In a recent paper (Olah et al., 1985) we found that the active areas of UK Lac exhibited sometimes smali, sometimes large scale motions. In the case of the Sun it is well knovvn that new spots exhibit large proper motions while the old ones move almost together with the surrounding photosphere. On UK Lac both a newly formed active area and an existing old one showed rapid motions at the same time. A possible interpretation of this phenomenon is that new spots appeared in both the new and the old active areas simultaneously. This time coincidence may be aceidental, but if spots originate in dceper layers, than spots of common decp origin may appear in remote places of the stellar surface at the same time. Similar phenomena are seen on the Sun, when we observe simultaneous emergence of new flux in various parts of an extended active region (Zirin, 1983). The distribution of the active areas on the surface of HK Lac during the past eight years, is
discussed.
In a previous study of the A-type supergiants observed with IUK we divided these stars in two groups, the most luminous ones, which showed clear evidence of stellar wind and mass loss in their line profiles and the less luminous ones which did not show these characteristics. New observations of some A supergiants confirm the difference between those two groups. Moreover the less luminous (Ib) A-type supergiants do show weak signs of wind and mass loss compared with the most luminous A supergiants and their variation is more spectacular.
Various instruments were used to observe the solar corona and prominences near or at the time of solar eclipse, 22 July 1990. The white-light solar corona pictures were observed nearly up to R = 3 (solar radii) with the Úpice Observatory eclipse team at Markovo. Both emission line intensities (the green and red corona) and prominences were obtained at Lomnický Peak coronal station. These data sets are used to identify active coronal regions. A large coronal hole was observed above the south pole and extending nearly up to R = 2.5. Large-scale structure of the white-light corona is very complicated. There are many streamers nearly equally distributed around the whole Sun (except the south pole). Several streamers above the solar surface are not extended radially with
their height. In the NE quadrant 4 voids are clearly seen at the height of about R = 2. A slight excess of the white light corona is in favor of the west limb, however, the emission corona has an opposite meaning. Green and red corona, similarly as prominences, showed rapid changes in active regions over the eclipse period, however, any CME was not directly observed. The integral brightness of the 22 July 1990 white-light corona was estimated as JK = 1.32 x 10~6 and the ellipticity, a + b = 0.04. The white-light corona was nearly a maximum type.
The supplement contains corrections and new data of the past observation of north polar aurorae (< 55° N). and Reprinted from Travaux Géophysiques XXXVII 1993-1996
Mrk 3 is an early-type galaxy, probably a transition case between E and SO. Analysis of the isophotes clearly shows a disk component along the major axis. A large extended emission line region (EELR) was found. It is confined to a disk along the minor axis, perpendicular to the stellar disk component. The radio-jet of Mrk 3 is almost perpendicular to the stellar disk and has a small inclination only against the EELR.
The ionization mechanism and dynamical state of the EELR was studied from several longslit spectrograms both along and perpendicular to the EELR extension. Both, [OIII]/Hβ and [NII]/Hα clearly indicate that the spectrum of the NLR deviates from HII regions. The line ratios are similar to the values found for the NLR of Mrk 3, indicating that the powerlaw source is responsible for the ionization out to several Kpc.
Off-centre spectrograms indicate that the kinematics is governed by rotation and an additional inflow motion. This accretion flow could have velocities as large as 20 km/sec. It is speculated that the unusually broad and asymmetric lines of the NLR indicate a close interaction with the velocity pattern of the EELR.
The maln sequence rnass functlon of violent star formation regions are investigated by means of observations of extremely young star bursting dwarf galaxies (HII galaxies). The effective temperaturs of the total ionising radiation in these systems decrease more steeply with abundance than expected from metallicity dependent changes in the internal structure of the stars and from the decreased cooling in the nebulae but can be explained if the mass function varies systematically with chemical composition.
The Taurid meteor complex associated with P/Encke Is studied on the basis of relevant photographic and radar orblts. Orbltal characteristlcs, radiants and durationa of the postperihelion
showers are compared with correspondlng theoretlcal values derived from the observationn of the preperihelion Taurlds, Reality of the proposed assoclatlons of mlnor showers with the Taurld complex and the total duratlon of Its actlvilty are evaluated and discussed. Some of the associated showers the Northern and Southern X Orionids, Northern Piscids and Southern Arietids) are confirmed to be In fact parts of the Taurid shower itself.
The present definition of U.T.1 is a complex one which introduces the old concept of the ”Fictitious Mean Sun” which has been
suggested by Newcomb (1895). The conventional right ascension of the Fictitious Mean Sun brings the basic relationship between Sidereal Time, arising directly from observations, and U.T.1, as it is internationally adopted. Unfortunately, this basic relationship needs some effort of understanding for the common user. It is the reason
why B. Guinot (1979) proposed to adopt another point instead of the vernal equinox on the celestial equator, that he called the
‘non-rotating origin σ’. This point obeys to a clear kinematical
concept. Moreover, it should bring a new conceptual definition of U.T.1 very easy to understand. The position of σ on the celestial sphere can be easily determined by the Eulerian angles ψ and θ which are positionning the instantaneous axis of rotation of the Earth relatively to an inertial plane of reference. It can also be realized by the way of a quantity 's’ depending on the only motion
of the instantaneous equator. Formulation and developpement of ‘s’ are successively given.