The Orion Nebula, made up of 3,000 baby stars - all are younger than one million years old.

In order to observe the Sun, Moon and stars more closely from Earth, powerful telescopes are required that look into the depths of space from space observatories.

As far back as 1946, the astronomer Lyman Spitzer had suggested using a telescope in space, but technology, optical equipment and space travel were not sufficiently developed to allow this scientific step forward.

Only since 24 April 1990, has there been an observatory in space that is in orbit around the Earth: commissioned by the American and European space authorities, NASA and ESA.

The observatory was the first in a family of four space telescopes in the NASA Great Observatory Program, followed by the Compton Gamma Ray Observatory in 1991 and the Chandra X-ray Observatory in 1999.

August 2003 saw the launch of the fourth and last telescope in the NASA program - the Space Infrared Telescope Facility (SIRTF).

In contrast to Earth telescopes, these space telescopes can look into the furthest depths of space without any disturbance from the Earth's atmosphere. They can see everything that the human eye cannot see. For example, the Orion Nebula, made up of 3,000 baby stars, which are younger than one million years (nothing by space standards).