TRACE

TRACE (Transition Region and Coronal Explorer) was a NASA Small Explorer Program (SMEX) satellite launched in 1998 and operational until 2010, to investigate the solar magnetic field by observing the fine structure of the corona from visible light to far ultraviolet. It was a 30-cm telescope imaging with a CCD, with filters and coatings of parts of the mirrors to separately sense various passbands. The CCD resolution was 0.5 arcsecond per pixel and the field of view was 8.5×8.5 arcminutes.