(Image: SSPL/Getty)

THE Hubble Space Telescope has for the past 25 years powered NASA’s dream of putting people into space. Launched on 24 April 1990, it was designed to be looked after by flesh-and-blood astronauts, and repairs and maintenance have run up a bill that would have paid for several new telescopes. But what would have been the point of that?

Hubble has been the training ground for a generation of spacefarers. Servicing it has taught NASA everything it knows about building and maintaining the International Space Station. It is also a very fine instrument indeed. Its work is celebrated in Taschen’s new book Expanding Universe, which intersperses pictures taken by Hubble, like the one of the variable star V838 Monocerotis below, with images of Hubble’s planning and construction. This includes the photo of the 2.4-metre primary mirror shown on the left, which is so smooth that if you were to scale it up to the size of the Atlantic Ocean, its waves would be less than 10 centimetres high.

(Image: NASA, ESA and H. E. Bond (STSCI))


Statistics like this have inspired film-maker Chris Riley to celebrate the telescope in Hubble’s Cosmic Journey, a film for the National Geographic Channel that was first screened on 18 April. He has managed a major coup. Optical engineer Bud Rigby and his colleagues at Perkin-Elmer, who made the mirror, shouldered the blame for an optical flaw that took three years to correct. Twenty-five years on, vilified by the press and their own colleagues, the men at first refused to participate. Luckily, Riley’s persistence paid off, and their extraordinary technical achievement is finally being recognised.

See more: Happy birthday Hubble: A quarter of a century of inspiring images

This article appeared in print under the headline “Hubble’s ocean of glass”

When this article was first published, it misnamed V838 Monocerotis.