Works cited

Works Cited
Bellis, Mary. "History of Rockets and Space Travel Innovations." About.com Inventors. About.com, 29 Apr. 2014. Web. 13 May 2014.
"The First Telescopes (Cosmology: Tools)." The First Telescopes (Cosmology: Tools). N.p., n.d. Web. 14 May 2014.
"How Fast Does Light Travel? | The Speed of Light." Space.com. N.p., n.d. Web. 13 May 2014.