HAARP [High Frequency Active Auroral Research Program]

Mar 26, 2011
The High Frequency Active Auroral Research Program (HAARP) is an ionospheric research program jointly funded by the US Air Force, the US Navy, the University of Alaska and the Defense Advanced Research Projects Agency (DARPA).[1] Its purpose is to analyze the ionosphere and investigate the potential for developing ionospheric enhancement technology for radio communications and surveillance purposes.[2] The HAARP program operates a major Arctic facility, known as the HAARP Research Station, on an Air Force owned site near Gakona, Alaska.

The most prominent instrument at the HAARP Station is the Ionospheric Research Instrument (IRI), a high power radio frequency transmitter facility operating in the high frequency (HF) band. The IRI is used to temporarily excite a limited area of the ionosphere. Other instruments, such as a VHF and a UHF radar, a fluxgate magnetometer, a digisonde and an induction magnetometer, are used to study the physical processes that occur in the excited region.

Work on the HAARP Station began in 1993. The current working IRI was completed in 2007, and its prime contractor was BAE Advanced Technologies.[1]

As of 2008, HAARP had incurred around $250 million in tax-funded construction and operating costs. HAARP has also been blamed by conspiracy theorists for a range of events, including numerous natural disasters.

Research

HAARP's main goal is basic science research of the uppermost portion of the atmosphere, known as the ionosphere. Essentially a transition between the atmosphere and the magnetosphere, the ionosphere is where the atmosphere is thin enough that the sun's x-rays and UV rays can reach it, but thick enough that there are still enough molecules present to absorb those rays. Consequently, the ionosphere consists of a rapid increase in density of free electrons, beginning at ~70 km, reaching a peak at ~300 km, and then falling off again as the atmosphere disappears entirely by ~1000 km. Various aspects of HAARP can study all of the main layers of the ionosphere.

The profile of the ionosphere, however, is highly variable, showing minute-to-minute changes, daily changes, seasonal changes, and year-to-year changes. This becomes particularly complicated near the Earth's poles, where a host of physical processes (like auroral lights) are unlocked by the fact that the alignment of the Earth's magnetic field is nearly vertical.

On the other hand, the ionosphere is traditionally very difficult to measure. Balloons cannot reach it because the air is too thin, but satellites cannot orbit there because the air is still too thick. Hence, most experiments on the ionosphere give only small pieces of information. HAARP approaches the study of the ionosphere by following in the footsteps of an ionospheric heater called EISCAT near Tromsø, Norway. There, scientists pioneered exploration of the ionosphere by perturbing it with radio waves in the 2–10 MHz range, and studying how the ionosphere reacts. HAARP performs the same functions but with more power, and a more flexible and agile HF beam.

Some of the main scientific findings from HAARP include:

1. Generation of very low frequency radio waves by modulated heating of the auroral electrojet, useful because generating VLF waves ordinarily requires gigantic antennas
2. Production of weak luminous glow (below what can be seen with the naked eye, but measurable) from absorption of HAARP's signal
3. Production of extremely low frequency waves in the 0.1 Hz range. These are next to impossible to produce any other way, because the length of a transmit antenna is dictated by the wavelength of the signal it is designed to produce.
4. Generation of whistler-mode VLF signals which enter the magnetosphere, and propagate to the other hemisphere, interacting with Van Allen radiation belt particles along the way
5. VLF remote sensing of the heated ionosphere

Research at the HAARP includes:

1. Ionospheric super heating
2. Plasma line observations
3. Stimulated electron emission observations
4. Gyro frequency heating research
5. Spread F observations
6. High velocity trace runs
7. Airglow observations
8. Heating induced scintillation observations
9. VLF and ELF generation observations [4]
10. Radio observations of meteors
11. Polar mesospheric summer echoes: PMSE have been studied using the IRI as a powerful radar, as well as with the 28 MHz radar, and the two VHF radars at 49 MHz and 139 MHz. The presence of multiple radars spanning both HF and VHF bands allows scientists to make comparative measurements that may someday lead to an understanding of the processes that form these elusive phenomena.
12. Research on extraterrestrial HF radar echos: the Lunar Echo experiment (2008).[5][6]
13. Testing of Spread Spectrum Transmitters (2009)
14. Meteor shower impacts on the ionosphere
15. Response and recovery of the ionosphere from solar flares and geomagnetic storms
16. The effect of ionospheric disturbances on GPS satellite signal quality




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