Chang'e II was successfully launched to achieve zero window

The so-called "zero window", referring to the pre-computed emission time, quite true to the rocket blasted off, does not allow any delay and change. This is directly related to the final if she has excess fuel to complete the task of the Moon impact.

Yesterday, 18:59:57, in the best "launch window", carrying "Chang'e II" satellite "Long March III C" carrier rocket from the Xichang Satellite Launch Base launched, accurate orbit an hour later, get fired success. This also marks the second phase of China's lunar exploration program kicked off.

Satellite "eye" 10 times

"Chang'e II" is China's first two independently developed lunar exploration satellite, the main task is to "Chang'e III" to achieve a soft landing of the lunar surface to carry out some key technical test, and to continue scientific explorations and studies of the moon. The launch is the "Long March III C" first lunar probe satellite launch missions responsible, but also China's "Long March" carrier rockets of the first 131 space flight.

In the sporadic rain in about 25 minutes after takeoff, the rocket to launch satellites into 200 km perigee and an apogee altitude of about 380,000 km of earth-moon transfer orbit. This indicates that China successfully penetrated the direct earth-moon transfer orbit launch technology. This technology breakthrough for the "Chang'e II" paved a "fast path" Ben month longer than "Chang'e I" by 7 days.

Ben takes about 112 hours on the flight, followed by 3 times in recent months after the brake, the satellite will be to establish a circular orbit 100 km away from the moon. In this than the "Chang'e I" work the low orbit altitude of 100 kilometers, the satellite carrying the payload on the 7, will help "Chang'e II" three-dimensional images to achieve access to the lunar surface, probe the lunar material composition, detection of lunar soil characteristics, detecting space in recent months on the environment with the 4 major scientific objectives. Among them, the newly developed CCD camera able to image resolution from the "Chang'e One" in the 120 meters be increased to better than 10 meters.

Wu Weiren lunar exploration project architect, said, "the satellite fly faster, more recently from the moon, 'see' a more precise." Period in orbit, the satellite will be reduced to 15 km altitude, the "Chang'e three No "alternative landing zone to shoot. The success of the image returned will be the "Chang'e II" mission, an important indicator of successful completion.

As a "soft landing" lay the foundation

"Chang'e II" mission total funding of approximately 900 million yuan investment, the satellite is in orbit design life of six months. The satellite's "fate," said Wu Weiren, sangrakwol, fly farther, or fly back to Earth orbit stars, you need some time in orbit to a decision.

"If" Chang'e I "opened a deep space exploration," Chang'e II "is for 'soft landing' and beyond lay the foundation for deep space exploration activities." Wuwei Ren said.

China's lunar exploration project is divided into three stages. Following the "Chang'e One" complete with "around" as the goal of a mission, "Chang'e II", "III", "IV" will constitute a "down" as the goal of the Phase II project. Wu Weiren, at present, "Chang III" and "IV" prototype being developed, focusing on the "back" of the three works have been completed demonstration program, "As for manned lunar landing, there is no specific timetable for China."


18:45 launched into 15 minutes for procedures;

18:51 engineers full withdrawal, the rocket finished filling;

18:58 preparatory procedure launched into 1 minute;


18:59 launch time;

19:01 booster separation, primary and secondary separation;

19:04 parabolic fairing, two separate three-stage rocket;


19:25 star separated from the rocket, the satellite began to orbit;

Expand the satellite solar panels 19:32;

19:39 satellites into the earth-moon transfer orbit;

Establishment of the satellite normal cruising attitude 19:40;

19:55 precise orbit, launching the successful completion of the task.

■ Watch

Chang'e "sister" the most punctual

Following the "Chang'e" after another to achieve "zero window" launch

Liquid hydrogen filling carefully Scene 1

II hillside behind the launch station, less than 1,000 meters from the rocket, fired station on the II is about to launch "Chang'e II" satellite.

Yesterday afternoon, 16, 97 meters high and weighs 4,600 tons of active service tower has been opened to the floor the other end of the launch site, launch tower on the "Long March III C" surrounded by rockets in the rotating platform, the quiet standing with. Cryogenic propellant filling in progress on the launch site, operator who complete each operation carefully. Liquid hydrogen filling of the entire pre-launch preparations for the most critical and most dangerous of a job. Testing has been done in a closed environment, the size of a grain of corn from the one-meter high metal impact force at the drop can be caused by liquid hydrogen explosion.

Measurement made in the remote control command of the hall floor, electrical measurement, telemetry, external measurement systems such as technical staff, are on rockets and satellites make a final test checks; the big screen, all kinds of data, charts, change frequently, scheduling password sound come .

Scene 2 Fat Controller button is pressed

"One hour to prepare!" 01 Yanli Qing commanders issued a password. "Woo -" shrill sirens suddenly sounded, the first group of technical staff began to evacuate the tower, into the nearby cave. Countdown to 40 minutes, slowly rotating platform on the tower open, supports the weight of "Chang'e II" satellite completely exposed in front of the rocket. "30 minutes to prepare!" Withdrawal of the second batch of technicians. "15 minutes to prepare!" The last batch of technical personnel evacuated.

Liquid oxygen, liquid hydrogen additional start before the shooting, saw the rocket transpiration fog shrouded the top: three-stage rocket using liquid hydrogen, liquid oxygen storage temperature were minus minus 253 ℃ and 186 ℃, although the level of the fuel tank was very high insulation design, the air around the rocket, or quickly is condensed into water vapor, in order to prevent freezing, to keep blown with nitrogen until the last few seconds before launch.

"1 minute to prepare!" To support the rocket pendulum quickly laid out, with the rocket on the launch tower system equipment connected to the moment of loss, "Long March III C" blasted off from the stage has entered the countdown. "... ... 5,4,3,2,1," Launch Control issued a master manipulator Hao Jun Password "Ignition", and press the red "fire" button. 18:59:57, orange flames spewing out from the bottom of the rocket.

Quite true, "Chang'e II" again to achieve a "zero window" launch. 3 years ago, "Chang'e One" to achieve a "zero window" launches satellite fuel savings of 120 kg, making the time of the satellite in orbit longer than 4 months, and ultimately hit the month.

■ Secret

Moon had two set "Wedding"

"Chang'e II" National Day this year, just launch the satellite, the satellite experts point out that this coincidence is "the motherland 61 years old birthday gift the universe's natural gifts."

After a comprehensive calculation, the experts from the timing of the launch in 2010 selected the two "best", one in April, one in October, two opportunities to the launch window was 3 days. Combination of rockets, satellites, the progress, the experts determined the final time the launching of 10 March, the October 1, 2, 3, a total of three windows of time, October 1 for the first launch window.

"Chang'e II" for the lunar exploration phase to fully test and validate the technology. One of them is to verify that the earth-moon transfer orbit launch technology. The technology to be considered in the relationship between the day to also meet the star when the satellite is separated from the rocket point of flying to the moon, solar panels expand direct sunlight when the satellite as soon as the mission to the Moon and other requirements.

Rocket mostly "fear" the wind rain thunder

Xichang Satellite Launch Center, said station technical staff, rocket launchers on the climate and the environment is not high, but there are three conditions can not be fired.

The first is a lightning storm weather. Unfortunately, if the rocket was struck by lightning, it will directly damage the rocket, severe cases may lead to both satellite and the rocket destroyed. The second situation is strong rains. If the rocket bodies for a long time in the rain soaked the state, can also cause damage to the internal or line of electronic equipment short-circuit. The third situation is the wind. Rockets fly tower, the wind will occur elegant rocket bodies, which deviate from the trajectory.

Rockets will not happen, "bird strike" incident? Rocket technology experts the answer is no, because the launch of high Wengao Liang flame and the deafening roar, the birds would shy fei tao. In the Xichang launch center, a launch site surrounded by trees and luxuriant, and not near the bird Device.

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