Fine structure in the Magellanic Stream

Dr Erkes and I, of Dudley Observatory, and Dr Ken Turner, of the Carnegie Institution of Washington, used the 300 foot radio telescope at the National Radio Astronomical Observatory, Greenbank, West Virginia in March of 1977 to measure neutral hydrogen at 21 cm in three 2° strips across positions indicated by Mathewson, Cleary, and Murray (1974, Astrophys. J., 190, 291) as being part of the Magellanic Stream. in region “A” (centred at α = 22h44m, δ = +24 0.5) no hydrogen was found above the background (3 × 1019 H atoms cm−2). in a revised map Mathewson and Schwarz (1976, Mon. Not. R. astr. Soc., 176, 47P) show that this region is not occupied by the stream. in regions “B” and “C” (centred at α = 23h10m, δ = +11° and α = 0h00m, δ = −17°) hydrogen was detected at the velocities found by Mathewson and Schwarz. Maps of the structure found in these regions are shown in Figure 1.