“In space, no one can hear you scream.”
Now classic catchphrases (from alien, One of the biggest science fiction horror films ever made) rests on the big assumptions that most of us make. The space is empty. And that’s – most of the time. But there teeth There’s plenty of stuff between the stars and in some cases enough to make a little noise.
So maybe we need to fix that line. In the universe, no one can hear you scream.
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What we consider to be “sound” is actually vibrations that move through some kind of material (what we call scientists). The music I’m listening to now when I write these words is the very vibrations created by electricity passing through the magnets in my computer speakers. The magnet pushes against the ambient air and drives a membrane that swings rapidly back and forth. This creates a wave that is usually called a sound wave, but more technically known as a sound wave. And finally, in my inner ear, another membrane responds and vibrates, sending signals to my brain, interpreting them as music.
Sound waves pass through the medium by slamming atoms or molecules within it against each other in a continuous manner. In my music, the medium is air, but I can also hear sounds underwater. Waves move these materials a little differently in air due to differences in composition and density, but the principle is the same.
If the space is really empty – it’s totally vacuum and there’s no problem – yes, alien The slogan is definitely correct. And in general, that’s true. By human standards, space is largely alive to its reputation.
However, human standards are not a major basis for comparison. Understanding why requires numerical thinking in the basic order of the amounts of sounds worn in the universe. Let’s use the term “particle” as a general term for this material. You can refer to any type of material unit, such as atoms, molecules, and subatomic particles.
With that in mind, ask: how much is the sky in the sky? For example, a laboratory vacuum chamber may contain trillions of particles per cubic centimeter, or CM.3 (about a quarter of a typical six-sided die). It may seem like a lot, but it is millions or even millions of times less particle density than the air you are breathing. A few fifty billion Molecules per cm3.
But while it may be as relatively empty as the vacuum in that lab, the space looks like soup. Interplanetary space is much rarer, with only a few dozen particles per cubic centimeter. Its thin gr can reach over 1 million grains per cm3 If the sun blows away the sun’s stormyet, other than just a handful of ultra-high vacuum cleaners achieved on Earth, it’s not that substantial.
And the interstellar space – interstellar medium – is even thinner, with only 100 particles per cubic one particle. meter (m3), or on average, 0.0001 per cm3. Intergalactic space intergalactic space has an average of one (one!) particles in the true deep space between the galaxies.3. Scream everything you want. No one hears your voice that.
I am grateful that not all spaces are evacuated equally now. In Nebras and other celestial areas, material is thicker. Typical density of beautifully lit gas clouds like the Orion Nebula is about 10,000 particles per cm3. However, the density elsewhere can be quite high. For example, Bernard 68 is a small, cold, dense molecular cloud with about 1 million particles per cm.3. This is much lower than a lab grade vacuum, but can add up even very low particle densities beyond the vast expanse of space, so the Bernard 68’s lean material is sufficient to essentially absorb all the light that otherwise passes through. Some giant molecular clouds have dense cores It could spike to 1 billion particles per cm3.
Still, your screams won’t go far. There are not enough particles to bump into each other to transport sound waves. If you want to move the sound through space, Many Larger sources that work beyond enormous amounts.
For example, an explosive star will blow up a large amount of material into space at extremely high speeds. The emissions slam the majority of the interstellar medium very hard, and enough particles will bump into each other, creating sound waves.
The velocity of the wave depends on the density of the medium, A typical nebula is about 10 kilometers per second (km/s). This is quick for our land as it is much faster than the speed of sound below 1 km/s in the Earth’s air. However, the material from the exploding star leaves it (so to speak) in the dust. It literally cultivates the surrounding gas at supersonic speed. This creates shock waves, like fighter jets that emit the sonic boom. The surrounding material around the exploding star is compressed by shock waves, creating a lovely filament and gas ribbon that is often found in clouds of expanding debris of supernovas.
A little surprising, the speed of nebulae sound has proven to be more than just an inexplicable astrophysics problem, but important to our presence here. When a dense mass of gas and dust in the molecular cloud collapses, it flattens and forms itself into a disc around the newly formed star. Very rough estimates of typical density Such a disk is hundreds of trillion particles per cm.3is more dense than the lab vacuum, but is very diluted compared to, for example, air. I think it would be considered “space”, but it’s still enough to maintain important sound waves. If the material is dense enough, it becomes viscous and even turbulent, and the mass of material gradually grows onto the planet. These conditions depend on the speed of sound within the disc, and without them the particles there tend to orbit the stars without producing planets.
In other words, without the sounds of space, we probably wouldn’t be here to talk about sounds in space. It may go against traditional wisdom, but I am willing to yell enough to let my voice heard about it.
