"New Sound on Mars": NASA's rover captures helicopter flight sound
New Delhi : NASA's Perseverance rover has for the first time recorded a low-pitched whirring of the Ingenuity helicopter's blades as it takes a flight on Mars' rarefield.
The space agency has released a video showing its six-wheeled robot of its rotorcraft companion making its fourth flight on April 30 -- this time accompanied by an audio track.
The three-minute-long video starts with a rumble of wind blowing then shows how sound of the helicopter changes as it takes a flight in the environment. Check out the video below:
Ingenuity takes off, and its blades can be heard humming softly as they spin at nearly 2,400 rpm on the 872-foot (262-meter) roundtrip.
The scientists were not sure if they would be able to capture any sound from the helicopter as it was parked around 277-meters away. But what happened, it gives new dimension to the research.
The Martian atmosphere is about one percent the density of our planet's, making everything much quieter than on Earth.
"This is a very good surprise," said David Mimoun, a professor of planetary science at Institut Superieur de l'Aeronautique et de l'Espace (ISAE-SUPAERO) in Toulouse, France, and science lead for the SuperCam Mars microphone.
"We had carried out tests and simulations that told us the microphone would barely pick up the sounds of the helicopter, as the Mars atmosphere damps the sound propagation strongly," he added.
Apart from having a lower volume, sounds emitted on Mars travel slower than they do on Earth, because of cold temperatures, which average -81 degrees Fahrenheit (-63 degrees Celsius) on the surface.
The speed of sound on the planet is therefore around 540 mph (roughly 240 meters per second), compared to about 760 mph (roughly 340 meters per second) here.
