My voice will be quieter and deeper than what you hear on Earth, and you'll need to wait longer to hear it. But the biggest variation in sound is the treble. The noises we hear every day, such as birdsong, whistles or bells, are almost inaudible. This is due to the fact that 96% of the carbon dioxide in the Martian atmosphere absorbs the treble, leaving only a low-key rumbling sound.
So when we hear the best recording of Perseverance to date, remember that the sound you hear is from another planet. It may sound similar to sounds on Earth, but it's still the sound of a world that's 339,000 miles or 546,000 kilometers closest to us. In February 2021, four Martian days after Perseverance landed, we will hear the recordings being captured for the first time.
You will hear the rumble of dry sand and gravel in the desert world by different winds. Another benefit of connecting a microphone on a rover is that once it has completed its task, engineers can hear it so that they understand and even diagnose problems that may arise with a robot, just as a mechanic might listen carefully to the problem with the engine. In this recording, we can hear Perseverance driving in parts of Jezero Crater.
The rumbling and thumping of rovers as they weave through continuous rocky terrain can also be heard very directly. One of the big surprises of the mission was that during the fourth flight test, Perseverance heard the buzzing of the rotor of the Witty UAV. Witty took perseverance's core to Mars and was used to test the first powered flight on Mars.
If you listen carefully, the faint hum of the helicopter can be heard above the sound of the Martian wind. 380 million years ago, the Red Planet was wet and probably even habitable to us. Today's Mars is a barren desert world, inhabited only by robots, at least for now. We may not hear the sound of water flowing through the red rocks, but you still hear the sound of an exoplanet and a robot exploring it.
Since the 1960s, we have set up numerous projects for Mars to learn more about our red-faced neighbor. We have made many incredible discoveries on this barren planet, the highlight of which is that Mars, perhaps a planet full of flowing water 3.8 billion years ago, was as habitable as Earth, but now it has dried up. But as time passed, dramatic changes caused the oceans and lakes on Mars to disappear. Today, there is no liquid water, but is full of quicksand, eroding dry rocks, and everything is shrouded in a thin and cold atmosphere.
We've almost all seen photos sent back through Mars rovers and landers, but now we have the opportunity to enjoy the human feel on Mars, where NASA's Perseverance rover is able to not only observe the Martian environment, but also receive ambient sounds. Perseverance carried two custom commercial microphones. One of the microphones is installed inside it and is used when entering Mars, landing on the descent. The other is installed in a camera called the SuperCam, which can extend its long arms to observe Martian soil and rocks, and is equipped with a laser and mass spectrometer for detecting organic compounds related to former Martian life. Through the transmission of information from microphones, scientists were able to directly study how sound propagates in the Martian atmosphere for the first time.
Attempts to send audio-visual reception equipment to Mars have failed for many years, but now we have done little research on the sound conditions on the surface of Mars. In 2018, NASA's InSight lander used its geological sensors to capture eerie sounds on Mars, the first sound data humans have detected on the Red Planet. But compared to geological sensors, the Perseverance rover can use sensitive commercial microphones to directly capture actual audio-visual data, which allows people to hear sounds on Mars as if they were really in Jezero Crater.
The so-called sound that human beings hear is the vibration that arises from the eardrum of the human ear. This vibration comes from pressure waves generated by sound sources that need to pass through a certain medium to reach the human ear, such as air, liquids, and even solids, as is the case on Mars. The temperature, density, and composition of the Martian atmosphere are very different from those on Earth than they are on Earth, so if you don't listen to me on Mars without a helmet, I'll sound like this.
By: Easy to learn, Zhou Langyue