1.   Armchair astronauts also need to experience the claustrophobic conditions faced during actual space travel.

2.   Astronauts also need less iron and, because sodium increases bone loss and results in urine too salty for the plants, they must consume less salt.

3.   But Culbertson said that Soyuz can be run automatically in case astronauts need to use it to return to Earth.

4.   Even younger astronauts need a few weeks to get used to gravity again.

5.   NASA officials said the astronauts might need to walk in space to inspect the damage.

6.   The astronauts will need time to train for the spacewalk for that operation.

7.   Time for a third spacewalk was built into the mission schedule in case astronauts need it to complete the intricate work.

8.   Time for a third spacewalk was built into the mission schedule in case astronauts need more time to complete the intricate work.

9.   The theory is that astronauts will need to produce much of their own food to colonize the moon, or during the extended voyages needed to travel to Mars.

10.   National Aeronautics and Space Administration officials said his last flight is not a matter of his age, rather other astronauts just need a chance to develop their skills.