KAISTSAT-4

KAISTSAT-4, the fourth satellite developed by Korea Advanced Institute of Science and Technology, is to be launched into a sun-synchronous orbit at 685 km altitude on September 26, 2003. While the primary objective of the mission is to provide spectral sky survey data of hot Galactic plasmas with Far Ultra-violet Imaging Spectrograph (FIMS, also known as SPEAR), the same instrument observes auroras and airglow with high spatial resolution and detailed spectral information. The FIMS bandwidth, 900 ?1175 A and 1335 ?1750 A, includes important atomic oxygen lines and Lyman-Birge-Hopfield (LBH) emissions that provide information on the precipitated electron energy associated with auroras. This information is compared with simultaneous in-situ measurements of keV electrons on the same spacecraft. It should be noted that previous similar studies require a serendipitous opportunity of two independent spacecraft observing the same region at the same time. A 10 Hz FIMS sampling rate yields images of sub-kilometer spatial resolution which can be used to study the small scale dynamics of auroras. Also, the effects of precipitating electrons on the ionosphere are monitored by two sets of cylindrical Langmuir probes, which are oriented perpendicular to each other. The initial result of KAISTSAT-4 is presented in this paper.