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长征四号乙运载火箭

長征四號B運載火箭由上海航天技术研究院負責研製,1989年2月開始研製。該火箭是在長征四號A火箭的基礎上研製的運載能力更大的火箭,主要用於發射太陽同步軌道的對地觀測應用衛星。火箭主要作了下列改進:
  • 加大了整流罩尺寸;
  • 調整了三子級儀器艙的高度,以適應衛星對對接尺寸的需要;
  • 控制系統用的程式配電器改用電子式,提高了發送程式指令的時間精度;
  • 控制、遙測、跟蹤測量、安全自毀系統的儀器以及電纜網均實施小型化與輕量化,以減小其質量,提高運載能力;
  • 二子級增加推進劑利用系統,提高了運載能力,同時發動機則採用高空噴管方案,提高了比沖的性能;
  • 三子級設置了剩餘推進劑排放系統。
1999年5月10日長征四號B火箭在太原衛星發射中心首次發射。2013年12月9日中国在太原卫星发射中心用长征四号乙运载火箭发射中国与巴西合作研制的资源一号03星,火箭飞行过程中发生故障,卫星未能进入预定轨道,发射失败

 The CBERS 3 satellite launched at 0326 GMT Monday (9:26 p.m. EST Sunday) on a Chinese Long March 4B rocket from the Taiyuan space center in northern China's Shanxi province, where it was 11:26 a.m. local time.
The 15-story rocket was supposed to put the 2.3-ton spacecraft into orbit about 12 minutes later, but something went wrong. It was not clear early Monday when the rocket ran into trouble, but Chinese and Brazilian news reports said the satellite did not enter orbit.
The mishap marks the first launch failure in 20 flights of the Long March 4B rocket since 1999. The last time any Long March rocket malfunctioned was in August 2011, when a Long March 2C launcher faltered while carrying a Shijian military satellite.
China typically uses the three-stage Long March 4B booster to place civilian and military satellites into polar orbits from the Taiyuan launching center.
Brazil's National Institute for Space Research, known by the acronym INPE, initially issued a statement overnight heralding a successful launch for CBERS 3, but subsequent reports published on the Chinese news website Sina.com and by the Brazilian newspaper Folha de S. Paulo said the launch failed and the CBERS 3 satellite did not go into orbit.
After inquiries into the outcome of the launch, an INPE spokesperson confirmed the launch failure early Monday.
"There was a malfunction of the launch vehicle during flight, and consequently the satellite was not positioned in orbit," INPE said in a statement. "Preliminary evaluations suggest that the CBERS 3 has returned to the planet.
"Chinese engineers responsible for the construction of the launch vehicle are evaluating the causes of the problem," the statement said.
China's state-run Xinhua news agency released a three-paragraph story on the rocket malfunction. Engineers are analyzing the cause of the failure, Xinhua reported.
"The data obtained show that the subsystems of CBERS 3 functioned normally during the [launch]," INPE said.

 The compact car-sized CBERS 3 satellite was supposed to enter a 483-mile-high polar orbit with an inclination of 98.5 degrees.
Brazilian news reports said the satellite cost $250 million, with Brazil and China equally sharing the investment. Folha de S. Paulo reported the launch cost $15 million.
CBERS 3 was the fourth China-Brazil Earth Resources Satellite launched since 1999. Its three predecessors are no longer functioning, forcing Brazil to purchase Earth observation data from other countries.
China and Brazil started cooperating in Earth observation programs in 1988.
CBERS 3 was built by the China Academy of Space Technology, with two of its imaging instruments coming from Brazil and two from China. It was designed for a three-year lifetime.
The satellite's cameras were supposed to collect black-and-white imagery with a top resolution of about 5 meters, or about 16 feet. Its sensors included thermal and infrared imagers capable of distinguishing different types of vegetation and locations where water is stored and consumed.
According to INPE's website, Brazil uses CBERS data to monitor wildfires and deforestation in the Amazon rainforest, observe crop yields and trends in land use, manage water resources, and study urban development.
Like its Landsat counterpart in the United States, the CBERS project distributes imagery for free on the Internet. INPE says it provides about 700 images per day from the CBERS data catalog to hundreds of environmental institutions around the world.
China and Brazil are working on their next joint satellite - CBERS 4 - for launch in 2015. After Monday's launch failure, officials agreed to start discussions in anticipation of the launch of CBERS 4, according to INPE's statement.

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