I'm too dumb to even understand this. What would cause a vibration in space?

Could possibly be ice starting to heat up and things expanding as the comet comes closer to the sun

Throw a rock at your ear, and let us know if you hear anything.

A) The impact of the Spaceship on the Comet will have caused significant vibrations

B) Tiny bits of dust and rock that are constantly peppering the comet as it moves through space

C) The difference in heat of the outside and the core of the comet

D) Gravitational forces which may be forcing the rock to expand or contract depending how close it is to large bodies like planets.

E) Solar Wind

Comets have a tail, right? The tail must have gas in it, which may be enought to carry sound waves. In any case, the little article says that humans can't hear the sound.

jmo1121109, Jamiet99uk and Hellenic Riot:
The little article claims the sounds were recorded before impact.

The article has a clip of the sound. It sounds like a metronome / clicking.

ah ok JECE, I understand your point. Humans can't hear; but it was recorded and amplified.

Well, ignore A) then. The others will all still have an effect whether or not there's a great big spaceship there.

I like B. Just audibly it sounds more in line with the clip -- to me anyhow.

It's not sound like what we normally think of as there is a vacuum, and what we think of sound waves won't travel through space. We think of sound waves normally as the oscillation\movement of particles against each other (think of an bat hitting a wall, it generates a change in air pressure that sounds like a swishing noise, than a bam as it collides with the wall - but sound can be generated in other ways that don't need a medium to pass through.

The comet has a magnetic field around it (most large rocky objects do), and the unusual thing about this field is that its oscillating its frequency. This magnetic oscillation is what is being measured, and is what is unusual. They call it a 'sound' because technically all frequencies are sound, it just depends on what\who can hear them.

Wait, @ag7433. Did you say you visited the space station? In space?

Lol, I was wondering about that too :-)

Definitely not aliens.

@jmspool I'm in finance, and joined the team as an astro-accountant for their 10 year asset inventory.

@awgray so you're saying that everything emits sound?

Really, 2WL?
http://bit.ly/1vkUHaV

@ag The definition of sound in the article is misleading, no not everything emits sound.

The comet has a magnetic field - as do asteroids and anything metallic really of any size. If that magnetic field vibrates, it typically does so at a set frequency. That frequency can be graphically represented as a wave function (up and down and up and down). This frequency of the magnetic field is what the article is calling as sound.

The interesting thing isn't that it has a magnetic field, the interesting part is that it's changing and they don't know what is causing it to change.

@jmspool, the space station was built in space so it had to have been in space.

Also, only 2% of things said on the internet are made up, so what ag said sounds pretty reliable to me.