Showing posts with label Planetary Boundary Layer. Show all posts
Showing posts with label Planetary Boundary Layer. Show all posts

Tuesday, March 29

Speed of Sound on Mars



Scientists have confirmed the speed of sound on Mars, using equipment on the Perseverance rover to study the red planet's atmosphere, which is very different to Earth's.

What they discovered could have some strange consequences for communication between future Martians.

The findings suggest that trying to talk in Mars' atmosphere might produce a weird effect, since higher-pitched sound seems to travel faster than bass notes. Not that we'd try, since Mars' atmosphere is unbreathable, but it's certainly fun to think about!

From a science perspective, the findings, announced at the 53rd Lunar and Planetary Science Conference by planetary scientist Baptiste Chide of the Los Alamos National Laboratory, reveal high temperature fluctuations at the surface of Mars that warrant further investigation.

The speed of sound is not a universal constant. It can change, depending on the density and temperature of the medium through which it travels; the denser the medium, the faster it goes.

That's why sound travels about 343 meters (1,125 feet) per second in our atmosphere at 20 degrees Celsius, but also at 1,480 meters per second in water, and at 5,100 meters per second in steel.

Mars' atmosphere is a lot more tenuous than Earth's, around 0.020 kg/m3, compared to about 1.2 kg/m3 for Earth. That alone means that sound would propagate differently on the red planet.

But the layer of the atmosphere just above the surface, known as the Planetary Boundary Layer, has added complications: During the day, the warming of the surface generates convective updrafts that create strong turbulence.  READ MORE...