NANJING -- China's upgraded tracking vessel Yuanwang 6 is sailing to the Pacific Ocean from a port in East China's Jiangsu province Wednesday for multiple maritime missions of spacecraft monitoring.

The vessel's last voyage to the Pacific was 22 months ago.

Yuanwang-6, commissioned in April 2008, represents the third generation of the country's Yuanwang space-tracking ships. After completing a monitoring mission of the Chang'e 4 relay satellite in July 2018, the vessel has undergone maintenance and maritime calibration tests.

Yang Bianjiao, captain of Yuanwang 6, said the upcoming mission will test the vessel's new equipment and improvement in measuring and controlling operation, laying foundations for future missions including the Mars exploration and Chang'e 5 lunar probe launch.

Crew members have examined facilities and conducted a series of training programs and tests before the voyage to improve their emergency response capabilities.