GPS Solutions

, 14:91 | Cite as

FORMOSAT-3/COSMIC observations of the ionospheric auroral oval development

  • Ho-Fang Tsai
  • Jann-Yenq Liu
  • Chien-Hung Lin
  • Mei-Lan Hsu
Original Article


The ionospheric radiance and electron density observed by the tiny ionospheric photometer (TIP) and GPS occultation experiment (GOX) payloads on FORMOSAT-3/COSMIC satellites are applied to determine the boundaries of the auroral oval and its width in the winter nighttime ionosphere for both hemispheres. The TIP collects ionospheric emission at 135.6 nm due to electron impact excitation, while the GOX offers ionospheric electron density profiles with radio occultation (RO) technique. Comparison between them shows similar patterns of the plasma structure in the polar caps. The mean width of the auroral bands ranges between about 2 and 11° latitude in the winter nighttime and it varies with longitudes. The comparison by month suggests that the mean radius of the auroral ovals varies with the intensity of the auroral radiance.


FORMOSAT-3 COSMIC Ionospheric auroral oval Auroral radiance Tiny ionospheric photometer GPS occultation experiment 


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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Ho-Fang Tsai
    • 1
  • Jann-Yenq Liu
    • 2
    • 3
  • Chien-Hung Lin
    • 4
    • 5
  • Mei-Lan Hsu
    • 6
    • 7
  1. 1.Taiwan Data Analysis for COSMIC (TACC)Central Weather BureauTaipeiTaiwan
  2. 2.Institute of Space ScienceNational Central UniversityJhong-LiTaiwan
  3. 3.Center for Space and Remote Sensing ResearchNational Central UniversityJhong-LiTaiwan
  4. 4.Institute of Space, Astrophysics and Plasma ScienceNational Cheng Kung UniversityTainanTaiwan
  5. 5.Plasma and Space Science CenterNational Cheng Kung UniversityTainanTaiwan
  6. 6.Earth Dynamic System Research CenterNational Cheng Kung UniversityTainanTaiwan
  7. 7.Department of PhysicsNational Cheng Kung UniversityTainanTaiwan

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