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The author:(作者)hpmailerpublished in(发表于) 2013/12/2 10:12:26 Chang， third from flying to the Moon trip 13 days _ Sina news
Launched today at 1:30 A.M., until the Rainbow Bay area a soft landing on the lunar surface to become immortal, the third to go through a 13-day trip. This was published by the National Defense Science and Industry Council the information revealed in a video.
On this trip, Professor, school of Earth and space sciences, Peking University, China Jiao weixin, Deputy Director of the Institute of space sciences space exploration professionals Committee told Beijing Youth daily interview was interpreted.
First stage: 5 days
2nd, long third away 23 b rocket carrying Chang launch third satellite at the Xichang satellite launch Center, fed directly by the rocket according to perigee cent, apogee of about 200-kilometer about the earth-moon transfer orbit. Flight time is approximately 5 days to 2 to 3 times in the course of the mid-course corrections.
Expert explanation: Chang, third lunar flight this time slightly longer than the Moon, second. Because this is a longer flight time and flight route, but more to save energy, "Hoemann tracks".
Phase II: circular orbit around the Moon for 4 days
In recent months, after braking, to 100x100 km lunar orbit, after running for about 4 days, snagged and orbit.
Expert explanation: Chang-4 days before the third lunar, in addition to scientific observations of the Moon, but also to take advantage of the opportunity to obtain more data, to prepare for the finalization of the landing site.
Phase III: elliptic orbit around the Moon for 4 days
Orbit into the elliptical orbits of 100x15 km, running about 4 days later, fell from power in recent months point in around 15-kilometer.
Expert explanation: oval track in recent months is 15-kilometer, and just over the Rainbow Bay area to become immortal, the third at 4 days after around a month can be more accurately to the book investigates the landing measuring to ensure landing without craters or big stones. If round the Moon is 4 days before the Moon "have a look" around the Moon is 4 days after "look".
Phase IV: down 720 seconds after landing
Powered down for 720 seconds. In the meantime, Chang, third with microwave sensors, laser range sensor for months ranging speed; use optical imaging sensors in close proximity to thick and obstacle avoidance; hover using laser imaging sensors in three essential obstacle avoidance, achieving security zone to a soft landing.
Expert translation: at this stage to become immortal, the third mission has entered the most crucial phase, and most aspect of the stage. This manifested in a 12-minute technical content is very high. 720 seconds are calculated through fine--declining Chang, third is not perpendicular to the surface, are related to the lunar surface at an angle, and "side of the left side look very carefully" because of 15-kilometer it is relatively far away. In 12 minutes if you find the lunar surface there are obstacles, such as slope and steep, or crater, large stones and so on, you'll make it in time to avoid it. And down at a certain height to hover for some time, last surveyed in a stationary State ground obstacles.
Fifth stage: "Moon" moon landing
After landing, choose complete releases Lunar Rover, Lander established working condition. The "rabbit" on the Rovers moved to transfer authority, along with the transfer mechanism in place, and leave the transfer agency, arrived at the moon.
Expert explanation: this is the only stage did not disclose a specific time, but not very long. Now can be sure of is that flight control center in Beijing in the first returned in time to see Chang, third screen.
Sixth stage: months 3 months to 1 year
Since then, during the months of daylight, the lander carried out in situ for scientific exploration, Lunar Rover patrol inspections carried out by. Moonlight both power outages during hibernation, rely on isotope heat source to keep the temperature Regulator. After you spend the night, through light self-awakening, continued the mission. The working hours of the lander in the month was a year, the Moon is three months.
Expert translation: Lunar Rover design time is three months, but as long as it doesn't actually happen technical failure, month or fall into a deep pit, is expected to be able to work longer than three months.
Text/reporter Porto Recanati
Secret · detector
Chang the third is how to design?
Chang the third probe, is China's first "leg" of the spacecraft. The "three girls" is how to design? Reporters interviewed the relevant experts of the China Aerospace Science and Technology Corporation.
Configuration design of four-legged six rounds of both Moon and action
According to reports, the "three girls" has four legs six wheels. Designer Yang Jianzhong, Director of the aerospace science and technology group introduced, that combination configuration, are determined by the characteristics of its mandate. Chang, third has two main tasks: one is to achieve Lunar soft landing, the second is the implementation of moon patrol reconnaissance. This requires both falling on the lunar surface, can independently animated.
Fall months ago, toured as a payload is mounted on the lander itself does not work. During the entire flight, power dropped and the implementation of a soft landing in the early, are done by the lander. After months, both compatible with visiting collector on the surface, becoming two separate detectors, in months of efforts to detect their mandates.
Lander contains 11 sub-system, one of the most distinctive is the landing cushion system, embodied in the four "Chinese leg" shape. Chang, third landing mission, leg can guarantee the stability of landing.
Contains 8 system for inspection, one of the most distinctive are the move system. From the appearance point of view, is visited by 6 wheels. Visiting Vice President of China Aerospace Science and technology group designers introduce Jia Yang, stone-wheel can avoid bad control, easy card shortcomings.
In addition, due to the weight of the detector limit to become immortal, the third must be "downsizing", integrated, compact design, and also to ensure the reliability of the system. The only way to guarantee that it is a robust probe.
Chang Moon path path design like never before
Chang, third you want to power down in recent months, some 15 kilometres, this is a parabolic line decreases. Probes from the 1.7 km/s relative velocity gradually reduced to 0, the process is driven by detector independently to complete, almost zero possibility of manual intervention. When from the lunar surface 100 meters, detectors to hover, photographing the lunar surface, avoiding obstacles, searching for landing sites.
Engineers on the ground, the process for the first time, there are two major risks. Is the key equipment that is newly developed, including GNC systems (guidance, navigation and control systems), and China's first new space for 7,500 n variable thrust engine. Second soft landing the topography of the area there was a degree of uncertainty.
Probe after Lunar soft landing, the lander separated and inspections should be carried out, achieving shooting each other. Lander largely fixed in one place, visit requires from the Lander's "walk" down, Moon patrol reconnaissance. Path of the lunar surface, but also to "tele-operated" and "patrol independently control the" combination of technical means.
In addition to ground remote-operation, inspections can also use computers, processes the images, identify obstacles, plan out relatively close to local path, control the movement of their own. At this time, visiting is an autonomous mobile robot.
Function design of cold "quilts" or "stove"
Unlike Earth, the surface of the Moon larger temperature difference between day and night, at the high temperature to 120 degrees Celsius, temperature is low at lingxia180sheshidu. Also, alternating day and night of the Moon cycle is longer, which gives "three girls" brings a great deal of difficulty to the lunar surface survival.
Lander of the China Aerospace Science and technology group of thermal control subsystem designer Liu Zijun, Director of "tuck", "make" and "open air" and other familiar concept explanation of control design. Chang, third, there is a multi-layer insulation components, known as "blanket", bi-directional, and external high-temperature heat from inside, cold outside when heat from leaking.
Cold "three girls" or "stove". "Stove" mainly isotope nuclear sources, it can radiate. Designers have designed the gravity-driven two fluid circuits, heat when you need to import the cabin, cut heat transfer when not needed.
To the months of daylight, Rainbow Bay temperature quickly rise to 90 degrees Celsius, on the Moon's surface, cooling only heat radiation. Designers are detectors designed several thermal, thermal escape device.
With these means and methods, "three girls" could properly protect themselves and survive on the surface, which can be used to carry scientific payloads for the work. Text/Xinhua reporters Wang Min
Revealing · rockets
Up to three for Chang to make innovation?
Long March series rocket carries the most powerful "Hercules"-how long triethyl reinforced rocket is slimming exercise lifts "the moon lady"? Chang, third Commander and Chief Designer of the launch vehicle system and rocket experts resolved for you. "Researchers of rocket launched six special technology to ensure lift baochange ' perfect Moon '. Tower "third rocket system Commander Cen Zheng said.
Finely crafted "thin"
"' Trek ' 3,780 kilograms of ' goddess ' accurately to the apogee of 380,000 kilometers of the earth-moon transfer orbit, long March b rockets, third capacity limit is reached. Longer takeoff thrust was 600 tons of triethyl-enhanced, to increase the load carrying capacity, the rockets must ' slim down '. "Chang the third probe, Commander-in-Chief of the rocket system Cen Zheng said.
Aerospace Science and Technology Corporation, China Academy of launch vehicle technology for up to three children tailored three hydrogen and oxygen tanks weight reduction programme. Tank weight, just like "fat", carrying fuel, just like the body of energy. In the case of constant energy, "fat" fewer, the bigger the carrying capacity. To this end, the Academy of launch vehicle technology with new siding mechanical milling for the first time. Milled siding this way smooth, high accuracy, thickness tolerance within 0.1 mm. This uncompromising, makes tank successfully lose weight 50 kg.
Gold Medal momentum "stronger together"
"In the face of China's first direct detection of extraterrestrial objects in aircraft's new mission, six tries their best to build highly reliable, high performance ' Chang ' e third ' flying power, rocket-powered ' pushing sperm, flying steady '. "Rocket engine expert, Academy of China Aerospace Science and Technology Corporation, six Tan Yonghua said.
From Shenzhou first Shenzhou tenth from Chang-Chang, first, third, China Aerospace stretching the limits again and again to create new heights. Design and development of aerospace engine industry faring six homes has won "China Gold power" in the world. This to launch up to three rockets all engines He Change the third spacecraft propulsion subsystem, developed by six homes.
F rocket launch two Shenzhou tenth compared to three enhanced added a third child. This stage consists of two hydrogen-oxygen engine, and composed of several attitude control engine. "Hydrogen-oxygen rocket engine using liquid hydrogen and liquid oxygen at low temperature by high energy propellant pump pressure type gas generator power cycle, gas-line twin-turbo-pump system, with bi-directional swing, high altitude twice to start. Chang, third moon trip more robust. "Six Vice President Liu Zhirang said.
In addition, researchers on the three primary and secondary-b launch vehicle and a series of reliability growth booster engine improvements.
Text/Xinhua, Yu Xiaojie Wu Jingjing fields
(Original title: from flying to the Moon Goddess tour 13 days)
从今天凌晨1时30分升空，直到在月球表面虹湾区软着陆，嫦娥三号要经历13天的旅程。这是国防科工局公布的一段视频中透露的信息。
就这段旅行，北京大学地球与空间科学学院教授、中国空间科学学会空间探测专业委员会副主任焦维新接受北京青年报记者采访时作了解读。
第一阶段：飞行5天
2日凌晨1时30分，长征三号乙遥二十三运载火箭搭载嫦娥三号卫星在西昌卫星发射中心发射，由运载火箭直接送入据近地点约200千米、远地点约38万千米的地月转移轨道。飞行时间约为5天，其间进行2至3次中途修正。
专家解读：嫦娥三号的这次奔月飞行比嫦娥二号略长一点。因为这次采用的是飞行时间和飞行路线较长，但比较节省能量的“霍曼轨道”。
第二阶段：圆轨道绕月4天
近月制动后，进入100×100千米的环月圆轨道，运行约4天后，择机变轨。
专家解读：嫦娥三号的前4天绕月，除了可以对月球进行科学观测，更是要利用这个机会获取更多数据，为最后确定着陆点做准备。
第三阶段：椭圆轨道绕月4天
变轨后进入100×15千米的椭圆轨道，运行约4天后，从高度约15千米的近月点开始动力下降。
专家解读：椭圆轨道的近月点是15千米，而且正好在虹湾地区上空，嫦娥三号在后4天的绕月中可以更加准确地对预订着陆点进行勘察测量，以保证着陆点没有月坑或大的石头。如果说前4天绕月是对月球“看一看”，后4天绕月就是“仔细看”。
第四阶段：下降720秒后着陆
动力下降的时间为720秒。其间，嫦娥三号将利用微波测距敏感器、激光测距敏感器进行对月测距测速；利用光学成像敏感器在接近段进行粗避障；利用激光三位成像敏感器在悬停段进行精避障，实现安全区软着陆。
专家解读：到这个阶段，嫦娥三号任务就进入了最关键阶段，也是最有看点的阶段。这短短的12分钟里体现出来的技术含量是非常高的。720秒是经过精细计算的——嫦娥三号不是垂直向月面下降，是与月面成一定角度下降，并且“一边落一边仔细看”，因为15千米的距离还是比较远的。在这12分钟内如果发现月面还有障碍，比如坡度比较陡，或有陨石坑、大石头等等，还来得及及时躲避。而且下降过程中在一定高度还要悬停一段时间，在静止的状态下最后勘测地面障碍。
第五阶段：“玉兔”登月
着陆后，择机完成月球车释放，着陆器建立工作状态。“玉兔号”月球车移动到转移机构上，随转移机构运动到位，并驶离转移机构，抵达月面。
专家解读：这是唯一没有公布具体时间的阶段，但估计时间不会很长。现在能确定的是，北京飞控中心能够在第一时间看到嫦娥三号传回的画面。
第六阶段：月面工作3个月到1年
此后，在月昼期间，着陆器在原地进行科学探测，月球车进行巡视勘察。月夜期间二者都断电休眠，依靠同位素热源保持整器的温度。度过月夜后，通过光照自主唤醒，继续实施探测任务。着陆器在月面的工作时间是一年，月球车是三个月。
专家解读：虽然月球车的设计工作时间是三个月，但实际上只要它不发生技术故障，或掉进深的月坑里，预计能工作的时间会超过三个月。
文/本报记者 雷嘉
揭秘·探测器
嫦娥三号是如何设计出来的？
嫦娥三号探测器，是我国第一个“有腿”的航天器。这位“三姑娘”是如何设计出来的？记者采访了中国航天科技集团的有关专家。
构型设计 四腿六轮既能落月又能行动
据介绍，“三姑娘”有四条腿六个轮子。航天科技集团主任设计师杨建中介绍，这样的组合构型，是由其任务特点决定的。嫦娥三号任务主要有两个：一是实现月面软着陆，二是实施月面巡视勘察。这需要它既能落到月面上，还能自主动起来。
落月之前，巡视器作为一个载荷被安装在着陆器上，本身并不工作。整个前期飞行、动力下降以及实施软着陆过程，都是由着陆器完成的。到月面后，二者互相配合，将巡视器释放到月面上，成为两个独立的探测器，各自在月面开展探测任务。
着陆器包含11个分系统，其中最有特色的当属着陆缓冲分系统，又集中体现在四条“中国腿”的外形上。就嫦娥三号软着陆任务来讲，腿式能保证着陆的稳定性。
巡视器包含8个分系统，其中最有特色的当属移动分系统。从外形上看，就是巡视器的6个轮子。中国航天科技集团巡视器副总设计师贾阳介绍，轮式能避免不好控制、遇石块容易被卡的缺点。
此外，由于探测器的重量限制，嫦娥三号必须“瘦身”，进行集成化、小型化设计，还必须保证系统的可靠性。只有这样，才能保证它是一个健壮的探测器。
路径设计 嫦娥落月路径前所未有
嫦娥三号要在近月点15公里处进行动力下降，这是以抛物线下降。探测器的相对速度要从1.7公里/秒逐渐减为0，过程主要靠探测器自主来完成，人工干预的可能性几乎为零。距月面100米处时，探测器还要悬停，对月面进行拍照，避开障碍物，寻找着陆点。
对于地面工程人员来说，这一过程尚属首次，存在两大风险。一是关键设备都是新研制的，包括GNC系统(制导、导航与控制系统)和我国首台全新的7500牛变推力空间发动机。二是软着陆区域的地形地貌存在一定程度的不确定性。
等到探测器在月面实现软着陆后，着陆器和巡视器还要进行分离，实现互相拍摄。着陆器基本固定在一个位置，巡视器则需要从着陆器上“走”下来，进行月面巡视勘察。在月面路径中，还涉及到“地面遥操作”和“巡视器自主控制”相结合的技术手段。
除了地面遥操作外，巡视器也可以利用计算机，对图像进行处理、识别障碍，规划出相对较近的局部路径，控制自身的移动。这时候，巡视器就是一个自主移动的机器人了。
功能设计 遇冷有“被子”还能“生炉子”
不同于地球，月球表面昼夜温差较大，温度高时有120摄氏度，温度低时在零下180摄氏度。而且，月球的昼夜交替周期也较长，这给“三姑娘”的月面生存带来了很大的难度。
中国航天科技集团着陆器热控分系统主任设计师刘自军用“盖被子”“生炉子”和“开空调”等熟知的概念解释热控设计。嫦娥三号上有一个多层隔热组件，也就是所谓的“被子”，可以双向隔热，外部高温时候热量不能往里传，外部寒冷时候里面热量不能往外漏。
寒冷时“三姑娘”还得“生炉子”。“炉子”主要是同位素核源，它能够持续放热。设计师们还设计了重力驱动的两项流体回路，在需要的时候将热量导入舱内，不需要的时候切断传热途径。
到了月昼时，虹湾温度迅速升高至90摄氏度，在月球表面，散热的方式只有热辐射。设计师们在探测器上精心设计了几个散热面，可以把设备发出的热量散出去。
有了这些手段和方法，“三姑娘”便能很好地保护自我，在月面上生存下来，从而用携带的科学载荷进行工作。文/新华社记者 王敏
揭秘·火箭
长三乙为嫦娥做出什么创新？
长征系列火箭中运载能力最强的“大力士”——长三乙增强型火箭是如何瘦身健体托举“嫦娥”的？嫦娥三号运载火箭系统总指挥、总设计师和火箭专家们为您解析。“科研人员对火箭开展了六大专项技术攻关，确保托举保嫦娥‘完美落月’。”嫦娥三号火箭系统总指挥岑拯说。
精雕细琢“瘦”下去
“要‘长途跋涉’把3780公斤的‘嫦娥’精准地送入远地点38万公里的地月转移轨道，已达到长征三号乙火箭的运载能力极限。长三乙增强型的起飞推力是600吨，要提高载荷能力，火箭自身必须‘瘦身’。”嫦娥三号探测器火箭系统总指挥岑拯说。
中国航天科技集团公司运载火箭技术研究院为长三乙量身制定了三子级氢氧贮箱减重方案。贮箱的自重就像“脂肪”，承载的燃料就像身体蕴含的能量。在能量不变的情况下，“脂肪”越少，运载的能力也就越大。为此，运载火箭技术研究院首次采用新型机械壁板铣的方式。这种方法铣出来的壁板光滑、精度高、厚度误差在0.1毫米之内。正是这样的精雕细琢，使得贮箱成功减重50公斤。
金牌动力“强起来”
“面对中国飞行器首次对地外天体进行直接探测的全新使命，六院倾力打造高可靠、高性能‘嫦娥三号’飞天动力，使火箭动力系统‘推得精，飞得稳’。”火箭发动机专家、中国航天科技集团公司六院院长谭永华说。
从神舟一号到神舟十号，从嫦娥一号到嫦娥三号，中国航天一次又一次突破极限创造新高度。以设计研制航天发动机为主业的航天六院赢得了“中国金牌动力”的美誉。此次承担发射任务的长三乙火箭所有发动机和嫦娥三号探测器推进分系统，均由六院研制。
与发射神舟十号用的长二F火箭相比，长三乙增强型增加了一个三子级。这级火箭由两台氢氧发动机和若干台姿控发动机组成。“氢氧发动机使用液氢、液氧低温高能推进剂，采用泵压式燃气发生器动力循环，燃气串联双涡轮泵系统，具有双向摇摆，高空两次启动能力。它使嫦娥三号奔月之旅更加稳健。”六院副院长刘志让说。
此外，科研人员对长三乙运载火箭一、二级及助推器发动机进行了一系列可靠性增长改进。
文/新华社记者 余晓洁 吴晶晶 田野
(原标题：从飞天到落月 嫦娥需旅行13天)
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