Last night, the camera was finally warm enough inside to take it off the optics cryostat, so we did that and started taking apart the camera so we can do our work on it. We’ll do all the modifications over the next 2-3 days, then close it up and start cooling it all down again so we can test whether the upgrades worked. (If they cause problems, we’ll have to open it up again to fix them… hope for no problems!)
Here’s a picture of me (what we call a “hero shot”) with both cryostats after we separated them. The big white one contains some of our optics, and the red one in front is the camera.
You might ask “Why are you wearing a hat and warm overalls inside?” Good question. The overalls are heavily insulated, very warm. I’m also wearing my fleece jacket. With all the electronics and compressors that operate our instrument turned off, the room underneath the telescope is pretty cool – about 50F or so. So it’s kind of like working in a warm refrigerator. After a long day working, I tend to get cold more easily, and it’s nice to be in something that keeps you warm at that point.
In this next picture, I’m actually working. Abby and I are removing the various layers that cover up the focal plane of the instrument, so it can get very very cold (down to 1/3 of a degree Kelvin, right near absolute zero). We’re wearing those white gloves so we don’t get any finger-grease on the parts inside the cryostat.
Finally, here’s what is inside. This is the backside of the focal plane, so you can’t see the detectors. What you do see is all the wiring and the thermal connections to various stages of refrigeration; the coolers are off to the side, out of the picture inside the cryostat.
By the time we got to this point, it was about 11pm, so we stopped and headed in for the midnight meal (“midrats”). Tomorrow we take the focal plane out and get to work!