Radiowave Scattering and Ultra-long-baseline Interferometry
نویسنده
چکیده
Interstellar scattering can irretrievably blur the images of compact radio sources when examined with extremely high resolution. Because of this effect, diffraction-limited observations of extragalactic sources with a n Earth-Moon baseline will only be possible a t frequencies above about 7 GHz, in which case the resolution will be 5 2 0 parcsec. Preliminary observations to determine the potential usefulness of such resolving power are discussed. The simplest of these would consist of a search for interstellar scintillations in compact sources at 10 GHz, which would provide an effective resolution about equal to that of an Earth-Moon baseline a t this frequency. Also important in this context is the development of very-long-baseline interferometry (VLBI) in near-Earth orbit, as any ultra-high-resolution observations (such as with an Earth-Moon baseline), if appropriate, would require intermediate baselines for mapping.
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تاریخ انتشار 2003