Ariana Grande tried to lock down the best space song of 2019 with “NASA,” but that was before the planet Mars released a mixtape with some pretty innovative sounds.
On Tuesday, NASA—the agency, not the song—posted several sonifications of data captured on Mars by InSight, a robotic lander that touched down on the red planet in May 2018.
InSight is the first mission ever to record “marsquakes,” the Martian equivalent of earthquakes, which it detects with an instrument called Seismic Experiment for Interior Structure (SEIS), made by the French space agency.
SEIS has now heard about 100 weird tremors rippling through the interior of Mars, 21 of which have been identified as likely marsquakes. For instance, here’s an audio representation of a magnitude 3.7 marsquake detected on May 22, 2019, which was SEIS’ 173th “sol” (the word for a Martian day) of operation.
NASA dialed the seismic frequencies recorded by SEIS up to a range that can be heard by the human ear, but you may still need headphones to get the full experience. The quake sounds a bit like the kind of ambient bass-heavy hum you might expect to play during a tense scene in a movie thriller.
NASA’s second recording—a magnitude 3.3 marsquake that took place on July 25, 2019—has a slightly different profile, especially towards the end, as the pitch drops and the vibrations get more intense.
These quakes are probably caused by rocks breaking or shifting in the interior of Mars, which sends seismic waves rippling through the planet to the surface.
On Earth, seismic waves travel much more rapidly through the ground because geological processes, such as plate tectonics and the water cycle, plug gaps in Earth’s crust, according to NASA. In contrast, the dry interior of Mars is probably filled with hollow nooks and crannies that interrupt the flow of seismic waves through the planet, and cause the vibrations to persist for longer periods relative to Earth.
SEIS is so sensitive that it picks up other vibrations in its environment, such as wind gusts or the movement of InSight’s robotic arm. Recordings of these tremors are a few tweaks away from sounding like Darth Vader’s robot breath.
NASA also released sounds produced by the SEIS instrument itself, which mission scientists think are caused by the equipment cooling down at the end of a long workday (or, in Martian parlance, work-sol).
The above sample was recorded after sundown on July 16, 2019, and adds a chill percussive counterpoint to the bassy quakes and windy echoes.
All in all, it seems as if Mars is putting out some of the most original music in the industry. Rock on, red planet.