1993

Hubble Space Telescope

First post-repair image confirms Hubble’s corrected vision

The picture that proved Hubble's eyesight was fixed showed one star, inspected at one in the morning — and NASA kept it quiet for weeks.

AGK+81°266, in focus

At about 1:00 a.m. on 18 December 1993, astronomers at the Space Telescope Science Institute crowded around a monitor to see the first image returned by the newly installed Wide Field and Planetary Camera 2.

It showed the star AGK+81°266 in clear focus, free of the artifacts caused by Hubble's spherical aberration, and the room cheered.

Christopher Burrows held back his own celebration until he had examined the image closely. After that, the repair team knew the optical correction had worked.

Which instrument fixed what

STS-61 had replaced the original camera with WFPC2, which carried corrective optics inside the camera, and installed COSTAR to redirect corrected light to several other instruments. COSTAR did not correct WFPC2.

Once Endeavour released the telescope, controllers began commissioning and testing the repaired observatory; the flawed primary mirror they were compensating for measures 2.4 meters across.

The 18 December frame was the team's direct evidence that WFPC2 was compensating for the mirror error.

Which "first corrected image" the listing means

The listing gives only a year, and the milestone it names is not a single moment. 18 December was the first WFPC2 image the repair team saw; COSTAR's mirrors were deployed on 28 December; the widely reproduced corrected image of the galaxy M100 was taken on 31 December.

So the famous M100 comparison was not the first successful corrected exposure. The initial test target was a star.

NASA kept the result quiet while testing continued and released the first repaired-Hubble image set publicly on 13 January 1994.

Sources

Researched 24 Aug 2026 6 sources not yet audited Date corrected

How this was checked

Researched from the web into a fact sheet and rewritten from that sheet. This article has not yet had an independent model audit. How the pipeline works →

Date corrected. The research places this at 1993-12-18.

What the sources leave uncertain

“First corrected images” can denote several milestones. December 18 was the first WFPC2 image seen by the repair team; COSTAR’s mirrors were deployed on December 28; the widely reproduced corrected M100 image was taken on December 31; and NASA publicly released the first repaired-Hubble image set on January 13, 1994.