Bertucci César L
Space and Atmospheric Physics Group, Imperial College London, London SW7 2BZ, UK.
Philos Trans A Math Phys Eng Sci. 2009 Feb 28;367(1889):789-98. doi: 10.1098/rsta.2008.0250.
The structure and variability of Saturn's magnetic field in the vicinity of Titan's orbit is studied. In the dawn magnetosphere, the magnetic field presents a significant radial component directed towards Saturn, suggesting that Titan is usually located below the planet's warped and dynamic magnetodisc. Also, a non-negligible component along the co-rotation direction suggests that Saturn's magnetic field lines close to the magnetodisc are being swept back from their respective magnetic meridians. In the noon sector, Titan seems to be closer to the magnetodisc central current sheet, as the field lines in this region seem to be more dipolar. The distance between the central current sheet and Titan depends mainly on the solar wind pressure. Also, delta|B|/|B| approximately 0.5 amplitude waveforms at periods close to Saturn's kilometric radiation period are present in the background magnetic field. This modulation in the field is ubiquitous in Saturn's magnetosphere and associated with the presence of a rotating asymmetry in the planet's magnetic field.
对土卫六轨道附近土星磁场的结构和变化进行了研究。在黎明磁层中,磁场呈现出一个指向土星的显著径向分量,这表明土卫六通常位于行星扭曲且动态的磁盘下方。此外,沿共转方向的一个不可忽略的分量表明,靠近磁盘的土星磁场线正从各自的磁子午线被向后扫。在午间扇区,土卫六似乎更靠近磁盘中心电流片,因为该区域的场线似乎更具偶极性。中心电流片与土卫六之间的距离主要取决于太阳风压力。此外,在背景磁场中存在周期接近土星千米波辐射周期的约0.5幅度波形的Δ|B|/|B|。这种磁场调制在土星磁层中无处不在,并且与行星磁场中旋转不对称的存在有关。