The Odessa Astronomical Observatory has three collections of Sky Patrol negatives, which have been exposed since the beginning of the 20th century. Altogether, there are about 100,000 negatives of the stellar sky, covering a declination range from −15 to +90°. The limiting stellar magnitudes are 15 (photographic - pg) and 12 (photovisual - pv), respectively.

The Schmidt telescope (360-333-625 mm) of the Abastumani Astrophysical Observatory has been used for photographic observations for more than fifty years. It provides a field of 7°.3 (80 mm) and a non-vignetted field of 4° (44 mm). A limiting magnitude of 16m.5 can be reached in 7-8 min exposure on medium sensitivity astronomical films and 18m with fine grain emulsions.

Multicolour and polarization observations of a few hundred relatively bright galaxies were carried out by M. Vashakidze during the first two decades of the telescope operation. In the mid-1950s, he also discovered the strong polarization of the Crab nebula. Since 1961, systematic photographic observations are carried out in the framework of the International Cooperation Programme of Supernova Patrol in 24 fields. The telescope is also used to study the brightness variations of eruptive and exploding variable stars.

The current status of a database containing information on wide-field observations stored in plate archives all over the world is presented. The database will permit on-line access to information on nearly 2 · 106 wide-field (⪆ 1 degree) plates and films, obtained over more than a century with about 200 telescopes and cameras.

The astrometric aspect of cataloguing variable stars becomes more and more important. During the past thirty years there has been approximately an three-fold increase of the number of known variables; now the rate of new discoveries becomes extremely high, and we may expect a new twofold increase in a couple of years due to discoveries made with space-borne instruments. To avoid confusion, we should continue our policy of naming new variables, and this is impossible without checking identifications with known variable stars, requiring good coordinates and/or finding charts. Operation of automatic telescopes also needs excellent coordinates just for pointing. For all these reasons, we are now working on improving considerably the accuracy standard of variable star coordinates, providing at least reasonably good coordinates for extragalactic variables (GCVS, 4th Edition, Vol. V, now in press, gives coordinates mainly to a second of arc) and variables in globular clusters, identifying variables, including those with rough published positions, with positional catalogues, etc.

Flare stars are very important variables; potentially they are one of the most abundant types of variable stars. Their identification in minimum light may be rather complicated, especially for dense regions of star clusters and associations. Most regretfully, there are many cases of papers on flare stars introducing additional confusion connected with wrong designations, wrong coordinates, missing finding charts. Thus, there appear problems preventing us from incorporating some flare stars in the GCVS. Many definite variables remain in the status of “suspects”, being positionally close to known variables, and no finding chart being available either for the earlier known variable or for the new one. Sometimes we do include such a “pretender” into the GCVS, and years after a finding chart or good coordinates appear, and it turns out that we have two entries for the same star (see, for instance, numerous cases of duplicated names for flare stars in Taurus in the GCVS Vol. III).

Neutron stars were not expected to be observable in the extreme ultraviolet and hence their detection in this band is a surprise. More important is that EUV observations provide unique new information on these objects. In the accompanying Table 1, I list the neutron stars detected in the EUV with the Extreme Ultraviolet Explorer (EUVE). The binary object Her X-l is the only object detected in the all sky survey. This is not surprising since it is the only neutron star system with sufficient intensity to be detectable in the 500 to 2000 second sky intergrations which are typical for the EUVE all sky survey. All the neutron stars were detected in the 100 Å (Lexan) bandpass. A more complete description of EUVE and the all sky survey are provided in Bowyer and Malina (1991), and in Bowyer et al. (1994).

An overview over the mission of the X-ray astronomy satellite ROSAT (Röntgensatellit) is given with an emphasis on the first soft X-ray all-sky survey carried out with an imaging telescope. Several examples of time variability studies made possible by the all-sky survey are shown for active late-type stars. Two exceptional long-duration stellar flares are presented.

Recent observations of the ASCA satellite resulted in the first identification of a GB source (Murakami et al. 1994). This success confirmed the importance of simultaneous observations in different wavelength bands for GB studies. Besides the ASCA results, there were several observations of GBs in X-ray band with the Ginga (Yoshida et al,.1989), V 78/1 (Laros et al. 1984) and other satellites. It became clear that GBs emit 4 - 8% of their energy in the 2 - 10 keV range. The main task now is to have an equipment which will be able to monitor the sky in X-rays in a mode similar to that of GRO observations, i.e. the telescope should have an all-sky field-of-view (FoV) and should work continuously.

A telescope with these features but operating at soft X-ray energies may directly determine the GB distance scale, due to interstellar absorption of the photons with energies less than 2 keV, as was pointed out first by Schaefer (1993). Flaring sources similar to GBs in time scale may be found also in the EUV (hundreds of angstroms) with the help of very wide-field cameras. Of course each such device - in X-ray, soft X-ray and EUV bands - will discover many transient objects, flaring events, will study time variability of bright “stationary” sources etc. In this paper we describe several instrumental approaches in these fields.

Classical X-ray mirror optics usually has a limited Field of View (FoV) of ∼ 1°. Wide-field imaging can be achieved by lobster-eye type reflecting X-ray optics. We summarise several different approaches and suggest an innovative technology for the production of X-ray reflecting flats and cells necessary to develop one- or two-dimensional wide-field X-ray optics. The technology is based on double-sided, replicated reflecting foils produced by electroforming and CF/composite technologies.

The goal of this round-table discussion is to bring up issues which may be of mutual interest to those working on specific flare and variable stars and those performing wide-field searches for, among other things, counterparts to gamma-ray bursts (GRBs). Admittedly, however, trying to unify the interests of the flare people and the GRB people will be an interesting task. Many of the presentations this week have been devoted to future instrumentation and future modes of observations, but there have been also interesting discussions of specific questions regarding flare stars, variable stars and GRBs. Certainly, wide-field observations of the night sky will continue for the foreseeable future: there are a lot of instruments running now, and there are many instruments being planned. Most of these observations cover many square degrees of sky for long periods with a reasonable magnitude limit. How could these observations could be modified or improved to also allow useful data on on variable stars or flare stars to be taken? What sort of information, statistics, periodicities could be gleaned from wide-field searches that will be happening in the future and searches that are going on today? Are there methods in common use by one group of observers that may be useful to the other?

The speakers in this session have volunteered to give a short presentation on issues which may benefit from discussion within this group.

It was exactly 22 days before Cuno Hoffmeister’s 65th birthday when I began my work at Sonneberg Observatory, following my studies at the University of Jena. In those days, all Sonneberg astronomers were busy preparing scientific papers which they were going to dedicate to their leader, with the exception of myself. I was not able to write a scientific paper in such a short time.

And I was quite ashamed when on the 2nd of February 1957 I had to offer my birthday congratulations empty-handed. But I distinctly remember how extremely happy he looked. Hoffmeister was near the zenith of his scientific career. New buildings and domes were planned or under construction, and the Zeiss company of Jena had promised to loan a 40 cm astrograph in compensation for the loss of a telescope to the Soviet Union as part of the reparations agreement of 1945.