Weeks after its April 1990 launch aboard the Space Shuttle Discovery, NASA released the Hubble Space Telescope's first light images, showing a star cluster with clarity surpassing ground-based observatories despite an as-yet-undiscovered flaw in its primary mirror. The telescope would go on to transform astronomy after a 1993 servicing mission corrected its optics, eventually producing some of the most iconic images in the history of science. Hubble remains operational today, over three decades later.
On May 20, 1990, NASA released the first images captured by the newly launched Hubble Space Telescope, offering the public its earliest glimpse of what the billion-dollar observatory could do. The images, showing a double star and a star cluster, were sharper than anything achievable from ground-based telescopes distorted by Earth's atmosphere—yet astronomers soon realized something was subtly wrong. The images weren't as crisp as engineers had promised.
Within weeks, NASA confirmed a mortifying flaw: Hubble's 2.4-meter primary mirror had been ground to the wrong shape, off by just 2.2 microns—a fraction of the width of a human hair—but enough to blur its vision significantly. The error became a public embarrassment and late-night comedy punchline, threatening to undermine confidence in NASA's flagship science mission.
The story turned triumphant in December 1993, when spacewalking astronauts aboard Space Shuttle Endeavour installed corrective optics, essentially fitting the telescope with glasses. The repaired Hubble went on to deliver the Hubble Deep Field, stunning images of the Eagle Nebula's 'Pillars of Creation,' and observations that helped determine the age and accelerating expansion of the universe—becoming perhaps the most scientifically productive instrument ever built, its early stumble almost forgotten against three decades of discovery.