Xihe is the "mother of the sun" in ancient mythology in my country. She has ten sun sons, and only one out to "work" every day: Xihe drove the dragon cart, set out from Tanggu , passed 16 stations, and arrived at Menggu, day after day, forming the morning and evening of the earth, year after year, and the world has since become warm.
, a beautiful mythological image, was used to name my country's "first solar exploration science and technology experimental satellite" - " Xihe ". Nearly a year after the successful launch on October 14 last year, the "Xihe" has been serving us with strict activity trajectory. As of August 30 this year, the artificial satellite has accumulated 50Tbit of original observation data and generated 300Tbit of scientific data.
On August 30, 2022, at the first results press conference of the "Xihe", Wu Yanhua, deputy director of the National Space Administration, concluded that "Xihe" set "five international firsts".
html On September 19, at the Tencent Youth Science Conference site, Zhao Jian, chief designer and deputy commander-in-chief of the National High-resolution Earth Observation System and director of the National Space Administration's Earth Observation and Data Center, told the young audience about the "Xihe" sun exploration project, and used three "keywords" to decrypt these five "first times". Zhao Jian said that it is a great thing that the "Xihe" has created five international "firsts", because it marks that our country has officially entered the era of space "Daily Discovery". The "break" and "establishment" of Xihe's
Sun is known as the "devil planet". Due to the violent nuclear fusion movement that has been underway within, it creates more energy per second than the total amount of energy created by human society.
While the sun brings temperature and energy to the earth, it also "produces" threats at all times. In 1859, the largest "sun superstorm" in history visited the earth unexpectedly, causing losses to mankind was about US$2 trillion; in March 1989, the Canadian province of Quebec was cut off by 12 hours due to the solar storm , which affected more than 6 million people.
Even in today's highly developed technology, in order to avoid damage from the sun, the best method is to predict that the abnormality was detected by satellite , which "guarded" the sun, giving humans 20 hours to prepare for the response. Since the 1960s, aerospace technology has developed rapidly. More than 70 solar observation satellites have been launched around the world, focusing on the observation and research of sunspots , flare and coronal mass ejection.
"Xihe" represents my country's observation of the sun. It was approved by the National Space Administration in June 2019. On October 14, 2021, the CZ-2D Y53 carrier rocket was successfully launched into orbit by the CZ-2D Y53 launch vehicle at the Taiyuan Satellite Launch Center . It operates in a solar synchronous orbit with an average altitude of 517 kilometers, and the main scientific load is a solar Hα imaging spectrometer.
Zhao Jian decrypted the "Xihe number", and the first keyword is "Shuangshuang". "Double Super" refers to ultra-high pointing accuracy and ultra-high stability. These two indicators determine the accuracy and scientificity of the data obtained by the satellite during operation. Zhao Jian revealed that the direction accuracy of the "Xihe" reached three-tenths of a degree, and the posture stability reached 6.3 degrees per 100,000 per second. These two indicators have been increased by 1 to 2 orders of magnitude compared to the same inertia satellite, reaching the international advanced level.
"In layman's terms, it is the photographer of 'Xihe'. Not only does it point accurately, but it also takes steady shots." Zhao Jian explained in his speech that "accuracy" is measured by "pointing accuracy of three ten thousand degrees". "The Earth's equator is 40,000 kilometers long, and it passes three ten thousand degrees above the equator, and the length is about 33 meters." When talking about "stability", Zhao Jian first compared our usual photos, "because the hand shaking or the stand is unstable, the photo will be vague." "Xihe" uses unique skills similar to "magnetic levitation" to achieve ultra-high stability. It can be kept motionless and blindly blinking during the detection process.
The second keyword is "solar speed tester". The satellites are flying in space, and they also need to locate navigation services to accurately obtain their own position and speed.In the early days, scientists used inertial navigation to guide satellites, but it was prone to drift and had large accumulation errors; later it was improved to navigation satellites, but the power range of satellite navigation was limited to "near the earth", and there was nothing we could do when we arrived in space; and the atomic frequency solar speed test navigator installed on the "Xihe" is the first time in the world. Zhao Jian revealed that her positioning "accuracy can reach 2 meters per second."
The third keyword is "spectral imager". "Xihe" has achieved the first international orbital spectrum scanning imaging of the solar Hα band. The Hα band spectral line in the solar spectrum is the strongest chromosphere spectral line when the sun bursts, which can directly reflect the characteristics of the source region of the burst. Previously, no other countries in the world were able to use Hα band scanning to image until the "Xihe" appeared.
It is understood that the "Xihe" loaded with an Hα imaging spectrometer can better observe the sun in two ways: white light continuous spectrum imaging and spectral scanning imaging. In white light continuous spectrum imaging mode, you can get a full-day surface image, as simple as people press the shutter to take a picture. In the spectral scanning imaging mode, the Hα imaging spectrometer equipped with "Xihe" scans the sun's full-day surface and obtains more than 4,600 spectra in 46 seconds. Each spectrum can be restored to a lunar image, just as he made a metaphor at the meeting, "it seems to be doing CT for the sun."
Through the analysis of Hα spectral data, information about the low atmosphere of the sun can be obtained from the photosphere to the chromosphere, thereby deducing the changes in physical quantities such as atmospheric temperature and velocity during the sun's burst, and studying the dynamic process and physical mechanism of the sun's burst. The fruits of the
Xihe satellite mark the official entry of my country's "independent Japanese exploration" era.
From "Running the Moon" and "Exploring the Fire" to "Exploring the Sun"
"Independent Sun" means that we have gained autonomy in spatial data. Before
, the source of weather forecast data in my country's space mainly relies on foreign countries, which can easily cause data delays and is difficult to guarantee. After the "Xihe" came to heaven, we independently controlled these data and were no longer restricted. In addition, in recent years, the field of international solar exploration has developed rapidly, and my country has ranked second in the world in the number of papers published in this field. However, in previous scientific research results, the cited data are all from abroad. The emergence of "Xihe" will completely reverse this situation.
my country has opened the sharing of "Xihe" data to the world. Zhao Jian revealed in his speech that it can be "queried and downloaded through Nanjing University's Sun Science Data Center". According to international online reports, the scientific data of "Xihe" has been widely used by scholars in solar physics research in the United States, France, Germany and other countries.
"Xihe" "surveillances" the sun in space to ensure the safety of our production and life on the earth as much as possible, and the earth we live in is also being "closely" watched by seven high-score satellites.
As the chief engineer of the "high score" special engineering, Zhao Jian raised the first question to young people in his live speech at the Science Conference: What is "high score"? "It is to observe the eyes of the earth at all times." Just as the higher the resolution of a mobile phone, the clearer the photo taken, the "High Score" 7 satellite has achieved "sub-meter level" shooting photos of the earth in space. It not only has high resolution, but also achieves high timeliness, high spectral resolution, and high positioning accuracy, with time reaching the second level, the spectrum has hundreds of spectral segments, and the positioning accuracy is also meter-level.
In February this year, at the opening ceremony of the Beijing Winter Olympics, the aerial view of the competition venue imaged using "Gaofen 2" satellite was shown, and "visited" the Winter Olympics stadium from a space perspective, reflecting the spirit of the Science and Technology Olympics.
Gaofen 2's "big brother" - "Gaofen 1" satellite was launched into orbit on April 26, 2013. It has provided high-precision and wide-range spatial observation services to my country's land and resources department, agriculture department, meteorological department, and environmental protection department. For example, the Ministry of Public Security used Gaofen 1's data to discover many poppy cultivation areas in Heilongjiang, Inner Mongolia, Hebei and other places. In July 2013, after the earthquake occurred in Minxian County, Gansu, Gaofen 1 obtained the data and provided scientific guidance for the assessment of secondary disaster detection work in the disaster area.
The high-resolution earth observation system "designed" by my country includes seven satellites and corresponding observation platforms, covering a variety of types from full-color, multi-spectral to hyperspectral, from optical to radar , from solar synchronous orbit to geosynchronous orbit, and has built a ground observation system with high spatial resolution, high temporal resolution and high spectral resolution capabilities.
"Whether it is observing the earth or detecting the sun, these are just some areas of space science," Zhao Jian said, so what is space science? "It is mainly the science of using spacecraft to study the natural phenomena and laws of physical, astronomical, chemistry and life that occur in sun-earth space, interplanetary space and the entire universe."
From this perspective, my country's space science that uses spacecraft to "study" the moon and Mars has also reached a leading level. The observation of the moon is marked by the implementation of the "Chang'e Project" in 2004. The latest result is a lunar soil study collected by " Chang'e 5 ". This lunar probe, , landed on the moon in December 2020, and then sampled the lunar surface material near the landing site and successfully brought 1,371 grams of lunar soil samples back to Earth.
Recently, the research team of Institute of Geochemistry, Chinese Academy of Sciences found that there is a large amount of solar wind water in the lunar soil brought back by Chang'e 5. This result was published in the international academic journal Nature Communications. Previously, remote sensing detection has found that water is common on the lunar surface. Due to the lack of direct sample analysis evidence, the causes and distribution of the lunar surface water have always been controversial. This study of of the Chinese Academy of Sciences provides an important reference for studying the distribution of water in the mid-latitude area of the lunar table.
spacecraft exploring Mars has also made breakthrough progress in recent years. In July 2020, the " Tianwen-1 Mars rover " was successfully launched in Wenchang, Hainan. This is my country's first exploration mission for Mars. " Tianwen-1 " lasted for 7 months, flew 750 million kilometers, and landed on Mars in May 2021. Although
is the first step in exploring Mars, the steps taken are of great significance. "Tianwen-1" became the second country after the United States to officially land on Mars and continue to send clear pictures back, which can be said to have broken the United States' technological monopoly position on "landing on Mars".
Looking up at the starry sky, you also need to grab
from the doll "The sunset on Mars is not red, but light blue. There is also a moon on Mars, but it is a little small. It cannot cover the sun and cannot form the total eclipse of the earth. There is a unique Phobos transit on Mars, and it is also spectacular in a few dozen seconds." The moon and Mars rover deputy general design Jia Yang , describes the sunset and celestial phenomena of Mars to children. "The significance of exploring Mars is to add a perspective to mankind. From this perspective, we look at Mars, the earth, the solar system, the entire universe, and also examine human beings themselves."
"Why should we detect and study ' dark matter '"? Director of the National Observatory of the Chinese Academy of Sciences, Chang Jin, answered this question on the spot: China must truly become a world power and contribute to the common dream of mankind, and must not be absent in the field of cutting-edge science. He told the children that so far, the "Wukong" scientific satellite has patrolized the sky 13 times, and has detected the number of high-energy particles as high as 13.5 billion times, and its more than 70,000 sensors are still in a near-perfect state. How did it do it? "It's very simple and not easy, that is to do every little thing down-to-earth."
Director of the Shanghai Observatory of the Chinese Academy of Sciences Shen Zhiqiang, Director of the Key Laboratory of Particle Astrophysics of the Chinese Academy of Sciences and Researcher of the Institute of High Energy Physics of Zhang Shuangnan also popularized the audience with black holes, Intelligent Eye Satellite and other cosmic matter and cutting-edge detection methods. From basic knowledge to the latest progress, it can be said that a country's top "cosmic group" is doing science to young people. Behind the luxurious lineup like
is the importance of popularizing the aerospace science of youth.
, compared with the United States, Russia (including the Soviet era), Japan, Europe and other countries, although my country's deep space exploration field started late, it started at a high starting point. For example, as early as the 1960s, the United States and the Soviet Union had already implemented human lunar landing plans. It was not until 2004 that my country's "Chang'e Project" began to be implemented, but the success rate reached 100%. "Tianwen-1" also became the second satellite to land on Mars in the world. The first satellite to land on Mars was the United States' "Pathfinder" in 1997...
is in the face of a series of phased achievements, my country has also made relatively clear plans for deep space exploration: the asteroid exploration plan before 2030 is called the "living fossil" of the origin of the solar system, and once successful scientific research is of great value; from 2025 to 2030, scientists have also planned Jupiter system exploration and planetary crossing plans. According to this timetable, my country will reach Jupiter by 2036; after 2030, more refined and far-reaching robot deep space exploration is expected to be launched, and it will reach Uranus by around 2048.
These seemingly distant stars and seas are symbols of a country's future comprehensive national strength and also represent the common destiny of mankind. It requires continuous investment of a large amount of manpower, material resources and financial resources, and Today's youth group is the "reserve army" of this cause. In the matter of "looking up at the starry sky", a seed of curiosity was planted for teenagers, and perhaps they could grow into a towering tree in the future. On November 16, 2020, the national leaders pointed out at a scientist symposium, "Curiosity is human nature. The guidance and cultivation of scientific interests should start from children, so that they can understand scientific knowledge more, master scientific methods, and form a large group of young people with the potential of scientists."
To make popular science for young people more interesting and high-quality, it is also necessary for all sectors of society to form a joint force, create a good atmosphere of advocating science, and improve the system and mechanism of science education. By 2022, Tencent Science Conference has reached its fourth session, and has attracted more than 40 million young people to listen to scientists' sharing through the lineup of top scientists, customized interesting content, platforms and creative capabilities.
Science Club is more like a connector. On one hand, it is the public and teenagers, and on the other hand, it is the integration of scientist resources and high-quality content, so that more teenagers have the awareness of scientific exploration and plant a seed of science. As Li Hang, vice chairman of Tencent Youth Development Committee, said at the opening of the briefing: "The history of human science is the history of scientific development, and it is also the history of the inheritance of scientific predecessors and future generations. In fact, looking around the world, many scientists have been inspired by senior scientists in their youth. We hope that today's encounter with scientists can plant a seed for you and bloom gorgeous flowers in your life in the future."
