After the successful launch of the SOHO satellite on 2 December 1995 and
after the commissioning and performance verification phase regular
scientific operations were taken up in April 1996.
The Coronal Diagnostic Spectrograph (CDS), for which MPE developed
and built together with Carl Zeiss the Wolter type II telescope with
an angular resolution of less than two arcseconds, performs to
expectation and delivers excellent spectra and images since then.
In the institute some first scientific programmes have been set up,
for which the IDL based SOHO data analysis software was installed.
The analysis of the first GIS spectra (grazing incidence spectrograph)
has begun. The line complex of FeIX - FeXII between 170 and
200 Å is well resolved and turns out to be very similar
to the EUVE spectra of nearby inactive stars measured by us.
In another project the spatial and thermal morphology of solar spicules
is being analysed. The work concentrates on regions from the
chromosphere up to the narrow temperature transition zone.
Furthermore, the post-eruption behaviour of active solar regions
will be studied. It is conjectured that in active regions strong density
inhomogenities are generated followed by plasma motion and reconnection
which are accompanied by radio storms. Accordingly, also ultra-violet,
optical and radio measurements will be used. With CDS it has become
possible to study all of these phenomena with unprecedented resolution
in time, in space and spectrally.