Solar Wind Sonification

How tranquil the soul that weeps to the sound
of musical interface from starlight unbound
Each gentle refrain brings me closer to where
the solar wind breathes round the suns mystic flare
The touch of its breath ignites passionate soul
Like the stroke of each note on a piano of coal
Composed inner space drifts so sensuously
Towards all it creates in engaged rhapsody
The flow of its dust brings more ancient design
To rain down on earth and once there to combine
With the knowledge of all that once was and is now
Like a lovers first kiss on the cusp of stars plough

[This is an original poem written by V.N.McCabe for SOLAR WIND.]

If you copy the poem please quote the author's name. Thank you.

The visual element of this piece is an attempt to capture the sheer
magnitude of the events taking place in the music, the same events
which are occurring in space at this very moment. There are still
many mysteries behind the solar cycle, and this project seeks to
further our understanding through an interpretive process known as
Sonification.

The music is driven by solar wind data that was captured by the ACE
satellite during the year 2003. The sweeping wind sound is generated
by both He++ density and velocity. Velocity controls the cutoff
frequency of a band-pass filter that has been placed over pink-noise,
this causes the whooshing sound that sweeps up and down. Density
controls the loudness of this wind sound, the higher the density the
louder the wind. During a Coronal Mass Ejection the wind is further
amplified and processed with a form of distortion known as overdrive.
This causes the wind to swell in a more violent fashion. The basic
vocal ambience layer is created with 6 distinct vocal layers that
correspond to carbon charge state distribution. The value average
charge state of Carbon is represented by another set of voices that
sing in a higher register. The He/O element ratio is represented by a
chord composed of an extremely high frequency set of triangle
waveforms. This sound can be described as a glistening. During a
CME the reverb quickly swells to a much higher volume before slowly
receding back to the baseline level, this creates the feeling of a
sudden expanse.

The playback speed of the data is scaled such that the rotation of the
sun lines up precisely with the music. The tempo is 150 beats per
minute, and a full Sidereal Carrington rotation (25.38 days) taking
place every 8 measures. With this kind of mapping, any patterns in
the data that occur in a periodicity consistent with the Carrington
rotation will consistently fall in the same place in relation to the
beat.

Video clips have been arranged such that auditory events often
correspond visually to solar flares or CME events.

By Robert Alexander at http://robertalexandermusic.com/. Science and instrument descriptions at http://solar-heliospheric.engin.umich.edu/.