The first US space shuttle blasted into orbit on ____ . Space shuttles were the first reusable spacecraft. The United ____ space shuttles were used to carry payloads up to other spacecraft. Space shuttles did some great things. They transported satellites ____ deployed spacecraft. Shuttles could stay suspended in space for as long as ____ weeks, ____ allowed scientists to carry out experiments. Experts hoped that ____ space vehicles would lower the hight cost of space flight. ____ it was very expensive to keep the shuttles running, so NASA terminated the space shuttle program in 2011

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