In 1996, one year after we bought our first ccd camera (OES LcCCD11n running the KAF-0400 CCD device), we started our first attempts in spectroscopic observations, because we were amazed about the power of the ccd technology. First we used a slitless prism spectrograph, but soon we learned, that we have to build our own slit spectrograph, because we are mainly interested in spectroscopic observations of comets.
The first spectrograph (now called YASSP1) was finished in October 1996 (too late for surprising comet Hyakutake in March), but we were able to make our first spectras of comet C/1996Q1 (Tabur). The second spectrograph was only a mechanical re-design of the first one, but essentially with the same optical components. This one (YASSP2) was used for our observations of C/1995O1 (Hale-Bopp) in 1997. On comet Hale-Bopp we were able to confirm the sodium tail on 1997-04-20, discovered three days ago at the Roque de los Muchachos observatory at La Palma (see IAUC 6631). But we believe, that a weak emission at 589nm visible on a single ccd image, taken on 1997-04-06, is a "true" cometary line.
After a break due to personal reasons, we continued our team work on comet C/2002C1 (Ikeya-Zhang) using the YASSP3 spectrograph. We appreciate it very much that we still have access to the University of Siegen observatory, where this first observation was made in April 2002.
Status: Project finished. Not longer active