The first to be rigged with microphones, the agency’s latest Mars rover picked up the subtle sounds of its own inner workings during interplanetary flight.


A microphone aboard NASA’s Mars 2020 Perseverance rover has
recorded the sounds of the spacecraft as it hurtles through interplanetary
space. While another mic aboard
the rover is intended specifically to listen for the laser zaps of the SuperCam instrument, this one is devoted to capturing
some or all of the entry, descent, and landing
(EDL) sequence
– from the firing
of the mortar that releases the parachute to the Mars landing engines kicking
in to the rover wheels crunching down onto the surface.

Data for the 60-second audio file was collected on Oct. 19
during an in-flight checkout of the camera and microphone system that will pick
up some of the landing drama at Mars’ Jezero
Crater
early next year.

You can listen to the sound file here:

The subdued
whirring you hear is from the rover’s heat rejection fluid pump. Located at the
rear-starboard side of the Perseverance, the pump is part of the rover’s
thermal system, which will help maintain operational temperatures for vehicle components
on even the coldest of winter nights. It does its job by circulating fluid
through a heat exchanger mounted adjacent to the always-toasty Multi-Mission
Radioisotope Thermoelectric Generator
and then into a network
of tubes spread throughout the rover’s chassis.

“With
apologies to the person who came up with the slogan for ‘Alien,’ I guess you
could say that in space no one may be able to hear you scream, but they can
hear your heat rejection fluid pump,” said Dave Gruel, lead engineer for
Mars 2020’s EDL Camera and Microphone subsystem. “The microphone we
included to hear what it’s like to land on Mars was actually able to pick up
Perseverance’s thermal system operating in the vacuum of space through mechanical
vibration.”




In this annotated illustration, the location of the Perseverance rover’s entry, descent, and landing microphone is shown. Image credit: NASA/JPL-Caltech

› Larger view

Good Vibrations

As any fan of cinematic sci-fi knows, the vacuum of space is a less-than-optimal environment for
auditory transmissions. But that doesn’t mean sound can’t find another way. Sound
waves can travel through solid objects. When these mechanical vibrations are registered
by an electrical component, they sometimes are turned into an electrical
signal. (Anyone listening to music through in-ear headphones may have encountered this phenomenon as a rustling or thumping
noise when the headphone cord brushes up against a surface.)

The sound
file was processed by DPA Microphones of Alleroed, Denmark, which manufactured the EDL microphone
hardware flying on Mars 2020.

“As
great as it is to pick up a little audio on spacecraft operations in-flight, the
sound file has a more important meaning,” Gruel added. “It means that
our system is working and ready to try to record some of the sound and fury of
a Mars landing.”


An electrical cable can be seen snaking its way along insulation material in this in-flight image of the interior of the Mars 2020 spacecraft

An electrical cable can be seen snaking its way along insulation material in this in-flight image of the interior of the Mars 2020 spacecraft on its way to the Red Planet. The picture was assembled using three images taken by the Perseverance rover’s rear left Hazcam during a systems check on Oct. 19, 2020. Image credit: NASA/JPL-Caltech

› Larger view

The EDL microphone
was not tailor-made for this mission – or space exploration – and the team does
not know quite what to expect from their sound files of landing day.

“Getting
sound from landing is a nice-to-have, not a need-to-have,” said Gruel. “If
it doesn’t happen, it will not impede the rover’s mission of discovery at
Jezero Crater one bit. If even a portion of the landing sequence is captured on
audio, that would be awesome.”

Humanity’s
most sophisticated rover is traveling to the Red Planet with the Ingenuity Mars Helicopter. Together, they will enter the Martian atmosphere on Feb. 18, 2021, at 12:47 p.m. PST
(3:47 p.m. EST) and will touchdown at Jezero Crater 410 seconds later.


NASA’s Mars 2020 Perseverance rover is less than 100 days from landing. Click anywhere on the image to take the spacecraft for a spin, or view the full interactive experience at Eyes on the Solar System.

More About the Mission

A key objective of
Perseverance’s mission on Mars is astrobiology, including the search for signs of ancient microbial life. The
rover will characterize the planet’s geology and past climate, pave the way for
human exploration of the Red Planet, and be the first mission to collect and
cache Martian rock and regolith (broken rock and dust).

Subsequent missions, currently under consideration by NASA in
cooperation with ESA (European Space Agency), would send spacecraft to Mars to
collect these cached samples from the surface and return them to Earth for
in-depth analysis.

The Mars 2020 mission is
part of a larger program that includes missions to the Moon as a way to prepare
for human exploration of the Red Planet. Charged with returning astronauts to
the Moon by 2024, NASA will establish a sustained human presence on and around
the Moon by 2028 through NASA’s Artemis lunar exploration plans.

JPL, which is managed for NASA by Caltech in Pasadena,
California, built and manages operations of the Perseverance rover.

For more about Perseverance:

mars.nasa.gov/mars2020/

nasa.gov/perseverance

For more information about NASA’s Mars missions, go to:

https://www.nasa.gov/mars

News Media Contact

DC Agle
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-9011
[email protected]

Grey Hautaluoma / Alana Johnson

NASA Headquarters, Washington

202-358-0668 / 202-358-1501

[email protected] / [email protected]

2020-223