“洞察”号火星表面地震探测中的发现

Discoveries of the InSight seismic investigation on Mars'surface

“洞察”号任务是火星探测历史上一次巨大的飞跃.本文从介绍“洞察”号的科学目标和火星表面地震观测实验出发,展示“洞察”号地震数据中的发现.受益于“维京”2号的火星探测经验,“洞察”号首次成功监测到了火星震信号,并由此得到了火星壳结构的衰减特征.火星的地震数据中检测到了由气压引起的地表形变和HP3打孔信号,并用于约束登陆点附近表面土层的物理性质和地下结构的反演.此外,使用在2.4 Hz处出现的结构响应能够辨别自然响应和登陆器自振等机械振动.火星的地震数据中也检测出了Glitch和Donk等噪声信号,我们总结了其特征和形成原因.“洞察”号对火星壳的探测比较成功,但是由于缺乏大震级的火星震和陨石撞击事件的记录,对火星深部的了解依然比较有限.

The InSight mission is a great milestone in the history of Mars'seismic exploration after the Viking 2 lander.We first review the scientific goals of the InSight mission and its seismic observation experiment on Mars'surface.We then present the discoveries in the InSight seismic data.Both the pressure-induced ground deformation and the HP3 self-hammering signals were detected by the InSight seismic instrument.These data are further used to constrain the physical properties of the surface regolith and the inversion of the underground structure at the In-Sight landing site.Besides,the structural resonance around 2.4 Hz allows us to distinguish the natural response from the mechanical vibration such as the lander mode.Non-seismic noise like the glitches and donks were also found in Mars'seismic data,and their characteristics and possible origins will be summarized.The InSight mission has successfully explored the structure of Mars'crust,while the exploration of Mars'deep interior is still limited because there lacks large-magnitude Marsquakes and meteorite impact events.