VOYAGER-1 PWS:
JUPITER ENCOUNTER

This video lasts 4 hours 26 minutes and requires flash or html5.

On the occasion of the 40th anniversary of the Voyager 1 Jupiter encounter, we present all available plasma wave audio data acquired during the day of closest approach. Beware: This video is almost 4 hours 27 minutes in length and includes many uninteresting stretches of data.

The PWS plasma wave instrument on Voyager 1 recorded these signals as the spacecraft made its closest approach to Jupiter on March 5, 1979. During this time interval, the spacecraft flew from a distance of about 13 Jupiter radii in front of the planet at a local time angle of about 13:00 to roughly the same distance beyond the planet at a local time angle of about 01:00.

The PWS wideband waveform instruments on the two Voyager spacecraft sample the electric field on the dipole wire antenna at a rate of 28800 4-bit samples per second, using an automatic gain control. Consequently, the audio is just slightly better than telephone quality. Packets of 1600 samples are acquired, separated by the equivalent of 128 missing samples. Running these packets together results in the playback taking less than real-time (by a factor of 1600 / 1728), and also introduces a slight audible flutter. The amplitudes at the edges of these packets have been smoothed to reduce this flutter, but this is the only modification to the signal.

The video shows a series of 48-second-wide spectrograms with an animated cursor that shows the time of the audio track. The amplitude of the signals is color coded with dark blue for the weakest and red for the strongest signals. Low frequencies are at the bottom of the plot and high frequencies are at the top. Time ranges from left to right.

See the Voyager 2 video covering the arrival at Jupiter for a discussion of the various interference signals from other onboard instruments, for example the gong-like low-frequency sounds and harmonic tones that occur fairly frequently.

For more information on the Voyager project, see
https://voyager.jpl.nasa.gov/

For more information on the Voyager plasma wave investigations, see
https://space.physics.uiowa.edu/voyager/

For more information on space audio, see
https://space-audio.org/

The audio and video are available under a Creative Commons Attribution 3.0 Unported License, with clear citation.
Shift-click the following links to download the AVI video or just the mp3 audio
https://space.physics.uiowa.edu/voyager/V1PWS_Jupiter_1979-03-05T0000-2359.avi
https://space.physics.uiowa.edu/voyager/V1PWS_Jupiter_1979-03-05T0000-2359.mp3