1.   Ace could see it only because it was moving, blotting out more stars as it and the shuttle flew towards each other.

2.   Although the shuttle can fly with only one guidance unit working, mission rules require all three to be performing flawlessly at liftoff.

3.   But the shuttles have flown little of late.

4.   For example, once in orbit the shuttle flies backward, engines first.

5.   I walked outside, and at that exact moment the shuttle flew over, an orange tail of fire trailing behind a bright point of light.

6.   In some cases, shuttles have flown with less than a dozen passengers.

7.   NASA disagreed with that total, saying the shuttle would fly even if the international station were canceled.

8.   The shuttle can fly quickly to retrieve a free-flying astronaut during a spacewalk.

9.   Typically, the shuttle flies with its payload bay pointed toward Earth.

10.   U.S. shuttles flew a series of nine docking missions to Mir over three years, culminating in what was to be the final mission last June.