The franco-soviet ARCAD-3 project was launched aboard the AUREOL-3 satellite on 21 September 1981 from Pletsesk (Russia) into a quasi-polar orbit (apogee: ~2000 km, perigee: ~400 km, inclination: 82.5°, period: 109.5 minutes). The scientific payload was designed to allow detailed studies of the ionosphere-magnetosphere coupling and included a number of complementary experiments described in a special issue of Annales de Geophysique (38, N5, 1982). Detailed measurements were performed of suprathermal and thermal particles, of electrostatic waves from 0 to 16 kHz and from 0.1 to 10 MHz, of electromagnetic waves from 0 to 16 kHz, of the quasi-static electric field, and, finally, of the magnetic field variations associated with field-aligned currents.

The 3-axis stabilized AUREOL-3 satellite operated in many different telemetry configurations, (a) direct, high bit rate, real time telemetry, transmitted to various ground stations mostly located at high latitudes (Tromsö /Norway , Apatity/Russia , Terre-Adélie/ French Antarctica , Kerguelen Islands/Indian Ocean), or (b) onboard recording over interesting geophysical regions, and subsequent transmission to ground stations. Most of the useful AUREOL-3 data was obtained during the 18 first months of its scientific lifetime (that is, from November 1981 to June 1984) and are presently archived at CNES, Toulouse. It must be noted that AUREOL-3 died in July 1987. A few scientific sequences were recorded after June 1984 but not presently included in the present database. So that, more than 800 sequences are directly accessible, each archived scientific SEQUENCE corresponding to either:

(a) high bit rate data directly recorded at auroral or polar telemetry stations (mostly, Tromsö, Norway, and Terre-Adélie, Antartica). The duration of such archived auroral and/or polar passes is generally ~10-20 minutes.

(b) Data recorded onboard. The bit rate and duration of such recordings may be highly variable, from ~10 min. to ~110 min. (orbit duration).