Project Inspire

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Project Inspire

• Radio
• To The Extreme!!

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What Is Project Inspire?

• Project Inspire is a group of people who listen
  to very low frequencies transmitted from the
  upper atmosphere. These range from man-made radio
  signals from satellites to natural occurrences
  like lightning or meteor showers.

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What does Inspire mean?
 

• Inspire stands for Interactive NASA Space Physics
  Ionosphere Radio Experiments

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How did Inspire get started?

• Inspire was started in 1989 by NASA to monitor
  transmissions from the ACTIVE satellite.
• NASA asked high schools to help listen to the
  radio signals.
• The students heard a bunch of other interesting
  things as well.

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What does one actually hear?

• The sounds heard were radio transmissions from
  various events. There are a few basic types.

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Sferics

• The most common type of sound heard is a sferic.
  Sferics are emitted by lighting and can be heard
  at a huge distance several thousand kilometers.
  They sound like bacon frying and are the skinny
  vertical lines on the graph.

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Tweeks

• Tweeks are sferics that have traveled over a
  great distance, as far as 20,000 kilometers. As
  the signals travel that great distance, they
  disperse a little and the high frequencies a wee
  bit before the lows. They sound like the musical
  ricochet of bullets in the movies. They are
  vertical lines with a bit of a hook at the top.

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Whistlers

• Whistlers occur when the frequency goes out into
  space and is pulled back. The dispersion present
  in tweeks is magnified and they are the hooks on
  the frequency graph. They make the sound of a
  musical note descending over the course of a
  second or more.

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Other whistlers

• There are multiple types of whistlers.

A whistler that has returned over a single
magnetic field line makes a much clearer note and
has a more defined presence on the graph.
Diffuse whistlers are those that scattered in
space and returned in bits and pieces. They are
harder to see and make a breathy, swooshy sound.
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• Two hop whistlers are those that originated near
  the listening site but still shot into space.
  They are heard both as a sferic and as a whistler
  briefly thereafter.

Whistler echo trains are those that bounce around
between magnetic conjugate points in space. Each
time they bounce, enough energy flies off to be
heard as a whistler.
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Other common sounds
LORAN is navigational signal used by the Coast
Guard. It is lots of rapid low clicks.
Chorus is a sound like birds calling heard in the
early morning caused by lots of very quick
continuous whistler-like emissions.
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What I want to do

• After learning how to use the receiver equipment,
  my biggest hope is to figure out how to link what
  I hear to events happening in the real world.I
  also hope to be able distinguish between lighting
  and other natural events like earthquakes,
  meteors, etc.