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Artist's Conception


EQUATOR-S is based on the small-satellite approach. It was designed and built at a research institute ( MPE Garching ) with relaxed product-assurance requirements and without high-reliability components. It has a lean project organization and management under a single Principal Investigator (PI). Still, strict adherence to sound engineering practice was observed. Thorough environmental and functional testing was done, including vibration, acoustic noise, solar-simulation, Electromagnetic Cleanliness (EMC), and magnetic tests. Outside procurement and contracts were limited to the RF-components (receivers/transmitters), thermal and structural analysis, solar-panels, and kick-motor.

EQUATOR-S carries advanced science instrumentation, but at essentially no development cost because the instruments were developed for other misions (CLUSTER, WIND).

In addition, some technological instruments are carried: a GPS receiver (picture) to investigate the utility of such a system on excentric orbits (LI: B.Eissfeller , UniBW München, Germany) and an instrument that monitors temperature, efficiency, and radiation tolerance of some novel solar cell types (picture) (LI: K.Bogus, ESTEC, The Netherlands).

A feature of EQUATOR-S that distinguishes it from all previous missions and also from the other IASTP satellites, is its high spin rate of 40 rpm. It allows unprecedented temporal resolution of those measurements which utilize the spacecraft rotation for achieving complete angular coverage, i.e., for the measurements of particle distribution functions.

EQUATOR-S is well equipped to measure the full range of bulk parameters and underlying velocity distributons of electrons and all major ion species once per 1.5 s, as well as the electromagnetic field up to frequencies of the order of 50 Hz. To keep the spacecraft small and simple, it was decided, with great regrets, not to include high-frequency measurements of the electromagnetic field which require long booms. Thus with EQUATOR-S we will be able to study the dominant dynamical processes in the equatorial plasma, but will have to omit detailed wave-particle interaction studies at high frequencies.

Last update of this page 1999-06-18 by Helmut Steinle . Please send comments to !

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