"Giant sunspots suddenly appear on the sun's surface", could it paralyze the phone network? Is the danger really approaching the earth?

Not long ago, a piece of news about a "huge sunspot on the surface of the sun" became a hot topic, and it was mentioned that this sunspot might release a high-energy explosion. For a time, various shocking statements such as "may paralyze the earth's power grid" and "may release a high-energy explosion" flooded the Internet, causing heated discussions.

What is this “giant sunspot”?

It is understood that this was taken by NASA's "Perseverance" Mars rover while exploring the Jezero Crater on Mars from August 17 to August 20. Because Mars is currently running on the back of the sun, "Perseverance" saw the sunspot more than a week earlier than people on Earth.

Sunspot images taken by Perseverance

Sunspots are small black spots that appear on the solar photosphere. It is generally believed that sunspots have a strong magnetic field that is 10,000 times stronger than the Earth's magnetic field. They are not "black", but the strong magnetic field inhibits the transfer of energy from the sun's interior to the outside, resulting in lower temperatures in local areas, which look like dark spots. In years when sunspots are active, "magnetic storms" will occur, causing serious interference to the Earth's magnetic field and radio communications. Therefore, it is inevitable that some people will speculate that this "giant sunspot" may release a "high-energy explosion."

In fact, there is no day without sunspots on the surface of the sun. We can see them on Earth with the help of entry-level telescopes and Baader films. So how does Perseverance see sunspots on Mars?

On Mars, as long as there is no sandstorm, it is not difficult to see sunspots. This phenomenon can even be seen on every planet in the solar system. Of course, telescopes are required on the four outer gas planets. As early as August 20, the JPL laboratory of NASA, responsible for the operation of the Perseverance Mars rover, announced that it had photographed sunspots on Mars and released photos.

The picture shows the sunspots photographed by JPL laboratory on Mars

Why do we say that this big sunspot will face the Earth in a week?

The reason for “see you in a week” is that Mars and the Earth have different orbits and revolution periods.

At present, the Earth and Mars are located on either side of the Sun, with an angle of about 130 degrees in between. In this way, the Earth and Mars are like standing on both sides of the Sun and "watching" it at the same time. If the Earth sees the front of the Sun, then Mars sees the side and rear.

Coupled with the rotation of the sun, the sunspots previously photographed by the Mars rover have actually slowly moved to the side facing the Earth, which is the active area numbered 13415 in the picture. Considering that it takes about 27 and a half days for the sun to rotate once, this video was calculated from the time the rover sunspot photos were released. The statement that the Earth saw it after a week is basically reliable. However, to say that it is a "shocking appearance" is too exaggerated, and the area of ​​this sunspot is far from huge in the world of sunspots!

The active area numbered 13415 in the picture is the sunspot that has been slowly turned to face the Earth as photographed by the Mars rover. / Nanjing University Xihe Team

"Release high-energy explosion, global power outage"?

It's really exaggerated!

Sunspots rarely act alone, but usually appear in groups. When active, they will affect the Earth's magnetic field. When a large group of sunspots appears on the sun, magnetic storms will occur, causing the compass to shake violently and fail to indicate the direction correctly; homing pigeons that are usually very good at identifying directions will get lost.

As for causing major power outages, they have indeed happened in history. For example, the major power outage in Quebec, Canada in 1989 was caused by the energy released by the sun's coronal mass ejection reaching the Earth, causing drastic changes in the Earth's own magnetic field and triggering a geomagnetic storm.

However, there is no need to panic too much. According to the judgment of the space weather forecaster of the National Space Weather Monitoring and Early Warning Center, the possibility of this sunspot undergoing strong explosive activity is not high.

However, judging from the several sunspot activity areas currently visible on the solar surface, it is almost impossible for an extremely high-energy explosion to occur, and naturally it is impossible to produce a super-large geomagnetic storm that can paralyze the power grid.

In fact, natural "amplifiers" such as sunspots, flares, and prominences can give humans the opportunity to study the solar magnetic field in more detail. With the advancement of science and technology, scientists are also strengthening the monitoring and research of solar activity through various means and methods to keep abreast of the changing trends of solar activity. At the same time, it is also necessary to strengthen the monitoring of the Earth's magnetic field and ionosphere in order to promptly discover possible problems and formulate effective response strategies.

Solar flare.

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There are still some unsolved mysteries about the sun

Although the Sun is so important to humans, today, with the advancement of science, we already have a very good understanding of the Sun's mass, age, size, and total irradiance. We also know how it evolved into its current "appearance" and its future fate, but humans' understanding of its internal mechanics and chemical composition is still limited.

01 Why is solar activity periodic?

The driving force of solar activity comes from the magnetic field on the sun. The strong magnetic field structure is represented by sunspots, which are also relatively low-temperature areas 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. Not only that, the activity of sunspots also has a great impact on the earth's magnetic field and wireless communications. The "Carrington" solar flare event in 1859 caused severe geomagnetic disturbances and severely damaged the high-tech system of human society at that time - the global telegraph network, which made humans realize for the first time the impact of solar activity on the earth's space environment.

In 1908, American astronomer Hale discovered that sunspots are strong magnetic fields on the sun, which confirmed for the first time the existence of magnetic fields in celestial bodies and revealed that solar activity originates from the solar magnetic field. However, how is the solar magnetic field generated? Why does solar activity dominated by the solar magnetic field change periodically? These questions are called the mystery of the origin of the solar activity cycle. This is an essential problem of the highly nonlinear and complex system of the sun. The scientific community still cannot give a clear explanation. It has been listed as one of the 125 most cutting-edge scientific problems facing contemporary human society by Science magazine.

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02 Why is the temperature of the corona higher than that of the sun’s surface?

The outermost layer of the sun's atmosphere (corona) is located above the sun's surface, farther from the heat source, but its temperature is 1,000 times that of the sun's surface. The temperature structure of the sun is obviously different from that of the earth, where the temperature decreases as you go outward. The outermost layer of the sun's atmosphere, the corona, is abnormally high in temperature, which violates the second law of thermodynamics. Why does this happen? This is a "mysterious veil" shrouding the sun.

How to explain the heating mechanism of the solar corona is a major scientific problem in astrophysics, and is called one of the "eight unsolved astronomical mysteries" in astrophysics by Science magazine.

03 How to conduct real-time observation and prediction of the solar-terrestrial physical propagation process and interplanetary effects of solar activity?

This is a crucial application requirement to ensure the smooth progress of high-tech equipment and deep space exploration in nearby space. In March 1989, a violent coronal mass ejection triggered an extremely strong geomagnetic storm, resulting in a large-scale power outage in Quebec, Canada. During this magnetic storm, the entire power grid in Quebec was completely paralyzed within 90 seconds, causing direct economic losses of approximately US$500 million. The major solar activity event in October 2003 caused global shortwave communication interruption, over-the-horizon radar, civil aviation communication interruption, Swedish power grid interruption for 1 hour, GPS navigation failure, and data loss of multiple scientific satellites. The National Aeronautics and Space Administration (NASA)'s "Report on the Development of Solar Physics and Space Physics" also clearly pointed out that the main goal of solar exploration is to better understand the solar-terrestrial system, predict changes in the space environment and their social impact. Therefore, depicting a complete physical picture of the propagation and impact of solar activity in the solar-terrestrial space is the most cutting-edge scientific issue in contemporary solar-terrestrial physics, and it is also an urgent need for various major scientific and technological powers.

In the above three major scientific issues, magnetic field plays a vital role. In fact, the understanding of the properties of the magnetic field of the sun and stars is also an important scientific issue. Whether for the development of science and technology or national security, solar exploration is so important that it has become the focus of competition in the fields of astronomy and space physics in various countries.

my country's first solar exploration scientific and technological experimental satellite "Xihe" (satellite schematic diagram). Image source: National Space Administration

Thanks to the substantial improvement in national strength, China has the economic strength to invest in the exploration of major scientific issues; and relying on the improvement in hard power brought about by the national lunar exploration, deep space exploration, and manned space flight, my country has also acquired the technical strength to carry out major solar exploration missions. Time waits for no one, and we look forward to China's solar observation research reaching the top of the world as soon as possible.

Comprehensive sources: Xinhuanet, Science and Technology Daily, China Meteorological News Agency, etc.