May 3, 1996. Copyright, 1996, Graphic News. All rights reserved

EUROPEAN SATELLITE LAUNCHER READY FOR TAKE-OFF
By Laura Spinney, Science Editor

LONDON, May 3, Graphic News- Ariane 5, Europe's newest satellite launcher, is due to take off for its maiden flight from Kourou in French Guiana at the end of May. The date was set after a rehearsal of the launcherÕs countdown procedure at Europe's spaceport went according to plan last Friday.

On its first trip into space, the 51-metre launcher, which has taken European scientists ten years to develop, will carry a stack of four identical satellites into geostationary orbit. The combined thrust of its three power units at lift-off will exceed 1,200 tonnes Ð more than ten times the thrust of ConcordeÕs jet engines Ð and it is capable of carrying much heavier satellites than its predecessor, Ariane 4. The four ÔClusterÕ satellites have a combined mass of 4.8 tonnes, yet Ariane 5 is capable of ferrying up to 6.9 tonnes into geostationary orbit.

Once released into orbit, the four Cluster satellites will fly in tetrahedral formation high above the equator and travel both inside and outside the EarthÕs magnetic field. For two years they will monitor the effects of solar winds on that magnetic field as part of the European Space AgencyÕs solar-terrestrial science programme. Apart from increasing our understanding of how solar particles interact with the EarthÕs magnetosphere, scientists at ESA hope that the data collected by the Cluster satellites will reveal how solar activity interferes with communications satellites.

According to Ray Merchant of Matra Marconi Space UK, a predominantly French company that has been involved in developing Cluster, the potential benefits for science are very exciting. ÔOnce the satellites have settled into orbit, we should hope to see the first results by October,Õ says Merchant. After its third flight for ESA, Ariane 5 will be handed over to the European consortium, Arianespace, for the launching of commercial satellites.

Sources: ESA, Matra Marconi Space UK Ltd