High-frequency Active Auroral Research Program (HAARP) is based in Alaska and it's a high-power, high frequency (HF) transmitter for studying the ionosphere. The principal instrument is a phased array of 180 HF crossed-dipole antennas capable of radiating 3.6 megawatts into the upper atmosphere and ionosphere. Transmit frequencies are selectable in the range of 2.7 to 10 MHz.
Update: Note that due to hazardous winter road conditions along the highways leading to the HAARP facility, the January Research Campaign has been delayed by 1 day. Dates updated below.
The research team have announced that they will be carrying out tests from the 28th of January to the 2nd of February 2025.
The press release is shown below and I've added a map to show location and distance.
To: Amateur Radio & Radio Astronomy Communities
From: HAARP Program Office
Subject: Notice of Transmission
The High-frequency Active Auroral Research Program (HAARP) will be conducting a research
campaign with operating times specified in the table below. Operating
frequencies will vary, but all HAARP transmissions will be between 2.75 MHz and 10 MHz. Actual
transmit days and times are highly variable based on real-time ionospheric and/or geomagnetic
conditions. All information is subject to change.
This campaign is being conducted in support of research proposals from UAF, the University of
Florida, the Naval Research Laboratory, Los Alamos National Laboratory, Cornell University,
Dartmouth College, Embry-Riddle Aeronautical University, and the University of Houston.
Research topics for this campaign include VLF generation and ducting, studies on STEVE airglow,
and space debris detection.
This campaign will also support the GIRAFF rocket launch from Poker
Flat Research Range, which is investigating the mechanisms that cause flickering and pulsing
within the aurora. More information on GIRAFF is available here:
Note that a number of experiments will be conducted based on the critical frequency (f0F2)
determined by the Gakona ionosonde. The included transmission notice supplement contains
information on the frequencies HAARP is authorized to transmit. HAARP transmissions will only
occur on our authorized frequencies.
There are no specific data collection requests from funded investigators, but reception reports are appreciated and may be submitted online via our web form
For updates on ionospheric conditions in Gakona, please consult ionograms from the HAARP
The image above is an annotated ionogram from HAARP that describes features that may be of
interest. Note that f0F2 is calculated at the top left.
f0F2 is the critical frequency of the F2 layer of the Earth’s ionosphere. This is the frequency at
which radio signals stop refracting off the ionosphere and begin passing through to outer space.
For certain HAARP experiments that deal with interactions in the ionosphere, transmission
frequencies below f0F2 are desirable, while for other experiments (such as those involving high altitude satellites), staying above f0F2 is required.
Supplement to HAARP Notice of Transmission
General Information for HAARP Radio Enthusiasts:
