詹姆斯·韦布空间望远镜对72个年轻类日恒星及其原行星盘的观测揭示了行星形成过程中气体逃逸的演化规律1。研究团队利用中红外仪器观测这些原行星盘，在66个盘中检测到分子氢和电离氖的扩展辐射，其中46个系统出现圆锥形分子氢风，40个系统发现快速移动的氖喷流1。
这项研究表明，驱动气体逃逸的主导机制随系统发展阶段而改变——早期强劲的磁驱动喷流和风逐步过渡到后期由恒星辐射驱动的光蒸发风1。这一机制转变对气体巨行星的形成施加了严格的时间限制1。在太阳系早期数百万年内，气体质量约为尘埃质量的100倍1。
研究人员指出，"行星形成因此成为与时间的竞赛"1，这意味着气体巨行星必须在气体大规模流失之前快速积累其大气层。该研究已发表于《天文学杂志》2026年第172卷第3期1。
The James Webb Space Telescope has provided new insights into how planets form by observing the mechanisms that strip gas from young planetary systems. A study of 72 sun-like stars and their protoplanetary disks revealed that the processes driving gas escape change dramatically as systems mature.1 Researchers detected extended emission from molecular hydrogen and ionized neon across 66 of the observed disks, while 46 systems showed conical molecular hydrogen winds and 40 exhibited rapid-moving neon jets.1
The findings highlight a critical timeline constraint for planet formation. Early in a system's development, powerful magnetic-driven jets and winds dominate gas removal, but over time this transitions to photoevaporation winds driven by stellar radiation.1 This shifting mechanism creates a limited window for gas giant planets to accumulate their atmospheres. According to the research team, "What is exciting about this study is that we can now see, across a large sample of young systems, how the mechanisms that remove gas from planet-forming disks change with time."1 In the solar system's early stages, gas mass was approximately 100 times greater than dust mass within the first few million years.1 As one researcher noted, "Planet formation is therefore a race against time."1 The findings were published in The Astronomical Journal in 2026, volume 172, issue 3, page 161.1
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