The Telescope
Hubble: the eye we put above the sky, and what it showed us.
The eyeWhat Hubble is
The Hubble Space Telescope was carried into orbit by the Space Shuttle Discovery in April 1990. Above the air that blurs every view from the ground, its 2.4-metre mirror sees the universe sharp and clear.
At first its mirror had a tiny flaw and its pictures were blurred. In 1993 astronauts fixed it in orbit. Five servicing missions, the last in 2009, kept it alive, and it still works today.
What it sawThree discoveries that changed us
- The Deep Fields. In 1995 Hubble stared for days at a tiny, empty-looking patch of sky. It found thousands of galaxies, each with billions of stars.
- The age of the universe. Hubble helped measure how fast the universe expands, a key step to knowing its age: about 13.8 billion years.
- The acceleration. Its observations of exploding stars helped show that the expansion of the universe is speeding up, driven by something we call dark energy and still do not understand.
Look for yourselfWhere the sky is open to everyone
All of Hubble's data is public. Its images and measurements are kept in an open archive, and anyone can see what the telescope is looking at right now. Astronomers also keep a shared catalogue of millions of stars and galaxies, free to search. The links below take you there.
Go deeperSources
Everything on this page was written for you here. These are the places we drew from, if you want to walk further on your own: