Supported by the Deutsche Agentur für Raumfahrtangelegenheiten (DARA)
under grant no. 50 OO 91060.
The TYCHO experiment onboard the HIPPARCOS satellite is a long term project
(> 15 years) divided into three main periods:
pre-launch period (theory and software development)
post-launch or nominal mission period (nominal data processing)
post mission period (reprocessing)
currently the project is in the post mission period and will culminate in
the release of the TYC, a catalogue containing around 1.000.000 stars up to
a limiting magnitude of V=12.5 mag with astrometric and photometric data of
an accuracy comparable to the FK5 stars (1500 stars). In addition to the
catalogue of mean magnitudes there will be a very big appendix available
containing all of the single measurements for every star in the mean
catalogue (around 130 "good" measurements/star). The TYCHO group in
Tübingen has been officially formed in 1985 in the frame of the TYCHO
Data Analysis Consortium (TDAC), an European collaboration. The team in
Tübingen is working in three main parts:
Detection, i.e. location of the "transits" and estimation of the
Transit Identification; i.e. identification of the real star "transits"
Photometry; i.e. calibration and reduction of the star transit
amplitudes to magnitudes
Some more information on HIPPARCOS and TYCHO may be found at
CDS or at
An overview of the data analysis has been presented at the ADASS
conference in Victoria, B.C. 1993 and is available on our
publications web page.
This paper has been published in
Crabtree D.R., Hanisch R.J., Barnes J., Astronomical Data Analysis
Software and Systems III, ASP conference series, Vol. 61, 147-150.