Chinese Long March 4C rocket blasted off from the Taiyuan Satellite Launch Center on Thursday at 2:31 UTC, carrying the Yaogan 27 reconnaissance satellite to orbit. Chinese officials declared the launch a success about one hour after liftoff and orbital data confirms the identity of the satellite, that is kept secret by officials, as an optical reconnaissance spacecraft. No prior announcement was made regarding the launch, a pattern typical for Yaogan military satellite launches out of Taiyuan, located in the Shanxi Province.
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The Yaogan satellites either carry electro-optical imaging payloads, Synthetic Aperture Radar systems for all-weather imaging, or Electronic Intelligence payloads that are used to track activity on foreign territory including the tracking of ships across the oceans.
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As per the usual procedure, no information on the satellite's identity and orbit was provided by Chinese officials. Orbital data released through U.S. Space Surveillance shows the upper stage of the Long March 4C rocket to have reached an orbit of 1,065 by 1,205 Kilometers inclined 100.46 degrees.
This orbit matches that of the Yaogan 8, 15, 19 and 22 satellites, both in altitude and inclination, confirming that Yaogan 27 belongs to this group of 3rd generation electro-optical satellites. Another peculiarity of this satellite series is the use of a 3.35-meter payload fairing on the CZ-4C rocket which can be seen in the images released of this launch.