An Ariane 5 rocket carrying the European Space Agency’s Envisat satellite, Europe’s largest and most expensive satellite was rolled out to the launch pad yesterday. If all goes well, the rocket will launch Friday morning at 0107 GMT (8:07 EST Thursday night) from Kourou, the European spaceport in French Guiana and carry the 8,000 kg satellite into orbit. Envisat will spend the next 5 years monitoring the health of the Earth’s oceans, ice caps, land and environment.