"In the contemporary exploration of the solar system, lunar exploration is the starting point, Mars exploration is the hot spot, asteroid exploration is the highlight, and interplanetary crossing exploration is the difficulty." Ouyang Ziyuan, an academician of the CAS Member and the first chief scientist of the China Lunar Exploration Project, recently imagined the possibility of deep space exploration in the future. On September 8th, at the keynote speech on "The Future of China Europe: Advancing towards the Sea of Stars in the Solar System", Ouyang Ziyuan introduced the struggle of China's aerospace industry. He said that since 1958, China has been tracking and researching the progress and achievements of foreign lunar exploration, proposing its own lunar exploration plan based on its national conditions. By 1978, China had completed research on Apollo lunar rocks. From the first Lagrangian L2 point lunar orbit by the Chang'e-2 lunar satellite to the first automatic sampling and return of extraterrestrial celestial bodies by the Chang'e-5 lunar probe, China has made significant scientific and technological breakthroughs. China's lunar exploration project is steadily advancing. Where will we fly next? Ouyang Ziyuan proposed that in contemporary solar system exploration, lunar exploration is the starting point, Mars exploration is a hot spot, asteroid exploration is the highlight, and interplanetary exploration is the difficulty. At present, we have taken the first step. The previous implementation of circumlunar satellite exploration, lunar soft landing exploration and lunar rover survey, lunar soft landing exploration and sampling return has accumulated experience and technology for China's manned lunar landing and lunar base construction. Ouyang Ziyuan introduced that by 2030, after basically completing unmanned lunar exploration missions, China will build a lunar scientific research platform, select opportunities to carry out manned lunar exploration, and build manned lunar bases to develop and utilize lunar resources. In the future, may we still fly out of the solar system? Ouyang Ziyuan said: It's difficult. He explained this viewpoint with a cross-sectional view of the solar system: the radius of the solar system is between 100000 to 200000 astronomical units, which is 15 to 30 trillion kilometers, and the length is approximately 3 light years. Assuming that human aircraft fly at a third cosmic speed (16.7km/s), it will take at least 30000 years to fly beyond the boundaries of the solar system. The Voyager 1 and Voyager 2 spacecraft, launched in 1977, are currently approximately 28 billion kilometers away from Earth, and these two spacecraft have been flying for 46 years during this journey. Looking at the entire solar system, the distance they have flown is less than one thousandth of the diameter of the solar system. We still have a long way to go for deep space exploration. (New News Agency)