马斯克的星链卫星为何突然大批坠落？最新研究：太阳活跃度增强使其寿命缩短

Core Insights - NASA's research indicates a clear correlation between satellite falls and solar activity, with increased solar activity shortening the operational lifespan of Starlink satellites in orbit [2] - SpaceX has launched over 8,000 Starlink satellites since 2019, with 7,578 currently operational as of May 30, 2025 [2] - The lifespan of each Starlink satellite is typically less than five years, leading to a significant number of satellites re-entering the atmosphere and burning up [4] Group 1 - In 2020, two Starlink satellites fell, while the number surged to 78 in 2021, and remained high in subsequent years, with 316 satellites burning up in 2024 [4] - The current solar activity cycle is stronger than the previous one, with sunspot activity following an approximately 11-year cycle of intensity [4] - Increased solar activity leads to magnetic storms that heat the upper atmosphere, causing it to expand and create greater drag on satellites, resulting in their eventual fall [4] Group 2 - Interestingly, 72% of the satellites fell during weak magnetic storms rather than strong ones, suggesting a cumulative effect of resistance during the rising phase of the solar activity cycle [5]