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MagAO-X 2024Ab Day 15: Something is better than nothing

Hi! I’m Jensen, a PhD student at MIT and one of this run’s guest observers. This was my first time at Las Campanas Observatory (or any observatory, for that matter), so naturally the universe bestowed upon us the cloudiest, windiest, rainiest, and snowiest May week at LCO in recent memory. The usually featureless “Metro”blue forecasts were often filled with harbingers of astronomical doom. That being said, I’ve loved my time here and hope to come back for future runs!

Today started off strong. The clouds were sparse, the wind was mild, and humidity was low. The local fauna clearly noticed the improvement in conditions, because some grazing guanacos made an appearance for the first time this week.

A juvenile guanaco enjoying the sun. Credit: Gabriele Cugno.

To make the most of the good weather, and to commemorate my last (full) day at LCO this run, I took myself on a self-guided tour of the LCO grounds. It was fun to see the Irénée du Pont and Henrietta Swope Telescopes up close after several days of admiring them from afar.

The Henrietta Swope Telescope.

As frequently happens at LCO, a lovely sunset closed out our daylight hours. A mountain view like this is hard to beat.

My last sunset of the 2024Ab run.

Now, the moment we had all been waiting for: nightfall. The (relatively) clear conditions from earlier in the day had persisted, and after much anticipation, we were finally able to open the dome. The hunt for Hα companions could resume!

She’s alive! Finally some on-sky time with MagAO-X.

Unfortunately, just as the sky giveth, the sky taketh away. After a couple hours of patchy clouds and low- to mid-tier seeing, the clouds returned with a vengeance and forced dome closure. Thus ended our short-lived excursion into actually doing astronomy at a telescope. Some observing is better than none at all, though. At least we generated a few new .fits files in our time at LCO.

On the bright side, things can only get better from here – I look forward to returning and seeing everything to southern sky has to offer!

The Best 15 Minutes

My favourite part of today was when the Clay Telescope’s dome, at long last, opened. I never thought that watching metal panels slide and fold could be so exciting.

The Clay Telescope points skyward after a week of inactivity.

The Song of the Day

Today’s song of the day, for obvious reasons, is Nuages from Nocturnes by Debussy.

xwcl admin addendum

The blog operators would like to include these two photos collected by the rest of the team of our guest observers enjoying a clear sunset:

Gabriele Cugno enjoying the sunset from the hill.
Jensen and Gabriele from the catwalk.

MagAO-X 2024Ab Day 14: What happens to a dream deferred?

Does it dry up like puddles in a dome floor?
Or fester like astronomers on night schedules with nothing to do?
Does it stink like the Atacama desert in the rain?
Or crust and sugar over like flan in the LCO dining room fridge?
Maybe it just sags like Gabriele’s shoulders?
Or does it explode?

The rain has stopped and the clouds are gone but we are still closed. The humidity is still high, apparently high enough to keep the dome from drying. It’s still dripping, so the telescope cover is closed and MagAO-X is covered in plastic. It’s still Gabriele’s night so he’s struggling to hang on to hope.

But we can’t even go on the internal source to do some engineering, because the puddles have everything off.

MagAO-X wrapped up in plastic

Puddles on the Nasmyth
🙁

Laird is still decommissioning MagAO. He was up early enough to catch the remnants of the overnight snowstorm before it all melted an hour later:

Guts of MagAO
She has her own plate!

Jared spent some time tonight dismantling his PhD project, the visible arm of MagAO, VisAO.

“They don’t make em like they used to”
“The last bug in VisAO”

Eden sunset

Vizzy snuggles. Photo Credit: Laird

The best 15 mins of my day were when my friends made a birthday call. The only place I could find to go that wouldn’t disturb anyone and wasn’t icy wind was in the dome, which was all lit up cause of the water.

I know! It’s crazy, because my feet are so large, but i was never into swimming

Jared said VM to me again *cry face*

This spaghetti tastes so much better than glycol

“This isn’t a cheese focused story!
It’s merely cheese adjacent” *sad face*

It flagged every instance of ‘cloud’ as ‘butt’, but I couldn’t let it go to press that way…

The song of the day is for Gabriele:

MAPS May 2024A Night 6: Windy IR WFS CACAO/DO-CRIME

A good final night to an excellent run!

Tonight was our last night this run. I’m really happy with all the progress we made! It was definitely helped by the fact that this is our best-weather run ever, with the highest percentage of useable time: We were open for 5.6/6 nights, or 93% efficiency!

We observed Arcturus with CACAO until transit, took a 4-hour break due to high winds, and then observed Deneb with DO-CRIMES until transit.

We solved many problems this run (don’t worry, we also discovered new ones). Jarron fixed his BLINC issues to get a good pupil on MIRAC and he and Jared even got its display on the AO computer so we successfully fulfilled our dream of using MIRAC as a high-speed PSF viewer for AO. MMTO’s Ben and Tim got us aligned to the optical axis (again) but this time we worked hard to all understand each others’ terminology and tolerances so that when we do it again we do it right. Brian kept us safe by monitoring the wind limits. Grant (in-person), Oli (remotely), Bianca, and Manny got the dichroic and periscope re-aligned so we had good AO pupils. Amali poked the edge actuators until they listened better. Amali, Jared, Olivier, Andrew, and I got CACAO working with both the Vis and IR WFS’s. Bianca, Lauren, and Orlando learned more about the Top Box. Jacob and Suresh got DO-CRIMES working with 20 modes and optimized gains. Manny supervised us all and provided insight about all our hardware issues. Dan and Ruby installed (with the help of MMTO day crew) and connected MAPS and I got to see that side of the operations. And the MMTO staff provided a clean and cozy lifestyle. Thanks to all!

Wind plot at twilight — we were closed from 11pm-3am but got back on-sky and did CRIMES! Our wind limit is sustained above 30mph and/or gusts above 35mph.

On this last night we focused on the IR WFS and trying to understand our hardware problems that we’ll need to fix for next run, as well as to try and get a 20 modes comparison between CACAO and DO-CRIMES. Unfortunately the MIRAC dataset we took with the CACAO loop was pointing into the wind and just when we realized we had to close, and we weren’t able to get a better one. The DO-CRIMES dataset was in better conditions, but they may not be identically comparable. As far as the hardware problems go, we rotated the instrument rotator by 60 degrees and saw that the raggedy edges of the pupil rotated too, therefore (at least in the IR WFS) they are more due to the ASM than to pupil misconjugation. We didn’t have time to switch back to Vis WFS and try the same test, so we should do that next run. The contamination has definitely been a problem and will have to be removed before the next run.

IR WFS pupils before and after rotating the instrument rotator by 60 deg.

The best 15 minutes of today were around 3am after we saw that the wind was steady below our limits and we got to re-open. This was a first for Jacob and very much need as it enabled him to get that last bit of DO-CRIMES testing and data!

The song of the night is “Hold Me Closer” by Elton John & Britney Spears (2023)

MagAO-X 2024Ab Day 13: When the rain starts bouncing, you know it’s bad

This is my seventh trip to Las Campanas Observatory (I think?) and the first time I’ve seen actual, bona-fide precipitation in the Atacama desert. I woke up at 2pm to the gentle patter of rain on my windows, and emerged blinking into daylight. I did try to document it with my phone, but in my sleep-addled state I apparently double-tapped the “record” button and ended up taking some neat videos of the ground.

Fortunately, the early shift was up and could take some pictures.

This would be the spot for a lodge hot tub (Photo by Eden McEwen)
Snow, snow, go away… (Photo by Eden McEwen)
Over to the west we have some low cumulus and to the east we have oh my god run it’s coming (Photo by Logan Pearce)

Vizzy Viscacha was wise to stay under cover as the storm rolled in. Even MagAO-X had to be tucked in safe and dry.

Note that additional measures were taken to ensure MagAO-X aridity. (Photo by Laird Close)

Then, it started really snowing.

Optical depth illustrated (Video by Laird Close)

Laird is the only one brave enough to venture forth from the lodge. He had to get MagAO (not -X) packed up for its international shipment.

Where is the sciatic nerve, anyway? (Photo provided by Laird)

After the snow, we got a snow-bow!

I should request a room change. It’s not fair that the rainbow is only at the La Silla apartments.

Unfortunately, our guest observers Gabriele Cugno from Michigan and Jensen Lawrence from MIT have had just about the worst weather I’ve ever seen here. In fact, this brief break in the clouds after dinner was when Gabriele got his best chance to observe:

Finally, some stars! (Photo by Logan Pearce)

Then the hailstorm started.

(Or maybe it was a graupelstorm?)

Today, by the numbers:

New SSH/VPN questions: 2
Spurious Python environments purged: 11
Night lunches recovered from shutdown: 4
Stars: 14 ish?
Hailstones and/or graupelstones: ≫14
Adaptive secondary mirrors: 1 (slightly used)

Best 15 Minutes of the Day

Probably the rainbow. I swear, natural phenomena here look just the way they are depicted in children’s book illustrations.

Song of the Day

This song of the day is not observer-approved.

“Only Happy When It Rains” by Garbage

Remarks overheard

“So, by the way, how does a pyramid wavefront sensor actually work?”
[rueful laughter in response]

“Whatever. I have no excuses, but I’m also not sorry.”

MAPS May 2024A Night 5: Conjugate planes

Our science cameras image the star in the focal plane, and our wavefront sensors image the star in the pupil plane. A conjugate plane is where your alignment needs to be in order to get those images in focus. After tonight we are wondering whether our VisWFS pupils are conjugate to the telescope pupil.

Summed VisWFS pupils. Why aren’t the edges sharp? Why are the edges raggedy? [Image description: photo of a camera display, black background, white photons in four imperfect images of the telescope pupil, which is round with a hole in the center like a doughnut.]

Tonight we started with Do-Crime on the IR WFS and MIRAC photometry, then moved on to CACAO on the VisWFS when Jared and Olivier called in on Zoom. We first closed the loop on the 50-modes response matrix from yesterday, and it still worked to the extent that it tightened up the PSF!

We next wanted to explore why the higher-order modes had been unstable and why our pupils still looked raggedy and soft on the edges. Because we had trouble calibrating the edge actuators of the ASM in the lab, we have always blamed the edge weirdness on the imperfect ASM calibration. However, tonight we decided to try a Hadamard matrix diagnostic, which pokes each actuator individually (but efficiently) and measures the result on the WFS. The result was that some parts of the mirror were having no effect whatsoever on the wavefront. One of those regions was where the shell is contaminated, but there were other regions too. Even after Amali put some disabled actuators back in the loop, the result was the same.

Olivier started wondering aloud whether our pyramid image was actually conjugate to the telescope pupil. If it’s out of focus of the pupil plane, then the response would no longer be linear, and you would also get mixing of phase and amplitude of the electric field. This could explain why the pupil images don’t look sharp or round.

We did a test where we translated the star about an arcsecond away from the tip of the pyramid, and saw the pupil image shift by around 4 pixels. The shape of the central obscuration changed too.

Left: Four pupil images on the VisWFS evenly illuminated when the star is centered on the tip of the pyramid. Right: After we nod about an arcsecond to put most of the light in the upper right pupil image, the image has shifted a few pixels. If the pyramid was conjugate to the pupil of the telescope, then they shouldn’t have moved.

So we switched to the IR WFS to see if we could see a similar shift. The IR pupils look sharper than the Vis, and they didn’t shift much if at all.

Left: Four pupil images on the IR WFS evenly illuminated when the star is centered on the tip of the pyramid. Right: After we nod about an arcsecond to put most of the light in the upper right pupil image, the image didn’t seem to shift much. So the IR WFS seems to be in better focus to the telescope pupil.

This was about as far as we got with CACAO before it was time to switch back to Do-Crimes. Tomorrow night we will use the IR WFS and compare CACAO and Do-Crimes corrections.

The song of the night is “Gimme more” by Britney Spears (2007)

The best 15 minutes of the day were flying a kite with Amali, Manny, and Bianca. It’s a homemade kite made by Amali, and the gusts across the peak and around the dome are not very laminar, so it was hard to get a sustained flight, but we did get it to dance and dive in the wind. And we also had fun trying but failing to see the green flash again.

Amali flying the kite.
Bianca flying the kite.

That leads us to the bonus song of the night: “Let’s go fly a kite” from Mary Poppins