Explosive mass ejections triggered by magnetic activities are common on our Sun and other stars in the Universe. However, there is a lack of evidence for such explosive phenomena in magnetized or partially magnetized planets with atmospheres. Here we present direct evidence for explosive mass ejections from the Martian ionosphere, resulting from magnetic reconnections between strong crustal field regions with open magnetic fields. A plasma density cavity with signatures of magnetic reconnection that is directly evident for an eruptive mass ejection caught in the act indicates that a considerable amount of ionospheric mass has been rapidly ejected into space. Although Martian mass loss associated with magnetic reconnection has been reported previously, our results demonstrate that explosive mass ejections can occur even on partially magnetized planets without global magnetic fields. In this scenario, we suggest that strong localized magnetic fields extending above the exobase are needed.

由磁活动引发的爆炸性物质抛射在太阳和宇宙中的其他恒星上很常见。然而，缺乏证据表明在有大气层的磁化或部分磁化行星中存在这种爆炸现象。在这里，我们提供了火星电离层爆炸性物质抛射的直接证据，这是由于强地壳场区域与开放磁场之间的磁重新连接造成的。具有磁重联特征的等离子体密度空腔对于在该行为中捕获的喷发质量喷射是直接明显的，表明相当数量的电离层质量已被快速喷射到太空中。尽管之前已经报道过与磁重联相关的火星质量损失，但我们的结果表明，即使在没有全球磁场的部分磁化行星上，爆炸性物质抛射也可能发生。在这种情况下，我们建议需要在外碱基上方延伸的强局部磁场。