Symbiotic Miras give a nice practical demonstration of the formation of bipolar and highly aspherical nebulae as a consequence of interaction in detached binaries. We believe that these binary systems are among the most promising candidates for the progenitors of bipolar planetary nebulae. We present a list of the optically extended nebulae known

Not Available

Not Available

Not Available

We present first results of the analysis of X-ray data (ROSAT PSPC and HRI pointings) and optical observations of the open cluster NGC 2451. This object consists of two different clusters A and B in the same line-of-sight at distances of 190 and 360 pc, respectively. NGC 2451A is one of the 10 nearest clusters, but has been little studied because

H &alpha luminosities are presented in order to study the Star Formation Rates (SFRs) of a sample of galaxies in compact groups from Hickson's (1982) catalogue. Although the comparison of the SFRs of the disk galaxies in our sample with those of a sample of field galaxies yielded no difference between the average SFRs for disk galaxies in compact