Meddelanden Från Astronomiska Observatorium, Uppsala, Issues 19-29Wretmans Boktryckeri AB, 1927 |
Other editions - View all
Common terms and phrases
absolute magnitudes absorption according anagalactic apparent magnitude Arkiv för matematik Asklöf assume astronomi atoms band G BERTIL LINDBLAD calculated catalogue centre comparison stars computed constant corresponding curve decrease density determined diagram dispersion displacement distance distribution double stars EDDINGTON EDDINGTON's theory effective wave-lengths energy line error of plate estimated evolution frequency galactic plane giant stars globular clusters Greenwich hour angle hydrogen hypothesis hydrogen lines investigation LINDBLAD locus line log EG luminosity formula LUNDMARK main series mass reduction measured nebulæ Normal Equations number of stars Observatory observed obtained open clusters orbits parallax star parsecs Petersson photographic magnitudes plate of unit Probable error proper motion r-type radiation region result Sept smaller spectral class spectral groups spectral type speed of rotation spiral stars of types stellar system sub-system Table temperature tion type stars Upsala velocity
Popular passages
Page 88 - ... merits attention because of its bearing on the relation of globular to open clusters and of open clusters to the star-fields of the galactic system. Using an intensifying device in connection with the 100-inch reflector, thus gaining about one magnitude in the photographic limit of the telescope, Mr. Shapley believes he has recorded the faintest stars existing in the globular cluster M 22, and there are indications that the lower limit of brightness has also been approached in the Hercules cluster,...
Page 36 - The general characteristics of the frequency function of stellar movements as derived from the proper motions of the stars».
Page 100 - This seems to me to be the explanation of the fact that it is just in these close systems we find the smaller masses to be more diffuse.
Page 4 - R.-D. began to be generally thought of as a proof of the continued development of the stars from the giant stage to the dwarf stage.
Page 4 - The time did not permit me to go over all the plates available for the purpose.
Page 7 - The correlation found is not very high but should probably be taken as real. We have to remember that many of the absolute magnitudes derived are somewhat uncertain, besides that no seclection of the material has been made. Besides, also the Cepheids have been included. The following regression lines have been derived from the material: P = 4,835ee + 0,8108, e = 0,0973 P + 0,0864, J/= 0,360 € + 1,586, e = 0,032 M + 0,273. Observatory Upsala 5 March, 1927. Corrigenda. In Table I and Table II the...
Page 35 - Mx where x is positive in the former case, and negative in the latter. If one consider the influence of the ionisation on the molecular weight of no importance in comparison with the last-mentioned effect, it is at any rate hopeless to read this effect out of MLD If one supposes x positiv, for example x = %, then, for...
Page 5 - Then a number of the starlike nebulae were compared with the stars. These nebulae were used as a kind of secondary standards in order to obtain the magnitudes of the nebular objects showing a more definitely extended surface. As a rule the estimates were rather accordant. In some cases uncertainties are involved because of the comparison of objects situated in different parts f the plates.
Page 3 - Let u, v, w be the components of velocity of the centre of mass of a small Volume at a certain point of the system when referred to a coordinate system x, y, z of angular speed of rotation...