On Wed, Mar 16, 2011 at 1:14 AM, Hal Murray <[email protected]> wrote:
> Your pointing accuracy is Y/X, or something close to that. That describes perfectly when radio can beat optics. The angular resolution of the system is the aperture size over the wavelength. So you can see that a radio telescope must be on other 1000 times wider then an optical telescope if both are to have the same resolution. On an amateur budget optics wins because while one can afford a 12" diameter optical telescope a 1000 foot baseline antenna array will not fit in the typical back yard. optical scopes have a limited maximum size. Currently this as roughly about 10 meters in diameter but technology exists to build a radio antenna array that is one Earth diameter wide. So radio wins if you have a government or university sized budget But optics is catching up and there are now wide optical arrays but the technology to combine light from multiple scopes in phase is expensive and depends on precision mechanical devices, long tunnels and so on. The Charra Array here in LA on Mt. Wilson was designed with the goal of imaging flares and spots on stars. There have been proposals to fly a wide baseline optical system in space, such a system could in theory see continents and oceans on planets around other stars but realistically the technology is not yet there. so that will have to wait for the 2nd half of this century. -- ===== Chris Albertson Redondo Beach, California _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
