OBSERVATIONS OF EVOLVING TURBULENCE IN THE POLAR SOLAR-WIND

The Ulysses magnetic field experiment has measured the heliospheric ma gnetic field in solar wind flows from the Sun's Southern polar coronal hole over a wide range of heliolatitudes and distances. We present an analysis of more than one year of data, covering a latitude range of 40 degrees to 80 degrees S and a distance range of 4.0 to 1.7 AU. We e xtend an earlier analysis of Ulysses magnetic field data and, by calcu lating structure functions, demonstrate that the spectrum of fluctuati ons in the magnetic field changed along the orbit of Ulysses within po lar flows and that this change is a result of the variation in Ulysses ' distance from the Sun, rather than its latitude. We interpret this c hange as being due to the development of turbulence in the polar solar wind.