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31.
F. Perotti A. Della Ventura G. Villa R.C. Butler G. Di Cocco R.E. Baker J.N. Carter A.J. Dean R.I. Hayles 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(4):117-119
During a balloon flight of the MISO telescope on 1980 May 17, the Crab Nebula and the Seyfert galaxy NGC 4151 were studied over the photon energy range 0.03 –16 MeV. The photon spectrum of the Crab Nebula was measured up to ～ 2 MeV. No gamma-ray emission from NGC 4151 was detected on this occasion. 相似文献
32.
Synchronization between an Earth station and a satellite in geostationary orbit can be accomplished by repeatedly transmitting sync burst signals and making small timing corrections. However, when a satellite is in an inclined nonsynchronous orbit, such as a navigation satellite, the problem is more complex due to the high relative velocity of the navigation satellite relative to the ground. One possible solution to the problem is examined by employing a satellite in geostationary orbit to communicate with the navigation satellite. It is shown that the uplink delay to the navigation satellite can be deduced to an accuracy of about 1 ns by making a single round trip transmission. 相似文献