Read the passage from "The Race to Space: Countdown to Liftoff" by Erik Slader and Ben Thompson. Sputnik was a small metallic sphere only two feet wide and weighing just 184 pounds. It was launched by a Soviet R-7 rocket into a low Earth orbit, flying at an incomprehensible 18,000 miles per hour and an altitude of 560 miles. It was so fast that it circled the planet once very hour and 35 minutes! The reason this passage was included in the body of the article is because it provides *


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