Much of what we know about the universe is thanks to pictures taken by the Hubble Space Telescope which was launched by Nasa in 1990 Plans to build a telescope that could be launched into deep space began in the late 1970s, soon after the first space mission. Twelve years and US$2 billion later, Nasa launched the Hubble Space Telescope. It was to dramatically alter our perceptions of what we know about the universe and our place in it. The Hubble didn't get off to an easy start. Almost as soon as it was launched, there were problems with the big mirror. It took two years to repair, but it was worth the wait. With the telescope properly set, the Hubble began sending back incredible images. It gave us the first awe-inspiring pictures of cosmic creations such as black holes. The image of the Eagle nebula - a massive cloud of gas and dust in which stars are formed - is one of the most memorable pictures captured so far. It shows bright points of light within three huge towering columns of gas, each one larger than our own solar system. Another image that created a massive stir is known as Deep Field. The telescope focused on a seemingly blank patch of sky for hundreds of hours, hoping to get a glimpse of the edge of the universe. The image shows thousands of young galaxies - it is a photo of the very beginning of the universe. The Hubble's digital cameras take pictures as greyscale pixels. This means that they are downloaded as black and white images, but the ones that we can see on the Nasa site ( http://grin.hq.nasa.gov/ ) are usually brightly coloured. The colours are added to show the dispersion of chemicals and highlight special features. The Hubble Telescope whirls around the Earth incredibly fast - at five miles per second - and takes just 97 minutes to orbit our planet. In case you were wondering how the telescope got its name, it was named after the astronomer Edwin Hubble. He was the first person to look through a telescope and realise that the universe isn't static; it's expanding. This is known as Hubble's Law.
