Hubble Space Telescope

Hubble Space Telescope as seen from the Space Shuttle Discovery on mission STS-82.

The Hubble Telescope was an American space probe that explored distant space beginning in 1990.

It included one of the biggest engineering mistakes ever when its telescopic lens was mistakenly placed backwards on top of other lens, thereby reducing the clarity of the images. In a space mission, astronauts were able to add a corrective lens to it which restored it to its intended performance.

The telescope is named after astronomer Edwin Hubble whose observations of galaxies led him to the discovery that the universe is expanding.