Thank you Carla for the wonderful blog post yesterday, and also for taking such good care of us. I of course really mean thanks for delivering our empanadas on Sunday. We’ll see you next turno!
I know it looked like a lot of food, but I was actually somewhat disappointed in our team’s commitment to Empanada Sunday. This tradition at LCO is one of my favorite experiences here, and part of what makes this place so special. I have seen the lounge table tiled with empanadas. A friend of ours even flew home once with her carry-on full of empanadas.
So yes, I ordered 4 empanadas. But that was only because the new night lunch order form limits you to 2 carne and 2 queso. I would have ordered 8. But the trick to hording empanadas here is that you have to defend them.
This is how one does Empanada Sunday on Wednesday.
We said goodbye to Joseph and Warren this morning. Joseph was debugging software while Warren was frantically taking PIAA characterization data until the Sun forced us to close up, and they then ran down the hill to pack and catch the bus. After some sight seeing in La Serena they met up with our fellow Stewardites for the traditional Papas Fritas at the La Serena airport.
Safe travels all.
On-telescope optical characterization can be pretty draining.
Pisco sours are very restorative.
Tuesdays are shift-change day, “turno”, at LCO. So fittingly our departing AOistas passed their relief.
Joseph and Warren got to wave at Logan as she de-planed.
Logan has returned! She managed to stay awake after the 24+ hr journey just long enough to watch the sunset with us.
The first sunset is always special.
Some of our crewmates manage to avoid the stresses of cutting edge astronomical instrumentation research, and just go with the flow.
Contemplative.
Since the day after thanksgiving one of the features of sunset watching from the Clay telescope has been the intense glow of the lodge Christmas Tree.
You can see the blue-white jet coming out of the dining hall.
We’ve recently had cause to learn a new Chilean Spanish idiom: kilometric tacos, which means (more or less) “kilometers of traffic jam”. The strike shows no sign of going away, and the rhetoric has gotten somewhat nasty.
So here are some scenic pictures to take your mind off things.
We had our first Guanaco sighting today:
It seems that the first thing you do after Thanksgiving is put up the tree, even if you didn’t actually celebrate Thanksgiving…
The song of the day is inspired by how we are currently killing time at our secluded mountain getaway.
There seems to be a rule that no matter how early we ship MagAO-X, it won’t get to the Santiago airport until I do. This trip followed that rule. The instrument has now cleared customs and is scheduled to make the journey to LCO tomorrow.
However, it could have been on its way as early as Monday if it weren’t for a nation-wide trucking strike, which started Monday morning. We saw the effects first hand on our drive up from La Serena.
Trucks blocking the right lane of the Pan-Am leaving Santiago. They were blocking the inbound side too.
Trucks were lined up blocking the right lane of the highway, and the highway itself was almost empty. It is usually teeming with trucks going both directions.
Reports are that some concessions have been made and the various unions involved are working on accepting them. The truck is scheduled to leave tomorrow morning. In the mean time, we have been enjoying the comforts of LCO while we get over the 26 hour travel day (and 4 hrs of jet lag). I only look at the calendar once an hour or so to remind myself that we have plenty of days left.
I was already asleep last night, so this is my first LCO sunset of 2022B.
Joseph failed to perform his Day 0 responsibility to set the rules for the song of the day for the run. So, let’s go back to the good ol’ “each post must have a song of the day, and the song of the day must relate to the previous post’s song. You don’t have to explain it (but you can if want to).”
We have waited a long time for a night like last night. MagAO-X had first light way back in Dec 2019. We had just 4 nights to get it aligned to the telescope for the first time, figure out how to acquire a star, and start testing and optimizing our control system. That was just long enough to show that we had a working system, but we left knowing that there were lots of things to improve.
We all know what happened next. For two years we’ve been biding our time in the our lab at UArizona. That both gave us time to perfect a bunch of things, but I think it also caused us to forget a lot of things we learned in 2019. And Extreme-AO is hard. Really hard. It took us most of our 2 week run to start to understand MagAO-X on the telescope facing real turbulence.
Over the last 4 or 5 days I knew that we had really gotten some things working better, and (with lots of remote help from Olivier) had tuned our control system to where it was demonstrating much more stability. But right when we turned that corner the weather also took a turn, and the seeing blew up for 3 nights.
However, Cerro Manqui always seems to save one good show for us AOistas on our last night, and did not make an exception for this run. We had 1/2 arcsecond or better seeing almost the entire night. We even saw 0.35″ on the Baade guider — it is always said such measurements are an upper limit due to the optics involved (but don’t forget outer scale, which is important at LCO, so r_0 is a little smaller). During a period of steady 0.5″ seeing, we performed a thorough optimization of our non-common-path deformable mirror, and took some deep PSF measurements with 1376 modes running at 2 kHz. Here is the result:
The point spread function (PSF — that just means “image of a star” for most purposes) of MagAO-X at 908 nm (in the z’ filter). This is the combo of two images, the central circle used a neutral density (ND) filter to avoid saturation, and is scaled to show the Airy Pattern detail. The rest is without the ND, and shows the faint structures of the PSF. The key feature for AO nerds is the square darker region, our “dark hole”, which is 44 lamda/D on a side (22 in radius). This means we are really correcting the 1367 modes in our basis set.
We’re all ecstatic to finally see such an image from MagAO-X. An amazing team of people has worked incredibly hard for the last 6 years to make this happen. Way to go everybody!
Clay opening for our last night.I took this photo sitting on the dome floor. The sunrise is starting through the lower louvers. At the same time, you can see moonlight reflected off the primary illuminating the bottom of the secondary mirror baffles, and stars are still shining.
We worked with Alycia taking great data all night. As soon as she declared the observing over for the night, we shut it all down and started tearing it apart.
Sunrise disassembly.
After de-cabling and getting ready for the crane, Sebastiaan, Logan, and I went down for a short nap. Laird and Joseph (who went to bed early for this reason) worked with the crew to get MagAO-X craned off the platform.
We wrap MagAO-X in mylar emergency blankets to keep it from overheating in the sun.Mauricio Cabrales steps back to make sure MagAO-X is going up straight on the crane.MagAO-X is now in the cleanroom, waiting to go back in its boxes for the trip home.
We have one more big day of crane ops tomorrow to get our stuff all packed up to ship home. I confess that as soon as I finished processing the PSF image, Sebastiaan and I started listing all the things we know aren’t perfect yet, and started making predictions for how much better we can make the next one (faster, more modes, predictive control laws, better NCP optimization . . . we can go on). So we’ll be busy over the next 6 months.
The song of the day is one my favorites. For obvious reasons I think.
Metallica covering Astronomy. Unless this is your first time with us, you’ve heard it before.
MagAO-X is proving to be a complicated beast. Just when we think we’re making progress at taming it, we find another thing that doesn’t quite work yet — or is just plain failing.
Sometimes we need help from our collaborators working on similar AO systems. We’ve been getting really nice performance, but with a touch of instability that has made it difficult to keep that performance for long periods of time. We use the CACAO software developed by Olivier Guyon for the SCExAO system. Olivier has been working with us all along to make MagAO-X go fast, and today I got up early to dive into the details to figure out what has been causing these subtle stability issues.
To test things out, Olivier was running experiments on SCExAO in Hawaii while I was doing the same on MagAO-X. It looks like we succeeded! We are much happier with the new calibrations we took this afternoon.
MagAO-X (blueish grey) and SCExAO (orange and purple) working together. Olivier can be seen thinking hard.
The bigger assist came from our friends on the MAPS project. We’ve been suffering from a failing rotator on our atmospheric dispersion corrector (ADC). This little motorized device rotates a prism to keep the Earth’s atmosphere from going all rainbow on us.
Knowing that MAPS is using the same rotator — and importantly are not currently looking up at stars — we sent up the ole’ bat signal to see if they could get one to us. Oli Durney (who is the optical engineer for MagAO-X!) sprang into action and tore apart MAPS’ ADC and got the stage to FedEx. From there it went to Jeb Bailey in Santa Barbara, who just happened to be coming to LCO 48 hours later. (Jeb is himself part of the MagAO-X team, though that’s not why he came this time).
So we got the replacement stage delivered last night, and today did the replacement.
The ADCs are a little hard to get to when we’re installed on Clay.Laird and Jared cutting zip-ties to remove the cable.Laird calmly considering the problem.There is just no good way to get to this part of MagAO-X at the telescope, but we managed.
Once we got the instrument buttoned back up and our new calibration applied, we went back to work doing coronagraphy at H-alpha looking for planets.
Joseph driving MagAO-X in SDI coronagraphic mode. Laird and Sebastiaan providing helpful suggestions.
Here’s a video of some parts of MagAO-X working. Woofer, tweeter, WFS at top left. At bottom and from left are the H-alpha channel, continuum channel, and then our LOWFS camera which is capturing light rejected by the coronagraph.
A short period of MagAO-X observations.
Logan figured out how to get Vizcachas to be our substitute Easter Bunnies. they’re going great.
Joseph got a special meal. He claims to not know why. I was jealous.Two culpeos watched us eat supper. The traditional sunset pic.
