The perfect landing of the US space shuttle Columbia on July 4 is another important step toward man's mastery and use of outer space.
Here is a quiz to test how much you're up on this subject.
1. What is the name of the spacecraft that will follow Columbia and when will it lift off?
2. Was the first man in space an American or a Russian? Can you name him?
3. What is the Soviet term for an astronaut?
4. Two well-known astronauts are now US senators. Who are they?
5. Not long before the Columbia space shuttle completed its voyage, a Soviet spacecraft also successfully completed its mission. Aboard that spacecraft was a non-Soviet cosmonaut. Who was he and what country does he represent?
6. The American agency responsible for most US spaceflights is NASA. What do those initials stand for?
7. Who said, ''That's one small step for a man, one giant leap for mankind.'' What was he talking about?
8. In September 1979 the American spacecraft Pioneer 11 flew by a very important planet. What was the planet and what did Pioneer 11 report back to Earth about this planet?
9. What is the largest planet in the solar system?
10. How long did it take Pioneer 11 to reach Saturn? Was it six weeks, six months, or six years?
11. True or false: Saturn is about the same size as Earth?
12. As many as five planets - Mercury, Venus, Mars, Jupiter, and Saturn - have been visited by spacecraft. But spacecraft have actually landed on only two of them. Can you name them?
13. The terms Salyut and Soyuz are well-known space terms. What do they refer to?
14. The Soviets made space history when they launched their Sputnik satellite and started the space race between the United States and the Soviet Union. How long ago was that?
15. E.T. is the delightful character in the movie ''E.T.'' But what do the letters E.T. stand for and what does it mean?
1. Challenger. It will be launched in January 1983.
2. A Russian was the first in space. His name was Yuri Gagarin.
4. John H. Glenn Jr., the first American to be put into a space flight that orbited Earth, is a US senator from Ohio. The other astronaut senator is Harrison H. Schmitt from New Mexico.
5. Col. Jean-Loup Chretien. He is from France. He was the first person not an American or from a communist country to go up in space.
6. NASA stands for National Aeronautics and Space Administration.
7. Neil A. Armstrong, commander of Apollo 11, said those famous words when he placed man's first footprints on the surface of the moon. The US moon landing took place at 10:56 p.m. EDT (Eastern daylight time) on July 20, 1969.
8. Saturn. Pioneer 11 sent back pictures showing that Saturn had two more rings and one more moon than scientists had previously believed.
10. Six years. Pioneer 11 rocketed into space in April 1973. It didn't reach Saturn until Sept. 1, 1979.
11. False. Saturn is almost 10 times as big as Earth. But it is much less dense.
12. Spacecraft have landed only on Mars and Venus.
13. Soyuz and Salyut are Russian words. Soyuz means ''union,'' as in Soviet Union. Salyut means ''salute.'' Soyuz is the Russian or Soviet spacecraft. The new version is known as Soyuz-T. Salyut is the Soviet orbital space station or laboratory.
14. The first Sputnik was launched about 25 years ago, in October 1957.
15. E.T. stands for extraterrestrial. Both are Latin words. Extra means beyond or outside. Terrestrial comes from terra, meaning earth. The word territory also comes from the same word.