LISA Pathfinder launch grounded to analyze Vega upper stage

Launch managers in French Guiana have delayed liftoff of a European gravitational probe pathfinder at least one day to study the thermal extremes the upper stage of its Vega rocket booster will encounter on the flight, officials said Tuesday. The launch of the European Space Agency’s LISA Pathfinder was set for overnight Tuesday (early Wednesday, French Guiana time), but engineers elevated concerns about the readiness of the Vega rocket’s liquid-fueled fourth stage, which must ignite two times to deploy the 1,906-kilogram (4,202-pound) spacecraft into the correct orbit. More

(Source: SpaceFlight Now - Dec 2)