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21st CENTURY EXPLORER
Are we there yet?
Why do astronauts eat tortillas instead of bread?
How would your body change in space?
How can we travel faster in space?
What will replace the Space Shuttle?
Why do robots travel places before people?
Why return to the Moon before going to Mars?
Why do we want to study and travel to Mars?
Where would a space explorer find water and oxygen?
What would you find on the Moon’s surface?
What would you hear in a weather report from Mars?
How will your imagination help you become an explorer?
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WHY DO ASTRONAUTS EAT TORTILLAS INSTEAD OF BREAD?
Glossary

freeze-dried – a process that preserves (food, for example) by rapidly freezing and drying in a vacuum

intermediate moisture- a substance with most moisture removed before packaging; allows water to be added later to return it to its original state

irradiated - to treat by exposure to radiation

rehydrated - to restore fluid to something dehydrated

semi-liquid – a material (food, for example) which may look and feel like a liquid but is resistant to movement

thermostabilized - stable when heated

empty
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Why do astronauts eat tortillas instead of bread? Newsbreak
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NATIONAL EDUCATION RESOURCES
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NATIONAL EDUCATION STANDARDS
National Science Education Standards (NSES)

The following National Education Standards are addressed in this educational package.

Science (NSTA/NRC)
Health (AAHPERD)
Technology (AAHPERD)

For an alignment see the Educator Section.