Thursday, February 27, 2014

Uh, turns out that we only arrived here yesterday. Even though yesterday was a long time ago.

After some discussion with Zahra, we've deduced that we only arrived in Eureka yesterday. This took some calculation and puzzling. I logged into my blog account today with a guilty sense of “I didn't even write to say we've arrived! I guess if I just do a few days' of posts, I'll catch up soon”. Well. I don't feel so bad now that I realize we've barely been here for 30 hours.

I'll catch you up anyways. Because we did some stuff.

Breakfast was good this morning! I'm pretty sure Roxanne thinks my breakfast standards are low because I was quite happy to find my way to a delicious bowl of porridge. She probably doesn't know just how much I LIKE good porridge. There were eggs and pancakes and other things too, but porridge is delicious. Plus, you can decorate it with colourful fruit.

Sham is studying water vapour, so we were anxious to get the ultraviolet laser put back together today. Chris was going to help us align things in the sky, so we were at the mercy of his schedule in Halifax. Clear skies are also needed. We had both lined up for today, conveniently. We started in first thing. Sham got the pump chamber in with not too much trouble, but the hoses for the cooling system needed some gaskets replaced. That accomplished, we got the UV laser prepped for alignment and measurements.

I was sort of dreading that moment. Putting hardware back together makes me happy. Aligning cranky laser beams can sometimes make me want to cry. Today, however, alignment went very smoothly. Sham had some good ideas for how we could tell how far out of alignment we were starting, and combining that with the usual procedure helped confirm that we were on the right track. I don't think I've ever experienced such a straightforward alignment in my life. Both the UV and Green laser beams were able to be aligned on the optics table in really sensible ways. Chris started the software for alignment in the sky (to get the telescope and the laser beam to look in the same place for each other), and found that BOTH laser beams were within the field of view of the scope already. He didn't have to tweak the alignment much before starting the auto-align program. Even that procedure went well.

The only problem we had all day was one laser turning itself off because I left two cables plugged in that were not necessary (they're for when you only want to fire one shot at a time by pressing a button. I didn't know that the lasers don't like having them plugged in when they're not required), and the laser did not realize that when I put “P-zero-zero” in as a parameter, I really meant “P-zero-one”. It flashed once, and then stopped. Just like I told it to. I gave it some new instructions, and it did those, too. The right ones, this time.

In case you (especially Meike) are interested: I also spent time today staring down a tube at a smallish mirror under a dark inaccessible window at -50 C on a roof in order to watch said mirror rotate by one degree. Maybe less. Slowly. It was thrilling, let me tell you. [Yes, it was useful also. And didn't actually take that long. And I got to go outside during daylight hours.]

Smallish mirror down a dark tunnel. When it moves, it doesn't move much.

We came back to the station once both lasers were firing, and all detection channels were detecting. It's been on the go ever since! Calibrations on the depolarization channel start in earnest tomorrow with us drilling holes through boards.

No comments:

Post a Comment