Dear Sir:
While there have been some actual transmissions from Earth to the Solar System seeking echos, and some of this might still be going on in a coordinated fashion, as I understand it, the primary mission of the existing radio telescopes is to "Listen" to upper wavelength radio emissions from gas clouds, and other phenomina in the universe. Of course, once some interesting
radio emissions are detected, a full spectrum scan of the target is most likely conducted to determine the full extent of radio
signals from that source.
Other radio transmissions are made from Earth to our traveling Space Probes and Robotic Explorers at various locations in the Universe. A continual litany of telemetry, television and voice signals also flows between the Space Station and Ground Control Center to keep a constant watch on the health, status, and activities of the space crew, mission, and the station itself.
I will defer to someone from one of those positions for an
answer as to the power and frequency of transmissions from Earth to the Space Station, Earth to the Robot Explorers, and Earth to the existing Space Probes way out in deep space.
My guess is that these various transmissions take place on frequencies between 2,500 Mhz and 40,000 Mhz. That is a
very large radio spectrum.
Since my response turns around your question, in that I am telling you that the biggest radio telescopes listen rather than
transmit, let me also tell you that the biggest radio telescopes are not simply single structures at a given location. In recent years a scheme for the linkage of two or more radio telescopes was developed. Therefor, the biggest radio telescope would be an electronic combination of the signals from most of the largest installations on Earth. A lot of work has been done in that vein in recent years. Using more than one receiving antenna provides an easy means for researchers to filter out local ground (earthbound) noise generators and radio disturbances. Signals heard at the same time by widely separated receiving antennas (and equipment) are most probably from the sighted target source (assuming both antennas are aimed at the same target). It is also interesting to know that the radio signals that are received require a vast amount of processing to be identified and detected. The processing of the radio telescope incoming signals takes a huge array of computers and some very complex software programs to yield useable data.
Yes, radio waves do go on forever. However, their strength at the point of interception decreases by the square of the distance from the source. So, the strength of radio waves become very, very weak as you move into distances like 100,000,000 miles.
The wave front would continue out like rings of water in a pond until they hit something and bounced back off of it. In that sense,
a portion of the radio wave would not go on forever, but would become a new wave moving in the oposite direction from the new source (which was the object that the wave struck). The
rest of the wave front would continue on until it struck something, and we repeated the above scenario. The exact same thing happens to signals transmitted from a sonar transducer in the water. Those devices are used to detect the depth of the bottom of rivers/oceans (depth finder), fish in the water (fish finder), or even other vessels (sub hunting). Sonar, uses sound waves and not radio waves, but the principle is almost the same. Sound waves radiate out. Nearby echos are strong enough to be detected with existing equipment and are plotted and displayed on information screens. Some echos are so weak coming back that the existing equipment cannot detect/plot/or display them.
Regards,
Zah
2006-11-19 05:16:22
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answer #1
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answered by zahbudar 6
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Yes, technically, but due to the inverse-square law, it will get weaker and weaker until it is no longer detectable. Look at how faint the stars are, and up close to them they are suns just like our sun!
We could use a laser, which is not subject to the inverse-square law because they are coherent light, because the mirrors in theoptical cavity are almost perfectly parallel. But even a laser is not perfect, because the mirrors are only as perfect as we can make them. So even a laser would spread out a little, and become weaker, just not as fast as the signal from an antenna (which we call a 'point-source'.)
In addition to this, there is gas, dust, and other radiations our there in space which can interfere with any signals we might produce.
It is probably a good thing this happens. If there are other people out there, we don't want them getting the impression that we are like the Simpsons.
19 NOV 06, 1823 hrs, GMT.
2006-11-19 05:19:41
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answer #2
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answered by cdf-rom 7
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Radio waves, just like light waves, would theoretically radiate out into space forever if unimpeded. Broadcasts of high intensity rap music have been known to destroy planets as far away as Plutox Beta in the Horse Head Nebula.
2006-11-19 04:15:42
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answer #3
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answered by Wallster 2
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Q.1. Ratan-600 Telescope in Russia:576 meters across.
Q.2.Yes. Like any electromagnetic impulse it would vary inversely as the square of the distance. As long as it had ANY energy to begin with, its energy content would never fall to zero, although it might (and would) become immeasurably small.
2006-11-19 06:48:57
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answer #4
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answered by JIMBO 4
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specific. besides the undeniable fact that, there are just some places (even in area) the place there is truthfully not something affecting the ball. in case you have been on the area station (working example) and, for the duration of an area walk, threw the ball in a similar direction simply by fact the station's orbit, the ball could be on an orbit that's ever so somewhat greater than the station. regardless of an quite stable throwing arm, you may throw the ball at basically a hundred mph (that's around 0.044 km/s). The station orbits at variety of 17,000 mph. to flee Earth's gravity, the ball could elect to realize a minimum of 24,000 mph (even somewhat greater beneficial than that). So your ball continues to be in orbit around the Earth. on the station's "altitude", there are nonetheless molecules of air. The ball could at last decelerate (not very rapid, yet nonetheless) and finally its orbit could decay. The station itself has that difficulty and could be boosted lower back up each now and lower back. Even greater beneficial out, there is the gravity from the sunlight. there is likewise the "photograph voltaic wind" of charged debris, the rigidity of the sunlight's easy... outdoors the photograph voltaic equipment, there may be the cosmic rays from the Galaxy... that's by no skill relatively empty available.
2016-10-22 08:55:35
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answer #5
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answered by ? 4
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An object in motion will stay in motion untill acted upon by an outside force. The radio wave will theoreticaly never stop until it comes in contact with another object.
2006-11-19 05:07:49
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answer #6
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answered by Elite 3
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Yes, it goes on forever, because there is nothing in space to stop it. It does however DISSIPATE, i.e. the signal gets spread out until it is almost undetectable, but still there thanks to Newton
2006-11-19 04:04:50
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answer #7
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answered by ? 2
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