日团队首次测定小行星“龙宫”原材料物质形成时间

Group 1 - The research team led by Hokkaido University has successfully determined the formation time of the materials constituting the asteroid "Ryugu," which is approximately 4.5673 billion years ago, shortly after the birth of the solar system [1][2] - The study indicates that the original solid materials of celestial bodies provide crucial insights into their origins, with previous analyses showing that the minerals from "Ryugu" were formed around 4.562 billion years ago from low-temperature aqueous solutions [1] - The research utilized scanning electron microscopy to analyze "Ryugu" samples, revealing the presence of calcium-aluminum inclusions formed in high-temperature regions exceeding 1000 degrees Celsius in the early solar system [2] Group 2 - The study found that the sizes of calcium-aluminum inclusions in "Ryugu" rock samples are generally below 0.1 millimeters, while those in other carbonaceous chondrites are relatively larger, suggesting a connection to the transport processes of early solar system solid materials [2] - This discovery provides valuable data for understanding the origins of the solar system and planet formation, potentially advancing related research [2]