Back in 2005, an advanced probe named Huygens began plummeting through the thick clouds
of Saturn's largest moon, Titan. Huygens is a European space agency probe that
travelled for seven years attached to the side of NASA's famous Cassini spacecraft,
with the goal of studying the solar systems most Earth-like world.
Titan is an icy moon, that is shrouded by a hazy, golden atmosphere, which obscures
its mysterious, frigid surface. It is the second-largest moon in the solar system, even
larger than the planet Mercury and is the only world besides Earth to have standing
bodies of liquid, including rivers, lakes and seas.
Its thick atmosphere is primarily made up of nitrogen, with a hint of methane, and its
surface is bitterly cold, dropping to around -290 degrees Fahrenheit, which is -179 degrees
Celsius. It is so cold here that water is frozen harder than rock.
When the Huygens probe separated from Cassini and began its treacherous journey towards
Titan, no one knew what to expect. Would it plunge into an ocean of liquid methane? Crash
into jagged ice mountains? Or perhaps sink into a pit of frozen
hydrocarbon quicksand. What could be found below these opaque clouds was largely a mystery
and so Huygens had to be prepared for anything. It took the probe two hours and 27 minutes
to parachute through the giant moons thick atmosphere, which extends out more than 6
times further into space than Earths does, before touching down on what resembles a dried-up
lakebed or flood plain, as this incredible image reveals.
Before Huygens began studying the moons icy surface, however, it first collected data
from the atmosphere during its long descent. Among a payload of scientific instruments,
Huygens was equipped with a microphone that recorded the noisy sound of wind rushing by
the probe as it passed through the moons golden coloured haze. Allowing the listener to hear
what it would sound like if you were able to sky dive through the clouds of Titan.
So sit back, plug in your headphones and immerse yourself into a soundscape that was recording
on another world billions of miles away. In order to create this incredible 1 minute
and 43 second recording, several audio samples, that were taken at different times during
the 2 hours, 27 minute descent, were processed and combined to give a realistic reproduction
of what you would hear, if it were possible for you to fall through Titans atmosphere.
The microphone was apart of the Atmospheric structure instrument, and was originally designed
to help track down lightning by listening for the clap of thunder. Unfortunately, a
thunderstorm was not recorded, but the sound of Titans wind rushing past the probe, was.
The microphone was positioned on the outside of Huygens, so that it could record the full
force of the atmosphere as it whizzed past and so the sound that you just listened to
is similar to if you were to hold a microphone outside of a moving car for example.
Another point of the experiment was to use the sound to see how the pressure of Titans
atmosphere changes with depth. This can then be used to help build a circulation model
of the moon, similar to the ones we use on Earth to forecast the weather and understand
changes in climate. The recording itself may not seem that exciting
to listen to or even feel that alien, but it is the real sound of a mysterious world
billions of miles away, And it really does provide you with a sense of what Huygens had
to endure as it plunged through the moons golden smog.
When Huygens landed on Titan, it continued to relay data and images from the moons muddy
surface for around 70 minutes, before it lost communication with Cassini and its batteries
died. Becoming apart of this strange moon forever.
Huygens achieved many things, such as becoming the first human made object to land in the
outer solar system, It contributed important data that allowed scientists to understand
Saturn's largest moon that little bit more and it gave us the chance to view another
world like never before. The incredible probe saw, sampled and touched
one of the solar systems most unique moons, lifting its veil and allowing us to observe
its frigid, sculpted surface and listen to its alien atmosphere for the first time in
human history.