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Tonight was the first science night of 2017B for the Giant Accreting Protoplanet Survey (GAPlanetS). Unfortunately, the timing of the run is such that all of our best targets are reaching their highest point in the sky as the sun sets. This is important because stars rotate the most rapidly with respect to our instrument right around when they reach their highest point, and maximizing rotation is key to our data reduction technique. For that reason, we usually try to center our observations around this “transit” point in order to maximize rotation.

So we started the night by trying really hard to lock on a nearly 12th magnitude star in early twilight. Hernan heroically acquired the star all of about 5min after sunset, but the AO system just couldn’t handle the twilight, so we moved on to a backup target. Unfortunately, seeing was also not as good as we’ve come to expect here at Magellan – hovering near an arcsecond for most of the night. We got a couple of nice long datasets in variable conditions, with occasional setbacks due to the adaptive optics loop breaking because of rapid changes in seeing and high winds.

In better news, my student Clare got her first taste of instrument operation and did a great job running VisAO for most of the night. Here’s a picture of her doing her thing.

Fingers crossed for better weather tomorrow, but the forecast is a bit dire and I used up all of my good weather karma on my eclipse trip to Idaho last week, so I’m not super optimistic. In honor of that amazing event, the song of the day…

 

 

Kate and her student Clare arrived safely today. Their first night is tomorrow night but tonight they helped with trouble-shooting and ran VisAO.

At the end of last night, I was thinking, “Well, that went pretty smoothly, we got on-sky so fast, tonight we’ll finish our engineering early.” Hah.

Today Juan woke Laird up in the afternoon to come help with the ASM cooling pump, which the crew had to replace because when we powered it up yesterday, it was making strange sounds and on its last legs. But getting the new pump working with the proper pressure was not easy, and it took Juan, Laird, and the crew until a couple hours after supper.

Then we went on sky and closed the loop again. But the rotator stuck again as it had yesterday, so we finally decided we had to drag Pato and Felipe out of bed to come trouble-shoot that issue as their work during the day hadn’t yet solved the problem. They were able to fix it… and even said they suspected we would have to call them at night, since they knew that hadn’t been able to reproduce the problem during the day.

Laird, Jared, and Kate spent a couple hours getting the new SDI+ mode to work with the proper offsets and with the rotator to successfully place the star on the VisAO detector.

Meanwhile, about this time I noticed that Clio had warmed up from 54 K to about 67 K. Pretty alarming. So I went out on to the platform to investigate, and noticed the cork was missing. I surmised it had popped off while the instrument was upside down for the rotator tests, about an hour earlier. Oops. So I got out a spare cork (thanks Manny!) and popped it in, and came in and checked the temperature… good, it was dropping! Kate and Clare accompanied me down to the loud scary pump room to make sure the Clio pump itself was ok (since it was pumping on dome air for an hour or so) and it seemed fine.

But then I noticed, an hour or so later, Clio was warming up again. Again I checked on the pump (Clare kept me company again), but it seemed fine still. And everything on the platform looked ok. So I surmised that we must have dumped a lot of nitrogen in the initial instrument flip during the rotator trouble-shooting, so Jared came out with me to fill Clio with LN in the middle of the night. Then I put the vacuum pump back on and monitored the temperatures again… lo and behold now the detector temperature was dropping nicely!

Clare and I were talking about swimming today. Here’s the 2012 US Olympic swimmers, I love this video:

In a new world record, the crew installed the ASM, the Nas, and Clio all in one day. After dinner we finished connecting and cabling everything. We went on sky and closed the loop around midnight. Clio is still getting down to a cool 55 K (-218* C or -360* F). It started out at 287 K (14* C or 57* F) and it was a long cold day for me yesterday:

Laird worked all day today with the crew, with Jared and I joining later so that we could sleep a bit during the day to be up all night. Pato Jones helped Jared and Laird cable the Nas, turn on the guider, and balance the rotator:

We had some trouble shooting to do after getting on sky and closing the loop. This included the Clio motors, nodding, rotating, and at the end of the night the ASM was complaining because it was too cold, so we were trying to let it warm up. We also had problems with X11 windows being too slow on one of the default computers in the Clay control room “Guanaco”, so we switched to a computer of our own:

With the loop closed and before I tried to change any filters, I managed to measure the focus position in one Clio filter, 3.3um:

Well, we’re happy to have gotten on-sky in the fastest time ever, so we will leave it at that and head down to a delicious LCO breakfast:

It’s not thaaaaat cold, just above 0C [32F]. But you have to remember we left months straight of 38C+ [> 100 F] in Tucson. Our blood is thin, you know?

MagAO is ready to bolt on the telescope tomorrow. We spent today unpacking the ASM, moving it up to the summit, cooling Clio, and doing startup checks and cleaning on the NAS. With no new things to install and test, and nothing broken* after the last run, it was an easy day.

There was a big snow storm a few weeks ago. Here are the remnants by the Clay.

I think Vizzy doesn’t remember me.

The real problem is the wind. James Herriot called it a lazy wind — it can’t be bothered to go around you, it just goes through.

*That we remember.

Guess what… we’re back! Laird, Jared, and I made it safely to LCO after 27 hours of travel. Clio is already on the vacuum, pumping down since Tuesday thanks to Jorge Bravo. The sunset was cold and beautiful.

And by the way, Kesha’s back too. Hopefully our 2017B run will be just as powerful and beautiful as this new work of hers:

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Short-and-sweet 2017B Blog Rules:

1. There must be a post every day.
2. There must be a song-of-the-day every day.