The Tycho-2 Catalogue
Frequently asked questions
They can no longer be ordered from ESA since the printed volumes
have been sold out, but they are available in many scientific
libraries. Moreover, the volumes 1-11 are available on the web:
Hipparcos and Tycho Catalogues.
The data on the CD-ROMs are available at the
Strasbourg Data Centre
from where all astronomical catalogues may be obtained.
An overview of all kinds of
astronomical catalogues has been placed at the homepage of
the US Naval Observatory by Zacharias et al. (2004):
Information and Recommendations"
There is indeed a problem with HIP 11767, but it is not
HIP 11767 is TYC 4628-237-1.
Tycho-2 gives, as always, the observed position on the sky and also the two-colour photometry. What is missing is the proper motion. About 4% of the Tycho-2 stars were not found is the ground based catalogues which we used for determining the proper motions. For these stars we are therefore unable to provide the epoch 2000 mean position and proper motion. What we do give, is the observed position, which was observed at an epoch around 1991.5. You should check the "mean position flag" in column 14. This flag distinguishes between three kinds of Tycho-2 stars:
In a good textbook on astrometry, or on the Hipparcos homepage in Volume 1 of the Hipparcos and Tycho Catalogues (ESA 1997) available at the link given at the top of the page; see Section 1.5.
Tycho-1 epoch photometry is provided in the Annexes A and B for
481553 Tycho Catalogue objects (see Section 2.6 in
Volume 1 of the Hipparcos and Tycho Catalogues (ESA 1997) available
at the link given at the top of the page.
Annex A is provided on disc 4 of the ESA CD-ROMs. Please
ask Strasbourg directly to get the Annex B.
Tycho-2 epoch photometry has not been published, and will not be.