Man has always dreamed of traveling away from the Earth and exploring other worlds. The start was made with research balloons, the early rockets and the first artificial satellite. 

They were followed by numerous unmanned probes from the American and Russian sides till finally, in 1961, Gagarin became the first human in space when he orbited the earth. 

Since then, the first man has been to the moon (Apollo 11) and numerous space probes have been deployed to research space and its components. The large telescopes that have been erected at various locations on the earth have also helped. 

In addition to optical telescopes, radio_telescopes have also been deployed; they measure and record the radio_waves of the universe. The space shuttle was developed as a re-usable spaceship. This multi-purpose space glider can put probes and satellites for various purposes into the desired orbit and then return to the earth like an aircraft. 

The Space Shuttle installed the large Hubble telescope above the earth's atmosphere. It sends us impressive images and fascinating data on hitherto unresearched galaxies and phenomena of the universe.