Issue |
Astron. Astrophys. Suppl. Ser.
Volume 124, Number 1, July 1997
|
|
---|---|---|
Page(s) | 189 - 196 | |
DOI | https://doi.org/10.1051/aas:1997189 | |
Published online | 15 July 1997 |
Absolute stellar proper motions with reference to galaxies of the M 81 group
1
Sternwarte der Universität Bonn, Auf dem Hügel 71, D–53121 Bonn, Germany
2
Thüringer Landessternwarte Tautenburg, Sternwarte 5, D–07778 Tautenburg, Germany
Send offprint request to: M. Odenkirchen
Received:
22
August
1996
Accepted:
4
November
1996
We report on the measurement of absolute proper motions of
stars of magnitude 7 to 14.5 in a field in
the region of the M 81 group of galaxies.
This work is part of the Bonn program for the extragalactic link
of Hipparcos. The proper motions were
determined from a collection of photographic plates covering the
time interval from 1894 to 1994. The absolute reference system
for the proper motions is represented by the galaxies M 81, M 82
and NGC 3077, for which accurate optical reference positions
were obtained by means of an image cross-correlation technique.
For the majority of stars, the internal proper motion accuracy
is better than 1 mas/a. The precision of the realization of the
absolute system is found to be around 1 mas/a. In total, our
measurements yield absolute proper motions for 24 Hipparcos stars
and positions, proper motions and photometry for 330 additional stars
including a number of visual binaries and high proper motion stars.
Among the latter one G-type sub dwarf is identified.
The results are relevant as a contribution to the Hipparcos link,
but also as a database for kinematic investigations.
Key words: galaxies: M 81 / astrometry / reference systems / catalogs
© European Southern Observatory (ESO), 1997