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The cancellation of the 16-day flight means that the crew and scientists on the ground are pursuing only their most important experiments in the few remaining hours left before the shuttle laboratory is closed. The US space agency NASA decided Sunday to bring the orbiter home 12 days early because of fears of weakened power generator could explode. The generator has been turned off, leaving the shuttle with only two thirds of its normal power supply. To conserve electricity for the experiments the crew is working in dimmer lighting than normal and has turned off all unessential equipment. NASA says the two remaining generators are sufficient for Tuesday’s landing, but had nevertheless ordered the astronauts to study emergency procedures in case another fails. The shuttle team has expressed its disappointment at the curtailment of the science mission, and says enough data have already been collected in the materials, combustion and biological experiments to push science further ahead. The scientist’ goal is to complete the experiments on a later shuttle flight. David Batlery, VOA news, Washington.