HELSINKI \u2014 China conducted a pair of launches Sunday, sending a second Yaogan-50 satellite into a highly retrograde orbit and completing a Kuaizhou-11 solid rocket rideshare mission.<\/p>\n
The country is once again accelerating its orbital launch activities following a near month-long hiatus for the Chinese New Year holidays and annual political sessions in Beijing, with the launches being the third and fourth since March 12.<\/p>\n
A Long March 6A rocket lifted off at 8:22 a.m. Eastern (1322 UTC) March 15 from Taiyuan Satellite Launch Center in north China. Airspace closure notices indicated the launch would be inserting a satellite into a highly retrograde orbit.<\/p>\n
The China Aerospace Science and Technology Corporation (CASC) announced<\/a> launch success, revealing the payload to be Yaogan-50 (02) satellite, joining the Yaogan-50 (01) satellite, launched in January<\/a>, in a highly retrograde orbit.\u00a0<\/p>\n That satellite initially entered 701 by 944-kilometer-altitude orbit with an inclination of 142 degrees\u2014a highly retrograde orbit, or opposite to the Earth\u2019s rotation\u2014before circularizing the orbit with an altitude of 952 kilometers. Such launches incur a performance penalty, as the launch vehicle must achieve orbital velocity without benefiting from Earth\u2019s rotational speed.<\/p>\n The mid-latitude orbit sees Yaogan-50 satellites pass over China and surrounding areas, with the retrograde orbit offering different groundtrack patterns for remote sensing than for prograde or sun-synchronous orbits. Later orbital data for Yaogan-50 (02) will reveal how it is orbiting in relation to the first satellite, and provide clues as to how many further satellites in the series.<\/p>\n While Yaogan-50 (01) was developed by the Shanghai Academy of Spaceflight Technology (SAST), the 02 satellite was developed by the China Academy of Space Technology (CAST), another major CASC subsidiary.<\/p>\n Yaogan satellites are described by China in generic, civilian terms. Yaogan-50 (02) is stated to be \u201cprimarily used for national land surveys, crop yield estimation, and disaster prevention and mitigation.\u201d Outside analysts assess Yaogan satellites to be part of China\u2019s intelligence, surveillance and reconnaissance assets, including spacecraft with synthetic aperture radar, optical and signals intelligence payloads.<\/p>\n The Long March 6A uses a kerolox core stage with solid side boosters, and is China\u2019s first liquid-solid combination launch vehicle. It was the 21st launch of the rocket, all of which have been successful. However, earlier launches saw a number of upper stages fragment in orbit, <\/a>creating debris.<\/p>\n Kuaizhou-11 launch\u00a0<\/p>\n China\u2019s second launch of the day came late on Sunday, with a Kuaizhou-11 solid rocket lifting off at 11:12 p.m. Eastern (0412 UTC, March 16) from Jiuquan Satellite Launch Center in northwest China.\u00a0<\/p>\n