Apparently in a decade or so, we should have telescopes good enough that they will be able to measure the expansion of the universe by watching the changing red-shift of distant galaxies. This might even happen in my lifetime! 

https://www.forbes.com/sites/startswithabang/2019/11/12/this-is-how-astronomers-will-finally-measure-the-universes-expansion-directly/

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Even with today's most powerful telescopes, we can only measure redshifts to a resolution of about 100-to-200 cm/s, which means we'd have to wait centuries to even begin to measure changes in how we view these distant objects.

The ELT(*) should be sensitive to changes in redshift that correspond to additional shifts of just 10 cm/s in overall magnitude.

This represents an improvement of a factor of 10-to-20 over existing telescopes, and means that if we wait just a decade (or perhaps a decade-and-a-half) once the ELT comes online at full power, we should be able to measure the expansion of the Universe directly.

(*) Extremely Large Telescope - zero points for imagination

It's exciting, but I think the previous OWL would have been much better. Just imagine the images from a 100 meter mirror!

Still, I can't wait for it to be built, the images should be amazing.