Curiosity about space is as old as humanity. We gaze at the sky, amazed by its complexity and depth. We are captivated by the astonishing views that even the smallest of telescopes can provide and are held spellbound by the spectacular wonders recorded by the world's largest and most complex telescopes. We struggle to comprehend the full extent of outer space, unable to conceive that there may well be over 20,000,000,000,000 (twenty trillion) stars in the universe.
Space is an incredible world of stars, planets and galaxies, where time is measured in billions and billions of years and where distance is gauged in millions and billions of light years, each an inconceivable six trillion miles in length. Such numbers are almost unreal. At times this world seems imaginary, an exceptional piece of fantasy with a heavy dose of science fiction.
Photo. The Cartwheel Galaxy was transformed by a collision with another galaxy. Later, we will learn why this remarkable galaxy looks the way it does. Courtesy NASA, K. Bourne/Space Telescope Science Institute.
Perhaps what intrigues us most about this remarkable realm is explaining how the universe came about and what else is out there. We seek to discover, to witness and to wonder. In the end, we hope that all of our knowledge will help in precisely pinpointing the age of the universe. So elusive has an exact age been that its finding might well be the greatest breakthrough in cosmology since the Big Bang theory.
In the study of astronomy, we stand on the shoulders of giants of the past. Copernicus, Galileo, Kepler, and Newton sparked our interest in the study of light energy from space and made way for the astronomers of today. They inspired an American astronomer named Edwin Hubble.