view Abstract Citations (7) References Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS A test for non-thermal radiation from Jupiter at a wave length of 21 cm. McClain, Edward F. Abstract Measurements of the radiation temperature of Jupiter have been made in the vicinity of 3 centimeter wave length by Mayer, McCullough, and Sloanaker (1958), Drake and Ewen (1958), and Alsop, Giordmaine, Mayer and Townes (1958). These measurements are all in reasonable agreement with measurements made in the infrared. The consensus of opinion therefore has been that the source of this radiation is probably thermal. Later, McClain and Sloanaker (1959) reported temperatures of approximately 6oo0K from Jupiter at a wave length of 10 cm. These measurements were slightly suggestive of rather rapid variations in the measured temperature as a function of t'me. Drake reported informally at the May 1959 URSI meeting on temperatures in the range of 2000 to 3000 degrees Kelvin at a wave length of 21 cm and suggested that this radiation might arise from Van Allen belts surrounding the planet. Stanley (1959) has measured temperatures as high as ~ooo0K to io,ooo0K at 32 Cm. This paper deals with a series 6f measurements at 1430.00 Mc made on 28 days during a onemonth period from May 14 to June i8, 1959. An attempt has been made to correlate what ma~ be a variable temperature with the density of solar particles as indicated by magnetic storms on the earth, with the 10 cm solar index and with System I and System II rotation. No correlation has been found with the 10 cm solar index. In the case of solar particles, the fact that Jupiter was in opposition at the time of the measurements would lead one to expect that particles causing magnetic storms on the earth following a flare on the sun might reasonably be expected to arrive in the vicinity of Jupiter a few days later (first suggested by Drake). No strong correlation of this sort has been noted in these measurements. However, there is a slight suggestion of elevated temperatures following an importance 3Y flare on May 10 and the intense aurora of May II and 12. Each of the 28 daily measures is the average of 4 or 5 drift curves taken over a period of 2 hours. When plotted against time, these 28 measurements are highly suggestive of a cyclical variation. An attempt has been made to correlate this data with System I and System II rotation. In the case of System I no significant correlation was observed but in the case of System II an elevated temperature has been noted at a longitude of 2000. This enhancement of about 30 per cent appears to lie between 1750 and 2250. While rather significant when subjected to a statistical test, the amount of data is limited and this conclusion should be considered tentative. Correlation might actually be more pronounced with a system differing from both Systems I and II but sufficient data is not available at the time this is written. The mean temperature obtained from all data is 24960K with a standard deviation of 4500. REFERENCES Mayer, C. H., McCullough, T. P. and Sloanaker, R. M. 1958, Ap. J. 127, II. Drake, F. D. and Ewen, H. 1. 1958, Proc. Inst. Radio Engrs. 46, 53. Alsop, L. E., Giordmaine, J. A., Mayer, C. H. and Townes, C. H. 1958, A. J. 63, 301. McClain, E. F. and Sloanaker, R. M. 1959, Proc. URSIIA U, Radio Astr. Symp. Paris 1958, 6o. Stanley, G. J. 1959, private communication. Radio A stronomy Branch U. S. Naval Research Laboratory Washington, D. C. Publication: The Astronomical Journal Pub Date: 1959 DOI: 10.1086/108034 Bibcode: 1959AJ.....64R.339M full text sources ADS |