| タイトル | Observations of a Unique Type of ULF Waves by Low-Latitude Space Technology Five Mission |
| 本文（外部サイト） | http://hdl.handle.net/2060/20110015151 |
| 著者（英） | Slavin, J. A.; Le, G.; Chi, P.; Strangeway, R. J. |
| 著者所属（英） | NASA Goddard Space Flight Center |
| 発行日 | 2011-06-27 |
| 言語 | eng |
| 内容記述 | We report a unique type of ULF waves observed by low-altitude Space Technology 5 (ST-5) constellation mission. ST-5 is a three micro-satellite constellation deployed into a 300 x 4500 km, dawn-dusk, and sun synchronous polar orbit with 105.6deg inclination angle. Due to the Earth s rotation and the dipole tilt effect, the spacecraft s dawn-dusk orbit track can reach as low as subauroral latitudes during the course of a day. Whenever the spacecraft traverse across the dayside closed field line region at subauroral latitudes, they frequently observe strong transverse oscillations at 30-200 mHz, or in the Pc 2-3 frequency range. These Pc 2-3 waves appear as wave packets with durations in the order of 5-10 minutes. As the maximum separations of the ST-5 spacecraft are in the order of 10 minutes, the three ST-5 satellites often observe very similar wave packets, implying these wave oscillations occur in a localized region. The coordinated ground-based magnetic observations at the spacecraft footprints, however, do not see waves in the Pc 2-3 band; instead, the waves appear to be the common Pc 4-5 waves associated with field line resonances. We suggest that these unique Pc 2-3 waves seen by ST-5 are in fact the Doppler-shifted Pc 4-5 waves as a result of rapid traverse of the spacecraft across the resonant field lines azimuthally at low altitudes. The observations with the unique spacecraft dawn-disk orbits at proper altitudes and magnetic latitudes reveal the azimuthal characteristics of field-aligned resonances. |
| NASA分類 | Geophysics |
| レポートNO | GSFC.ABS.4676.2011 |
| 権利 | Copyright, Distribution as joint owner in the copyright |
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