Nature 239, 91 - 93 (08 September 1972); doi:10.1038/239091a0

Occultation of Sgr A

GOPAL KRISHNA, G. SWARUP, N. V. G. SARMA & M. N. JOSHI

Radio Astronomy Centre, Tata Institute of Fundamental Research, Bombay-5

INTERFEROMETRIC^1,2 and lunar occultation³⁻⁵ observations show that the radio source Sgr A, which is located near the galactic centre, consists of several components varying in size from a few arc s to a few arc min. Lunar occultation observations made at Ootacamund on September 9, 1970, have provided detailed information on the structure of the source of 327 MHz and have revealed the presence of an extended component 10 4 arc min in size and centred approximately on Sgr A. The extended source has an inclination of 45° 15° to the galactic plane, similar to that of the 20 cm continuum ridges⁶.

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