Shenzhou VII was on its twenty-eighth lap on September 27
The materials, calculations, and analysis are as follows:
1. Shenzhou VII Log
Beijing time, September 25-28, 2008, China successfully carried out the Shenzhou VII manned space flight.
Day 1 September 25
17:30: Astronauts' departure ceremony. Hu Jintao arrives at the astronauts' apartment, Ask the Sky Pavilion, to pay a cordial visit to the three astronauts, Zhai Zhigang, Liu Boming and Jing Haipeng, who are carrying out the mission, and to give them a strong welcome.
At around 18:00: the three astronauts arrived at the launch site. After confirming the technical status, the astronauts entered the Shenzhou-7 return capsule successively.
At about 18:35: Zhai Zhigang began to try to operate with the baton.
At about 2109 hours: Shenzhou VII launch went into 1-minute preparation, and the pendulum was fully opened.
21:09 hours: rocket ignition
21:10 hours: Shenzhou VII spacecraft lifted off
120th second of ignition, the rocket threw off the escape tower
159th second of ignition, the rocket first and second stage were separated successfully
200th second of ignition, the fairing was separated
500th second of ignition, second stage of the rocket was shut down
At 583 seconds of ignition, the spacecraft and the rocket were successfully separated
At about 2122 hours: the astronauts reported that the solar sail panels were unfolded and the body felt good.
21:30: Beijing Space Flight Control Center (BSFC) announced that the spacecraft had entered orbit normally.
At about 21:32: Chang Wanquan, commander-in-chief of the manned spaceflight project, announced the successful launch of the Shenzhou-7 spacecraft.
22:07: Shenzhou VII first in-orbit and out-of-cabin activities after liftoff space environment forecast: the space environment is calm and safe for the spacecraft's in-orbit operation.
23:19 hours: during the second lap of the Shenzhou VII spacecraft flight, astronaut Zhai Zhigang entered the orbital module for the first time from the return module of the spacecraft to carry out his work.
The second day, Sept. 26
4:04 p.m.: Shenzhou VII successfully changed orbit from an elliptical orbit to a near-circular orbit.
At about 10:20 a.m.: Astronauts began to assemble and test the extravehicular space suit.
12:0:36 to 8:46 p.m.: The Far Sight 6 ship accurately measures and controls the Shenzhou 7 spacecraft for the first time.
12:47 to 12:59 p.m.: The Shenzhou-7 spacecraft successfully penetrated the South Atlantic anomaly region.
21:47 hours: Assembly of both Flying Sky and Seahawk extravehicular spacesuits is completed
21:59 hours: Astronaut Zhai Zhigang talks to the flight control center.
At 22:25, the astronauts started to put on their personal equipment
At 23:36: Zhai Zhigang made his debut in space in the "Flying" extravehicular space suit developed by China.
Day 3, Sept. 27
At 13:57: The door of the return capsule closes and the astronauts begin preparations for leaving the capsule.
At about 1530 hours: the airtightness check of the extravehicular suit is normal, and the air pressure valve check is normal.
At 15:48: the charge center approved the orbital module to start pressure relief. The Shenzhou 7 orbital module started the first pressure relief.
At 14:00, the Shenzhou-7 Mission Command decided that Zhai Zhigang would be the astronaut to go out of the capsule, Liu Boming would support and cooperate with Zhai Zhigang in the orbital module, and Jing Haipeng would guard the return module.
16:17 hours: Shenzhou VII and Beijing Flight Control Center dialog, the spacecraft is running normally, the astronauts said they feel good, the astronauts oxygen and nitrogen end.
16:22 hours: astronauts put on extravehicular space suits.
16:24 hours: the important steps of the out-of-vehicle activities have been completed. The astronauts are ready for oxygen and nitrogen extraction and pressure relief.
16:26 hours: The orbital module started the second pressure relief, and the conditions for the astronauts to leave the module could be met when the air pressure inside the module dropped to 2 kPa.
16:39 hours: With the assistance and cooperation of Liu Boming and Jing Haipeng, Chinese astronaut Zhai Zhigang, a member of the Shenzhou-7 manned spacecraft, left the capsule successfully, carrying out China's first space exit activity.
At 1648 hours, Zhai Zhigang took his first step in space, and the first spacewalk by a Chinese began.
16:58: Beijing Space Flight Control Center issued a command: "Shenzhou 7, return to the orbital module".
16:59: Zhai Zhigang entered the orbital module and completely closed the door of the module, completing the spacewalk.
At about 15:01: The orbital module closes normally.
At 18:32: Hu Jintao, general secretary of the Central Committee, president of the People's Republic of China and chairman of the Central Military Commission, talks to the Shenzhou-7 astronauts.
19:24: Shenzhou VII successfully released the companion small satellite when the spacecraft flew to the 31st lap. This is the first time China has carried out a microsatellite companion flight test on a spacecraft.
20:16: The companion satellite completed its 20-minute photo-taking of Shenzhou-7, and the image was very clear.
21:45: The three astronauts on board Shenzhou-7 talk to their families from heaven and earth.
Day 4, Sept. 28
At about 11:06 a.m., the astronauts change into their cabin space suits.
At about 11:16 a.m., the three astronauts put on their in-cabin pressure suits and prepare for return. Return control data will be injected into the spacecraft.
At about 11:46 a.m., return control data was injected into the spacecraft.
At about 12:51 p.m., the door of Shenzhou 7's return capsule was closed, and Shenzhou 7's return phase began.
At about 15:26, the convoy tasked with search and rescue and recovery of the Shenzhou 7 spacecraft had departed from Ulanhua Town, Siziwangqi, and was on its way to the main landing site.
At 15:59, the main landing zone of Siziwangqi was put on high alert, with personnel on duty at all intersections, forbidding the entry of unrelated personnel and vehicles.
At 16:22, the ground search and rescue unit of the main landing site was moving towards the theoretical landing point of the airship.
At about 16:41, all measurement and control stations entered the 10-minute preparation for the return tracking of the Shenzhou-7 spacecraft.
At about 16:44, the Beijing Flight Control Center issued a command for the spacecraft to adjust its attitude. The spacecraft was positioned at one time.
At 16:51, the Beijing Flight Control Center announced that the spacecraft had entered the normal return track
At 17:02, all six search and rescue helicopters at the main landing site took off
At 17:06, the Beijing Aerospace Flight Control Center sent out a preview of the drop point to the various measurement and control points
At 17:12, the propulsion module and the return capsule flew away
At 17:17, the propulsion module and the return capsule flew away successfully.
At 17:17, the search and rescue helicopter arrived at the designated airspace and stood by
At 17:20, the Shenzhou 7 spacecraft flew into the airspace over China
At 17:20, the parachute of the return module opened
At 17:21, the spacecraft entered the black obstacle area, and the communication with the ground charge center was temporarily interrupted.
At 17:22, the spacecraft entered the main landing site
At 17:24, the spacecraft flew out of the black barrier area
At 17:25, search and rescue personnel in the helicopter held up a sign to indicate that the search and rescue began.
At about 17:25, the three astronauts informed the ground that they were feeling well
At about 17:36, Shenzhou VII completed its manned space mission, and the return capsule landed smoothly.
At 18:22, astronaut Zhai Zhigang successfully exited the capsule
At 18:23, astronauts Liu Boming and Jing Haipeng successfully exited the capsule
2.7 major systems
"1" Astronaut system
How are astronauts made?
Driving on Beijing's Badaling Expressway, turn west at the Bei'anhe exit, enter Beiqing Road, and after about 10 minutes of driving, you can see a silver metal sign on the left side of the road -- "China Beijing Space City." In this small village called Tangjialing, the aerospace city, which covers an area of about 3,500 acres, is heavily guarded. It is home to the China Astronaut Research and Training Center.
Shenzhou 7 astronauts Zhai Zhigang, Jing Haipeng, Liu Boming, China Astronaut Research and Training Center, the predecessor of the Institute of Cosmic Medicine and Engineering, founded on April 1, 1968, was renamed the China Astronaut Research and Training Center on September 30, 2005, and has become the world's third astronaut research and training center following the Gagarin Training Center in Russia and the Houston Space Center in the United States, known as the "Chinese astronauts research and training center". It is known as "the cradle of China's astronauts".
It is said that "Shenzhou" is summarizing the experience of selecting astronauts for "Shenzhou" and "Shenzhou" on the basis of the different division of labor of each astronaut in the crew and the scientific selection based on individual characteristics. The scientific selection was based on the individual characteristics of each astronaut, and fully complied with the principles of "science, fairness, objectivity and reasonableness". Space experts said, "God seven" astronauts are after five levels of screening to stand out, can be described as "two hundred miles a".
Shenzhou VII spacecraft 3 positive spaceman, including Zhai Zhigang, who was selected for the Shenzhou V and Shenzhou VI program, as well as two teammates who were also selected for Shenzhou VI, Liu Boming and Jing Haipeng. Zhai, 42, a native of Longjiang county in Qiqihar, Heilongjiang province, joined the air force in 1985 and has a safety record of more than 1,000 hours.
Fitian space suit made in China
Shenzhou VII prepared two sets of space suits, a set of Russia's Seahawk "Flying" extravehicular space suits, a set of China's independent research Fitian space suits. One is the Russian Seahawk "Feitian" space suit, and the other is the Feitian space suit independently researched by China. Feitian is our independent intellectual property rights, in the future astronauts out of the module may rely on our own space suit, rather than the Russian space suit. The spacesuits for this outward walk will be ours.
"2" Spaceship Application System
Spaceship Application System
Spaceship application system is a practical system, which is closely related to people's life and environment. The main task of the spaceship application system is to utilize the space experiment support capability of the manned spaceship to carry out earth observation, environmental monitoring, material science, life science, space astronomy, fluid science and other experiments, with hundreds of payloads and application equipments installed for a number of tasks, and the application of the spaceship in the test phase is of an experimental nature, with a wide range of experimental contents, and the results of the researches will be widely used in the development of medicine, food health care, The research results will be widely used in medicine development, food health care, prevention and treatment of difficult diseases, as well as in industry, agriculture and other industries. The manned spacecraft system adopts a three-compartment system consisting of an orbital module, a return module and a propulsion module, two pairs of solar cell sails and a lift-controlled return and dome parachute recovery program. The orbital module is located in the front of the spacecraft, equipped with the ship's subsystems for the spacecraft autonomous flight and stay in orbit to fly the equipment and payloads needed for the work.
Spaceship Application System Successfully Provides Meteorological Forecasting Services
Since 1992, the application system has completed the development of nearly 200 brand-new payloads, and more than 200 payloads participated in the launching of Shenzhou I and Shenzhou V. The payloads were used in the launching of Shenzhou I and Shenzhou V. The payloads were used in the launching of Shenzhou I and Shenzhou V, and were used in the launching of Shenzhou V. "More than 200 payloads have participated in the launches and in-orbit tests of the Shenzhou I to Shenzhou V spacecrafts respectively, and have achieved complete success; and all the systems of reception, pre-processing, monitoring and management of the Ground Application Center have been operated without failures. It has built a system integration test platform, a payload application center and a space environment forecasting center, conducted scientific research on 67 topics, created more than 100 new technologies and methods with independent intellectual property rights, and achieved fruitful scientific and technological results.
In terms of earth observation, the application system has successfully developed a number of advanced space remote sensors for China, such as the Moderate Resolution Imaging Spectrometer (MODIS), Multi-Modal Microwave Remote Sensors (MMMS), Earth Radiation Receiver and Spreader (ERS), Solar Ultraviolet Spectroscopic Monitor (SUVSM) and Solar Constant Monitor (SCM). Among them, the Shenzhou III Moderate Resolution Imaging Spectrometer (MODIS), the second MODIS to enter space following the launch of MODIS by the United States in 1999, has clear image quality and good spectral resolution, and the application departments have utilized these results to carry out experimental application studies, evaluating them as follows. "This marks a new stage in China's visible and near-infrared remote sensing, and China's visible and near-infrared remote sensing technology has crossed into the advanced ranks of the United States and the European *** bodies and other international organizations"; "Shenzhou" No. 4 multi-modal microwave remote sensors, which have achieved a large amount of scientific data with application value in orbit. The Shenzhou IV multimodal microwave remote sensor, operating in orbit, has obtained a large amount of scientific data with application value, and has succeeded in testing the microwave radiometer, microwave altimeter and microwave scatterometer in one go, which is an important breakthrough in China's space remote sensing technology; the precision orbiting of the spaceship in conjunction with the microwave altimeter has attained the highest precision in the global orbiting of China's low-orbiting space vehicles; the cirrus detector, with the capability of detecting large-area cirrus and thin cirrus, has exceeded the expected results and has been highly evaluated by users; and it has achieved, for the For the first time in China, the detection of the absolute amount of important parameters of the global environment was realized, and the systematic monitoring of the solar and terrestrial-gas ultraviolet, the solar constant and the state of the Earth's radiation balance was carried out, and the observation results reached the international level.
In the field of space life and microgravity science, a number of advanced experimental devices have been developed and dozens of space experiments have been conducted. Among them, the space experiments and theoretical studies on thermal capillary migration of microgravity droplets have reached the international leading level; the experiments on space cell culture, cell electrofusion, protein crystallization, space biological effects and space continuous free-flow electrophoresis, as well as the experiments on the growth of metal alloys, oxide crystals, and semiconductor opto-electronic materials under the conditions of microgravity in space have also achieved fruitful scientific results, and some of them have reached the international advanced level. The results have reached the international advanced level.
In the area of space astronomy, we have taken the lead in space observation of high-energy burst phenomena in the Universe and the Sun, and have achieved important results in γ-ray burst detection research. The success of the first phase of the space science program of the manned spaceflight project has enabled China to master important key technologies for space science experiments, and the level of space science experiments and exploration has crossed a new stage. The space environment monitoring and forecasting research arranged as a safety guarantee for manned spaceflight has acquired a large number of valuable space environment parameters of the spacecraft orbit, accurately forecasted meteor storm events and other disastrous space environment states that are hazardous to spacecraft launches, guaranteed the safety of the spacecraft and astronauts, and set up a space environment forecasting center, which has vigorously pushed forward the construction and development of China's space environment forecasting and guaranteeing system, while at the same time promotes the research level of related disciplines.
"3" Manned Spacecraft System
Manned Spacecraft Structure:
1, the orbital module is in the shape of a drum, which is the place where astronauts work, live and rest. The orbital module has adjusted the layout design of the cabin in order to install the application system equipment and the astronauts' food and drinking water devices. There is a hatch at the bottom of the rear end of the orbital module through which astronauts can enter the return module. The outer sides of the capsule are equipped with two solar battery wings like the wings of a bird, and the power required by the capsule is provided by these two battery wings.
2, the return capsule is the only section of a manned spacecraft that returns to Earth, and the astronauts are in the capsule when the spacecraft takes off, ascends to orbit and returns to land. The return module of Shenzhou VI is shaped like a clock, and its hatch is connected to the orbital module, through which the astronauts can enter the orbital module. The return module is the command and control center of the spacecraft, and astronauts' seats are installed in the module. The astronauts lie on the seats when the spacecraft takes off, ascends and returns to the ground. The return module is also installed in the flight astronauts need to monitor and operate the instrumentation, astronauts through these instruments can always judge, understand the work of the spacecraft, but also when necessary, artificial intervention in the spacecraft's systems and equipment work.
3, the shape of the propulsion module is also cylindrical, the module installed propulsion system engine and propellant, its mission is to provide the spacecraft with attitude high-speed and orbit maintenance of the power required, the spacecraft power supply, environmental control and communication systems, part of the equipment is also installed here. Two solar cell wings are also installed on both sides of the propulsion module's exterior to provide the spacecraft with the power it needs.
The orbital module and the return module of the manned spacecraft are sealed segments, with the cabin completely isolated from the outside world, and the environment and life-support systems installed inside will provide the astronauts with a comfortable living environment that is the same as that of the Earth. In addition, two parachutes, one main and one backup, have been installed for landing. Two circular windows have been opened on the side wall of the return module, one for the astronauts to observe the scene outside the window, and the other for the astronauts to operate an optical scope to observe the ground-piloted spacecraft.
"4" Launch Vehicle System
Shenzhou 7 will use a Long March 2F rocket to enter space. The rocket has now arrived at the launch base. The experts agreed that the function and performance of the rocket meet the overall engineering and mission requirements; the technical status of the product is under control, the development quality is good, and all the quality problems have been zeroed out or there is a clear conclusion that the mission will not be affected; the required reliability and safety project tests have been completed, and all the preparatory work meets the requirements of the guidelines for the factory release of products for human space flight.
Long March 2F rocket ready for launch
The main technical indicators of the Long March 2F launch vehicle:
The reliability of the rocket is 0.97, and the safety is 0.997: 0.97 reliability means that in 100 launches, there are only 3 times that the rocket may have a problem; and the safety of 0.997 means that in 1,000 launches, there are only 3 times that the rocket will endanger the lives of the astronauts. The safety of 0.997 means that out of 1000 times the rocket has a problem, 3 times may jeopardize the lives of the astronauts. This is the characteristic of manned rockets. General commercial rocket reliability is 0.91 to 0.93, there is no safety requirements.
The takeoff weight of the rocket is 479 tons: the rocket plus the spacecraft weighs about 44 tons, and the rest is liquid propellant. Thus, 90 percent of the rocket is liquid, which is greater than the water content of the human body. Water usually makes up 60 to 70 percent of the human body.
The spacecraft weighs more than 8 tons, or one sixty-two percent of the takeoff weight of the ship-rocket combination: to put one kilogram into orbit, it takes 62 kilograms of rocket. The Shenzhou VI spacecraft is an increase in weight over Shenzhou V, so the rocket that launches Shenzhou VI is also considerably heavier.
The rocket's core stage is 3.35 meters in diameter: the ancient Romans used a two-horse-drawn cart with wheels that wore two grooves in the stone road. As the wheels are not the same width, the road left a different width of the ditch. Later, they wanted to unify the wheelbase, the two side-by-side horse's ass as a standard, that is, 1.435 meters, and later the British repair railroads also set the railroad track gauge of 1.435 meters, and was followed by the countries. According to this gauge railroad, can transport the widest cargo for 3.72 meters, remove the carriages shell, only 3.35 meters. Therefore, the maximum diameter of rockets transported by standard railroads can only reach 3.35 meters.
The speed of the rocket at the point of entry into orbit is 7.5 kilometers per second: this speed is 22 times the speed of sound. We usually say "Ten Mile Street", refers to the distance from Jianguomen to Fuxingmen in Beijing, which is 6.7 kilometers long. A speed of 7.5 kilometers per second is equivalent to running from the east end of Chang'an Street to the west end in one second.
The rocket track is 200 kilometers near the earth and 350 kilometers far away: the radius of the earth is 6400 kilometers, and the distance between the rocket track and the earth is only a few tenths of the radius of the earth. If you stand outside the Earth and look at it, the spacecraft looks like it is flying close to the ground.
"5" Launch Site System
The basic tasks of the manned space launch site are to provide reproduction, assembly, testing and transportation facilities to meet the technical requirements for launch vehicles, spacecrafts and payloads; to provide pre-launch facilities for astronauts for life, medical supervision, medical insurance and training; to provide a full set of ground facilities for the launch of manned spacecrafts; and to organize, command and implement the testing, launching, and flight ascent section command and regulation of manned spacecrafts. and ascent section of the flight; organizing, directing and implementing emergency life-saving for the waiting section and ascent section; completing tracking measurement and safety control of the ascent section of the carrier rocket; providing relevant parameters and images for the Space Command and Control Center; and providing logistic services in the manned space launch area.
The Jiuquan launch site is built on an oasis in the Gobi Desert, with the mountains to the west and the river to the east, and is a piece of feng shui land personally selected by Marshal Nie Rongzhen in those years. So far, the mention of Jiuquan Satellite Launch Center, many people will be in Jiuquan. In fact, Jiuquan Launch Center is located in Inner Mongolia Autonomous Region, Alashan League, Ejinagi Banner, where there are 210 kilometers away from Jiuquan. At that time to "Jiuquan" named, one because at that time the countries missile satellite launch site name are avoiding the real address, the second is the launch site is located in the desert Gobi, it is difficult to choose a well-known name, and Jiuquan is the closest distance from the launch center, and in the history of the city is famous.
Jiuquan Satellite Launch Center, also known as the "Dongfeng Space City", is one of China's scientific satellites, technical test satellites and launch vehicle launch test base, is China's earliest and largest integrated missile and satellite launch center, is also China's only manned space launch site. With the changes in the mission, the launch site in the Shenzhou 7 mission not only to provide a test environment and technical support for the extravehicular space suit, but also to reformulate the testing and launching process, the extravehicular space suit and spacecraft joint test, extravehicular space suit and rocket joint test into the testing process.
6 Measurement, Control and Communication System
In the seven systems of Shenzhou, measurement, control and communication are crucial. To make an analogy, the spacecraft is like a kite, the measurement and control station and the oceanic measurement ships distributed in the three oceans are the threads holding the kite, and the control system on the ground is like the kite flyer. The level of the overall program design of the measurement, control and communication is directly related to the success or failure of the manned spaceflight project.
When the launching of the carrier rocket and the manned spacecraft fly into the sky as well as return, it is necessary to rely on the measurement and control communication system to keep the regular contact between heaven and earth, to complete the reception and processing of the telemetry parameters and TV images of the spacecraft, and to manage the measurement and control of the spacecraft's operation and the orbital module's stay in the orbit. This measurement and control communication system by the Beijing Aerospace Command and Control Center, land-based ground measurement and control stations and the sea ocean-going space survey fleet, the implementation of the spacecraft orbit measurement, remote control, telemetry, rocket safety control, astronauts escape control tasks.
China's spacecraft measurement and control system has formed a modern and comprehensive measurement and control network with the Xi'an Satellite Measurement and Control Center as the hub, and more than ten fixed stations, active measurement and control stations and the Fargo measurement ship as the backbone. In the manned spaceflight project, China's spacecraft measurement and control system uses a unified S-band system, sending or receiving telemetry and remote control signals, as well as voice and television signals through the same set of transmitter and antenna systems and receiving equipment. After the horn of moon exploration was blown, China's spaceflight measurement and control network and began to build the moon exploration measurement and control system, the second phase of the lunar exploration project will build a 35-meter aperture antenna deep-space measurement and control network, to improve China's deep-space measurement and control capabilities. In the future, China will also further strengthen international cooperation in the field of deep space measurement and control.
Mission:
The main purpose of this mission is to implement the first space outbound activity of China's astronauts, breakthroughs and mastery of outbound activity related technology, while carrying out satellite companion flight, satellite data relay and other space science and technology experiments. During the operation of the spacecraft, one astronaut with China's development of the "Flying" extravehicular space suit out of the cabin to carry out extravehicular activities, the recovery of test samples loaded in the cabin outside the device.
As planned, the Shenzhou spacecraft will be launched from the manned space launch site at China's Jiuquan Satellite Launch Center, operating in a near-circular orbit at an altitude of about 343 kilometers.
After the astronauts' exit activities are completed, the spacecraft will release a companion satellite. It will also carry out a data relay test for the "Sky Link 1" satellite.
Shenzhou 7 will return to the main landing site in central Inner Mongolia after completing its scheduled mission.
"7" landing site system
The spacecraft landing site system is a general term for the sub-systems responsible for capturing, tracking and measuring the re-entry trajectory of the spacecraft, searching for and recovering the return capsule, as well as carrying out the medical supervision, medical insurance, medical rescue and emergency evacuation of the astronauts after they leave the capsule.
The landing site is a newly added system in China's manned spaceflight project. The main task of the landing site system is: the spacecraft in space flight, from the return capsule re-entry into the atmosphere, the use of advanced radio measurement system, the target for capture, analysis and fall forecast, and then organize a rapid approach to the return capsule, and the return capsule to dispose of, and will be safely transported back to the base. The landing site system also includes: land and sea emergency return search and rescue sub-systems for the ascent section of the spacecraft, and specialized salvage boats and helicopters are deployed in the sea rescue area, equipped with equipment capable of salvaging the return capsule floating on the surface of the sea under complex sea conditions.
To make a spaceship flying at an altitude of more than 300 kilometers land accurately at a predetermined spot on the spinning earth is certainly not a simple matter, and it requires a variety of technological safeguards, with a very reliable control system, tracking system and a safe landing site system. In the former Soviet Union, there was a time when a spacecraft was returning, and because of a deviation in the control system, the spacecraft deviated more than 1,000 kilometers from its intended landing point. As a result, when the spacecraft landed at a certain height from the ground, after three cosmonauts were ejected from the spacecraft (at that time, they landed by parachute, not directly by the spacecraft), two of them landed on the ground, and one cosmonaut fell into the forest. Since the helicopters could not land in the forest, they had to be rescued only by sending special loggers to the scene in an emergency and creating a tarmac for the helicopters to land. The weather was so cold that the astronauts froze in the forest for a day and a night and almost froze to death. So in addition to the control and tracking technology of the spacecraft being very important, the selection and construction of the landing site for the spacecraft is also very delicate.
Of course, the landing site of the airship is not like the parachutist landing site, in a piece of flat ground to draw a circle, make a clear sign, the parachutist to control their own parachute, fall into the inside on the line. The choice of a landing site for a spacecraft is far from simple, and its construction is a very complex system.
Shenzhou 7 was launched successfully at 9:10 p.m. on Sept. 25th.
Shenzhou VII returned safely and the return capsule landed successfully at 17:37 p.m. on Sept. 28
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In conjunction with the materials:
1. September 25, 2008, 23:19 or so: during the second lap of the Shenzhou VII spacecraft flight, astronaut Zhai Zhigang for the first time from the return module of the spacecraft into the orbital module to carry out work.
2. September 27, 2008, 19:24: Shenzhou VII successfully released the companion mini-satellite during the 31st lap of the spacecraft's flight. This was the first time that China carried out a microsatellite companion flight test on a spacecraft.
The time from the 2nd lap performed to the 31st lap is (24 hours + 20 hours = 44 hours)
44 hours divided by 31-2 = 29 laps = 1.517 hours/lap
1.517*(28-2) = 39 hours
23:19 on Sept. 25, 2008 + 38 hours = September 2008 27th around 13:00
So according to the material and calculations: the astronauts were at the 28th lap on September 27, 2008
About 13:57: the door of the Return Module was closed, and the astronauts began to carry out the pre-departure preparations.