UBVRI Standard Stars at Northern Declinations Accurate values of V, B--V and U--B are given 123 stars of magnitudesfrom 6 to 11 at high northern declinations. For 36 stars also V--R andR--I color indices are given.
Lightcurves of selected minor planets. We present 81 photometric lightcurves of 36 minor planets observed inthe V and B bands at the ESO 50 cm telescope at La Silla (Chile). Theseasteroids were selected preferentially in order to improve theirecliptic longitude coverage in view of pole determinations andlightcurve inversions. We also give some first photometric observationsand/or rotational period for several asteroids.
A study of some stars with circumstellar dust envelopes. I We present the results of a study of circumstellar dust envelopes of 36stars of early(O-B-A) types in the directions of the associations CasOB1, Cas OB2, Per OB1, and Ori OB1. We determine the absorption at 1640Å, the linear radius of the dust envelopes, the mean value of thecoefficient k, and the masses of the envelopes. They differsignificantly from one another.