10.12.2021

A Long March-4B rocket carrying the Shijian-6 05 satellites blasts off from the Jiuquan Satellite Launch Center in northwest China, Dec. 10, 2021. China successfully sent a new group of satellites into space on Friday. The satellites, Shijian-6 05, will be used for space exploration and new technology test. (Photo by Wang Jiangbo/Xinhua)

A Long March-4B rocket on Friday morning successfully sent a new group of satellites into space, marking the 400th launch mission of the China-developed Long March carrier rocket series.

Since the first launch in 1970, the Long March carrier rocket series has carried out 92.1 percent of China's space launch mission, according to the China Aerospace Science and Technology Corporation (CASC), developer of the rocket series and also the leading force of the country's space industry.

Over the past 51 years, the Long March series has sent more than 700 spacecraft into space, said the CASC.

In the 400 launch missions by Long March rockets, the first three 100 launches were completed in 37 years, 7 and a half years, and around 4 years, respectively.

While the lastest 100 launch missions were carried out within only 33 months since March 2019.

Wu Yansheng, board chairman of the CASC, said that the high launch frequency of the Long March highlights China's enhanced space launch capacity and the self-reliant spirit of the country's aerospace workers.

China's first space station Tiangong's core module, Chang'e-5 lunar probe, Tianwen-1 Mars probe, Shenzhou manned spacecraft, Tianzhou cargo craft, BeiDou-3 navigation satellites, and multiple others, were all sent into space by the Long March rockets amid the latest 100 launch missions.

Meanwhile, the growing Long March series has been continuously providing new rocket members, such as the Long March-5B, Long March-7A, Long March-8, to better serve China's persistent space exploration. Enditem

Quelle: Xinhua

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Long March 4B with Shijian-6 Group 5 satellites launches successfully from Jiuquan

A Long March 4B reportedly carrying a pair of Chinese Shijian-6 Group 05 satellites has launched successfully from the Jiuquan Satellite Launch Center in China’s Inner Mongolia region. The launch took place at 00:11 UTC (08:11 Beijing time) on Friday, December 10, from Site 9401 (SLS-2).

Satellite launches from Jiuquan normally take place from this launch pad, using Long March 2, Long March 4, and Long March 11 launch vehicles. The nearby SLS-1 is the site used for Shenzhou crewed launches on Long March 2F rockets.

The Long March 4B, which made its first flight in 1999, has flown forty-five missions, with all but one being successful. It is a refinement of the Long March 4 with a restartable third stage, while the Long March 4 series is itself based on older ICBM technology. The Long March 4 series, also known as Chang Zheng 4, uses highly toxic nitrogen tetroxide and UDMH (unsymmetrical dimethylhydrazine) hypergolic propellants like other Long March rockets, as well as older rockets like the American Titan II ICBM used during the Cold War.

Long March 4B sheds its insulation as it lifts off from Jiuquan with Shijian-6 Group 05

The Chang Zheng 4B is a 44.1-meter tall and 3.35-meter wide rocket, equipped with three stages all using the aforementioned N2O4/UDMH fuel. The first stage is powered by four YF-21C engines, with the stage generating 2,961.6 kilonewtons (kN) of thrust.

The second stage is equipped with a single YF-24C engine with a thrust of 742.04 kN. The third stage is equipped with two YF-40 engines capable of 100.85 kN of thrust. The CZ-4B is capable of orbiting up to 4200 kg to low Earth orbit, 2800 kg to a sun-synchronous polar orbit, or 1500 kg to a geostationary transfer orbit. This performance is similar to some versions of the retired American Delta II launcher.

The carrier rocket is built by the state-owned Shanghai Academy of Spaceflight Technology, and the Shijian satellites are built by the Dongfanghong satellite company, a contractor for the China Aerospace Science and Technology state corporation. Past Shijian satellites reportedly used the CAST968 platform and featured two deployable solar arrays in addition to batteries.

The last Shijian-6 satellite, part of Group 04, was launched in 2010. Eight prior Shijian-6 (SJ-6) satellites were launched prior to today, always in pairs, and these satellites are publicly said to be technology satellites used to probe the space environment, including space radiation, in the sun-synchronous polar orbit inclined 97.7 degrees to the equator. These satellites were placed in 578 by 593 km or 593 by 602 km altitude orbits.

The previous Shijian-6 launch, Group 04 in October 2010, launches on a Long March 4B from the Taiyuan Satellite Launch Center

Today’s launch puts the number of Shijian-6 series satellites flown to ten, if prior practice was followed, with 11 years elapsing between the last Shijian-6 and this one. Airspace closures prior to the launch indicated that this flight would also take a sun-synchronous polar orbit path.

The SJ-6 series of satellites, either in addition to or in contrast with their publicly reported civilian use, is also believed to be capable of ELINT (electronic intelligence) and would be able to eavesdrop on communications anywhere in the globe from its sun-synchronous polar orbit. The Shijian-6 series of satellites is believed to be meant to listen in on naval communications traffic.

Today’s launch was the 49th of the year for China and the 400th Long March/Chang Zheng flight. For comparison, the 300th launch of the LM/CZ series happened in March 2019, which shows that the cadence of Chinese orbital launches is rapidly increasing.

Quelle: NS