Abstract
THE George Darwin Lecture entitled “Some Phenomena connected with Interstellar Matter ” was delivered by Prof. J. H. Oort before the Royal Astronomical Society on May 10, 1946, and the lecture has now been published in full (Mon. Not. Roy. Astro. Soc., 106, 3; 1946). Prof. Oort deals more with a survey of the problems presented by interstellar matter than with an account of our present knowledge on the subject. The uneven distribution of interstellar matter is the first characteristic that strikes the investigator, and this applies to interstellar gas as well as to obscuring clouds. On the average, the light from a star 1,000 parsecs distant traverses five clouds, and it can now be accepted that the dark clouds contain proportionate concentration of gas. It has been shown that, on the average, the intensities of interstellar lines increase proportionally with the distances of the stars in all galactic longitudes, the only explanation of which is that these lines are mainly formed in clouds having ‘peculiar’ velocities averaging 15 to 20 km./sec. in the radial component.
Article PDF
Rights and permissions
About this article
Cite this article
Interstellar Matter. Nature 160, 203 (1947). https://doi.org/10.1038/160203a0
Issue Date:
DOI: https://doi.org/10.1038/160203a0