Abstract :
The wave complex ELISMA aboard the MARS-96 spacecraft was proposed and built by an international consortium involving nine institutes from seven European countries. ELISMA is the main dedicated wave instrumentation of the mission, although the on-board magnetometer part of the MAREMF experiment will carry out other specific and complementary measurements, and the RLK radar will record passive HF waves. Several antenna sets dispatched on different booms and wave analyzers provide a frequency range from a fraction of Hz to almost 2 MHz for the electric field and up to 2 kHz for the magnetic field. After the pioneer investigation of natural waves in the Martian environment made by the PHOBOS spacecraft, this mission offers the first opportunity of carrying out precise measurements within a much wider frequency range, in a shorter time and with better frequency resolution, a deeper exploration down to the ionospheric level and over a much longer time in orbit, thus making it possible to study latitudinal, diurnal and seasonal variations. In addition to measuring natural waves and plasma instabilities, ELISMA will carry out precise measurements of thermal plasma using active modes of several sensors and antennae. The absolute electron density and thermal energy will be obtained using the mutual impedance technique and high-frequency antennae; the Langmuir probes will record complementary measurements of abrupt variations in these quantities. They will monitor the spacecraft potential and carry out a survey of the UV solar flux. This paper introduces the consortium participants, describes successively the different parts of the ELISMA experimentation and their dedicated scientific objectives, and outline certain aspects concerning the flight operations and data handling.
