Thirty years ago, on April 24, 1990, Hubble was carried aloft from NASA’s Kennedy Space Center in Florida aboard the space shuttle Discovery, along with a five-astronaut crew.

Deployed into Earth orbit a day later, the telescope opened a new eye onto the cosmos that has been transformative for our civilization.

Hubble is revolutionizing modern astronomy, not only for scientists, but also by taking the public on a wondrous journey of exploration and discovery. Hubble’s never-ending, breathtaking celestial snapshots provide a visual shorthand for Hubble’s top scientific achievements. Unlike any space telescope before it, Hubble made astronomy relevant, engaging and accessible for people of all ages. The space telescope’s iconic imagery has redefined our view of the universe and our place in time and space.

“Hubble has given us stunning insights about the universe, from nearby planets to the farthest galaxies we have seen so far,” said Thomas Zurbuchen, associate administrator for science at NASA Headquarters in Washington, D.C. “It was revolutionary to launch such a large telescope 30 years ago, and this astronomy powerhouse is still delivering revolutionary science today. Its spectacular images have captured the imagination for decades, and will continue to inspire humanity for years to come.”

Unencumbered by Earth’s blurring atmosphere, the space observatory unveils the universe in unprecedented crystal-clear sharpness across a broad range of wavelengths, from ultraviolet to near-infrared light.

Hubble’s top accomplishments include measuring the expansion and acceleration rate of the universe; finding that black holes are common among galaxies; characterizing the atmospheres of planets around other stars; monitoring weather changes on planets across our solar system; and looking back in time across 97 percent of the universe to chronicle the birth and evolution of stars and galaxies.

Hubble has yielded to date 1.4 million observations and provided data that astronomers around the world have used to write more than 17,000 peer-reviewed scientific publications, making it the most prolific space observatory in history. Its archival data alone will fuel future astronomy research for generations to come.

Hubble’s longevity can be attributed to five space shuttle servicing missions, from 1993 to 2009, in which astronauts upgraded the telescope with advanced instruments, new electronics and on-orbit repairs. The venerable observatory, with its suite of cameras and other instruments, is expected to stay operational through the 2020s, in synergy with the upcoming James Webb Space Telescope.

 

First Hubble images were blurry, fuzzy

The Hubble Space Telescope was deployed from Space Shuttle Discover on April 25, 1990.

After initial on-orbit activation and checkout of the telescope’s systems, it was time for the much-anticipated “first light” images.

The initial images, however, puzzled scientists, as they showed stars not as single well-focused points of light, but as blurred and fuzzy. Investigators learned that the telescope’s primary mirror suffered from a production error, its edges too flat by 0.003 mm, resulting in an optical problem called spherical aberration. While this significantly degraded the capability of several of Hubble’s instruments to return the exceptionally detailed photographs, the telescope still produced some good images.

NASA put in place a plan to fix the Hubble’s optical problems without resorting to actually repairing the mirror, which was an impossible task. Since the magnitude of the spherical aberration was well-defined, engineers designed a set of mirrors that astronauts could place aboard Hubble during the previously planned first servicing mission.

The task of fixing Hubble’s degraded optics and also replacing its solar arrays that caused unexpected vibrations fell to the crew of STS-61, the first Hubble Servicing Mission in December 1993.

The crew consisted of Commander Richard O. Covey, Pilot Kenneth D. Bowersox, and Mission Specialists Kathryn C. Thornton, Claude Nicollier, Jeffrey A. Hoffman, F. Story Musgrave and Thomas D. Akers.

Two days after launch, Nicollier grappled Hubble and secured it in the payload bay of Space Shuttle Endeavour. During the next five days, the EVA teams of Hoffman/Musgrave and Thornton/Akers alternated in conducting an unprecedented five spacewalks to accomplish the repairs. They installed the Corrective Optics Space Telescope Axial Replacement (COSTAR) in place of the HSP, sacrificing the one instrument to enable the telescope to achieve its full potential. They replaced the original WF/PC with an upgraded WF/PC-2 and replaced the original solar arrays with a new pair with stiffer properties to eliminate the unwanted vibrations.

Within a month, new images from Hubble indicated the repairs returned the telescope to its expected capabilities, providing astronomers with a unique observation platform.

The Hubble Space Telescope is a project of international cooperation between NASA and ESA (the European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute in Baltimore conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy in Washington, D.C.

For more on the Hubble Space Telescope, please visit https://www.nasa.gov/content/hubbles-30th-anniversary and https://hubblesite.org/