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  The probes have been launched one after another, and our country has entered the era of "exploring the sun"

  Since ancient times, the sun has caused too many human thinking. We are full of curiosity about this dazzling star: Why does it glow?

Does it exist forever?

What is the structure?

What impact will it have on the planet?

In order to answer these questions, scientists have not only developed corresponding theoretical foundations, but also built or launched various detectors to try to unravel the mystery of the sun.

  On October 14, my country’s first solar exploration science and technology experimental satellite "Xihe" was successfully launched, achieving a zero breakthrough in my country's solar exploration, marking my country's space exploration officially entered the "sun exploration" era.

  What are the unsolved mysteries of the sun, a star closely related to the survival of mankind?

How will scientists explore the sun in the future?

  Qilu Evening News Qilu One Point

  Reporter Yu Meijun

  "Xihe" successfully launched

  my country enters the era of Japanese exploration

  "The sun has an indispensable role in the evolution of the earth and the development of human civilization. At the same time, the impact of the sun on the earth is also ubiquitous. It is mainly reflected in the large number of charged high-energy particles produced by the sun erupting, causing serious damage to the electromagnetic environment of the earth, especially sunspots, Flares and coronal mass ejections have the most significant impact on the electromagnetic environment of the earth." According to Zhao Jian, director of the National Space Administration’s Earth Observation and Data Center and chief designer of a major special project for high-resolution Earth observation, the solar activity cycle is about 11 years, 2021 The year 2022 is the beginning of the 25th solar cycle since human record, and the world has entered a new peak period for solar research.

  "Detecting and studying solar activities and proposing countermeasures can reduce or circumvent the adverse effects on the earth. As a large aerospace country, it is very necessary for my country to carry out solar exploration activities in a timely manner and cannot be absent." Zhao Jian said.

  The full name of the "Xihe" satellite launched this time is the solar Hα spectrum detection and dual super platform science and technology test satellite, and the main scientific payload is the solar space telescope.

  The "Xihe" star weighs 508 kilograms and has a design life of 3 years. It will operate in a sun-synchronous orbit with an altitude of 517 kilometers and an inclination of 98 degrees.

The "Xihe" satellite has realized the world's first space exploration of solar Hα-band spectral imaging, which will fill the gap in high-quality observational data in the source area of ​​the solar burst.

  In addition, the "Xihe" satellite uses a new type of satellite platform technology with ultra-high pointing accuracy and ultra-high stability for on-orbit tests.

Compared with traditional satellite platforms, the pointing accuracy and attitude stability of the "Xihe" satellite platform have been improved by two orders of magnitude.

After the successful in-orbit test of the "Xihe" high-performance technology satellite platform, it is the world's first engineering application of maglev technology on a spacecraft, which will greatly enhance the level of my country's space observation technology.

  "Kwafu" launches next year

  my country will explore the sun in three dimensions in the future

  Since the 1960s, the world has launched more than 70 solar observation satellites, mainly in the United States, Russia, Japan and other countries, focusing on the observation and research of sunspots, flares and coronal mass ejections.

  In October 2006, the United States launched the world’s first pair of twin solar observation satellites, the Sun-Earth Relation Observation Platform, to perform three-dimensional imaging of sunspots when sunspots broke out; in January 2009, Russia launched the "Coronas" solar exploration satellite. Detect the influence of the internal structure of the sun and solar activities on the Earth’s climate, atmosphere and biosphere; in 2018, the US "Parker" solar probe was launched into space to detect the structure of the sun at close range.

  my country has currently formulated two solar exploration plans. The "Xihe" has realized the ice-breaking journey of my country's solar exploration, and the "Kwafu" plan is to develop and launch advanced space-based solar observatory satellites, revealing the solar magnetic field, solar flares and coronal mass ejection. The formation and interrelationship of (one magnetism and two storms) are planned to be launched next year.

  In addition, my country is demonstrating the follow-up solar exploration development plan. Scientists hope to implement the “three steps” of multi-view detection in the ecliptic plane, large-inclination solar polar region detection, and solar approach observation to further understand the structure of the sun and determine the sun. Active three-dimensional structure.

  It is envisaged that my country will use two launch missions (one arrow three stars, one arrow two stars) around 2035 to construct an all-round three-dimensional circle around the ecliptic plane (the orbital plane of the earth orbiting the sun) and the solar polar region. The detection system realizes the three-dimensional detection of the sun's global and solar-terrestrial space.

  Three of the sun

  unsolved puzzle

  There are still many unsolved mysteries about the sun, the most important of which are three scientific questions.

  The first question: Why is there periodicity in solar activity?

The driving force of the solar activity phenomenon comes from the magnetic field on the sun, and its strong magnetic field structure is characterized by sunspots, which are also relatively low temperature regions on the solar photosphere.

Sunspots have an 11-year cycle, and their long-term changes are closely related to the Earth’s climate. For example, during the Little Ice Age (about 1300-1850) in climatology, solar activity was significantly weaker than the average level of subsequent years.

  In 1908, the American astronomer Haier discovered that sunspots are a strong magnetic field on the sun, confirming the existence of magnetic fields in cosmic bodies for the first time and also revealing that solar activity originates from the solar magnetic field.

However, how is the solar magnetic field produced?

Why does its dominant solar activity have periodic changes?

These problems are called the mystery of the origin of the solar cycle.

  Second question: Why is the corona so hot?

Like the earth, the sun can also be divided into many levels from the inside to the outside, including the solar nucleus (temperature approximately 15 million ℃), radiation area (approximately 7 million ℃), convection area (approximately 2 million ℃), and photosphere (thousands). ℃), chromosphere (thousands to tens of thousands of ℃), corona (million ℃).

It can be seen that the temperature structure of the sun is obviously different from that of the earth, the outermost corona of the sun’s atmosphere presents an abnormally high temperature state, which violates the second law of thermodynamics. How to explain the heating mechanism of the corona is an important part of astrophysics. Scientific problems.

  The third question: How to observe and forecast the solar-geophysical propagation process and interplanetary effects of solar activity in real time?

In March 1989, a violent coronal mass ejection triggered a very strong geomagnetic explosion, causing a large-scale power outage in Quebec, Canada.

The main goal of solar exploration is to better understand the solar-terrestrial system and predict changes in the space environment and their social impacts.

Therefore, a complete physical image depicting the spread and influence of solar activity in the solar-terrestrial space is the most cutting-edge scientific issue of contemporary solar-terrestrial physics.

  In the three major scientific issues, the magnetic field plays a vital role.

However, due to the limitations of current observation capabilities and technical means, humans have not yet fully understood the solar magnetic field.

This leads to another basic problem in astrophysics: the process of magnetic convection of fibrillated radiation in the stellar atmosphere.

  Solar probe

  Future focus of competition

  After the successful implementation of the landmark PSP (Parker Solar Probe) and Solar Orbiter (Solar Orbiter) in the United States and Europe, the detection hotspots in related international fields have focused on the last gap in solar detection-the detection of the solar polar region.

  Regardless of space-based or ground-based observations, when we are in the ecliptic, due to the projection effect and the edge dimming effect, it is very difficult for us to observe the solar polar region.

This difficulty is equivalent to the fact that two people of similar size cannot see the top of each other's heads.

Humans have not yet achieved frontal imaging observations of the solar polar region. Although Solar Orbiter deviates from the ecliptic plane, its deviation angle is only more than 20 degrees. Even if the mission's final plan is increased to 34 degrees, the height difference between the two is not enough to see. Clear the top of the other's head.

  Studies have shown that the magnetic field and flow field of the solar polar region play a vital role in the evolution of the solar cycle.

Improving the observational data in this area, so as to complete the last observation puzzle of the "generator model" about the origin of the solar activity week, is expected to bring about a major breakthrough in the study of this scientific problem.

  Because of these major scientific opportunities, the next hot spot for international space exploration must be solar polar orbit exploration.

  At present, space science development plans in Europe and the United States have all put forward the idea of ​​solar polar orbit detection.

As early as 10 years ago, my country put forward the project proposal for the development of solar polar orbit exploration in the "Moon and Deep Space Exploration" plan.

At present, my country's pre-research in this area is in a position equal to or even slightly ahead of the international level. Considering that the PSP and Solar Orbiter have just been implemented in the United States and Europe, China has an excellent opportunity to take the lead in implementation. Once the project is successful, it will surely enable my country's space solar exploration has achieved rapid overtaking.

At the same time, seize the opportunity in the research of major scientific issues such as the origin of solar cycles and the origin of high-speed solar wind.

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