The Hubble Story

Servicing Missions

Shortly after Hubble was deployed in 1990, the observatory's primary mirror was discovered to have an aberration that affected the clarity of the telescope's early images. Astronauts repaired Hubble in December 1993. Including that trip, there have been five astronaut servicing missions to Hubble.

› SM1: Dec. 2-13, 1993
› SM2: Feb. 11-21, 1997
› SM3A: Dec.19-27, 1999
› SM3B: March 1-12, 2002
› SM4: May 11-24, 2009

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This photograph of NASA's Hubble Space Telescope was taken on the second servicing mission to the observatory in 1997. Credit: NASA
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From the dawn of humankind to a mere 400 years ago, all that we knew about our universe came through observations with the naked eye. Then Galileo turned his telescope toward the heavens in 1610. The world was in for an awakening.

Saturn, we learned, had rings. Jupiter had moons. That nebulous patch across the center of the sky called the Milky Way was not a cloud but a collection of countless stars. Within but a few years, our notion of the natural world would be forever changed. A scientific and societal revolution quickly ensued.

In the centuries that followed, telescopes grew in size and complexity and, of course, power. They were placed far from city lights and as far above the haze of the atmosphere as possible. Edwin Hubble, for whom the Hubble Telescope is named, used the largest telescope of his day in the 1920s at the Mt. Wilson Observatory near Pasadena, Calif., to discover galaxies beyond our own.

Hubble, the observatory, is the first major optical telescope to be placed in space, the ultimate mountaintop. Above the distortion of the atmosphere, far far above rain clouds and light pollution, Hubble has an unobstructed view of the universe. Scientists have used Hubble to observe the most distant stars and galaxies as well as the planets in our solar system.

Hubble's launch and deployment in April 1990 marked the most significant advance in astronomy since Galileo's telescope. Our view of the universe and our place within it has never been the same.

Hubble Facts

•       Hubble does not travel to stars, planets or galaxies. It takes pictures of them as it whirls around Earth at 17,500 mph.

•       NASA's Hubble Space Telescope has made more the 1 million observations since its mission began in 1990.

•       NASA's Hubble Space Telescope has observed 38,000 celestial targets.

•       Hubble has circled Earth and gone more than 3 billion miles along a circular low earth orbit of 350 miles altitude.

•       As of Hubble's 24th anniversary in April 2014, Hubble observations have produced more than 100  terabytes of data.

•       Since January 2013 the Hubble generates 844 gigabytes per month.

•       About 4,000 astronomers from all over the world have used the telescope to probe the universe.

•       Astronomers using Hubble data have published more than 11,000 scientific papers, making it one of the most productive scientific instruments ever built.

•       Hubble weighs 24,500 pounds -- as much as two full-grown elephants.

•       Hubble's primary mirror is 2.4 meters (7 feet, 10.5 inches) across.

•       Hubble is 13.3 meters (43.5 feet) long -- the length of a large school bus.

History of Hubble

The Hubble Story

A detailed look at the Hubble Space Telescope from idea to conception to blast off into space. Learn all about the project from its infancy to the maturing telescope it was when launched in 1990.

Historical Milestones of the Hubble Project

Explore the development of the Hubble Space Telescope and learn about the important dates in history that has contributed to the success of the telescope.

Hubble Accomplishments

image of the galaxy NGC 4603

Age of the Universe

Thanks in part to the Hubble Space Telescope, we know the universe is 13.7 billion years old.

DL Tau image

At Galaxies' Cores

Nearly all galaxies may harbor supermassive black holes.

image of supernova seen by HST

How Planets Form

The Hubble Space Telescope has helped scientists determine the process of how planets are born.

artist concept of HD 189733b

Extrasolar Organic Matter

The Hubble Space Telescope detected the first organic molecule discovered on a planet outside our solar system.

DL Tau image

Dark Energy 

The Hubble Space Telescope detected a distant supernova that suggests the universe only recently began speeding up.

Combination of two Hubble WFC3/UVIS images of the pluto system from June 28 and July 3, 2011 showing known moons and their orbits and new moon P4.

Plutonian Moons

Hubble found four moons around dwarf planet Pluto.


Page Last Updated: April 25th, 2014
Page Editor: Rob Garner