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Sanjay87
Sep19-08, 12:11 AM
Is a radio telescope less sensitive on the galactic plane? If so, why?

/San

Chronos
Sep19-08, 01:31 AM
A radio telescope is no different than an optical telescope aside from the frequency band observable.

Sanjay87
Sep19-08, 01:37 AM
So in that case, the answer mist be "yes". But why is it less sensitive? I am a newbie, so my question might sound a little strange.

Thanks,
San

Chronos
Sep21-08, 01:15 AM
So in that case, the answer mist be "yes". But why is it less sensitive? I am a newbie, so my question might sound a little strange.

Thanks,
San
Mostly wavelength. You have less resolution with longer wavelengths. Radio waves are huge compared to optical wavelengths.

Utwig
Sep21-08, 03:46 PM
Hi

Many things affect the sensitivity of radio receivers, either radio telescope, RADAR or just plain old radio. The biggest culprit is usually noise as this can have a very large impact on what you are trying to receive. It does follow that if you are looking into a field where there are lots of noise sources its going to be harder to define and filter out only the part you are interested in, and in some cases more sensitive receivers are even more adversely affected simply because they pick up too much junk along with the desired signal.

I guess if you are on the plane, looking towards the centre, then you have the most potential for undesired noise sources, a bit like trying to have a conversation in a loud night club, you can still do it, its just a lot harder than trying to have a conversation in a quiet room for example.

Hope this helps.

Utwig

Chronos
Sep23-08, 01:19 AM
Optical mirror are figure to fractions of a wavelength [nanometers]. Radio telescope dishes are figured to about a quarter inch.