A Decade of Discovery HubbleSite
Telescope & Science
Investigating Space Photos
The Hubble Story Video

Hubble's Orbit The Vault

Hubble orbits the Earth at an altitude of about 353 miles (569 kilometers). It takes about 97 minutes to complete one orbit around the Earth. Hubble passes into the shadow of the Earth for 28 to 36 minutes in each orbit. The orbit inclines at a 28.5-degree angle.

This orbit is high enough that Hubble is above the Earth's atmosphere and can conduct its science operations without the negative effects of the atmosphere.

Seeing through Earth's atmosphere is similar to looking at objects through a pool of water. Remember how little you can see when you open your eyes under water and how much better you can see when you are out of the water. It is very similar as far as science is concerned with the telescope. The Earth's atmosphere acts similarly to water and greatly reduces what we can see in space from the ground. Hubble is in orbit above the atmosphere because it has unrestricted visibility into space and can "see" much better than anyone or anything on the ground.