Space is full of mystery. Scientists think that the planets, stars, and other space objects we see make up just 4 percent of the universe Scientists studying space have a lot of choices to make. Future space explorers will have many choices to consider too. Now the choices are yours. Would you rather eat pre-packaged space food or grow your own food in space? Would you rather catch a cold in space or have space sickness? Would you rather travel to Mars or Venus? It's your turn to pick this or that
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