The transition region and coronal explorer

The Transition Region and Coronal Explorer (TRACE) satellite, launched 2 Ap ril 1998, is a NASA Small Explorer (SMEX) that images the solar photosphere , transition region and corona with unprecedented spatial resolution and te mporal continuity. To provide continuous coverage of solar phenomena, TRACE is located in a sun-synchronous polar orbit. The similar to 700 Mbytes of data which are collected daily are made available for unrestricted use with in a few days of observation. The instrument features a 30-cm Cassegrain te lescope with a field of view of 8.5 x 8.5 arc min and a spatial resolution of 1 arc sec (0.5 arc sec pixels). TRACE contains multilayer optics and a l umogen-coated CCD detector to record three EUV wavelengths and several UV w avelengths. It observes plasmas at selected temperatures from 6000 K to 10 MK with a typical temporal resolution of less than 1 min.