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Starts With A Bang!

The Universe is out there, waiting for you to discover it.

: R. Williams (STScI), the Hubble Deep Field Team and NASA/ESA)

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See NASA’s most important image in space telescope history

The Hubble Space Telescope, launched in 1990, was originally seen as a colossal mistake. This one image, taken in 1995, changed everything.

3 min readApr 21, 2025

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35 years ago, NASA launched its : the Hubble Space Telescope.

This photo shows the Hubble Space telescope being deployed, on April 25, 1990, one day after its launch. It was taken by the IMAX Cargo Bay Camera (ICBC) mounted aboard the space shuttle Discovery. It has been operational for 35 years, and has not been serviced since 2009. With a 2.4-meter diameter mirror, it gathers as much light in 1 minute as a 160-mm (6.3″) telescope would require 3 hours and 45 minutes to gather. (: NASA/Smithsonian Institution/Lockheed Corporation)

When it achieved first light, a huge problem appeared: its optics were flawed.

This 1990 image was the “first light” image of the then-brand-new Hubble Space Telescope. Owing to the lack of atmospheric interference along with Hubble’s large aperture, it was able to resolve multiple components to a star system that a ground-based telescope could not resolve. When it comes to resolution, the number of wavelengths of light that fit across your primary mirror’s diameter is the most important factor, but this assumes the mirror is ideally, perfectly shaped, which was not the case for Hubble initially. (: E. Persson (Las Campanas Observatory, Chile)/Observatories of the Carnegie Institution of Washington; Right: NASA, ESA and STScI)

This kept Hubble images from achieving their designed sharpness.

This three-panel image shows the same targeted region with a ground-based telescope that achieves 0.6″ resolution (left), Hubble’s WFPC1, pre-COSTAR image of that same field of view (center), highlighting the spherical aberration problem of the mirror, and the post-servicing mission view of the same star field with Hubble (right), with COSTAR and WFPC2 installed. The difference in resolution and the types of features that can be resolved is breathtaking. (: M.D. Lallo, Optical Engineering, 2012)

To correct this, in December of 1993.

Starts With A Bang!
Starts With A Bang!

Published in Starts With A Bang!

The Universe is out there, waiting for you to discover it.

Ethan Siegel
Ethan Siegel

Written by Ethan Siegel

The Universe is: Expanding, cooling, and dark. It starts with a bang! #Cosmology Science writer, astrophysicist, science communicator & NASA columnist.

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