Voyager 1 PWS electron plasma oscillations beyond the heliopause

This animation combines two ways of displaying the Voyager Plasma Wave Science (PWS) observations of electron plasma oscillations which provide the basis for concluding that the spacecraft is now in interstellar space. The graphic is called a spectrogram that shows the amplitude of waves (in which reds are the most intense and blues the least intense) as a function of frequency (vertical axis) and time (horizontal axis). In many respects, this spectrogram is like a voice print which shows the evolution of the spectrum of sounds as a function of time. The sound track reproduces the amplitude and frequency of the plasma waves observed. The vertical white bar that moves across the spectrogram links the sound track to the graphic.

The frequency range shown from about 1.75 kiloHertz to 3.5 kiloHertz is a portion of the actual frequency range detected by PWS and is well within the audio frequency range. Importantly, the frequency is directly related to the number of electrons per unit volume in the vicinity of Voyager and corresponds to about 1 electron per 10 cubic centimeters or a cube about 1 inch on a side. The time scale for this presentation represents 225 days or a bit more than 7 months, while it only takes about 12 seconds to play the audio file. Hence, the time compression is about 1.6 million to one. It should be noted that this compression was done in such a way as to not change the frequencies.

In this animation, there are two events of interest. In the October-November 2012 time frame there is a tone near 2.1 kHz which gradually increases in frequency. Again, in the April-May 2013 time frame there is another event, somewhat more intense and at a higher frequency near 2.6 kHz. We conclude that these two events indicate an ongoing trend to higher frequencies. The second graphic frame which appears in the animation includes a dashed line showing this increase in frequency and suggests that the density of electrons is continually increasing over this time interval as Voyager moves outwards from the heliopause (which was crossed on 25 August 2012).

[DanceRhythMIX]

Thank you for explaining that, I guess this was the last clear boundary that Voyager 1 will cross in quite some time.

[naiduvga]

Now we really get to see beyond the beyond. How every edge overlaps

[Space-Audio]

The sample with the unmodified waveform is available at Voyager 1 PWS raw electron plasma oscillation audio

[jouk]

The sound of dust hitting the Voyager 1 spacecraft

[Jeffsaliesea-nr]

If Voyager 1 Passed by Neptune Can you do the audio if you can?

[piquezino]

But, if Voyager 1 is out of the solar system, why the plasma density increase ?

[SKYlightsEBE]

i have a stupid question this *plasma over the vulcanos* is there any description how  it is produced ?

[Kudrlin]

Ok, now it is really definite that the Voyager 1 crossed the heliopause? :)

[sandysandy]

I heard somewhere plasma waves are only present in the solar system.and outside solar system.its justs darkness how these waves are still present.

[DanceRhythMIX]

So this is not actually the edge of the solar system right? Beyond this point can there still be objects that orbit the sun?

[Eminonna]

Asi no suena el espacio. Asi suena el cacharro con que sintentizan y convierten en sonido ondas del espacio.

Sensacionalismo.