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 Two washing machine-sized satellites recently went into orbit around the moon. In March, they start together the detailed¹ data about the quakes of the moon’s gravity. The working name of the satellites have been GRAIL A and B，for gravity recovery and interior laboratory. But they just got new names, courtesy of a fourth grader from Bosman Montana. NASA invited US students to submit essay to suggest the names. The Bosman’s entry was picked out of 900 schools representing 11000 students. The winner impressed the judgers with their careful research about the goal of the mission. Because the moon’s gravity gives us tides, the kid suggested the GRAIL A and B’s new handles Ebb² and Flow. The mission is NASA’s first with instruments aboard entirely³ dedicated⁴ to education. Each satellite has a small camera that middle school student can request be aimed that target areas in moon for study. The winning essay writer said that will now called Ebb and Flow are on a journey just as the moon is on a journey around the earth and as the students have begun their own journey of scientific exploration.