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News of the "sound of the wind" on Mars is all over the internet today. If you read the fine print, it's really better described as rapid cadence barometric pressure measurements then sped up by a substantial amount (I think it's of order 10x to 100x) or seismometer data reflecting the interaction of the wind with InSight inducing ground vibrations (sped up as well).

What is InSight's actual maximum sample rate for barometric pressure and seismic accelerometers, and what do their "frequency response" plots look like?

NASA's SoundCloud page InSight Lander Sounds of Mars has both kinds of recordings, but doesn't list many technical data about the digitization or speed-up factors.

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The page at the NASA Planetary Data System Planetary Atmosphere Node on the Temperature and Wind for InSight (TWINS) instrument and Pressure Sensor (PS) has a description of the instrument and data production. The native sampling on the spacecraft of the pressure sensor is 20 Hz (20 times a second) but this is normally downsampled to 2 Hz for downlink. There is support during anomalous "events" detected by the pressure or seismic sensors to download data at higher sampling rates of 10 Hz, 5 Hz or 4Hz.

The SEIS instrument is briefly described in this software interface specification. Section 2.6 describes the instrument which is made up of 2 parts: the Very Broad Band (VBB) 3-axis seismometer and a MEMS (microelectromechanical systems) Short-Period (SP) 3-axis seismometer. Section 2.6.2 states:

During science operations, VBB is continuously sampled at 20 Hz and SP is continuously sampled at 100 Hz.

The full instrument paper SEIS: Insight’s Seismic Experiment for Internal Structure of Mars by Longonne et al. 2019 (open access) shows the frequency response plots in their Figure 5.Root mean squared self-noise of the three main outputs of the SEIS instrument

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  • $\begingroup$ thorough and well-sourced answer, thank you! $\endgroup$ – uhoh Jan 15 at 1:12

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