"In space, no one can hear you scream"
We all know the quote and we all know that its true. Right? No air = No sound = Silence.
Except space isn't really airless. There's lots of hydrogen, some helium, a little oxygen, nitrogen etc. just floating about taking in the view. I mean, it's not like I could go for a bracing early-morning walk through it, but there is stuff there.
And sound is just molecules bouncing off each other. Admittedly, on Earth the molecules don't have to go very far to bounce of a neighbour. About 70 nanometres on average, which means it's like a bloody mosh pit in here.
So as you'd expect, it doesnt take much effort to encourage them to push each other around. Just play something by, say, Discharge and they'll be bouncing around like... well, a packed mosh pit listening to hardcore punk.
"What about in space though?" I hear you ask1. The atoms and molecules that make up the interstellar medium2 are much further apart and so take much more energy to transmit any vibrations.
So not suitable if you want to have a conversation. Or breathe. Or keep your tears from boiling and freezing at the same time.
But just because we can't hear it, doesn't mean it isn't there3. Even if we can't hear it, we can see it.
Author: NASA, ESA, and R. Sahai
The star at the tip of the arrowhead is a large, young star that has been ejected from it's origin, probably when it's binary companion went supernova. It is now travelling at a very high speed relative to everything around it and is also giving off huge amounts of light and mass as solar wind.
This is compressing the interstellar medium in front of it so much that it can't get out of the way and is forming what is know as a 'bow shock'. Basically, the star above is doing this...
[video=youtube;kpidjPVFkjM]https://www.youtube.com/watch?v=kpidjPVFkjM[/video]
Author: Unknown
The interstellar medium has a speed of sound and as a result, a sound barrier. And if you're big, bright and fast enough, you can break it4.
So if you're a million mile wide, octillion tonne star ripping through the galaxy at 100,000 miles an hour, everyone can hear you scream5.
Space is Awesome.
Sean
1. Oh? You didn't ask? Ah.
2. No, not spacefaring psychics. Also, should that be 'media'?
3. Yes, the tree does make a sound.
4. Nothing. I just like footnotes.
5. "Wheeeeeeeeeeeee!"
We all know the quote and we all know that its true. Right? No air = No sound = Silence.
Except space isn't really airless. There's lots of hydrogen, some helium, a little oxygen, nitrogen etc. just floating about taking in the view. I mean, it's not like I could go for a bracing early-morning walk through it, but there is stuff there.
And sound is just molecules bouncing off each other. Admittedly, on Earth the molecules don't have to go very far to bounce of a neighbour. About 70 nanometres on average, which means it's like a bloody mosh pit in here.
So as you'd expect, it doesnt take much effort to encourage them to push each other around. Just play something by, say, Discharge and they'll be bouncing around like... well, a packed mosh pit listening to hardcore punk.
"What about in space though?" I hear you ask1. The atoms and molecules that make up the interstellar medium2 are much further apart and so take much more energy to transmit any vibrations.
So not suitable if you want to have a conversation. Or breathe. Or keep your tears from boiling and freezing at the same time.
But just because we can't hear it, doesn't mean it isn't there3. Even if we can't hear it, we can see it.
Author: NASA, ESA, and R. Sahai
The star at the tip of the arrowhead is a large, young star that has been ejected from it's origin, probably when it's binary companion went supernova. It is now travelling at a very high speed relative to everything around it and is also giving off huge amounts of light and mass as solar wind.
This is compressing the interstellar medium in front of it so much that it can't get out of the way and is forming what is know as a 'bow shock'. Basically, the star above is doing this...
[video=youtube;kpidjPVFkjM]https://www.youtube.com/watch?v=kpidjPVFkjM[/video]
Author: Unknown
The interstellar medium has a speed of sound and as a result, a sound barrier. And if you're big, bright and fast enough, you can break it4.
So if you're a million mile wide, octillion tonne star ripping through the galaxy at 100,000 miles an hour, everyone can hear you scream5.
Space is Awesome.
Sean
1. Oh? You didn't ask? Ah.
2. No, not spacefaring psychics. Also, should that be 'media'?
3. Yes, the tree does make a sound.
4. Nothing. I just like footnotes.
5. "Wheeeeeeeeeeeee!"
