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by Bill Taylor and Bill Pine

INSPIRE (Interactive NASA Space Physics Ionosphere Radio Experiment - is a non-profit scientific, educational organization whose objective is to bring the excitement of observing natural and manmade radio waves in the audio region to high school students and others. The project consists of building an audio frequency radio receiver kit, making observations of natural and manmade radio waves and analyzing the data. Students also learn about NASA and our natural environment through the study of lightning, the source of many of the audio frequency waves, the atmosphere, the ionosphere, and the magnetosphere where the waves travel.

Early in INSPIRE's history, radio wave observations were made by 1000 high schools whose locations are shown on the figure.
Early in INSPIRE's history, radio wave observations were made by 1000 high schools whose locations are shown on the figure.

Our eyes are only sensitive to a very narrow range of the electromagnetic spectrum. Like the dog that can hear sounds we can't, there is a large part of the spectrum of electromagnetic waves we can not see. If we could, we would be dazzled by the distinctive sounds of natural electromagnetic emissions such as sferics, tweeks, whistlers, chorus, and many others. These are natural radio waves or emissions coming from such common phenomena as lightning, but there are also audio frequency emissions that reach the ground that come from tens of thousands of miles from us, deep in the Earth's magnetosphere, the protective tear drop shape of the Earth's magnetic field, formed by the solar wind. Natural audio frequency radio emissions and manmade audio frequency transmissions can be received, amplified and turned into sounds that we can hear.

The INSPIRE kit is designed for high school physics students or classes, but is enjoyed by adults and by students as young as ten. A new, more sensitive receiver with a lower noise level was developed in 2002 and is now available at the INSPIRE order web site at:

The receiver kit is relatively easy to assemble, using simple hand tools for mechanical construction and a soldering iron for the electronic construction. The receiver is an audio amplifier, with the input connected to a several meter long antenna. The audio amplifier has built-in filters to reject radio stations above the audio range and power line noise at the bottom end of the audio range. There are two outputs so that the receiver can be connected to headphones to listen and to a tape recorder for later analysis.

An alternative way of participating is to listen, record and analyze data from one of the two internet online INSPIRE receivers. The first is operated by NASA/Marshall Space Flight Center's National Space Science and Technology Center (NSSTC) in Huntsville, Alabama. To receive the live INSPIRE stream from NSSTC, paste

into your favorite audio player. The NSSTC data is available 24 hours per day, seven days a week.

The second online receiver is operated by the University of Florida Radio Observatory (UFRO) not far from the Suwannee River at Old Town, Florida. To receive the live INSPIRE data from UFRO, paste

into your favorite audio player. Florida is the lightning capital of the world and lightning can damage the INSPIRE receiver and the microwave link from UFRO to the University. Thus the UFRO INSPIRE data is available 24 hours per day, seven days a week, except during the lightning season, approximately July through September. The UFRO data link is also used occasionally by INSPIRE's sister project, Radio JOVE,

to send data received from Jupiter between 18 and 32 MHz over the internet. When Radio JOVE data is available, INSPIRE data is not.

If these links do not work, check the INSPIRE web site, since a URL may have changed.

INSPIRE began with a 1989 test bed project, ACTIVE/HSGS, which involved 100 high schools making observations of transmissions from the Soviet ACTIVE satellite. The second major project, in 1992, was to observe transmissions from the SEPAC electron accelerator, in which 1,000 schools participated. Subsequent projects focused on the annular solar eclipse on May 10, 1994, cooperative experiments with the Russian space station MIR from 1995 until it was deorbited in 2001, balloon flights of INSPIRE receivers during the Leonids meteor showers of 2000 and 2001, and cooperative experiments with the IMAGE satellite and the Russian school satellite, Kolibri-2000. About 1800 INSPIRE receivers have been purchased.

Underlying the objective of INSPIRE is the conviction that science, mathematics and technology are the underpinnings of our modern society, and that only with an understanding of science, mathematics and technology can people make correct decisions in their lives, public, professional, and private. Stimulating students to learn and understand science, mathematics and technology is key to them fulfilling their potential in the best interests of our society. INSPIRE also is an innovative, unique opportunity for students to actively gather data that might be used in a basic research project.

The INSPIRE Journal is issued in November and April of each year with INSPIRE news, activities and results. Subscriptions are available from the INSPIRE order web site:

INSPIRE has organized and participated in workshops nearly every year since its beginning. INSPIRE plans to hold Workshops each year. The Workshops are primarily organized by local teachers and volunteers and will offer an introduction to INSPIRE and its projects, to kit building (sometimes the students and teachers do not have the expertise to build the kits without help), to site location and data gathering procedures.

A Workshop will usually be held on a Saturday, with INSPIRE participants, both teachers and students, attending. A national INSPIRE representative will attend each Workshop as a primary presenter and resource for the participants. To inquire about a Workshop in your area, contact the leaders of INSPIRE, Bill Taylor or Bill Pine at

Many organizations have contributed to the success of INSPIRE, including NASA/Goddard Space Flight Center, NASA/Marshall Space Flight Center, Raytheon, District of Columbia Space Grant Consortium, and Florida Space Grant Consortium. We deeply appreciate their support.

Last Updated: 16 February 2011

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Last Updated: 16 Feb 2011