 25 meters which is greater than the SKA project telescopes which have a diameter between 12 and 15 meters. The SKA project has about four times as many antennas, which are spread out over a much larger distance which contributes to making the telescope more powerful, but the VLA can have units added to it and I suspect this was why we didn’t join the SKA Project. The history of radio telescopes is interesting. Nikola Tesla thought he had picked up alien communications when working with early radio equipment. Most people who hear the word telescope think of an optical device and never consider the fact we have telescopes which operate not on light but instead use radio waves. In 1932 an engineer at Bell Labs detected radio waves coming from space. He wasn’t looking for this phenomenon. He was trying to find out how to clear up noise in radio transmissions. The first actual radio telescope was built by an amateur in 1937. He did a sky survey which now is routine. To the average person some of the early radio telescopes looked like a pile of metal arranged in odd or box like shapes. Different configurations were used for different frequencies. Using radio telescopes in tandem with optical telescopes have helped produce some discoveries and individual use of each has also produced discoveries. When scientists wanted to get a more accurate idea of the orbit of Mercury, they turned to the radio telescope and found Mercury rotated every 59 days, which was a lot faster than previously thought. An asteroid was discovered by using a radio telescope and for the first time scientists were able to create a 3D picture of it from a radio telescope. We have known for years that stars known as binary pulsars exist, but their existence was first discovered by using a radio telescope in 1983. This was an incredible discovery because these stars rotate about 641 times a second. It is hard to imagine anything spinning that fast. Radio telescopes have even detected molecules in star explosions. Sometimes something which looks very interesting to an astronomer is seen through an optical telescope, but the astronomer may want to see if there is more information about the object he can extract and may enlist a radio telescope to do this. Radio telescopes are sometimes used in interferometry. This is when different receivers are all aimed at the same target and the image is overlayed. This is one way to get more sensitive data out of an observation and will depend on how many arrays operate. Astronomers are able to use just a couple of receivers aimed at a target or the entire array. Now that we have computer control of these telescopes it has made things a lot easier and more precise. Fortunately, electronics seem to also be getting cheaper, allowing for more advance electronics for the radio telescopes. SETI the Search for Extraterrestrial Intelligence has been able to update their radio equipment on a regular basis making their stations that much more powerful every time. One way they are able to do this is by being able to monitor more frequencies. It is important to note when we say radio waves, we are also talking about gamma rays, X-rays, ultraviolet rays and infrared rays among others. Other countries have been conducting radio telescope searches for years besides China and the United States. The Soviet Union had conducted many radio telescope surveys of the skies. The British have quite a few radio telescopes and have what is known as Merlin, which is a group of radio telescopes spread across England and Welsh borders and they work by using interferometry. The current idea is to build mobile units which can work individually, but also using interferometry. The ideal situation is being able to add more units to the array at a later date if needed. This works fine now, but who knows what advances will be made in the future. Humans thought they had the ultimate device when they developed the steam engine for railroad use and kept making it bigger and more powerful until diesel engines came along which were more configurable. You could hook together as many engines as you needed or just use one. We are on the same path right now with radio telescopes.
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