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The answer to this fascinating question may
be found on Titan, Saturn's largest moon. University of
Southampton scientist Professor Tim Leighton has speculated
how the sound of splashing liquid in deep space might differ
to that heard on Earth - and it's possible that his theory
could be proved later this year by NASA's Cassini mission to
Saturn. In the meantime, he has recreated the sound he
believes it makes and put it on the Internet.
On
Thursday 1 July 2004, NASA's Cassini space craft will go into
orbit around Saturn where it will study the planet, its moons
and rings for four years. However, in Professor Leighton's
view, possibly the most interesting aspect of the Cassini
mission, is the European Space Agency's probe Huygens, which
will study Titan. After a seven-year journey strapped to the
side of Cassini, the probe will separate from it on Christmas
Day 2004 and coast for 20 days before parachuting through the
thick atmosphere to become the first man-made object to land
on the moon of another planet on 14 January 2005.
Titan's thick smog has prevented earlier spacecraft
photographing its surface, but there are suggestions that the
moon may be home to seas and streams made, not of water, but
of liquid ethane. The main focus of Huygens' mission is
sampling the smog-laden atmosphere, but three minutes of
battery time will be used for investigations immediately after
landing. Although the probe's microphone is on board primarily
to monitor atmospheric buffering, Professor Leighton of the
University's Institute for Sound and Vibration Research, has
suggested that, were the microphone to detect a splash-down as
opposed to a crunch on landing, the question of what a splash
in space might sound like would be answered.
Professor
Leighton, who has speculated for several years on sounds in
space, explains: 'I began asking whether the noise of splashes
which is so familiar to us on Earth would be recognisable in a
sea of liquid ethane at a temperature of 180 degrees below
zero. NASA's specially-commissioned painting of a waterfall -
actually a methane fall - on Titan inspired me to attempt to
predict how it would sound. I set up the equations and
measured the sound of a small waterfall in nearby Romsey. My
colleague Dr Paul White then processed the signal to obtain
what we believe would be the sound of a methane fall on Titan.
'Given that the last decade has seen an explosion in
the amount we can learn about the oceans simply by listening
to them, from storms to seabed properties to coastal erosion,
acoustics represent a potentially exciting and comparatively
low-cost method of space exploration.'
Professor
Leighton outlines his ideas for the role of acoustics in space
exploration in an article entitled 'The Sound of Titan' to be
published in the July/August edition of Acoustics Bulletin.
The sound of the methane fall as calculated by Professor
Leighton and Dr Paul White can be heard at
www.isvr.soton.ac.uk/fdag/uaua.htm | |
