Science Background

Scientists first became aware of the ionosphere when they noticed it acted as a reflector for radio waves in the early twentieth century. In the 1930's, Sydney Chapman theorized that an "electrically conducting layer" was needed to account for radio propagation experiments. These were later differentiated as the D, E, and F layers of the ionosphere - visualized as a stack, one upon the other. Later they were seen more accurately as spheres within spheres.

Current research recognizes that atmospheric regions are not independent domains, but an intermixed, mutually coupled and complex system. The TERRIERS mission will help us better understand the changing nature of this important atmospheric system.

Mission Background

TERRIERS is part of NASA's Student Explorer Demonstration Initiative (STEDI), administered by the University Space Research Association (USRA). STEDI addresses the challenge of making orbital science accessible to students as well as the challenge of developing a new class of science satellites at 5 - 10% the cost of the lowest cost NASA science missions of that era.

Boston University was chosen as one of six recipients, out of a field of 66, for $160,000 in Phase I funding in 1994. In 1995, Boston University was awarded $4.1 million in Phase II funding for construction, launch, and operation of the satellite. Funding was awarded on the basis of three principal criteria: probability of mission success, scientific or technological importance, and student involvement.

TERRIERS stands for Tomographic Experiment using Radiative Recombinative Ionospheric EUV and Radio Sources. It was named in honor of Boston University's mascot, the terrier.

Since the inception of the project, more than sixty undergraduate and graduate students at Boston University have been involved in the science, theory, design, instrument development, and testing of the satellite. A team of undergraduate student operators will control and monitor the satellite as it passes over Boston twice a day in its sun-synchronous orbit.