The China National Space Administration launched another trio of satellites into orbit late Friday (March 12), adding to its network of spy satellites observing regions nearby Chinese territory.
The fresh set of Yaogan 31-series satellites launched at 9:19 p.m. EST Friday (0219 GMT Saturday or 10:39 a.m. local time) from the Jiuquan Satellite Launch Center in northwest China, near the Gobi desert, according to local reports.
A short report from Chinese state media outlet Xinhua (opens in new tab) said that the satellites deployed safely from the Long March-4C rocket that carried them to orbit. "The satellites will be used for electromagnetic environment surveys and other related technology tests," the report stated.
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While China hasn't said much about the purpose of these satellites, outside observers have said the Yaogan-31 series are for military purposes, picking up radio signals from foreign ships. The satellites include optical, radar and signal intelligence instruments on board, according to Spaceflight Now (opens in new tab).
"The Long March 4C deployed the Yaogan 31 trio in an orbit approximately 680 miles (1,100 kilometers) in altitude at an inclination of 63.4 degrees to the equator, according to publicly-available U.S. military satellite tracking data," Spaceflight Now added.
The orbits of the March 12 satellites appear to match two previous launches of Yaogan-31 satellites on Jan. 29 and Feb. 24, the report added. Another clutch of satellites launched successfully in April 2018. All of these satellites share a similar orbit, but the additional launches likely decrease the revisit times when a particular region is visible underneath the orbit of the satellites, which carries them over maritime regions such as the South Shetland Islands.
China has been busy with its space operations so far in 2021. We've seen the successful arrival of China's Tianwen-1 mission in Mars orbit and preparation for a Mars landing, the study of rocks on the lunar far side by the Yutu 2 rover and Chang'e 4 lander, and reports that the nation's first space station module will be launched fairly soon.
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