Engineering topics
Publications and source records attributed to Rahe, J..
The far-UV spectrum of the eclipsing binary UW CMa (O7f + O-B) had earlier been utilized to derive a mass-loss rate of about 0.000001 to 0.00001 solar mass per year. The mass flow seems to be basically in the form of a stellar wind emanating from the O7f primary component, with radiation pressure as the controlling factor. The main characteristics that make UW CMa a possible progenitor of a Wolf-Rayet system are discussed.
Coude spectrograms of comet Kohoutek obtained with the ESO 152-cm telescope in La Silla, Chile are discussed. Emission features of the C3, CH, and CO(+) molecules found in the blue region of the spectrum are considered along with measured emissions in the visual region of the spectrum. The observational and cometary data are given in tabular form.
Isophotes have been determined from 10 narrow-band filter photographs of Comet Tago-Sato-Kosaka 1969g (1969IX) taken between Feb. 11 and 14, 1970. The five interference filters used were centered on the CN band sequence at 3383A, the C2 band sequence at 4737A and 5165A, the C3 sequence at 4050A, and the continuum at 5300A. Gradients of intensity in various directions from the nucleus have been derived from the isophotes.
Isophotes have been determined from 32 photographs of Comet Bennett 1969i (1970II) taken during the period from March 28 to April 18, 1970. The six interference filters used were centered on the CN band at 3383A, the C2 band sequences at 4737A and 5165A, the CO(+) band at 4277A, on the sodium D-lines at 5893A, and the continuum at 5300A. Intensity gradients have been derived from these isophotes.
Examination of the relations between the solar-wind and Comet Bennett during the period from Mar. 23 to Apr. 5, 1970. A large kink was observed in the ion tail of the comet on April 4, but no solar-wind stream was observed in the ecliptic plane which could have caused the kink. Thus, either there was no correlation between the solar wind at the earth and that at Comet Bennett (which was 40 deg above the ecliptic) or the kink was caused by something other than a high-speed stream. The fine structure visible in photographs of the kink favors the second of these alternatives. It is shown that a shock probably passed through Comet Bennett on March 31, but no effect was seen in photographs of the comet. A stream preceded by another shock and a large abrupt change in momentum flux might have intercepted the comet between March 24 and March 28, but again no effect was seen in photographs of the Comet.
Observations of the solar wind and the comet Bennett made during the period from Mar. 23 to Apr. 5, 1970 are considered. During this period the position of the comet had been comparatively close to earth at a distance of about 0.7 AU. Plasma data from four space probes and photographs of a number of observatories are taken into account. The relation between a sudden change in the velocity of the solar wind and the occurrence of a pronounced disturbance in the cometary tail is investigated.
The relations are examined between the solar-wind and Comet Bennett during the period 23 March to 5 April 1970. A large kink was observed in the ion tail of the comet on April 4, but no solar wind stream was observed in the ecliptic plane which could have caused the kink. Thus, either there was no correlation between the solar wind at the earth and that at Comet Bennett (which was 40 deg above the ecliptic) or the kink was caused by something other than a high-speed stream. The fine structure visible in photographs of the kink favors the second of these alternatives. It is shown that a shock probably passed through Comet Bennett on March 31, but no effect was seen in photographs of the comet. A stream preceded by another shock and a large abrupt change in momentum flux might have intercepted the comet between 24 March and 28 March, but again no effect was seen in photographs of the Comet. In view of these results, the possibility must be considered that a large, abrupt change in momentum flux of the solar-wind is neither necessary nor sufficient to cause a large kink in a comet tail.
Comets structural features via visual observations, emphasizing inner coma structures and expanding envelopes surrounding nucleus
Comet tail structures in inner coma region using photographic observations
Comet interaction with solar wind, assuming field tail coupling of ionized comet material to solar wind ions
Atlas of drawings and photographs of comets
Tail ray structure in comet coma region from visual and photographic observations of various comets