Challenges in developing the microwave instrument for the Rosetta Orbiter

The microwave instrument for the Rosetta Orbiter (MIRO) built by the Jet Propulsion Laboratory, will be launched on the European Space Agency´s (ESA) Rosetta Spacecraft in 2004. MIRO will measure the near surface temperatures of the asteroids Otawara and Siwa, and the comet Wirtanen, thereby allowing scientists to estimate the thermal and electrical properties of these surfaces. The MIRO instrument consists of two heterodyne radiometers, one operating at millimeter wavelengths (190 GHz, ∼1.6 mm) and one operating at submillimeter wavelengths (562 GHz, ∼0.5 mm). The spectrometer portion of MIRO will allow measurements of water, carbon monoxide, ammonia, and methanol in the gaseous coma of comet Wirtanen. These measurements will allow scientists to study how the comet material sublimates (changes from its frozen state, ice, to a gas) in time and distance from the sun. As an international team, significant challenges to development and integration coordination were :required to ensure instrument delivery to the European Space Agency (ESA). Additionally, the instrument, developed under NASA´s Faster, Better, Cheaper paradigm challenged the team to find new and inventive ways to achieve the scientific requirements. This paper explores the various trades, challenges, processes and programmatic issues encountered.