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Proceedings of the Joint Discussion: Radar Determinations of Planetary Motions

Published online by Cambridge University Press:  16 November 2021

I. I. Shapiro
I. I. Shapiro*
Affiliation:
M.I.T. Lincoln Laboratory*, Lexington, Massachusetts

Abstract

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Radar echoes have already been detected from Venus, Mercury, Mars, and Jupiter. Time delay measurements of high precision between Earth and Venus, as well as between Earth and Mercury, have disclosed significant deviations from the published ephemerides of these planets. Although new simultaneous solutions for the A.U., the relevant planetary masses, radii, and orbital elements have not yet been carried out, preliminary analysis indicates that the light-second equivalent of the A.U. is 499.0050 ± 0.0004 and that the corresponding kilometer equivalent is about 149 598 000 ± 100 (using c = 299 792.5 km/sec). The same analysis shows that, with respect to Earth, both Venus and Mercury seem to be ahead in their orbits relative to predictions. The radius of Venus appears to be about 6100 ± 50 km, in agreement with the most accurate optical determination. Doppler spread measurements show Venus to have a retrograde rotation with a period of about 247 ± 5 days. The celestial latitude of its axis is about – 85 ± 2 degrees.

Type
Part 4 Joint Discussions
Information
Transactions of the International Astronomical Union , Volume 12 , Issue 2 , 1966 , pp. 615 - 624
Copyright
Copyright © Academic Press 1966 

Footnotes

*

Operated with support from the U.S. Air Force.

References

1. Price, R. et al. Science, 129, 751, 1959.Google Scholar
2. The Staff of the Millstone Radar Observatory. Nature, 190, 592, 1961.Google Scholar
3. Mailing, L. R., Golomb, S. W. J. Brit. Inst. Radio Engrs., 22, 297, 1961.Google Scholar
4. Kotelnikov, V. A. et al. Radar Observations of the Planet Venus in the Soviet Union in 1961, Science Report of Institute of Radio Engineering and Electronics, Moscow, 1961.Google Scholar
5. Thomson, J. H. et al. Nature, 190, 519, 1961.Google Scholar
6. Maron, I. et al. Science, 134, 1419, 1961.Google Scholar
7. James, J. C, Ingalls, R. P. Astr. J., 69, 19, 1964.Google Scholar
8. Klemperer, W. K. et al. Astr. J., 69, 22, 1964.Google Scholar
9. Kotelnikov, V. A. et al. Dokl. Ak. N. SSSR, 147, 1320, 1962.Google Scholar
10. Carpenter, R. L., Goldstein, R. M. Science, 142, 381, 1963.Google Scholar
11. Kotelnikov, V. A. et al. Dokl. Ak. N. SSSR, 151, 811, 1963.Google Scholar
12. Goldstein, R. M., Gillmore, W. F. Science, 141, 1171, 1963.Google Scholar
13. Goldstein, R. M. Science, 144, 842, 1964.Google Scholar
14. Kotelnikov, V. A. et al. Soviet Phys. Dokl., 9, 250, 1964.Google Scholar
15. Rabe, E. Astr. J., 59, 409, 1954.Google Scholar
16. Pettengill, G. H. et al. Astr. J., 67, 181, 1962;Google Scholar
Smith, W. B. Astr. J., 68, 15, 1963.Google Scholar
17. Muhleman, D. O. et al. Astr. J., 67, 191, 1962.Google Scholar
18. Thomson, J. H. Quart. J. R. astr. Soc, 4, 347, 1963.Google Scholar
19. Kotelnikov, V. A. et al. Dokl. Ak. N. SSSR, 151, 532, 1963.Google Scholar
20. Duncombe, R. L. Astr. J., 61, 226, 1956.Google Scholar
21. Duncombe, R. L. Private communication.Google Scholar
22. Ash, M. E. MIT Lincoln Laboratory Technical Report. In preparation, 1964. Similar computer programs have also been developed at JPL (Muhleman, D. O. Private communication).Google Scholar
23. Duncombe, R. L. As quoted in Gravitation: An Introduction to Current Research. Ed. Witten, L., Wiley, , New York, p. 42, 1962.Google Scholar
24. Chazy, J. La Théorie de la Relativité et la Mécanique Céleste. Gauthier-Villars, Paris, p. 206, 1928.Google Scholar
25. Rzhiga, O. N. Paper presented at COSPAR, 1963.Google Scholar
26. Carpenter, R. L. Astr. J., 69, 2, 1964.Google Scholar
27. Goldstein, R. M. Astr. J., 69, 12, 1964.Google Scholar
28. Ponsonby, J. E. B. et al. Nature, 204, 63, 1964.Google Scholar