Though the evidence of rapid variability in early-type stars is rather old, we have passed through the ignition stages of a more recent information explosion on this subject. This explosion started with introduction of new detectors capable to detect even very subtle variations. But the old evidence based on much important changes remains. Different types of rapid variability in 0, B, UR and CP2 stars and their relation are discussed.
Hledání extrasolárních planet je poměrně mladým a velmi rychle se rozvíjejícím odvětvím astronomie. Od prvního objevu roku 1995 bylo nalezeno 117 extrasolárních planet a řádově stovky hnědých trpaslíků. Současná teorie vzniku planet z protoplanetárních disků ukazuje, že vznik planet není ve vesmíru ničím výjimečným, zároveň však mnohé objevy extrasolárních planet naznačují, že tato teorie má doposud značné mezery. Planety mohou vznikat i přímou fragmentací zárodečného oblaku vlivem gravitačních nestabilit. Stručně jsou shrnuty základní poznatky o vzniku a vývoji planetárních systémů a hnědých trpaslíků, je uveden popis nejpoužívanějších detekčních metod., Jakub Rozehnal., and Obsahuje seznam literatury
A particle path formula has been derived for charged particles spiralling in extended magnetic and gravity fields, In part I (Book 1, 3CS 1), a stationary dipole- like magnetic field has been considered in which particles of the highest energies slowly but continuousely diffuse up and fill the tops of very extended field
lineš, while underescape charged paťticles diffuse down and separate from its top-trapped highTenergy part, Below an impact which squeezes the magnetic tubes the field strength H decreases less thon before or even grows with altitude r, in this region.
Consequently the pitch angle of all down spiralling particles increases less now and vice versa; The plasma shifts down, it streams down even without having gained any energy surplus, The bottom of the Van Allen belt shifts down there and rises os Soon
as the impact has ceased, This explains the oocurrence and disappearence of aurorae, When the H(r)-variation changes so that H=const is passed, without gravity the mag¬ netic mirror would immediately switch from the bottom on the top, In the gravity
field first a "hole effect" gradually reverses the path - between H=const and r“^’ Phenomena occurring now apparently violate some basic physical laws.
Je tomu již 12 let, co se ze skromného setkání studentů z Astronomického ústavu AV ČR v Ondřejově stala tradiční konference s mezinárodní účastí. INTEGRAL & BART Workshop (IBWS 2015) se zpočátku jako hlavním tématem zabýval pozorováním gamma záblesků vesmírnou družicí Evropské kosmické agentury INTEGRAL, jejichž optické protějšky se snažil na Zemi detekovat robotický dalekohled BART. Zaměření se v astronomii ukázalo jako aktuální, a tak letos v Karlových Varech prezentovalo své příspěvky na 40 inženýrů, vědců a studentů z České republiky, Německa, Itálie, Maďarska a Španělska. and Martin Blažek.
Methods of processing of VEGA-TV observations of the nucleus of P/Halley and derived scientfic results are summarized. The existence of lineamentary surface structures is interpreted as an indication for boundary zones between km-sized blocks, building the cometary nucleus. The consequences for cometary origin are investigated.
From accelerometer total density data collected during the last minimum of the solar cycle, density scale heights have been extensively computed. Effects of waves dissipation are evidenced on this data set which reflects temperature behaviour. It appears that tides of high orders (or planetary waves) are quite significant and variable.
It is argued that spiral patterns in galaxies generally are transient features which will decay away in a few dynamical times, only to be replaced by other similarly short-lived waves. The evidence for this point of view is presented and the current state of the theory is discussed. A major consequence of such behaviour is that disc stars are scattered into gradually more eccentric orbits by successive spiral waves. This has two further implications: (a) the velocity dispersion of stellar populations will increase with their ages and (b) persistent spiral structure demands a gas component in the disc that can dissipate some of the random moiton energy. That the theory offers such a matural explanation for these two well established aspects of galactic structure is cited as indirect evidence in its favour.