Early VLBI in the USSR

Abstract

This article gives story of interferometer with independent elements (Very Long Baseline Interferometer) in Russia. At the end of February 1962 the author discussed with G.Ya. Gus'kov, DSN Station, Evpatorija a new type of radio interferometer and proposed an experiment between two DSN stations. In September 1962 he reported the new method and proposed a VLBI experiment at seminar of Radio Astronomical Laboratory, Pushino, and then at a seminar of Astronomical Institute GAISH which recommended to take out a Patent. In December GAISH sent documents to the Patent Bureau. In summer 1963 the author discussed with B. Lovell in Evpatorija the VLBI method of and we signed memorandum an Ev‐JB experiment at λ = 32 cm. In December 1963 the Patent Bureau permitted publication, and the paper was sent to Radiofizika. Really VLBI in the USSR began with the proposal of M. Cohen and K. Kellermann, February 1968, to do an experiment between 22‐m antenna Pushino and 43‐m Green Bank. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Early VLBI in the USSR

“…Shklovskii to support the astrophysical part and G.S. Khromov for translation [2]. I acquainted Prof. B. Lovell with the technical part, including transmitter, atomic standards, low-noise receivers, and radio astronomical studies.…”

“…K. Kellermann asked Olof Rydbeck to send working rubidium standard. After a few days interferometer fringes at 6 cm were detected [2,9]. …”

“…The main problem was local oscillator stability. We decided to begin testing equipment on the short baseline within the USA, and then move to intercontinental baselines [2].…”

“…The apogee of 20,000 km was determined by the high-energy particles and non-uniform gravity field of the Earth, the perigee of 70,000 km by the space radio telescope sensitivity. The project had a broad international cooperation, which included the USA, Australia, India, and European countries [2,28]. One of a Soviet-FRG work meeting had been in Moscow.…”

“…Compact radio sources were needed for calibration. The candidates were sources of relativistic particles, like the Crab Nebula that ejected relativistic jets [2]. These sources were suspected to be variable in radio emission.…”