For about a year, Laird, Alex H., and I have been putting together the protoype-High Contrast Adaptive Optics Testbed (P-HCAT). P-HCAT sent half of the simulated GMT pupil to the “Holey Mirror” which, as the name suggests, is a mirror with a hole in it.
Holey Mirror
The holey mirror is able to simulate a piston differential with a piezo-controlled mirror sticking through the hole. This light was sent into MagAO-X and the PyWFS was used to sense piston. The next phase of the project was adding post-doc Sebastiaan Haffert’s Holographic Dispersed Fringe Sensor into MagAO-X. This 1″ optic is able to interfere each segment of the GMT pupil with another then disperse them so we can back out the piston differentials. We got some very interesting results we plan on sharing in some upcoming papers!
P-HCAT aligned, not sending light into MagAO-X through the hole in the wall, but rather to a Basler science camera via a fold mirror
The next step is to convert P-HCAT into simply HCAT. This new and improved version will have a concept known as the “parallel DM.” This involves sending the entire GMT pupil onto a reflective 6-sided pyramid, a hexpyramid, which will send the light to 6 separate deformable mirrors. The central segment will pass through a hole in the center of the pyramid.
Hexpyramid
Manufacturing a hexpyramid with a central hole is no small feat. We are super excited to finally have our hexpyramid in the lab and ready to play with. This week we put it in front of an interferometer to check surface quality. To mount an optic this complex you need to be creative to say the least. See our makeshift mount below. We are happy to note the pyramid is very photogenic – it doesn’t have a bad side!
Hexpyramid mounted in front of interferometer
Piston Control is a fantastic mode of risk reduction for the Giant Magellan Telescope and we are so happy we get to be a part of this effort!
Our Dutch postdoc Sebastiaan Haffert has taught us many important terms (like “We at Toilet Duck recommend Toilet Duck!”), but the one most relevant today is zweetkamertje. As explained by Atlas Obscura, this is the “sweating room” where Ph.D. candidates in Leiden await the results of their doctoral exams.
This draft is being written (in part) during the sweating period of Kyle Van Gorkom’s Ph.D. defense.
But let’s back up a bit: Today, a pandemic-appropriate number of masked people filed in to Meinel 812 (and a much larger people joined online) to see Kyle Van Gorkom defend his Ph.D. research in adaptive optics. The view was excellent, but Jhen and Daewook had eyes only for Kyle.
Some pretty sweet mountains, you might say.
Mr. Van Gorkom (as he was then known) regaled us with tales of deformable mirror characterization and modeling. Battles won, vibrational modes damped, etc. (We will not talk about the IrisAO.)
The room was then closed for the committee to thoroughly examine him. We waited. Some of us blogged. Then, after some ritual hazing questioning, he was presented to us: Dr. Kyle Van Gorkom, Ph.D.!
A toast was called for.
The final test of the candidate is whether they can open a bottle of champagne. We are happy to report that he passed this as well, despite Susana’s evident skepticism.
And, after some initial difficulties, a toast was had! Congratulations, Dr. Kyle Van Gorkom!
As a viscacha, integral and differential calculus are beyond me. However, it does seem to be spring again here in the southern hemisphere, and my calendar indicates it has been one full year since the last October 14th we saw.
(I’d double-check my facts with some of the cientificos, but I haven’t seen them in a couple years. I hope they’re doing okay.)
This means that the Earth has completed one more turn about the Sun, and the P.I. is a year older and wiser. In celebration of his wisdom, please enjoy P.I. utterances, available where-ever fine quotes are sold.
Shortly after I began my Ph.D. studies at Steward Observatory, I noticed that the historic dome building (where they gave me my first homely office) was ringed by orange trees.
“Don’t try eating them,” I was told. “They taste terrible! They’re not edible; they’re only, what’s the word, decorative? Ornamental?”
In this post, I will seek to rehabilitate the reputation of the much maligned Steward orange.
I have been undertaking progressively more intricate cooking projects over the course of the last covid, and after SeriousEats featured a recipe for cochinita pibil on its homepage I knew I had to try. Cochinita pibil is a pork dish from the Yucatán region of México, best known to Americans as “where Cancun is.” The Seville oranges used in it are known for being sour, bitter, and generally unpalatable on their own, but impart a distinctive flavor to the dish. I tried finding them at local Mexican grocery stores, but struck out.
But… aren’t the Steward oranges sour, bitter, and generally unpalatable? Could they be the oranges I’m looking for? Fortunately the campus arboretum has cataloged every notable plant on campus, and I had only to ask:
Armed with this information, I went to harvest some ingredients. However, a problem arose.
Undaunted, I returned under cover of darkness with an improvised professional harvesting tool.
Attempting to look as suspicious as possible
The haul
The first thing I made with my sour oranges was some quick-pickled onions (another SeriousEats recipe). They were delicious. No food coloring required!
A bag of orange peels on the mantelpiece in the first act must go off in the second..
Red onion for color; bay leaf, black peppercorn, and allspice berries for flavor.
Chiltepín is a Sonoran thing, but also delicious.
Of course, juicing a bunch of oranges means you have a bunch of orange rinds left over. The Seville orange’s peel is full of flavor compounds, with writers sometimes calling it the “orangiest” orange. I couldn’t let that go to waste! Seville oranges are prized in the UK for use in marmalade, but, quite frankly, I don’t eat much marmalade. So I made candy instead.
So a-peel-ing!
I opened a new 4 lb bag of sugar for this and now it’s half gone.
That’s already two ways to eat the Steward oranges, and we haven’t even gotten to the main event yet. In cochinita pibil, the bitter (or sour, or Seville) orange juice is used in the marinade alongside a laundry list of spices—but no hot chilies. The flavor of the final dish is a bit smoky and earthy, and fairly orange in color (thanks to achiote), but you’ll have to apply hot salsa to taste.
3-4 oranges produce 3/4 cup juice
Orange you glad you didn’t get achiote all over your kitchen?
Ready, set, marinate
After a tedious overnight wait, it was time to parcel up the meat and veg. Though I’m not digging the traditional pit, I can still use banana leaves. Fortunately, Tucson’s excellent international supermarket had them in stock.
Trussed up and placed on a tray, it was time to grill. Or, I guess, smoke. (The grad-student budget version of a smoker is a grill plus a lot of babysitting.)
Smoker, meat parcels, my attempt to save thermometer probe from grill lid.
The (almost) finished product
The author with the fruits of many hours of labor
Success! Some corn tortillas and pickled onions were produced, and tacos were had by all. A poll of the individuals present for this pork fest indicated broad approval for this cochinita pibil recipe. More importantly, there were no leftovers.
To be sure, the new year looks much like the old. Pandemic still raging, all activities still online, etc etc.
Still, the days are getting longer again, and we have a few new lab members to add to the People page. Nationwide vaccination campaigns are underway, and who knows? Maybe we’ll all be vaccinated in time for observing in Chile in 2021A. (Or 2021B. Or… you know what? Let’s not jinx it.)
One of the last shows I went to last year was a triple feature: The Exbats, Tacocat, and AJJ. (AJJ played a rather grim song called Normalization Blues that seems oddly prescient considering it was only released in January of that year.)
However, in a more upbeat spirit, your song of the day / week / moment is “New World” by Tacocat.
