Over the past 28 years Hubble has photographed innumerable galaxies throughout the universe, near and far. But one especially photogenic galaxy located 55 million light-years away holds a special place in Hubble history. As NASA made plans to correct Hubble's blurry vision in 1993 (due to a manufacturing flaw in its primary mirror) they selected several astronomical objects that Hubble should be aimed at to demonstrate the planned optical fix. The magnificent grand spiral galaxy M100 seemed an ideal target that would just fit inside Hubble's field of view. This required that a comparison photo be taken while Hubble was still bleary-eyed. The Wide Field and Planetary Camera 1 was selected for the task. The picture had to be taken before astronauts swapped out the camera with the vision-corrected Wide Field and Planetary Camera 2, in December 1993. Following the servicing mission Hubble photographed the galaxy again, and it snapped into crystal clear focus. The public celebrated with Hubble's triumphant return to the clear vision that had been promised. Jaw-dropping pictures of the vast universe that followed have not disappointed space enthusiasts. Because of the astronaut servicing missions, Hubble's capabilities have only gotten better. To commemorate the 25th anniversary of the first servicing mission, this two-panel photo compares the blurry, pre-servicing 1993 image (left) to a 2009 image (right) taken with Hubble's newer, Wide Field Camera 3 instrument, installed during the last astronaut servicing mission to the space telescope.
Top Image Credits: NASA, ESA and Judy Schmidt
These three images are of the central region of the magnificent spiral galaxy M100, taken with three generations of cameras that were sequentially swapped out aboard the telescope, and document the consistently improving capability of the observatory. The image on the left was taken with the Wide Field and Planetary Camera 1 in 1993. The photo is blurry due to a flaw (called spherical aberration) in Hubble's primary mirror. Celestial images could not be brought into a single focus. The middle image was taken in late 1993 with Wide Field and Planetary Camera 2 that was installed during the December 2 – 13 space shuttle servicing mission (SM1, STS-61). The camera contained corrective optics to compensate for the mirror flaw, and so the galaxy snapped into sharp focus when photographed. The image on the right was taken with a newer instrument, Wide Field Camera 3, that was installed on Hubble during the space shuttle servicing mission 4 in May 2009.
Credits: NASA, ESA, STScI and Judy Schmidt
Last Updated: Dec. 4, 2018
Editor: Karl Hille
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