Happy Birthday Hubble
Today the Hubble Space Telescope celebrates its cake day, having spent 22 years collecting some of the most iconic images in science. Though possibly the most successful unmanned space program to date, its manufacture was beset by a decade of technical setbacks.
When it was finally launched in 1990, within a few weeks it became apparent that there was a major problem with its optical system. Images it returned were ten times more blurry than what they were supposed to be. The problem was identified to be a misshapen primary mirror.
Though it was one of the finest mirrors ever cut, boasting smoothness almost to the atomic scale, it was found to be ever so slightly too flat - by about 2µm at the edges. This lead to the catastrophic aberrations present in the images it brought back.
It was too costly at the time to bring it back to Earth for a refit and too impractical to conduct a refit in space. Instead, engineers came up with an ingenious solution - to fit it with extra optics which would act as a monocle, correcting the aberration. This ‘hack’ was done by astronauts of STS-61 Endeavour and worked like a charm.
Data collected by Hubble since then has had a tremendous impact on astronomy, astrophysics and cosmology.
However, I think that its served an even higher purpose. Before Hubble, we had but a glimpse of the beauty of outer space. However, in the 22 years of its operation it has given us a whole encyclopaedia of the richness and diversity of galaxies, nebulae, stars, supernovae etc.
Images like the Pillars of Creation have become culturally iconic and significant. When I was little, I was enthralled by these images, and I’m sure Hubble is partially responsible for some of my early interest in science. In fact, I’m absolutely sure this can also be said of many other students of my generation who grew up with Hubble.
On behalf of these people I say: Hubble, we salute you!
