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| It begins in the United States at 2 a.m. on Sunday, March 8. |
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| Mars lost ocean of water to space |
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| Four billion years ago, a primitive ocean on Mars held more water than Earth's Arctic Ocean. But 87 percent of Mars' ocean was lost to space. |
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| Use Big Dipper to find Little Dipper |
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| Big Dipper ascends in the northeast on March evenings. Little Dipper is always in the north, because North Star is the last star in its handle. |
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