Re: Sound in Space

 Posted on 4/4/1994 by jmsatb5@aol.com to rec.arts.sf.tv.babylon5.moderated


Here's an interesting new element to throw out. I've taken the
time to call in some folks who know this stuff better than I do -- folks
involved in the space program, who've been willing to do a little free
work/research/thought -- and have asked them to *really* go over this
whole sound in space issue. What I've gotten back is interesting.

One of the questions I asked if, "If you're 100 feet away from a
large ship that explodes, will you hear anything?" The first answer I
got back was, "Depends on who the "you" is that we're talking about. If
by "you" you mean the tympanic membrane in your ear...no, because you'll
be dead, killed in the explosion at that kind of range."

But if we're talking about the microphone...things get different.

Ships contain atmosphere. The bigger the ship, the greater the
volume of atmosphere. Now...a ship explodes. Inside the ship, you can
definitely hear it. The hull ruptures. The atmosphere blows out in all
directions. Within the range of that atmosphere, before it dissipates
(which would be very fast), *you will hear sound in space*. For as long
as that atmosphere bubble extends. You'll also hear objects whizzing
past you within that curtain (provided that they're not moving past the
speed of sound). Then, very quickly, it'll fizzle out.

To the camera's POV, then, what you get is a sequence: flash, sound
within a VERY limited range depending on the volume of air in the ship,
quick whizz and quick fizz.

Then silence. Obviously, any ship beyond that range exploding will
be silent.

On the second question, "Could you hear a ship passing by?" there
were also interesting responses. In order for a ship to move through
space, it has to be pushing out some sort of medium to propel it
forward. If that medium is in any way gaseous, and you pass directly
in its wake, you have the same situation as the explosion: limited
sound. But you can't hear it from the side, or in front of the ship.
And again, it's *very* short range, only within the residual gases being
emitted. Though there might be a shockwave effect if a ship passes your
ship in VERY close proximity.

We're still getting some opinions on this from other experts, but
this seems to be kind of a growing consensus. All of which I find very
interesting. The sound-in-space issue has become something of a
shibboleth among SF fans...if it's there at all, it means someone's being
sloppy. But the way it's shaping up, this may not be an either/or issue,
dead silence or full sound. I'll post more on this later, but thought
y'all might like a preliminary report on this issue.

jms