"Peter Webb" wrote in message
...
"Margo Schulter" wrote in message
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In sci.astro.amateur gwatts wrote:
Radium wrote:
Hi:

What is the highest radio frequency used for radio astronomy?

According to the link below, it is 3438 GHz:

http://books.nap.edu/openbook.php?re...=11719&page=11

Is 3438 GHz the highest radio frequency used for radio astronomy?
....
in frequency than the top of the EHF range. While I'm not sure
if there's a specific technical name for this range (analogous
to the various categories of radio waves like EHF), my first
layperson's guess would be that it could be considered very
far infrared (that is, far from the visual spectrum and close
to radio).

http://en.wikipedia.org/wiki/Electromagnetic_spectrum

3.4THz would be well into the far infra-red.

It's interesting question how radio and infrared astronomy are
distinguished: mainly by the nature of the waves, or also by
the apparatus used. I'd like to to learn more of this myself.

Again, I'd emphasize that in giving the range for EHF, I'm not
saying that anything above 300 GHz wouldn't be considered radio,
only mentioning this category as an example of what was
traditionally considered near the top of the radio spectrum.
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So its your contention that the atmosphere is transparent all the way up
from microwaves to IR?

I don't believe Margo suggested that at all. This
page lists some of the sources of line features
in that region:

http://kp12m.as.arizona.edu/docs/wha...millimeter.htm

George