This award will support collaborative research between Dr. Barney Rickett, University of California at San Diego, and Dr. Andrew G. Lyne, Nuffield Radio Astronomy Laboratory, Jodrell Bank, University of Manchester, England. The investigators propose to carry out collaborative observations of interplanetary scintillations of small diameter radio sources. This technique requires three or more radio telescopes at separations of 10 to 200 kilometers, each receiving signals from the same small diameter celestial radio source. The MERLIN antenna system in England is uniquely suitable for such observations. Drs. Rickett and Lyne propose to make measurements from which the speed and direction of the solar wind can be estimated in a range of distances of 10 to 50 solar radii. This region is inaccessible to spacecraft and is of considerable interest in the search for the process that drives the solar wind to expand at supersonic speeds.
