Ústav technické a experimentální fyziky ČVUT v Praze realizuje v ČR ve spolupráci s Filozoficko-přírodovědeckou fakultou Slezské univerzity v Opavě unikátní projekt detekce vysokoenergetických spršek kosmického záření, který má vedle vědeckého též pedagogický dopad. Cílem projektu je vybudovat síť detekčních stanic a zapojit se tak do globální detekční sítě, která má za úkol přispět k vyřešení fundamentálních otázek spojených s oblastí kosmického záření. Podobně jak v dalších zemích EU, v Kanadě a USA, jsou i u nás detekční stanice umísťovány převážně na střechách vybraných středních škol a studenti těchto škol jsou aktivně zapojeni do tohoto projektu. To podporuje výchovu talentovaných studentů se zájmem o technické a přírodní vědy a zvyšuje atraktivnost takové výuky., Karel Smolek., and Obsahuje seznam literatury
Description d'un microphotomètre destiné aux besoins astronomiques. L'appareil travaille avec deux cellules à couche d'arrêt au sélénium (Tungsram S 44) par compensation optique à l'aide d'un coin neutre. Il en résulte l'indépendence de l'intensité de la source qui est une lampe de 100 W alimentée sur le secteur. On donne in théorie de l'instrument ainsi que le résultat des essaies pratiques.
HIPPARCOS satellite should be launched in 1989. It will measure positions, proper motions, and parallaxes of about 110 000 selected stars brighter than 13, with a precision of 2 milliseconds of arc. Accurate positions (up to 1.5 arc second at the date of observation) and magnitudes (up to O. Smag) have to be known in advance. The star selection has to be optimized with respect to both scientific priorities defined by the ESA Selection Committee, and to technical constraints for satellite operation. The Input Catalogue under construction contains stars selected among the 700 000 ones proposed in 1902 ty the worldwide astronomical community. The Input Catalogue consortium is in charge of making the identifications, providing the necessary data with the required accuracy, and making the selection. A first provisional version has been established in February 1987 and its content is described :
- "survey" of bright stars, about complete up to a limiting magnitude function of both galactic latitude and spectral type, about 55000 stars.
- Painter stars from proposed programmes : nearby stars ; stars with high proper motion ; variable stars, in particular Cepheids and RR Lyrae for distance scale calibration ; open cluster stars ; stars for galactic structure studies > stars in the Magellanic Clouds / stars for reference frame ; stars for linking to the extragalactic system ; minor planets.
A rough estimate of the star distribution versus spectral types and distance is presented. The fulfilment of important astrometric or astrophysical programmes is evaluated.
The physical conditions of a large variety of structures, such as giant HII regions, holes, shells and rings, present in the interstellar medium are reviewed. Such structures are thought to result from the energy input from OB associations in the form of ionizing radiation, strong stellar winds and supernova explosions.
The study of the effects produced by every single one of the energy sources is proposed here as the way to evaluate, understand, and relate the observed structures with a given energy input. In particular, predictions fron the study of the HII region evolution sround a stellar association are reviewed. Such an evolution , lasting 10^7 yr, accounts for the aging of the exciting stars. The resultant effects are then compared with the large (expecting and static) shells observed in our galaxy, and with alternative theoretical models.
A sequence of events, based on the observed properties and the theoretical models, is proposed here as a likely scenario for the evoluton of the environment of an OB association.
The star formation process in a molecular cloud core is effectively halted when the newly born stars remove the remaining gas cloud out of the region. We present analytical and numerical calculations
of the dynamical evolution of a young cluster, which we allow to deviate from or oscillate around exact Virial Equilibrium (V.E.), during slow and rapid gas removal. Our conclusion is that
deviations from V.E. can influence the final dynamical state of the 'nakeď cluster significantly.
We have studied the height dependent characteristics of the Evershed flow in the photosphere, chromosphere and chromosphere-corona transition region. We have used the Multichannel Subtractive Double Pass Spectrograph (MSDP) to
obtain line of sight velocity maps in Hα, the Meudon magnetograph for mapping the photospheric velocity field and the Ultraviolet Spectrometer and Polarimeter (UVSP) on the Solar Maximum Mission (SMM) spacecraft to obtain line of sight velocities in C IV, in sunspot regions. Our emphasis was on the large scale,
quasi-stationary characteristics of the flow. In the photosphere the velocity is low above the umbra and shows a maximum above the penumbra. In addition to the reversal of the flow in the chromosphere both the characteristic scale of the flow and the velocity are larger; the velocity maximum is located outside the photospheric penumbra. In the chromosphere-corona transition
region there is a clear tendency for a chromospheric-type Evershed effect with a predominantly horizontal flow. The velocity is greater than in the chromosphere, but the characteristic scale of the flow is about the same. In addition to the Evershed flow, C IV observations show upflows above the umbra with a velocity of about 15 km/sec.
The occurrence of LDE flares in the last three solar cycles
has been investigated. Generally, in all the cycles considered, LDE flares mainly originated during a 6-year interval of the respective cycle (2 years before and 4 years after the cycle maximum). The highest LDE flare occurrence was observed in the ascending phase of the 22nd cycle (monthly mean number in 1989 - 32, in 1970 - 19 and in 1980 - 14 LDE (M-X) flares).
The condition of measurement of precipitation from the year 1805 up-to the present time are defined. On the vasis of an analysis of the conditions and by comparison with the neighbouring stations a whole series of annual percipitation is homogenized. The original values in the period 1805-1830 are reduced for 8.7 %, the period 1840-1905 zemains unchanged, the period 1906-1951 is reduced partly for 10 % (Hlaváč), partly for 15 %. For the statement of long-range variability of the annual precipitation the method of double-time integral of precipitation deviations was used. The curves thus gained show a long-range variation having a contraty course regarding the secular curve of solat activity (90-year-rhythm).
The long-range relation of the variability of annual precipitation to the secular solar activity is expounded by the change of circulation (showing the width of the frontal zone). Further a close connection between the course of yearly precipitaton nd Ejgenson´s Index of Recurrency of Sunspots was found, which is evidently applicable for Central-Europe. Immediately after the maximum of Recurrency Index there is a characteristic decrease of precititation, closely following the minimum of Recurrency Index there is remarkable rise. On the ground of extrapolation of the acquired secular curves of precipitation and on the ground of physically justified correlation with long-range solar activity, a prognosis of the course of the annual precipitation up to the year 2000 is defined. At present the long-range course of precipitaton shows the minimum, in the years 1970-1990 the precipitation should reach the secular maximum.
(Rezjume) Cel'ju nastojaščego truda javljajetsja obobščenije svedenij iz teorii raspredelenija i pojavlenija solnečnych pjaten na diske Solnca. V etoj svojej rabote avtor ischodit kak iz rjada trudov drugich avtorov, tak i iz svoich sobstvennych trudov, pomeščennych v raznych žurnalach, dopolnjaja eti trudy nekotorymi novymi svedenijami. Eta rabota javljajetsja sozdat' obobščenoje predstavlenije o teorii raspredelenija i pojavlenija solnečnich pjaten na diske Solnca.
Nastojaščaja rabota, odnako ne zanimajetsja osveščenijem voprosov etoj teorii s obščej točki zrenija, tak kak boleje obščaja teorija ne byla do sich por v soveršenstve razrabotana. Eta teorija osnovljajetsja na opredelinii uproščennych predpoloženij, iz kotorych samymi prostymi javljajutsja sledujuščije:
1) Vse solnečnyje pjatna pojavljajutsja tol'ko na ekvatore, kotoryj vsegda prochodit po seredine diska Solnca, t. e. čto "korolevskij pojas" pojavljenija solnečnych pjaten možno sebe predstavit' v vide cilindra, na ktoryj smotrim v napravlenii normali i jego poverchnosti.
2) V dejstvitel'nosti predpoložim, čto grupy solnečnych pjaten sostavljajutsja iz odnogo pjatna okrugloj formy.
Eti predloženija pozvoljajut nam sozdat' vozmožno polnuju osnovnuju teoriju raspredelenija i pojavlenija pjaten, kotoraja neobchodima dlja ocenki rezul'tatov raznych statistik pjaten i iz kotoroj možno ischodit' dlja sozdanija boleje obščej teorii.
Nastojaščaja rabota zanimajetsja prežde vsego sledujuščimi voprosami: opredelenijem osnovnych otnošenij i funkcij, umen'šenijem količestva pjaten v napravlenii k kraju solnečnogo diska, količestvom pojavšichsja i isčeznuvšich pjaten na raznych rasstojanijach ot central'nogo meridiana, podsčetom količestva voznikšich grupp na vsem Solnce i srednej prodolžitel'nosti ich žizni i značenijem etich veličin dlja issledovanija periodičnosti solnečnych pjaten.