Recent Ulysses Fast latitude Scan: Magnetic Field Observations
Abstract
In January 2006, the Ulysses spacecraft passed completely above the Heliospheric Current Sheet (HCS) at latitude -37 degrees and entered the fast wind. It reached maximum southern latitude of - 80 degrees in February 2007. Continuous field measurements provide a second opportunity to investigate the 3D heliosphere at solar minimum under significantly changed circumstances, a reversal in the magnetic field polarity and a polar cap field smaller by a factor of about 2. As in 1994-1995, observations of r2 Br are independent of latitude. However, the average value appears to have decreased with a marked change in the non-Gaussian probability distribution functions indicating a systematic change in the large amplitude magnetic fluctuations. February 2007 began the Fast Latitude Scan (FLS) when Ulysses sweeps between polar caps in only 10 months reducing the influence of temporal variations. This interval is also optimal for investigating north-south asymmetries. Ulysses traveled northward leaving high- speed high-latitude wind and crossing the HCS at -30 degrees. In August, Ulysses crossed the ecliptic plane at nearly the same longitude as Earth and the network of near-Earth spacecraft. The FLS ends in November. These new magnetic field observations will be presented and compared with those at the previous solar minimum.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2007
- Bibcode:
- 2007AGUFMSH14A1701S
- Keywords:
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- 2134 Interplanetary magnetic fields;
- 2149 MHD waves and turbulence (2752;
- 6050;
- 7836);
- 2162 Solar cycle variations (7536);
- 2169 Solar wind sources