![]() |
What is the highest radio frequency used for astronomy? Is it 3,438 GHz?
Hi:
What is the highest radio frequency used for astronomy? Is it 3,438 GHz? According to the link below, it is 3,438 GHz: http://books.nap.edu/openbook.php?re...=11719&page=11 Is 3,438 GHz the highest radio frequency used for astronomy? Thanks, Radium |
What is the highest radio frequency used for astronomy? Is it 3,438 GHz?
"Radium" wrote in message ps.com... Hi: What is the highest radio frequency used for astronomy? Is it 3,438 GHz? According to the link below, it is 3,438 GHz: http://books.nap.edu/openbook.php?re...=11719&page=11 Is 3,438 GHz the highest radio frequency used for astronomy? Thanks, Radium Radium As the article suggests, higher frequencies are considered as being in the infra red wavelengths of light, so 3,438 GHz can be considered to be at the upper limits of radio frequency astronomy. Visible light, ultra violet light, x-rays and gamma rays are all electromagnetic waves at higher frequencies and are also used for astronomy observations and experiments. Satellites are generally used to observe in the ultra violet, x-ray and gamma ray spectrums as these wave lengths are largely absorbed by the earth's atmosphere. Remember, there are no strict cut off frequencies where one type of electromagnetic wave becomes another type. Radio merges into infra red which merges into visible light, ultra violet, x-rays and so on. Any limits are purely arbitary ones applied by humans in order to categorise the way in which electromagnetic waves of a certain frequency can be expected to behave. Look at a colour palette. It is easy to pick out the primary colours. Everyone who isn't colour blind can pick out red, blue, green, yellow etc. But where do you draw the line to decide where red becomes green, blue or yellow? The colours slowly merge from one to another just as the characteristics of radio waves change as frequency increases. Mike G0ULI |
What is the highest radio frequency used for astronomy? Is it 3,438 GHz?
What is the highest radio frequency used for astronomy? Is it 3,438
GHz? According to the link below, it is 3,438 GHz: http://books.nap.edu/openbook.php?re...=11719&page=11 Is 3,438 GHz the highest radio frequency used for astronomy? That's very much a matter of convention. It all depends what you choose to call "radio frequency" and what you choose to call something else. As the article you cite points out, the measurements at 3438 GHz (3.438 THz) blur the lines between microwave measurements (which many would call "radio") and far-infrared measurements (which may would not call "radio frequency"). One source I see gives a frequency of 3.0 THz as the boundary between "microwave" and "infrared". That boundary point is, I believe, entirely one of human convention - there's no magical change in the behavior of the signals as you cross from one side of this frequency to the other. If you choose to treat the conventional boundary point of 3.0 THz as being significant for the purpose of your question, then one would have to say that the 3,438 GHz measurements you refer to are *not* "radio frequency" measurements, but rather "far-infrared" measurements. -- Dave Platt AE6EO Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
What is the highest radio frequency used for astronomy? Is it 3,438 GHz?
"Dave Platt" wrote in message ... What is the highest radio frequency used for astronomy? Is it 3,438 GHz? According to the link below, it is 3,438 GHz: http://books.nap.edu/openbook.php?re...=11719&page=11 Is 3,438 GHz the highest radio frequency used for astronomy? That's very much a matter of convention. It all depends what you choose to call "radio frequency" and what you choose to call something else. As the article you cite points out, the measurements at 3438 GHz (3.438 THz) blur the lines between microwave measurements (which many would call "radio") and far-infrared measurements (which may would not call "radio frequency"). One source I see gives a frequency of 3.0 THz as the boundary between "microwave" and "infrared". That boundary point is, I believe, entirely one of human convention - there's no magical change in the behavior of the signals as you cross from one side of this frequency to the other. If you choose to treat the conventional boundary point of 3.0 THz as being significant for the purpose of your question, then one would have to say that the 3,438 GHz measurements you refer to are *not* "radio frequency" measurements, but rather "far-infrared" measurements. -- Dave Platt AE6EO Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! I am curious here. At some point you have to switch from metallic conductors and antennas to lenses and other optics. Any idea what the highest frequency RF amplifier works at? Tam |
What is the highest radio frequency used for astronomy? Is it 3,438 GHz?
On Thu, 30 Aug 2007 14:52:12 -0700, Radium wrote:
Hi: What is the highest radio frequency used for astronomy? Is it 3,438 GHz? According to the link below, it is 3,438 GHz: http://books.nap.edu/openbook.php?re...=11719&page=11 Is 3,438 GHz the highest radio frequency used for astronomy? No. Hope This Helps! Rich |
What is the highest radio frequency used for astronomy? Is it 3,438 GHz?
In article ,
Tam/WB2TT wrote: I am curious here. At some point you have to switch from metallic conductors and antennas to lenses and other optics. Any idea what the highest frequency RF amplifier works at? Dunno about an RF amplifier per se. I do know that there have been some very interesting experiments with nanotechnology, over the past couple of years, in which tiny carbon nanotubes have been used as optical-frequency antennas. http://www.nanowerk.com/spotlight/spotid=1442.php has a brief writeup on one such. -- Dave Platt AE6EO Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
What is the highest radio frequency used for astronomy? Is it3,438 GHz?
Tam/WB2TT wrote:
"Dave Platt" wrote in message ... What is the highest radio frequency used for astronomy? Is it 3,438 GHz? According to the link below, it is 3,438 GHz: http://books.nap.edu/openbook.php?re...=11719&page=11 Is 3,438 GHz the highest radio frequency used for astronomy? That's very much a matter of convention. It all depends what you choose to call "radio frequency" and what you choose to call something else. As the article you cite points out, the measurements at 3438 GHz (3.438 THz) blur the lines between microwave measurements (which many would call "radio") and far-infrared measurements (which may would not call "radio frequency"). One source I see gives a frequency of 3.0 THz as the boundary between "microwave" and "infrared". That boundary point is, I believe, entirely one of human convention - there's no magical change in the behavior of the signals as you cross from one side of this frequency to the other. If you choose to treat the conventional boundary point of 3.0 THz as being significant for the purpose of your question, then one would have to say that the 3,438 GHz measurements you refer to are *not* "radio frequency" measurements, but rather "far-infrared" measurements. -- Dave Platt AE6EO Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! I am curious here. At some point you have to switch from metallic conductors and antennas to lenses and other optics. Any idea what the highest frequency RF amplifier works at? Tam I have even seen optics and electronics combined in an experimental Road radar for car control from Philips, radar output was a very small horn antenna connected to a wave guide, and in front of that they used a plexyglass condensor lens to make a narrow beam, like you do with light. Apparently those mm waves liked that plastic lens just fine. |
What is the highest radio frequency used for astronomy? Is it3,438 GHz?
In article ,
Sjouke Burry wrote: I have even seen optics and electronics combined in an experimental Road radar for car control from Philips, radar output was a very small horn antenna connected to a wave guide, and in front of that they used a plexyglass condensor lens to make a narrow beam, like you do with light. Apparently those mm waves liked that plastic lens just fine. It's also possible to use photonic crystals and quasicrystals to refract and band-process electromagnetic energy across a very wide range of frequencies... all the way from radio, through microwave, through far infrared, and into the optical spectrum. -- Dave Platt AE6EO Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
What is the highest radio frequency used for astronomy? Is it3,438 GHz?
Dave Platt wrote:
... I do know that there have been some very interesting experiments with nanotechnology, over the past couple of years, in which tiny carbon nanotubes have been used as optical-frequency antennas. http://www.nanowerk.com/spotlight/spotid=1442.php has a brief writeup on one such. Let's hope, super cheap, super efficient solar panels would be great! Bye, bye power company ... Regards, JS |
All times are GMT +1. The time now is 03:53 PM. |
Powered by vBulletin® Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
RadioBanter.com