Congratulations Dr. Logan Pearce!

It’s been quite a week for our intrepid veteran-turned-teacher-turned-professional-astrophysicist. The hardest part of the dissertation defense is usually scheduling it at a time all your committee members can attend, and this time was no different. In true Texan style, Logan lassoed her committee and roped them in to a defense in-person and online this June 11th, 2024.

Unfortunately, I was only able to watch the public portion of the defense from afar via Zoom. I also vicariously enjoyed Logan’s big day through the subsequent vignettes dropped context-free in our Slack’s #blog-ops channel.

(I think of these as a sort of wishful thinking. Posters wish a blog post into existence by posting things that might illustrate it. Well, who am I to deny them?)

Logan began with a title slide crammed full of the stuff she’s been working on these past five years:

That’s me in the picture! I’m in the “18” by “Participants” on Zoom! (Photo by Eden McEwen)

She gave an overview of MagAO-X, for which she published the first ever peer-reviewed science paper using the instrument:

Twinkly star goes in, scienceable star comes out. Any questions? (Photo by Eden McEwen)

Gave the people what they crave (i.e. astronomical discoveries):

We got one, folks! (Actually, eight.) (Photo by Eden McEwen)

And let us know where we can find her in the near future:

At the Michigellan Telescopes, of course (Photo by Eden McEwen)

Because we’ve never been sticklers about anything*, the party to celebrate Logan’s defense took place before the successful conclusion of the defense. Frankly, I’m gutted to have missed it. Fortunately, former-pastry-chef-future-Dr. Jay Kueny made Logan’s favorite pineapple buns in my stead. (No doubt with Melanie’s help!)

*Except label maker use, circus activities, and other important lab rules.

I’m told a pastry chef can make a pretty darn good pineapple bun (on the first try, too!)

Meanwhile, back in linear time, Logan was locked in a room(/Zoom) with four dangerous scientists and had to escape with only her wits. The labmates / COVID bubble-mates group chat—now scattered between California, New Mexico, Tucson, and New York—waited anxiously for word that Logan had surmounted her final academic trial.

Did she beat school?

Dear readers, of course she did.

The group chat accordingly recognized the ascension:

A full program of celebrations was called for, beginning with further chef magic from Jay.

By “chef magic” I am of course referring to how Jay just happened to have non-alcoholic Grand Marnier on-hand. (Photo by Eden McEwen)

The Cardboard Crowning of newly-minted Ph.D.s is a tradition as old as the academy itself. (Don’t quote me on that.) So, naturally, Logan was not about to get away without a hat pointing out what giant nerd just got all doctorfied.

From now on, you have to wear that getup to do astronomy. It’s the rules. (Photo by Eden McEwen)

Some more glamour shots of the extremely regal crown Eden made:

Celebrations for Logan continued that evening with beers at the site of her triumphs, with a special guest appearance by the Director of Steward Observatory and head of the Department of Astronomy at University of Arizona: Dr. Buell Jannuzzi.

Logan’s miniature MagAO-X crafting project (Photo by Eden McEwen)

What’s that he’s looking at? Well, there might be a blog post about that soon. Sure looks like there’s a dang viscacha in that instrument.

Song of the Day

Today’s song of the day is brought to you by the temperature delta between June in Tucson (high: 109ºF) and Michigan (high: 84ºF).

“Too Darn Hot” by Ella Fitzgerald (really, the definitive version, don’t you think?)

Bonus Hedgehog

I modeled this hedgehog in a Ph.D. tam for Logan with the intent of getting it 3D printed. Turns out 3D metal printing is, like, expensive. But it was too good to keep to myself.

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.

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.”

MagAO-X 2024Ab Day 7: Chilly in Chile

Greetings from the downstairs lounge, where you can see exactly as many stars as upstairs. That’s right: it’s another cloudy evening here at Las Campanas Observatory, but one ray of bright starshine has broken through: Dr. Alycia Weinberger! She had to spend a night in Miami, and another night in Santiago, but she has finally arrived!

We all forgot to document her arrival for the blog, so have a condor instead.

Since the clouds stubbornly remained at sunset, we went on an expedition beneath the Magellans.

Okay, that’s enough natural beauty. (Photo: Alycia Weinberger)

There was a fad in the 90s for two-for-one telescope deals, along with vague plans for interferometers (some realized). True to form, the two Magellans are connected by a tunnel.

This is where I’d put my interferometer… if I had one.

We also explored the maze of twisty passages.

Reminiscent of her majesty’s navy?

We descended into the oubliette.

If someone messes up the instrument alignment, they will be confined below.

There are removable floor grates to confound your enemies.

Legend has it that a secret sub-sub-basement exists, hiding untold riches.

Here’s a view upwards through the central core where all the wires and hoses snake up to the telescope platform, eventually entering a cable wrap.

Don’t look up.

There is a two meter thermal exhaust port:

Ask not about the biblical mouse plague.

Evidence of researcher enthusiasm underneath 100 tons of telescope.

Evidence of Dr. Weinberger’s arrival, upper left in gray.

Maggie Kautz bid a fond farewell to MagAO-X, as she will be leaving in the morning. Maggie has graduated, which means she probably needs to defend her dissertation soon.

anTop? What’s an anTop?

Then she came back and replaced a picomotor that had gone on strike due to the cold conditions.

It could be Professor Laird Close under that getup, for all we know. (Photo: Jared Males)

Once she finishes up her doctorate, she will be starting a new job… as a staff engineer at Steward Observatory, home of MagAO-X! (And some other stuff I guess.)

After we bid our actual farewell to Maggie-O-X, it was time for Josh to drive. We found that all of Sebastiaan’s notebooks were still on the old ICC data drives, so some surgery was required to get them back into place on the new and improved SSD array.

Okay, keep an eye out: we’re looking for a 500GB folder called “SYH_notebooks”

As I write, there’s some serious disk pic analysis happening in the lounge, so maybe this night won’t be a complete bust…

Highlight of the Day

Per 2024Ab rules, the best part of the day… might be the underground Magellan tour, actually! So, you already read all about it.

Song of the Day

“Black Moon” by Screaming Females

(Technically a waxing gibbous, but I can’t see shit.)

Our semi-occasional recurring feature: “Overheard at LCO”

“We’re just roadies for a metal band called MagAO-X.”

“At least on the internal source I can’t break anything.”
Why would you say that?!

“It’s a dissertation. It doesn’t have to be perfect.”

MagAO-X 2024Aa Day 11: Wanderer above the sea of fog

Wanderer Above the Sea of Fog (Viscacha Edition)” by Caspar David Friedrich and an AI

The day-to-day operation of an experimental extreme adaptive optics instrument, pushing all the boundaries at once, can feel like lurching from crisis to crisis. We need to get better airflow in the bowels of our electronics rack. We need to automate the fifty-three step alignment process. We need to debug this segmentation fault in our control software. We desperately need to do laundry, but we’re unwilling to sacrifice sleep or work time.

Today, a portentous wind blew all through dinner. Jialin and Laird got on right at sunset, and it looked for a minute like we’d have an okay night. predicted calm conditions. In fact, it’s continuing to predict calm conditions.


Yes, the wind line is going into the humidity plot.

We have to close the telescope for average wind speeds of 35 mph, and it’s gusting to 52 mph. Jialin is no longer allowed outside without a tether in case she blows away.

We tried to open the door to the outdoors but nature said “no. ❤️”

The conditions at Las Campanas will blow you away.

At times like these, the hard-working AOistas thank Mother Nature for delivering exceptionally bad conditions so that we can focus on what’s important: software development, esprit de corps, and blog #content.

We did take some data before we got shut down, though. And, who knows, maybe this will all just blow over. Meanwhile, Jared was not satisfied with the amount of wind and went to get some extra fans for our instrument. Armed with a couple of graduate students, he went to hunt in the storage building between telescopes.

Inside a box cryptically labeled VisAO (possibly some viscacha-themed instrument?) were some fans for cannibalization. This will hopefully help us even out temperatures in the electronics rack.

“Hello old friend”— Jared

2024-04-24 00:00 CLST

Sparkles “Eden” McEwen turned 25 today! We only use UTC for consistency in our instrument, but birthdays are celebrated in local time.

We’re happy you were born!

2024-04-24 01:27 CLST

Wind’s dying down! Finally!

Jared took some data down at the lodge while he was checking on his laundry. Seems like he got a bit of sky rotation.

If you visit the southern hemisphere you can see the Magellanic Telescopes, discovered by astronomers in 2001.

Tomorrow’s a half-night for me, so I’m taking advantage of my last full night to file my second and final blog post for 2024Aa. Until next time, enjoy some hair-metal revival from STARBENDERS.

Song of the Day

We can face the darkness, baby. It’s all in the way you play the game.



I know we’re not the first ones to use AI image generation, but its ability to capture South American animals has greatly improved since I last tried it out.

O B E Y (prompted by Sebastiaan)
The tail-less giant mountain viscacha has not been seen since the last ice age.
The ELBT (Extremely Large Banana Telescope) (prompted by Jay)

MagAO-X 2024Aa Day 7: Anti-Lunch Lunch Club

Hard to believe I’m back here! I was so convinced 2023A would be my last trip to Chile with the MagAO-X team that I tried to do all my tourist stuff in one go last year. In the past year, I’ve defended my dissertation, moved across the country, and begun a fellowship at the Center for Computational Astrophysics of the Flatiron Institute, a division of the Simons Foundation. (That is officially how we are supposed to refer to it, officially. Unofficially, it’s just “CCA.”)

Today’s lesson is that sometimes you try your best to sleep all day and just can’t manage it, even if you exhausted yourself working the longest day. Those of us with this problem were today’s accidental day crew: myself, Sebastiaan, Maggie, and Eden. We got up for lunch and did some daytime engineering on MagAO-X.

An HDFS introduced in the first act must go on-sky by the fifth.

Maggie and Sebastiaan prepared to test the Holographic Dispersed Fringe Sensor (patent pending?) on-sky, shoring up its credibility for inclusion in the Giant Magellan Telescope project’s plans. I helped Eden get started with fixr, my Python library to read the format for our images that have been extremely reordered. I did some work on packaging fixr as well as getting various guest observer software creature comforts working consistently once again.

We all met up at dinner (save Jialin, who had to attend a class online). Tuesday is turno day, where the crew that’s been working since last Tuesday gets replaced by all new staff fresh from their week off-duty. While I will miss Sr. Verdugo’s desserts, this turno‘s cooks are breaking new ground in LCO salad bar operations. Imagine, sliced strawberries in a salad! I’ve never seen the like here before.

Josh Liberman regaled us with tales of the risks of excess cheese and the good sense of always traveling with Strunk & White’s elements of style. Katie always carries nail clippers instead. (I’m not sure why either of those were needed at dinner, but it’s certainly preferable to be well-spoken and well-groomed than the opposite.)


Meanwhile, down at El Pino, Logan Pearce was enjoying the local wildlife and natural environment.

The viscachas look different in La Serena
Wait for the green flash

Today also saw the arrival of Jialin Li, who arrived on the mountain after a one-day delay not unlike my own. (Did you know LATAM has a ninety minute cutoff for accepting checked bags? Well, I do now.)

Jialin is not only Laird Close’s graduate student but is also a heuristic interactive algorithm for observer time scheduling. Each astronomer has certain targets, which rise and set at certain times, and a certain number of nights (or fractional nights) allocated by their institution. Balancing these constraints is hard, possibly even NP-hard. Unfortunately, Jialin was incommunicado in transit yesterday, and the schedule was pulled in all directions in her absence. Sebastiaan began compiling constraints based on when people would be ready for various engineering tasks, when they’d be arriving onsite, when they’d be leaving, and whatnot.

So, when she arrived, the schedule was still very much in flux. The control room at dusk was alive with furious multitasking. At one point Logan Pearce called in from the hotel in La Serena (where she is recuperating) to try and understand the scheduling spreadsheet, which was live updating rapidly before her very eyes. After much hemming and hawing and proverbial horse-trading, an acceptable schedule solution was reached—just as the sun set.

Figure 1: Ph.D. advisor elated that his student (center) survived her travel odyssey

For tonight’s scheduled performance, the role of Dr. Alycia Weinberger was played by the understudy, Jay Kueny. Jay acquired more data of some of Alycia’s favorite debris disk targets. MagAO-X can image shorter wavelengths than MagAO+Clio could, and produces better images than MagAO+VisAO did. This means the residual light from the star doesn’t spread out as far, making it easier to detect and characterize the parts of the disk closest to the star in our images.

The bad seeing conditions we had initially mellowed out to more typical 0.5–0.6” seeing after the sun had been down for a little while, and we got some good data on HD 61005 for Alycia. Alas, it could not last. Clouds began to gather on the horizon, and the wind picked up something fierce. The telescope can’t operate in high winds, so this kiboshed a lot of our plans for the evening.

You can see what happened on the plot below, most easily recognized by the big chunk of missing seeing data. Winds got above 35 mph average, which meant we had to shut down. Since there’s never any shortage of things to do, and MagAO-X has an internal “telescope simulator” source, we attempted to make the most of this time for engineering.


While Jared continued polishing MagAO-X Halpha performance with internal calibrations, a few of us retired to the break room to audition songs for Song of the Day. There were a few rejected choices (too sad, too raunchy, contains swears, etc.) but I think I picked a good one.

Around 4:58, Sebastiaan popped his head outside and reported seeing “a ton of stars” so we all traipsed back upstairs bright-eyed and bushy-tailed… only to hear Jared say “don’t get excited.” Although a ton of stars were visible, the humidity was climbing fast, and threatening clouds were gathering in the North.

We all got less excited. As we got close to sunrise, humidity plateaued and the average wind speed stayed low long enough that our telescope operator (the incomparable Alberto Pastén) decided it was safe to reopen. At this point, science was off the menu: not only was engineering scheduled for the end of the night, but the conditions were too bad for any but the brightest targets anyhow.

The Chekhov’s HDFS introduced in the beginning of the blog post must go off by the end, so Sebastiaan quickly slotted it in to take some data under realistic 90th-percentile conditions. It was tough to keep things stable, and the dispersed fringes occasionally disappeared entirely, but we took some data of a double star and got to see all the fringes doubled. That’ll be fun to disentangle.

it’s like a dandelion!

After we finished, Sebastiaan and I stayed up for breakfast and were rewarded with this view of the valley filled with clouds trapped in the inversion.

Today’s song of the day expresses a desire for a counterfactual reality in which the clouds are absent and the seeing is always below half an arcsecond. I think that’s what they were singing about, anyway.

Song of the Day

“Say it Ain’t So” — Weezer