Launched April 24, 1990

The Hubble Space Telescope (HST) was named for Edwin P. Hubble, the first astronomer to prove the existence of galaxies beyond Earth’s galaxy, the Milky Way. Launched from the United States space shuttle Discovery in 1990, the HST is the most powerful telescope in the world. The spacecraft is orbiting 380 miles above Earth and is scheduled to remain in space for 15 years. Although it has been plagued by problems since it was put into orbit, the HST has nevertheless provided scientists with valuable information about the stars and the universe.

Telescopes have been used by astronomers since the seventeenth century. The Dutch inventer Hans Lippershey reportedly built the first telescope in 1608; the Italian scientist Galileo made the first astronomical studies with the instrument in 1610 when he discovered the craters on Earth’s moon as well as the moons of Jupiter...