Engineering topics
Publications and source records attributed to Vonthuna, P. C..
Lunar sample measurements were made both under ambient nitrogen pressure and under vacuum conditions. Average emittance values were analyzed for a number of samples which were determined to include silicate minerals, pyroxenes, and fine particle feldspar. Information is also provided on modifications made to emittance apparatus in order to work with smaller sample sizes and to prevent accidental loss or contamination of the lunar sample material.
Grating is used in place of required folding mirror. Arrangement eliminates separate monochromator unit and uses retroreflector for alignment.
The first infrared heterodyne spectrometer using tuneable semiconductor (PbSe) diode lasers has been constructed and was used near 8.5 micron to measure absorption line profiles of N2O in the laboratory and black body emission from the Moon and from Mars. Spectral information was recorded over a 200 MHz bandwidth using an 8-channel filter bank. The resolution was 25 MHz and the minimum detectable (black body) power was 1 x 10 to the minus 16th power watts for 8 minutes of integration. The results demonstrate the usefulness of heterodyne spectroscopy for the study of remote and local sources in the infrared.