The mark of "aliens" between the ridges: the amazing discovery of Hailin crater

Author: Duan Yuechu and Huang Xianghong

In the north of Hailin City, Heilongjiang Province, the mountains are towering like the majestic backbone of the earth. Among the peaks and ridges, there is a treasure that shocked the world - the Hailin meteorite crater. This area has long been shrouded in the tranquility of nature and rarely visited by people. It is like a mysterious corner forgotten by the world, quietly sealing its shocking secrets.

Until recent years, a group of Chinese scientists with a passion for exploration and fearless courage set foot on this mountain forest. Like persistent treasure hunters, they have embarked on a journey of exploration that rewrites the scientific cognition map with their keen ability to capture subtle clues in nature. The team members bring together elites from many fields such as geology, astronomy, and geophysics. For example, Professor Li, a senior geologist, has been with the mountains for half his life and has an extraordinary insight into the changes in rock formations; Dr. Zhang, who focuses on near-Earth object research in the field of astronomy, is good at analyzing the trajectory and composition of meteorites; and there is also the young and innovative geophysicist Researcher Wang, who has cutting-edge detection technology and can accurately "see through" underground structures.

The initial opportunity came from the vague local geographical legends and Professor Li's unexpected discovery during a field survey - the rock texture in a certain ridge area was arranged in a peculiar concentric circle shape, and the mineral content of the surrounding soil fluctuated abnormally. This subtle but special anomaly made them realize that this land might be full of hidden treasures.

Then came the rigorous and arduous research process. First, the topography and geology were surveyed. With their rich field experience, the team members hiked through the mountains and forests, carefully drawing topographic maps, not missing any suspicious signs, and marking potential points. With the help of portable geological testing equipment, basic parameters such as soil density and rock hardness were measured. Soon, the local area showed data that was completely different from the surrounding area, which further ignited their passion for exploration.

Then, high-precision detection technology came on the scene. Researchers brought in high-precision geological radar and geophysical electromagnetic detectors to conduct a comprehensive and detailed "scan" of the underground rock formations. Radar images revealed the existence of a huge, low-resistance anomaly area with an elliptical bowl-shaped structure underground, which is suspected to be the remains of a large impact crater; at the same time, electromagnetic detection data showed that the magnetic susceptibility of rocks in the area was abnormal, and all signs indicated that it had been subjected to strong external impact, most likely caused by a meteorite impact, and the mineral magnetic structure had been changed. After locking the target, it was the sampling and laboratory analysis stage. Researchers carefully collected hundreds of soil and rock samples at different depths, brought them back to the laboratory, and used advanced instruments such as electron microscopes and mass spectrometers to deeply explore the mineral composition of the samples. Sure enough, they found a variety of impact metamorphic minerals such as coesite and stony quartz. The formation of such minerals requires an ultra-high pressure environment (hundreds of thousands of atmospheres), and the high-speed impact of asteroids can create such extreme conditions, which undoubtedly became the "iron evidence" for determining the meteorite crater.

After years of unremitting efforts and repeated verifications, the Hailin crater has transformed from an initial vague guess into a conclusive scientific fact. The relevant scientific research results were published in the internationally renowned journal "Matter and Radiation under Extreme Conditions", like a bright new star rising in the night sky of the scientific community, instantly attracting the attention of the global academic community.

The Hailin crater is not just a spectacular geographical wonder, its scientific research value is a rich mine that needs to be explored. From the perspective of Earth's history, it is a "frozen image" of an asteroid impact on Earth hundreds of thousands of years ago. By studying the impact angle of the crater wall rock layers, the distribution of sputtering and the direction of mineral deformation, scientists can accurately calculate the speed, angle and energy release value of the asteroid at the moment of impact, vividly depicting the shocking scene of the Earth suffering from an "attack from outer space" at that time, further clarifying the profound impact mechanism of such disasters on ancient ecology and ancient climate, and filling the gaps in the details of major events in geological history; it is also a "living archive" that records the movement and deformation process of surface material on the Earth, from the evolution of mountain folds and faults at the edge of the crater to the accumulation of sediments in the crater, clearly showing the interaction of internal and external forces such as crustal uplift, erosion, and deposition, helping scientists understand how magmatic activity and plate movement inside the Earth sculpt the surface and uncover the laws of environmental change in different geological periods; moreover, the closed environment in the crater is like "ecological amber", which preserves ancient animal and plant fossils, pollen and special sediments intact. Researchers can use this to reconstruct regional vegetation coverage and animal community succession before and after the impact, interpret temperature and precipitation change curves, provide precious regional evidence for global paleoclimate research, and calibrate the accuracy of climate models.

Switching to the dimension of cosmic exploration, meteorite craters are also of great significance. As the "elders" of the solar system, asteroids retain information about the early solar system materials in their own composition and structure. Analyzing the chemical elements and isotope ratios of the meteorite fragments in the Hailin crater can infer the material distribution pattern and condensation process in the early formation of the solar system, track the growth and migration trajectory of planetary embryos, and improve the theoretical framework of the origin and evolution of the universe; the number of known meteorite craters on Earth is limited, and the appearance of the Hailin crater has greatly expanded the sample library. Based on its scale and age data combined with global meteorite crater statistics, scientists can more accurately estimate the frequency and scale of extraterrestrial impacts, lay a solid foundation for the formulation of planetary defense plans (covering monitoring and early warning systems, interception strategies), and protect the safety of the Earth's home; meteorites and impact metamorphic rocks in the crater are engraved with traces of "processing" in the universe. Studying the crystal structure of special minerals and the abundance of trace elements can unlock the codes of physical and chemical processes such as cosmic ray irradiation and micrometeoroid impacts, deepen the understanding of the diversity of cosmic matter and the complexity of evolution, and help the frontier exploration of astrophysics.

In terms of scientific theory innovation, the Hailin crater is located on a mountain ridge, and its special terrain challenges the traditional impact crater model. In-depth research on the energy propagation and scattering mechanism in the mountainous terrain during the crater formation process, as well as the special forms of rock fragmentation and ejection, will help to correct and improve theoretical formulas and parameters, and enhance the ability to predict and interpret craters in different terrains; the high pressure (up to millions of atmospheres) and high temperature (thousands of degrees Celsius) at the moment of asteroid impact give rise to exotic material states and chemical reactions. Based on the samples from the crater, scientists can open up new frontiers for high-pressure physical and chemical research, explore new compound synthesis pathways, and give rise to basic theoretical innovations.

After the results were announced, the academic community responded enthusiastically. Professor Peterson, an internationally renowned geologist, praised it as a "treasure of earth science", praising its unique topography and preservation state, setting a model for studying the geological effects of continental impacts, and reshaping the research pattern of the internal tectonic evolution of the plate; Academician Zhao, an authority on domestic astronomy, also pointed out that it is a "window" to gain insight into the early evolution of the solar system, making an outstanding contribution to expanding the depth and breadth of my country's astronomical research, and consolidating the theoretical foundation of deep space exploration and planetary defense strategy.

As the scientific community is excited, the local cultural tourism industry is also keen to seize opportunities. The government plans to build a science theme park based on the meteorite crater, with supporting facilities such as science trails, astronomical observatories, and interactive experience halls, aiming to popularize scientific knowledge, stimulate the public's enthusiasm for exploration, and turn the Hailin meteorite crater into a "cradle" for improving the scientific literacy of the whole people, maximizing the social benefits of scientific research results.

Today, the Hailin crater has bid farewell to obscurity and transformed itself from an ordinary geographical depression into a popular science frontier with a scientific mission. It is foreseeable that with the continued in-depth research, this "legendary crater" between the ridges will surely bloom more brilliant scientific research flowers and bear fruitful results, leading mankind to steadily advance on the long road of exploring the universe and interpreting the earth, and continuously expanding the in-depth understanding of the wonderful symbiotic relationship between the universe and the earth.