Match the names of human-made satellites with the countries that manufactured them.
sputnik vanguard explorer

Explorer and Vanguard were launched by the United States of America while Sputnik was launched by the Soviet Union. Explorer, which is the first human made satellite made in United State was launched in 1958. The satellite exploded after spending sometime in space. The US scientists went to work and made another satellite which was now named Vanguard. Sputnik was launched by the Soviet Union on October 4, 1957.