Zero distance
Looking back on "Fengyun" for half a century
——Enlightenment from "Catch-up from Zero" to "Partially Leading"
Meteorological forecasters half a century ago can hardly imagine that in today's China, an image of any regional cloud over the vast land can be "looked at as you want"——
In space 800 kilometers and 36,000 kilometers from the earth, 7 Fengyun satellites overlook the global wind and clouds; from the north to the Arctic Circle and south to the Antarctic continent, there are massive satellite data receiving, processing and distributing; every 5 minutes, there is one Zhang Xin’s cloud map of China’s region was sent back, and it took less than 10 minutes from the satellite lens to the forecaster’s phone screen...
"Meteorological satellites should be supplied as long-term as tap water!" This description from Sun Jiadong, the winner of the "Republic Medal" and the chief designer of the Fengyun-2 Meteorological Satellite Project, has transformed dreams into reality.
At the media briefing on the 50th anniversary of the Fengyun Meteorological Satellite Business recently held by the China Meteorological Administration, Yang Jun, director of the National Satellite Meteorological Center and chief designer of the Fengyun Meteorological Satellite Project, said that in the 50-year development of China Fengyun Satellite, generations of scientists have relied on Constantly exploring and overcoming difficulties, Fengyun Satellite, which "starts from scratch", has achieved a leap from "following" to "partially leading" by means of "small steps".
According to him, China’s second-generation geostationary meteorological satellite Fengyun-4A launched in 2016 can achieve observation coverage of China’s region once every 5 minutes. The maximum resolution has been increased from 1.25 kilometers to 500 meters, and this is the first time in the world. Atmospheric hyperspectral vertical detection in geostationary orbit, the comprehensive detection level is internationally leading; the Fengyun-3D satellite launched in 2017 is equipped with the world’s first imaging instrument that can obtain the world’s 250-meter resolution infrared split window data. The gap acquires infrared images of the world with a resolution of 250 meters.
"This kind of'unique in the world' capability provides Chinese observation programs for the global ecological environment, disaster monitoring and climate assessment. The Fengyun satellite is very complete in the system. It can be said that we have the detection capabilities owned by other countries. All of us, Some of them don't." Yang Jun said.
Successive failures at the start, "Wind and Cloud" shrouded in haze
In China 50 years ago, the industrial foundation was weak, the equipment was rudimentary, and the technology was backward. Not to mention building their own weather satellites and using their own weather satellites. Many scientific research and technical personnel did not even know what weather satellites are and what they do.
"How difficult is it to start from scratch?" Yang Jun said: During the 50-year development of Fengyun Satellite, we have encountered every possible problem in spaceflight.
But failure is the mother of success.
According to him, the Fengyun-1 polar orbiting meteorological satellite was successfully launched. When the researchers got the first picture, Zou Jingmeng, then director of the China Meteorological Administration, was presiding over an international conference. At the meeting, he gave the first picture to the experts at home and abroad. After a "show", there was thunderous applause in the audience-the fact that China has become a country with weather satellites shocked the world.
However, due to attitude control problems, the first Fengyun satellite only worked for 39 days before disappearing into the vast space.
The road to development afterwards has not been smooth sailing.
According to Dong Yaohai, chief designer of the Fengyun 4 satellite system, recalled: In 1990, the Fengyun 1 B satellite was launched. After more than 10 days, the satellite became abnormal, and it was declared invalid after only 158 days of operation.
In 1994, an accident occurred during the pre-launch test of Fengyun-2 01.
In 1997, the FY-2A satellite was successfully launched, but it failed after a few months of operation, and finally it was not commercialized.
Successive failures at the start have cast a haze over the "Fengyun" satellite business.
Dong Yaohai said that the first problem that needs to be solved after the satellite is successfully put into operation in the sky is reliability and service life.
After three generations of hard work and key research, the technical problems affecting the long-life operation of the satellite have been solved.
It wasn't until the turn of the century that the haze of "Wind and Cloud" finally dissipated.
In 1999 and 2002, my country successfully launched the Fengyun-1 C and D service stars. The service life of the satellites in orbit reached 6 years, 5 months and 10 years respectively, which greatly exceeded the design life.
From 2004 to 2008, the Fengyun-2 C, D, and E operational satellites were successfully launched, and the operating life in orbit reached 8 to 10 years.
Apart from learning and cooperation, there is no other way out
"There is no other way out except study and cooperation." This is a sentence from Sun Jiadong, and many "Fengyun" people think it is appropriate to describe the period of low and prosperous period.
What makes people feel emotional is that when Fengyun-1's A and B service life failed to reach the target and were greatly questioned, the two bombs and one star champion Ren Xinmin, who was "enchanted", led the scientific and technical personnel. Analyze the reasons, and personally report to the relevant state departments, requesting support for "our meteorological satellite team" to go; in order to overcome the problems of the first two Fengyun 2 satellites, he was the chief engineer of the Fengyun 2 satellite ground application system. Xu Jianmin, deputy chiefs Li Xizhe, Zhang Qingshan and all team members, day and night, boarded the Qinghai-Tibet Plateau to carry out the "savior" experiment, solving the "positioning" problem in tens of thousands of handwritten calculations, not only bringing the satellite back to life, but also It also makes "every point on the image becomes very accurate"... Generations of scientific and technological workers have paid the hard work and sweat, and even the cost of their lives, to lay the foundation for the rapid catching up of meteorological satellites.
Today, Fengyun-4 satellites are providing satellite data and products to more than 2,700 domestic users in 115 countries and regions around the world.
Yang Jun said that according to internationally accepted standards, Fengyun Satellite has a very high benefit in reducing disaster losses and serving economic and social development, and its input and output can reach 1:40.
He said that my country is a country with very serious natural disasters. Natural disasters such as floods and mudslides caused by heavy rainfall, sandstorms caused by drought and strong winds, and forest fires ignited by lightning occur frequently every year. More than 70% of natural disasters are caused by weather. Caused by.
"Meteorological issues have been thoroughly studied, and most disasters except earthquakes can be understood. This is why all countries are vigorously developing meteorological satellites." Yang Jun said.
Tang Shihao, deputy chief designer of the Fengyun Meteorological Satellite Project, gave a set of data: Since the Fengyun 2 satellite was put into operation to the end of August 2020, 566 typhoons generated in the Western Pacific and 165 typhoons landed in my country, "monitoring has not missed the net!" "
Tang Shihao said that after the Fengyun-4 satellite is put into operation, the time for monitoring and identifying disasters such as typhoons and rainstorms in my country has been shortened from 15 minutes to 5 minutes, the rainstorm warning accuracy rate has increased to 89%, and the average 24-hour typhoon path forecast error has been reduced from 95 kilometers. As small as 71 kilometers, it is better than the United States, Japan and other countries.
Why "Fengyun" can catch up in a short time
The technological capability of China Fengyun Satellite is advancing so fast that many well-known international experts are amazed and curious: the United States launched its first meteorological satellite in 1960, Europe launched its first meteorological satellite in 1974, and China until The first meteorological satellite was launched in 1988. What is the internal development logic of Fengyun satellites that can catch up in a relatively short period of time?
Yang Jun said that Fengyun Satellite was a large-scale system project undertaken when our country was relatively backward in technology and insufficient in national strength.
Half a century ago, Comrade Zhou Enlai put forward with a foresighted approach to "make our own weather satellite" and personally approved the task of developing a weather satellite in 1970.
On September 7, 1988, my country successfully launched the Fengyun-1A polar-orbiting meteorological satellite and obtained clear remote sensing images. Since then, it has bid farewell to the history of relying solely on foreign meteorological satellite data.
Recalling the scene at the time, Zeng Qingcun, the winner of the National Highest Award for Science and Technology and an academician of the Chinese Academy of Sciences, sighed with emotion: "I was in tears at the time. Nearly 20 years have passed since we decided to release our own weather satellite, and finally there is a will!"
As the person who experienced the research and development of the Fengyun-3A satellite, Yang Zhongdong, the deputy chief designer of Fengyun Meteorological Satellite Project, recalled: The Fengyun-3A satellite launched in 2008 was the first satellite of the second-generation polar orbit.
In order to concentrate on research and development, the scientific research team pulled the technical backbone in a remote guest house in the suburbs, and worked for 4 hours in the morning, 4 hours in the afternoon, and 4 hours in the evening.
"This satellite uses a new generation of technology, and a lot of work is done for the first time. We discussed very intensely. A colleague’s dream talked about the content of the discussion-when dreaming, what was going on in our satellite project The matter!" Yang Zhongdong said.
When talking about the next development of Fengyun satellites, Yang Jun revealed that in the near future, Fengyun-4B and Fengyun-3E will also be launched into space.
Among them, after the launch of the Fengyun-3 E satellite, it will be the first international operational satellite to operate in the morning and evening orbit.
The satellite is very eye-catching internationally.
Yang Jun mentioned a detail. When my country announced this plan a few years ago, applause immediately broke out at the World Meteorological Organization meeting, believing that China's move will enhance the global numerical weather forecast capability and improve the forecasting level.
"This satellite is not only to help China itself, but the whole world will benefit." Yang Jun said.
The Fengyun-4B star is even more worth looking forward to. It is the first operational star of the Fengyun-4. Its launch will mark the formal entry of the Fengyun-4 into business and will enable my country's stationary meteorological satellites and meteorological services to upgrade and accelerate in all aspects.
Yang Jun said that because the weather system is constantly changing, the pouring rain may be fleeting. In the past, meteorological satellites could only observe once every half an hour, and it is possible to miss these trends.
The Fengyun-4B star has high-precision minute-level imaging capability in a stationary orbit. It can make changes in the weather system appear in front of people in high-definition all-weather for the first time through spectacular, clear and smooth animations.
"I believe that in the near future, whether it is satellites or applications, my country should reach the international leading level." Tang Shihao said.
"Before I retire, I think it should be visible." He added.
Lu Jian, China Youth Daily, China Youth Daily reporter Qiu Chenhui Source: China Youth Daily
Version 12 on November 03, 2020