The Cosmic Web Imager is a new instrument, built at Caltech, that is coming later this summer for use on the 200-inch Hale Telescope. It will detect and map faint ultraviolet emissions from the intergalactic medium and give astronomers lots of data for testing the standard model of structure formation in the universe.
The instrument isn't quite all together, but a few days ago part of the CWI team came to Palomar to make sure that the finished instrument will be able to be properly installed on the telescope.
Here are two photos from Wednesday's test fit.
All went well and the real instrument should install nicely when it arrives.