Lyman Spitzer Jr was one of the 20th Century’s leading scientists. He was also the ﬁrst person to consider the idea of putting a giant telescope in space and not only lived to see the launch of the Hubble Space Telescope (HST) in 1990, but witness seven years of its incredible contribution to modern science.
Buy why space? Compared to many of the world’s most powerful Earth-bound telescopes the Hubble Space Telescope’s optics are actually quite small. Bar obvious payload limitations, in space the required optics of a telescope are smaller since the ‘seeing’ is always perfect. Looking through Earth’s atmosphere is not unlike trying to watch television through a desert mirage – the seeing is hindered by a constant shimmer produced by the atmosphere. In space the Hubble Space Telescope’s resolution is so great that it’s the equivalent of us being able to distinguish a car’s two separate headlights from 6,000 miles away.
Hubble didn’t have the smoothest of starts however, and for the ﬁrst three years of its life was partially sighted due to an error in the manufacture of its 2.4-metre primary mirror. Thankfully, upon its ﬁrst servicing mission in 1993 its optics were corrected.
It’s most recent scheduled servicing mission took place in May 2009, allowing Hubble to remain operational until about 2018 when it’s successor – the James Webb Space Telescope – is due to launch.
Image credit: NASA/ESA