HR: 09:30h
AN: SH11B-07 [PDF]
TI: Comparison of Solar Cycles: Mid- and Low-Latitude Solar Wind During the Declining Phase of the Solar
Cycle
AU: * Elliott, H A
EM: helliott@swri.edu
AF: Southwest Research Institute, P.O. Drawer 28510, San Antonio, TX 78228-051 United States
AU: McComas, D J
EM: dmccomas@swri.edu
AF: Southwest Research Institute, P.O. Drawer 28510, San Antonio, TX 78228-051 United States
AB:
Ulysses measurements now span more than the 11-year solar cycle, and the spacecraft has completed nearly two full polar
orbits of the Sun. In 2001, Ulysses was at high latitudes and SWOOPS (Solar Wind Observations Over the Poles of the Sun)
solar wind measurements showed that a mid-sized circumpolar coronal hole had formed in the Northern hemisphere near solar
maximum. Ulysses then moved towards the equator and encountered a recurrent co-rotating interaction region from $70\deg$N
down to $25\deg$N. From $25\deg$N to $20\deg$N SWOOPS observed slow, steady solar wind. Coronal hole maps show that the
Northern hemisphere has maintained a large circumpolar coronal hole with a large extension, while in the Southern hemisphere
a mid-sized coronal hole has formed at mid-latitudes. The latest Ulysses measurements provide an excellent comparison with
the first orbit observations since as in the first orbit Ulysses is crossing the low-latitude region of variability in the
descending phase of the solar cycle.
DE: 2102 Corotating streams
DE: 2164 Solar wind plasma
SC: SPA - Solar and Heliospheric Physics [SH]
MN: 2003 Fall Meeting