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the sound of earth song presented by

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science at nasa

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in space they say no one can hear you

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scream

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nobody ever said anything about singing

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though a nasa spacecraft has just beamed

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back a beautiful song sung by our own

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planet

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it's called chorus explains craig

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kletzing of the university of iowa this

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is one of the clearest examples we've

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nasa's twin radiation belt storm probes

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are traveling through the region of

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space where chorus actually comes from

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and the recordings are out of this world

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this is what the radiation belts would

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sound like to a human being if we had

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radio antennas for years says kletzing

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whose team at the university of iowa

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built the emphasis

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electric and magnetic field instrument

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suite and integrated science receiver

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he's careful to point out that these are

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not acoustic waves of the kind that

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travel through the air of our planet

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chorus is made of radio waves that

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oscillate at acoustic frequencies

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between 0 and 10 kilohertz the long

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antennas of the radiation belt storm

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probes are perfect for detecting these

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kinds of waves

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chorus emissions are front and center

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for the storm probe mission says

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kletzing they are thought to be one of

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the most important waves for energizing

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the electrons that make up the outer

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radiation belt

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in particular chorus might be

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responsible for so-called killer

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electrons

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high energy particles that can endanger

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both satellites and astronauts most

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electrons in the radiation belts are

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harmless with too little energy to do

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damage to human or electronic systems

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but sometimes these electrons catch a

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chorus wave like a surfer riding a wave

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on earth and gain enough energy to

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become dangerous

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the radiation belt storm probes are on a

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mission to find out for sure

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the production of killer electrons is a

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matter of much debate and chorus waves

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are only one possibility note storm

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probe's mission scientist dave cybeck

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launched in august 2012 the two probes

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are orbiting inside the radiation belts

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sampling electromagnetic fields counting

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the number of energetic particles and

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listening to plasma waves of many

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frequencies

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we hope to gather enough data to solve

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the mystery once and for all says cybeck

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at the moment the spacecraft are still

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undergoing their 60-day checkout phase

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before the main mission begins so far

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things are checking out very well

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one of the things we noticed right away

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is how clear the chorus sounds in the

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recording notes cletzing that's because

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our data is sampled at 16 bits the same

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as a cd which has not been done before

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in the radiation belts this makes the

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data very high quality and shows that

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our instrument is very very healthy

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eventually klutzing hopes to release

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unprecedented stereo recordings of

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earth's chorus we have two spacecraft

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with two receivers he says so a stereo

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recording is possible

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such a recording would not only sound

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wonderful but also have real scientific

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value

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one of the things we don't know is how

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broad the region is over which chorus

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occurs

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the widely separated stereo capability

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of the storm probes will give us the

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ability to figure this out he explains

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with a two-year mission planned for the

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storm probes the earth song is just

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getting started

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for more weird and wonderful sounds from