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The James Webb Space Telescope (JWST) was originally supposed to be launched around 2007, but it is now delayed until at least 2021. Some of this is due to simple building mistakes like loose bolts, but mostly it’s because the JWST involves lots of new ideas and technology that is far more advanced than the old Hubble Space Telescope. Inventing and testing these new technologies and ideas has taken longer than people first expected, but this isn’t surprising because advanced projects like this are often late as they are intended to push science forward by tackling the unknown and solving difficult problems.
The James Webb Space Telescope is shown here being tested to ensure it survives the temperature extremes in space