The satellite sent into space in___is in orbit___above earth.A.the 1990s; 450 kmB.the 1

The Moon and most artificial satellites travel around the Earth in elliptical paths．A.wave

The private satellite industry sprang up in the mid-1960s to relay not only television bro

The satellite might land in the following countries EXCEPT______.A．CanadaB．South AmericaC．

In May 1989, space shuttle "Atlantis" released in outer space the space probe "Megal－lan",

In recent years, a number of communication satellites ______ into orbit about the earth.A．

Without signals from navigation satellites the in