MAPS 2023A Day 4: What’s a couple of shmims between friends?

After the previous night’s untimely clouds, we were fortunate to have clear skies and moderate-to-good seeing all night. The MIRAC-5 team continued work on their instrument, which the adaptive optics operator Eden found extremely useful for its fast video feed showing how (and if) our adaptive optics experiments were improving their images.

I, however, mostly spent the night shmim-wrangling.

MAPS (like its cousins MagAO-X and SCExAO), uses shared memory images—shmims—to relay data at high speed from a wavefront sensor, through an adaptive optics loop, to the point where commands are handed off to the adaptive secondary mirror.

There it is! Way high up off the ground!

Of course, a shared memory image is just a hunk of memory with a hint about the type of data it contains (floating-point numbers, integers of various sizes, etc.). One could just as easily use a shmim to store a vector, or a single number, or a data cube.

One such vector was my target yesterday: the vector of “modal gains.” Each entry in the vector scales the system’s correction for that mode by the factor you provide, allowing you to correct low-order modes more strongly while easing off the high-order modes that you may not be able to control as effectively. It’s sort of like the EQ sliders on a stereo.

What’s he listening to?

Still, one may ask, what is a “mode” in an AO system? The answer: something too abstruse, dear reader, to bother this blog with.

That won’t stop me, though! You know how the optometrist fiddles around with their equipment to find the best focus for your eyes, and only then starts in with the next level: correcting for astigmatism? Well, AO systems fiddle around many times per second to get the best focus for the telescope, and the best astigmatism correction, and a few more besides. It turns out there are “levels” beyond astigmatism, accounting for even more subtle changes to the image. We need to correct those for the sharpest image possible.

That’s the short version, anyway. The long one involves math. If you’re looking for a low-stress beach read this summer, I can recommend Adaptive Optics for Astronomical Telescopes by Hardy (1998).

In MagAO-X we divide the gain controls into blocks of modes and use buttons to bump them up or down to improve our correction. MAPS does not use all the same MagAO-X software, and the two of us from the MagAO-X team were missing the fun of clicking a lot of buttons really fast. So, while Andrew develops the real, production-grade, network-enabled button-pushing infrastructure for MAPS, I brought a little bit of MagAO-X from home.

This tool replicates the UI we have for MagAO-X gain tuning, with the additional trick of a parametric gain curve. Rather than tuning the modes by blocks, one can type in some parameters to define that pink curve with a different gain value for every single mode. Clicking “Apply” then fires the numbers off into the appropriate shmim, where they are applied to the AO loop.

Of course, all the software in the world can’t change the laws of physics. Summer seems to have finally made it to Mt. Hopkins, and with it the need for active ASM cooling has become acute. It turns out that bending glass mirrors takes a lot of power, and some of that power escapes as heat. That heat, in turn, makes the whole system (red-faced and panting) call for a time-out while it collects itself.

It’s not often I wish a mountaintop were colder and windier. Tomorrow’s our last night, and we’ll have to see if we can keep our cool when it’s a balmy 54ºF at 1 A.M.

Song of the Day

“Que Sera” by Wax Tailor. It’s a groove, trust me.

MAPS 2023A Day 0: Stranger in a familiar land

MAPS is The MMT Adaptive optics exoPlanet characterization System, an upgraded adaptive secondary AO system for MMT. For the next week or so, it is installed on the telescope and the team has important engineering and science to do. To this effort, the XWCL has contributed one CACAO expert on the ground (Eden McEwen) and two remotely (Jared Males & Olivier Guyon). We tried to contribute two on the ground, but the departure of Avalon from Tucson means there was a vacancy in the dorms.

I’ve always wanted to see the MMT, ever since the daily high in Tucson cracked 95ºF (if not longer!). I expressed this wish to Manny, and someone vouched for me as “useful”, and thus did I secure Avalon’s spot for myself.

Now, on the MagAO-X team, our fearless leader likes to surprise and alarm us by turning up in unexpected places—to the point where we have a calendar tracking his movements so we know what timezone he’s operating under. Most recently, we learned he was in Tokyo thanks to Hello Kitty.


I thought it was time to return the favor, by heading up Mount Hopkins without a peep to Jared. We had it all worked out: Eden was going to write blog posts with me lurking in the background of her pictures, and we were going to wait and see if Jared noticed… but the cat’s out of the bag already.

And Eden’s asleep.

So I’m writing the blog post.

MMT, formerly the Multiple Mirror Telescope (currently the Mmt Mmt Telescope), is a 6.5-meter telescope in Southern Arizona at the Fred Lawrence Whipple Observatory. It’s part of Steward Observatory, and University of Arizona. Also the Smithsonian. Also Harvard. Everyone wants a piece of the F.L.W.O., and who can blame them? It’s gorgeous country out here.

UofSAO? Photo: Eden McEwen
That’s the MMT! Photo: Eden McEwen

The night shift left Tucson around 1 P.M. with all the food for their 1–6 days of meals in tow (depending on length of stay). With a mere hour-and-a-half drive separating their lab in Tucson from their telescope, the MAPS team has MagAO-X thoroughly beat for convenience.

The delicate optical bits were all in place well before sunset, thanks to efforts of the day team, allowing me to take this glamour shot when we opened up the dome.

Look at that little guy!

The telescope operator had kindly tipped the whole contraption over to make a compelling group photo:

Who would win: Fifteen people, or one wiggly mirror?

The night began with breezy but clear conditions and seeing hovering just under 1″. Naturally, the first bit of the night was spent debugging, aligning, and turning things off-and-on-again. (We know all about that.)

Once starlight was hitting the wavefront sensor (thanks to Oli) and the pupils were looking good and round (thanks to Robin and Jacob of UToronto): it was time for some CACAO: Compute And Control for Adaptive Optics. The same ultra-fast, ultra-flexible AO system that powers SCExAO and MagAO-X is being implemented as the new brains controlling the adaptive secondary.

Andrew and Eden worked diligently through many fiddly bits of computer plumbing to get pixels from the sensor and commands to the adaptive secondary (under the watchful eye of Jess):

Eden hard at work, with a cameo by Vizzctor V. Viscacha.

Meanwhile, in Tokyo, MAPS East was supporting the effort over Zoom:

They put those eight monitors up so they don’t have to see a bare ugly wall.

Their combined efforts got us to our final checklist item of the night: close the loop. With an hour or so to go until sunrise, the globally distributed team worked on improving the calibration and setting things up so tomorrow night we can skip right to “the interesting part.”

Stay tuned.

Song of the Day

In honor of the MAPS East team’s contributions, I submit this Japanese groove that’s been stuck in my head.

chilldspot – “mitei”

MagAO-X 2023A Bonus Feature: Santiago de Chile

I didn’t get into academic astronomy to travel, but I didn’t get into academic astronomy to avoid travel, you know what I mean?

I’m bringing the good ship Ph.D. into port in the very near future, and I have been to Chile some six times (should have been more, but thanks covid) without having seen more than observatories and airports (again, thanks covid).

After a month away from home I was exhausted and had a to-do list as long as my arm, but I decided if I didn’t take some personal travel now I never would. In the spirit of MagAO-X 2022B Day 3: An astronomer’s guide to Valparaíso, Chile, I present 2.5 days in Santiago de Chile.

I gratefully acknowledge the advice and suggestions of Dr. Matías Díaz (lately of drone-piloting fame) and the MagAO-X Chilean Cultural Attaché Dr. Susana Henriquez.

Day 0:

On Sunday the 19th, we left the observatory. A van transported us and the luggage of a one-month stay (multiplied by four people) from Las Campanas down to La Serena airport.

We obtained Kunstmann Torobayo (times four) and papas fritas, as is tradition.

Sebastiaan, Jared, Jeb of the XKIDS, Eden, and myself at La Ultima Llamada (La Serena Airport bar)

After a short hop to Santiago airport, I parted ways from the rest of the MagAO-X team.

Continue reading “MagAO-X 2023A Bonus Feature: Santiago de Chile”

MagAO-X 2023A Day 22: Above and beyond

This evening Dr. Matías Díaz, a support astronomer here at Las Campanas Observatory, helped us take a next-level team photo.

Thanks for taking the video with your drone, Matías!

Of course, we have more people in our group than pictured, and by the time we visit again in 2024A (!) we’ll probably have even more new members. By then I will have decamped for the Flatiron Center for Computational Astrophysics in New York, but it’s famously hard to see stars there. Maybe they’ll invite me back.

It’s our last night on sky, which is always bittersweet. Tomorrow’s a long day of removing from the telescope. So, what have we got to show for the past 22 days?

  • 14 terabytes of high-contrast astronomical data (and counting)
  • a new observing mode that keeps light where it should be, allowing us to pass these savings on to the consumer (shout-out to Ms. Lowfs)
  • a handle on our induced DM ✨sparkles✨, which will let us unravel the profound mysteries of pyramids (thanks Eden McSparkles)
  • a lot of improvements to VIS-X (gaan met de banaan, Dr. Haffert)
  • one new extreme-AO-fed instrument (shout-out to Noah & the Ex-Kids, opening for Weezer on tour this summer)

We’re about to commission our knife-edge coronagraph, but this blog post can’t wait. It’s time for the prospective students to choose their Ph.D. institutions, and we must put our best foot (feet?) forward.

Song of the Day

“Anemone” by Brian Jonestown Massacre

I went to a liberal arts college, which makes some people assume I didn’t study physics or something. In fact, astronomy is one of the quadrivium of artes liberales, and my college had a Department of Mathematics and Astronomy before it had a physics one. It’s physics now, though. So there.

Still, a smaller student body and more flexibility in courses of study meant some interesting cross-pollination between departments. One of my classmates in Advanced Intro Astronomy was named Maurissa, and she was actually a music major. She took astronomy with us, but she also had a band, did stuff with electronics, and was in a Balinese gamelan ensemble. Anyway, she was the one who introduced me to Brian Jonestown Massacre, the above psych-rock band with good vibes.

Bonus Song of the Evening

Sometimes you don’t need something musically interesting, and swoopy synths suffice. Anyway, the blog title reminded me, and after all—we are almost home.

“Almost Home” by Above & Beyond and Justine Suissa

MagAO-X 2023A Day 18: Lookin’ sharp

MagAO-X threw a bit of a tantrum today, but Jared got it calmed down before sunset. Ever since Eden gave it a swift zapatazo, the operator workstation has been moody and fractious. Compounding our difficulties, one of the rack computers was on the fritz at the same time.

Jared says that in the world of Navy nuclear power, you don’t conduct drills for two simultaneous faults. That means what happened today is simply not allowed in the Navy, which should reassure us all. (I have informed our instrument computers that we will be adopting this same policy going forward.)

Tonight Alycia Weinberger, the forever young Las Campanas Frequent Flyer, is obtaining more disk imagery. Conditions have been passable, though I hear past midnight things started getting good. Stay tuned.

Sparkles vs. speckles cage match tonight on pay-per-view

At this point even the newest graduate students have become adept at driving the AO system. Still, they mustn’t get complacent, because we continue to add more complexity in order that more things may go right.

Hi Jialin!

For example, I am hiding in the rec room trying to refactor Lookyloo, the “quicklook” script that has grown additional responsibilities. Not coincidentally, I’m going through my headache meds faster than the chocolate-covered espresso beans. (Does anyone know what Excedrin is sold as in Chile?)

The goal is to bundle up the relevant image archives and system telemetry files that encompass an ‘observation’ and stuff them into a single unit for uploading to the CyVerse Data Store back in North America. CyVerse operates scientific computing infrastructure in connection with the University of Arizona, meaning we have a hotline to their head honcho for our data hoarding. The idea here is that our highly compressed data formats will use the limited bandwidth between continents more efficiently, allowing us to “rehydrate” the observations into more conventional formats upon demand.

Fortunately, CyVerse has no relation to Facebook’s Metaverse, and we will not be issuing NFTs of our observations. (For archive-browsing readers of the future: NFTs were a bubble/pump-and-dump scam of the early 2020s, with JPEGs taking the role of tulips.)

In further news from the software side, we ran our first all-Python MagAO-X device last night! My PurePyINDI2 library successfully allowed us to command Sebastiaan’s VIS-X camera from the same interfaces we use for scripting and interacting with the rest of MagAO-X.

Of course, that doesn’t look like anything, so here is a picture of a guanaco:

Photo credit: Alycia Weinberger

Technically, it was our second PurePyINDI2 device, as Maggie-o-X had already been taunting the observers through Jared’s add-on speaker for the operator workstation. Its repertoire includes:

  • “Beep boop bop” when activating Low Order Wavefront Sensing, with or without Ms. Lowfs in attendance.
  • Gaan met die banaan” when taking exposures with VIS-X, our most Dutch camera.
  • “P.I. is asleep. I am the P.I. now.” (among other choices) when nothing alert-worthy happens for 15 minutes.

It alerts on more useful criteria, as well, like changing targets and AO loop events. But those messages are strictly business.

Being out of the critical path for operations tonight means I have taken the chance to do some (lower-tech) astrophotography. It turns out that the image processing on an iPhone can wring detail out of moonless nights, as long as you have a tripod and some patience.

The camera app captures some more diffuse detail than my eye does, but I can see way more stars.

I have speculated that “computational photography” boffins will eventually forward-model the whole sky and paint the stars in after the fact. Recently, it was revealed that Samsung has taken this conspiracy theory as a product suggestion for their latest phones.

Once our image processing is allowed to make up details that aren’t there, I predict we’re going to find loads of planets.

Song of the Day

There were never any ‘good old days’. They are today, they are tomorrow! It’s a stupid thing we say, cursing tomorrow with sorrow.

“Ultimate” by Gogol Bordello

The world’s foremost Gypsy Punks were also my first ever show as a wee teenager in Atlanta, Georgia. I didn’t know much about live music, but a Ukrainian dude capering around the stage and emptying a bottle of red wine on the pit seemed pretty punk rock to me.

Lead singer Eugene Hütz also had a starring role as Alex in the movie adaptation of Everything is Illuminated. They even worked the band in in this one scene:

“My name is Jonathan”