Alexander.J.VanDerHorst@nasa.gov

¹ Space Science Office, NASA/Marshall Space Flight Center, Huntsville, AL 35812, USA.
² Astronomical Institute, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
³ Joint Institute for VLBI in Europe (JIVE), Postbus 2, 7990 AA Dwingeloo, The Netherlands
⁴ MTA Research Group for Physical Geodesy and Geodynamics, H-1585 Budapest, P.O. Box 585, Hungary
⁵ University of Maryland, Department of Astronomy, College Park, MD 20742, USA
⁶ International Centre for Radio Astronomical Research, University of Western Australia, 7 Fairway, Crawley, 6009, Australia
⁷ University of New Mexico, Department of Physics and Astronomy, MSC07 4220, 800 Yale Blvd., NE Albuquerque, NM 87131-0001, USA
⁸ Centre for Astrophysics Research, University of Hertfordshire, College Lane, Hatfield, Herts, AL10 9AB, UK
⁹ Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064, USA
¹⁰ National Centre for Radio Astrophysics, Post Bag 3, Ganeshkind, Pune 411007, India
¹¹ Netherlands Institute for Radio Astronomy (ASTRON), Postbus 2, 7990 AA Dwingeloo, The Netherlands
¹² Kapteyn Astronomical Institute, University of Groningen, Postbus 800, 9700 AV Groningen, The Netherlands
¹³ Department of Physics & Astronomy, University of Leicester, Leicester, LE1 7RH, UK
¹⁴ Inter-University Center for Astronomy and Astrophysics, Pune, Ganeshkhind, Post Bag No. 4, India
¹⁵ Mullard Space Science Laboratory, University College of London, Holmbury St Mary, Dorking, Surrey RH5 6NT, UK
¹⁶ Leiden Observatory, University of Leiden, P.B. 9513, Leiden 2300 RA, The Netherlands
¹⁷ Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia
¹⁸ NASA Postdoctoral Program Fellow.
¹⁹ G.B. Taylor is also an Adjunct Astronomer at the National Radio Astronomy Observatory.