My favourite subdomain of the NASA website at the moment is JWST for the James Webb Space Telescope. jwst.nasa.gov
I noticed that they have finished cooling down the system and aligning the mirrors, the telescope looks like it is ready for viewing. They will look directly at exoplanets and see what the atmosphere is made of and also look at very old objects in the universe that were covered by dust clouds. It will be very interesting to see what they discover.