From the stars and the light of Mars' two smaller moons, Phobos and Deimos, you can only make out the size of a rising delta.
Tonight the wind is so slow that it can't even push a grain of sand. Everything is calm and peaceful
Then, out of nowhere, comes a foreign, mechanical whistling noise, and a misshapen head pops out of the darkness, its five eyes glowing alarmingly.
For one thing, the Mars Environmental Dynamics Analyzer (MEDA) continues to take weather data throughout the night.
The Supercam microphone also routinely records three minutes of sound at very high frequencies at night, which tells us a lot about small-scale atmospheric turbulence
The Mars Oxygen In-Situ Resource Utilization Experiment (MOXIE) also schedules oxygen generation, typically running at night.
The scanning habitable environment with Raman and Luminescence for Organics and Chemicals (SHERLOC) instruments also operates at night
This is because operating at night provides the least instrument noise and thus the most sensitive detection
It provides a measure of the amount of dust in the nighttime atmosphere, using visible light
Which can be compared to similar measurements made by observing the Sun during the day.
So at least perseverance can take comfort in not being the only one working the dreaded night shift.