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1

I can partially answer this from a pulsar perspective. Across the board, parallax measurements are a fairly new development in radio astronomy. Interferometers are required to attain any reasonable degree in accuracy, and so parallax measurements have come into play mainly in the last two decades, with instruments like the Very Long Baseline Array taking ...


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If you're looking explicitly for radio-loud quasars, I'd recommend looking at a catalog of (mainly extragalactic) radio sources, rather than a catalog of quasars, given that only a small fraction of quasars are radio-loud. The Third Cambridge Catalogue of Radio Sources (VizieR link) might be a nice starting point, particularly given how many objects are ...


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You'd be completely right that a single Fourier transform would be needed if the interferometer were able to sample the entire $(u,v)$ plane. Unfortunately, that's not the case; we only have a fairly small, finite number of dishes and a finite amount of time. Coverage of the plane will increase as time passes and the Earth rotates, but it's going to be ...


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The surface brightness of a source is by definition the flux density per solid angle; the surface brightness sensitivity of a telescope is, analogously, its point source sensitivity divided by the beam solid angle.$^{\dagger}$ Interferometers have smaller beam solid angles than dishes with the same area (Frayer 2017). Given that the solid angle is $\Omega\...


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The precise definition of "homologous" seems to change based on who you talk to. A general umbrella definition is that a homologous radio telescope preserves a particular type of shape as it moves. Unless you can build an unfeasibly rigid dish, gravity will naturally shift the positions of different parts of the dish in different ways, changing the ...


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a "tentative answer". I did not find that the accelerometer was installed this satellite. On the contrary, I found a number of articles on improving the accuracy of the satellite position with mathematical methods. For example string "Ballistic and navigation support for “Spektr-R” spacecraft" for googling. 1/ 1.In russian The paper ...


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