Hubblesite.org

Exactly 25 years ago today, the Discovery space shuttle took off with the Hubble Space Telescope aboard.  For all the mind-blowing images Hubble has been able to bring to us, the project started actually pretty badly…

Above all the funding challenges that such a large project faced, there were many issues on how and who should grind the primary mirror.  In all three mirrors were built by three different companies should there be issues during production.  The Challenger disaster in 1986 delayed the launch of the telescope, and when it was finally placed in orbit, a faulty mirror wasn’t able to correctly focus the image to the clear and crisp views everyone had expected.  As the flaw was due to an error in the calibrating instrument during the final shaping of the mirror, it meant it was flawed to perfection, and could therefore be corrected by giving it “glasses”.  It wasn’t until 1993 that corrective optics were incorporated and we could finally start exploring the potential of the telescope.

As the Hubble Space Telescope is in low earth orbit it is within easy reach to be serviced by astronauts, and five shuttle missions were dedicated to servicing Hubble, the last one being in 2009 to extend the operation until 2020.  By then the James Webb Space Telescope (JWST) should be operational.  Something to note here is that while Hubble could be serviced and maintained over time due to its proximity to Earth, JWST will be too far out, located at the L2 Lagrange point – 1.5 million km, beyond Moon’s orbit.

To celebrate these 25 years, NASA and ESA have released this wonderful galactic firework: Westerlund 2

Source: Hubblesite.org