This past week I spent a few days in Leiden for a meeting of MIRI’s European Consortium, of which I’m a memebr, and a number of our closest US collaborators from NASA, the Space Telescope Science Institute and the University of Arizona. Over the summer, we completed our final test campaign for the instrument at the Rutherford Appleton Lab in Didcot.
For 86 days a fully assembled MIRI was held at its chilly operating temperature, 7 Kelvin, inside the cryo-chamber at RAL. During this time, every single wheel and pixel of the instrument got a workout, and with our test equipment, specifically designed to emulate scientific operations on board the James Webb Space Telescope (JWST), we got to see the first science-like images from all parts of the instrument, the imager, coronagraph and the spectrographs. Apparently this is the longest a space instrument has ever been tested continuously at cryo temperatures in Europe, prior to delivery.
Some other fun stats: 51 people worked for around 6000 person-hours (I did a measly 80 of those); we produced 6.5 terabytes of data, consisting of 8562 exposures, 2,775,036 detector frames. Those 51 people now have on average 168 exposures to work through – and that’s a conservative estimate, as not all 51 people are involved in the in-depth test analysis.