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The instrument package SEIS (Seismic Experiment for Internal Structure) with the two co-located seismometers VBB and SP is installed on the surface of Mars as part of NASA's InSight mission. When compared to terrestrial installations, SEIS is deployed in a very harsh wind and temperature environment that leads to inevitable degradation of the quality of the recorded data. The daily atmospheric temperature variations of approx. 80K are attenuated by different insulation layers to approx. 15K peak-to-peak at the sensor level. Typical wind speeds vary between 0 and 5 m/s leading to a diurnal variation in the broad-band rms noise level by two orders of magnitude. One ubiquitous artifact in the raw broad-band data is an abundance of one-sided, transient pulses often accompanied by high-frequency spikes. We show that these pulses, which we term "glitches", can be modeled as the response of the instrument to a step in acceleration, while the spikes can be modeled as the response to a simultaneous step in displacement. We attribute the glitches primarily to intermittent stress relaxation events internal to SEIS caused by the large diurnal temperature variations to which the instrument is exposed during a Martian sol. Only a small fraction of glitches correspond to a motion of the SEIS package as a whole caused by minuscule tilts of the instrument. Whilst such kind of data disturbances are typically discarded when occurring in terrestrial data, this is no option for the data returned from the Red Planet. We therefore do not only demonstrate their effects on the seismic data and analyze their origins, but also propose algorithms that are able to detect and remove many of these (mostly) non-seismic signals. We further published our codes (both Python and MATLAB) so that interested researchers can make their own choices on how to treat the data and to which extent.

The instrument package SEIS (Seismic Experiment for Internal Structure) with the three very broadband and three short‐period seismic sensors is installed on the surface on Mars as part of NASA's InSight Discovery mission. When compared to terrestrial installations, SEIS is deployed in a very harsh wind and temperature environment that leads to inevitable degradation of the quality of the recorded data. One ubiquitous artifact in the raw data is an abundance of transient one‐sided pulses often accompanied by high‐frequency spikes. These pulses, which we term “glitches”, can be modeled as the response of the instrument to a step in acceleration, while the spikes can be modeled as the response to a simultaneous step in displacement. We attribute the glitches primarily to SEIS‐internal stress relaxations caused by the large temperature variations to which the instrument is exposed during a Martian day. Only a small fraction of glitches correspond to a motion of the SEIS package as a whole caused by minuscule tilts of either the instrument or the ground. In this study, we focus on the analysis of the glitch+spike phenomenon and present how these signals can be automatically detected and removed from SEIS's raw data. As glitches affect many standard seismological analysis methods such as receiver functions, spectral decomposition and source inversions, we anticipate that studies of the Martian seismicity as well as studies of Mars' internal structure should benefit from deglitched seismic data., Plain Language Summary: The instrument package SEIS (Seismic Experiment for Internal Structure) with two fully equipped seismometers is installed on the surface of Mars as part of NASA's InSight Discovery mission. When compared to terrestrial installations, SEIS is more exposed to wind and daily temperature changes that leads to inevitable degradation of the quality of the recorded data. One consequence is the occurrence of a specific type of transient noise that we term “glitch”. Glitches show up in the recorded data as one‐sided pulses and have strong implications for the typical seismic data analysis. Glitches can be understood as step‐like changes in the acceleration sensed by the seismometers. We attribute them primarily to SEIS‐internal stress relaxations caused by the large temperature variations to which the instrument is exposed during a Martian day. Only a small fraction of glitches correspond to a motion of the whole SEIS instrument. In this study, we focus on the detection and removal of glitches and anticipate that studies of the Martian seismicity as well as studies of Mars's internal structure should benefit from deglitched seismic data., Key Points: Glitches due to steps in acceleration significantly complicate seismic records on Mars. Glitches are mostly due to relaxations of thermal stresses and instrument tilt. We provide a toolbox to automatically detect and remove glitches., Centre National d'Etudes Spatiales (CNES), InSight PSP Program, Agence Nationale de la Recherche http://dx.doi.org/10.13039/501100001665, ANR‐19‐CE31‐0008‐08