Why Mars is the first choice for deep space exploration

Human exploration of Mars began in the 1960s. The Soviet Union launched the first Mars probe in 1960. After more than 60 years of development, from early flybys and orbiting explorations to today's landing and patrol explorations, Mars has become the most explored and studied terrestrial planet by humans.

Mars is also the focus of current solar system exploration and planetary science. Mars exploration is of great significance for studying the early history of the solar system and exploring the origin of life. It is also of great value for understanding and protecting the Earth and expanding living space, and it helps to achieve sustainable development of human society.

Mars surface

Mars has many secrets

Mars is Earth's neighbor and may have life or be suitable for life to thrive, making it the most important exploration target in the solar system.

Mars is an average of 2.28 million kilometers from the sun, about 1.5 times the distance between the sun and the earth. Its volume is 1/4 of the earth, its weight is 1/10, and its surface gravity is 40% of the earth. Mars in the night sky is a dark red planet with greatly varying brightness, like a bonfire on the horizon.

Mars is located in the habitable zone of the solar system, and its environment is very similar to that of the Earth. The average surface temperature is -55°C, which can reach 28°C during the day and -132°C at night. Mars rotates once in 24.66 hours, which is more than half an hour different from one day on Earth. Its revolution period is 687 days, which is equivalent to 1.9 years on Earth. Mars has four seasons, and each season lasts about 6 months. Mars also has an atmosphere, but it is very thin, and carbon dioxide accounts for 95%.

Most importantly, there is liquid water on Mars. Although the surface of Mars is now completely dry, there are traces of water erosion in many areas, and the criss-crossing riverbeds show that Mars once had large and small lakes and oceans. In 2002, the United States announced the discovery of a large amount of ice from images and data of the South Pole of Mars. In 2018, scientists discovered 20 kilometers of liquid water under the South Pole ice cap of Mars.

The process of human exploration of Mars is similar to that of the Moon. With the advancement of technology, the exploration is gradually deepening in the steps of orbiting exploration, landing exploration, patrol exploration, sample return and manned landing. At present, humans have achieved orbiting exploration, landing exploration and patrol exploration. my country's "Tianwen-1" completed three exploration steps in one mission, which is a remarkable achievement.

Tianwen-1 lander

At present, Mars exploration has reached the stage of sampling and returning. my country's Tianwen-3 probe is scheduled to be launched in 2028 to collect samples on Mars. The US Perseverance Mars rover has already started its sampling mission, but these precious samples will not be sent back to Earth until 2033.

Mars exploration has great scientific significance

The origin and evolution of the solar system, the search for extraterrestrial life and habitable environments, and the origin and evolution of planets are the three major scientific themes of contemporary solar system exploration, and Mars contains valuable clues.

In order to explore the origin of the solar system, humans are constantly looking for early materials and information about the formation of the solar system, all of which may be preserved on Mars. Sampling and analysis at different locations on Mars are of great value to the study of the formation process, chemical composition, and internal differentiation of Mars.

The origin and evolution of Mars provide us with samples of planets other than Earth. Many signs indicate that Mars had an environment suitable for life a long time ago, but after billions of years of evolution, it became the barren land it is today. In addition, Mars' magnetic field is very weak and cannot block the invasion of high-energy particles from the solar wind on the surface of the planet. There is also an ozone hole in the atmosphere above Mars.

These phenomena and problems are of great reference value for our research on the evolution of the magnetic field, its effects on planets, and the impact of the ozone hole on the Earth. They are also of great significance for us to correctly understand the changing trends of the Earth's environment and protect it.

The most important direction of Mars exploration is to find traces of life. According to current research results, the basic conditions for the birth of life are liquid water, energy and the basic elements that constitute life. We have discovered water resources on Mars in the form of polar ice and groundwater, and methane in the atmosphere. Mars has long been located in the habitable zone of the solar system, and its temperature and atmosphere provide suitable conditions for the cultivation of life. It is the closest place in the universe where we can find extraterrestrial life.

If evidence of life is found, it will have an important impact on how humans understand life in the universe. Countless stars and planets are scattered throughout the universe. Is life universal? If the environment is suitable and the basic conditions are met, life will arise. The universe will be more lively than we imagined, and this secret may soon be revealed on Mars.

Can drive technological development

Mars exploration is a systematic project that crosses multiple disciplines and has highly integrated technologies. Breakthroughs in key technologies will drive innovative development in basic fields such as space astronomy, space physics, and space materials science. Exploration results will promote progress in disciplines such as planetary science, cosmology, and Martian life science. The progress of these disciplines will in turn drive the cross-disciplinary, infiltration, and common development of more basic disciplines.

Mars exploration is also the most cutting-edge scientific and technological innovation activity in the world today. Compared with the moon landing, Mars is farther away from the earth, the environment is more unfamiliar, and the implementation difficulty and technical challenges have increased sharply. It has become the strategic commanding heights of international space technology and the primary goal of planetary exploration.

So far, humans have conducted 47 Mars exploration missions, with a success rate of about 53%. With the continuous improvement of aerospace technology capabilities, the success rate has increased to about 80% since 2000. Even so, only a few countries in the world, such as the United States, the Soviet Union, the European Union, India, and the United Arab Emirates, have achieved Mars exploration, and only the United States and China have been able to land on Mars. It can be said that Mars exploration is a touchstone for a country's aerospace capabilities.

Before the launch of Tianwen-1, my country had no actual flight experience on Mars, no first-hand environmental data, and had not launched a Mars relay satellite in advance, but achieved the three major goals of orbiting, landing, and patrolling Mars in one mission. The Tianwen-1 system is very complex, with a high starting point and a big technological leap.

The successful implementation of this mission is the result of concentrating scientific research forces from all aspects of the country, pooling wisdom to tackle key problems, and making breakthroughs in innovation. It is also the result of the gradual development and maturity of my country's technologies in large-thrust rockets, deep space tracking and control, orbit design, high-precision flight control, deep space autonomous navigation, and landing on extraterrestrial bodies. It means that my country has become one of the world's leaders in deep space exploration.

The first choice for space immigration

Today, we are in a new era with unprecedentedly advanced technology, abundant material resources, rapidly growing population, and highly civilized society. At the same time, we are also facing new major crises, such as abnormal climate, environmental pollution, population explosion, energy crisis, etc. There are two ways to solve these problems. One is to strengthen governance, protect the environment, limit population, and achieve sustainable development under limited resource conditions; the other is to break out of the earth, open up new horizons, and expand the overall living space of mankind.

The ultimate goal of human exploration of space is to take the second path and open up living space. With the continuous deepening of Mars exploration and research, it will be the first choice for human space migration.

The US Mars Helicopter on the surface of Mars

The current environment on Mars is still very harsh and cannot meet the basic needs of human survival. The atmosphere is too thin, the oxygen content is low, and the temperature difference between day and night is large. But Mars has more advantages. It is one of the planets closest to humans and has all the resources needed to support life.

Scientists have proposed that by further enhancing the greenhouse effect on Mars, raising the surface temperature, forming surface water flows, cultivating photosynthetic fungi and mosses, and gradually launching a tree planting program, the composition of the Martian atmosphere can be changed. After one to two centuries of unremitting efforts and changes in the world, Mars can be transformed into a paradise and a second home for mankind.

The realization of all this depends on human beings' detailed exploration of Mars. We need to investigate the mineral rocks of Mars, analyze the distribution of Martian resources and environmental characteristics, and lay the foundation for large-scale landing on Mars and resource utilization in the future. Today we have taken the first step towards this beautiful future. Just as more than 100 years ago, people could hardly imagine that they could sit in a spacious plane and cross the ocean to another continent, perhaps 100 years later, any person on Earth can take a flight to Mars. (Author: Yang Shirui)