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Milligan, J. E.

Publications and source records attributed to Milligan, J. E..

11 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1985

Electrets and plant fluorometers used in field studies to measure hydrogen chloride produced during Space Shuttle launches

The results of the field tests of two monitoring device techniques, electrets and plant fluorometers are analyzed in order to determine the environmental effects of launch by-products and the extent of these effects. The STS launches are used because the Shuttle emits 2 1/2 times more HCl than any previous systems, it produces a voluminous ground cloud and, most important, it produces near field HCl deposition and revolatilization, far-field acid washout/rainout, and gaseous HCl diffusion. Field evaluations of electrets at STS-5, STS-6, and STS-8 have shown that qualitative assessments can be made for areas lightly or moderately impacted by gaseous and aerosol HCl. Field evaluation of the plant productivity fluorometer at STS-8 has shown that this system is also useful for qualitative assessment in areas lightly, moderately, or heavily affected by gaseous and aerosol HCl. Quantitative prediction of HCl may be possible in lightly and moderately affected areas, given deposition rates correlation.

Milligan, J. E.↗
NASA NTRS1976

S056 X-ray telescope experiment on the Skylab Apollo Telescope Mount

This paper describes the S056 X-ray instrument which was carried aboard the Skylab Apollo Telescope Mount as part of the solar instrument cluster. The instrument, which was built at the NASA Marshall Space Flight Center, consisted of a glancing incidence X-ray telescope to record solar images in the 6-40-A region, together with an X-ray event analyzer to monitor the total solar soft X-ray flux in several wavelength bands. The X-ray telescope used film as a recording medium and thin foil filters to isolate specific wavelength bands. The instrument subsystems are described in detail and typical results presented.

Underwood, J. H.↗
NASA NTRS1975

Initial results from the S-056 X-ray telescope on Skylab

The S-056 instrument on Skylab-ATM consists of a glancing incidence X-ray telescope with a camera, five X-ray filters, and two small proportional counters to monitor X-rays from the whole sun in the wavelength range from 2 to 18 A. The telescope reflectivity and filter transmissions limit the photographs to the wavelength ranges from 6 to 18 A and from 27 to 37 A. Hence, the instrument is most useful for the study of active regions and solar activity. Active regions usually have bright cores which often appear as linear features straddling the magnetic field neutral line. A large loop appearing on the west limb in connection with prominence activity on Aug. 13, 1973, was analyzed using proportional counter data and photographs. Crude spectral analysis indicates the loop temperature reached 6 million K and the density was enhanced to a few times that obtained from quiet coronal models. Over a hundred solar flares were photographed during the three Skylab missions. Illustrative examples are discussed for solar flares and other transient coronal phenomena.

Mckenzie, D. L.↗
NASA NTRS1974

Analysis of Skylab/Apollo Telescope Mount S-056 observations based on a force-free magnetic field model

Data obtained from the S-056 X-ray experiment on Skylab/ATM have been analyzed based on the assumption that the magnetic fields in the chromosphere and lower corona are force-free. Underlying the analysis is the hypothesis that the observed X-ray filaments coincide with magnetic field lines. The photographic recording of the filaments can then be compared with the projection along the line of sight of the computed magnetic field lines of the model. Ground-based observations of the longitudinal magnetic field component complement the X-ray data and are used in the theoretical interpretation.

Meyer, R. X.↗