Mean Free Path to Insanity

*Quick note: The majority of my work is not based on calculations, but it is really important to me to make sure that there is sound on the satellites I’m asserting there is sound on. It just so happens that answering that question is a bit harder than I thought, and not being a scientist I have to both learn a lot and be extremely critical of myself to put a valid argument fourth.

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Consumer science is amazing, but space research as I'm experiencing it seems to come in two flavors: super accessible and hardcore professional. I'm realizing the type of science I can digest is nowhere near what I need to make meaningful conclusions. As I get closer to the real science, it's getting harder to circumvent the fact that I don't have sufficient knowledge of space physics to make the proofs I need to make. (cue Brittany Speakers “I’m not a girl, Not Yet a Woman”)

But they don’t call me Anna “Seriously you need to sleep more than four hours a night” Brooks for nothing.

So I sat down today at 6PM to see if I could teach myself enough basic physics to definitively answer an extremely simple question: is there sound on Enceladus.

There are two parts to this question as far as I'm concerned:

1. Is there a dense enough atmosphere on the moon for waves above 20,000hz to travel.

2. Is the pressure high enough for a human ear to hear it.

I’ve been at this for eight continuous hours.

This was my reaction to finding out at hour 3.

So there is, by conservative standards, a great enough density of molecules in the atmosphere to propagate frequencies from an ultrasonic level all the way up to 30,000Hz! That’s way more than humans can hear.

Furthermore, humans can hear sounds in near-vacuum conditions, so even in a trace atmosphere it's reasonable to assume we would be able to hear.

But I didn’t trust my math. Because I'm a critical fuck and nobody should trust my math. So I did it about 19 more times and my answers seemed to indicate that even in EXTREMELY sparse atmospheres sound should be able to propagate in the range of human hearing. Which I was wary of becuase it seemed too promising, but then again I’ve never hung out in a partial vacuum (link to the equation I used here: http://hyperphysics.phy-astr.gsu.edu/hbase/Kinetic/menfre.html#c4)

So I searched, read, and parsed research Googling every other word until I had developed a pages-long directory of terms and a whole new set of notes updating my hypothesis on Enceladus.

I know for a fact that geysers make sound on Enceladus because I know how much matter is released into the air and at what speeds. From that information I can extrapolate that the molecules in the air MUST (like, absolutely must) be closer together on average than 17 m (the length of the lowest frequency perceptible by humans)… but I still deeply mistrust my conclusion that the whole planet can propagate the whole spectrum of human hearing.

It just seems too good to be true.

These calculations are going to be a lot easier with Titan and Io because we know a lot more about their atmospheres, but good golly Enceladus is throwing me though loop.

I’ve contacted a space scientist, a rocket engineer and an acoustician for help.