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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.

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.

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.

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.

Logan figured out how to get Vizcachas to be our substitute Easter Bunnies. they’re going great.

It is quite a late morning while I am writing this blog post. We had a very successful first night of commissioning of VIS-X. VIS-X is the Visible Integral-field Spectrograph eXtreme (VIS-X). Of course everything we do is extreme. So the spectrograph also had to be extreme. VIS-X is the project that I have been working on in the last two years. Its goal is to take spectra of exoplanets and use that to characterize what’s in them (of course everyone wants to search for signs of life ;-)). After multiple day of aligning, I finally was able to get everything up and running. And we were able to use VIS-X on-sky!

One of the challenges with VIS-X is the acquisition on-sky. MagAO-X already has a small field of view of a couple arcseconds and, the field of view of VIS-X is even smaller! We can only see things with 0.55 arcseconds, that’s about 1/7000th of a degree.

The first multi-spectral images of VIS-X + MagAO-X. The colors correspond to the wavelength range of 450 nm (blue, left) to 950 nm (red,right). The next few night will be very exciting when we will try VIS-X on more challenging targets.

Using new instruments and observing is always exciting. However, sometimes observing is just a lot of waiting and it can be very tiring. Everyone deals with that in their own way.

VIS-X has two different observing modes. A low spectral resolution mode and a high spectral resolution mode. We did the commissioning of the low-res mode last night and to switch to high-res, I have been aligning after a full night of observing. My current feelings are well captured by this dutch song of today.

It finally feels like we’re starting to settle in here. We have begun doing hours-long observations of science targets for observers, and that means we can actually take a breath, catch up on email, and bond with our friends at LCO.

While having our dinner we were graced by our friend the Burro who likes pets.

Sebastiaan had to negotiate passage to dinner.

And Logan got her first nose scritches in.

Sebastiaan then had to pay the toll to get by.

And Avalon made friends too.

Our telescope operator Hernán Nuñez ( a hero of MagAO runs past ) told us that he thinks these guys have basically been abandon up here for a couple of years. This one, at least, clearly trusts and even likes humans, so it doesn’t seem like they’ve been wild their whole lives. Our friend might be a little lonely.

After our fun dinner party with the Burro, I walked up to the telescope for the first time since we went on sky. On the way up I saw our friend Povilas — It’s great catching up with old friends after such a long absence.

The night started with some VIS-X work by Sebastiaan.

Where’s Sebastiaan? He’s in this photo working on MagAO-X.

We started work on a nice bright star, part of Logan’s program. This was a great chance to put our high-speed low-drag coronagraphic mode to work. In the below image you can see the usual MagAO-X control panels. The lower right desktop shows the simultaneous images with a coronagraph disk occulting the star so we can look for companions. The 4 spots forming a cross are made by our deformable mirror as fiducials for alignment and photometry. The right-most image is our “low order wavefront sensor” camera, which is imaging light reflected from the coronagraph mask (the thing making the dark spot in the center of the other two images). We use that light to keep the spot centered at high speed (in this case 600 Hz). Fully understanding and optimizing this mode of observing is the key to my main science goal for MagAO-X, so it’s really exciting to see us getting started on it with a real star.

Here’s a close up view. Here the “satellite speckles” have green lines drawn between them, and the coronagraph is centered on the cross.

While we worked inside on our tiny little field of view, the great big outside sky was putting on quite a show:

In the desert. A horse with no name. I can still remember my name. But the day of the week is already gone.

To aid the MagAO-X team members I’ve left behind, I’m making a post of my transit from LCO back to Tucson, AZ. Here is a list of the necessary things to travel to the U.S.:

• A passport
• A credit card or other valid form of payment in Chile
• A valid COVID-19 rapid antigen test with a negative result
• The slip of paper Chilean emigration and customs gave you upon entry to their country
• A lot of time on your hands

The road from LCO to LSC

The road from Las Campanas Observatory to La Serena has some pristine stretches of mountain and coastal areas begging to be explored. My driver, Juan, was nice enough to indulge my desire to practice my long dormant spanish-speaking skills. Two and a half hours went by in an instant. (I also witnessed a small owl dancing and singing on the side of the road at the behest of Juan, and a short glance at a Chilean wild horse.)

Another rapid COVID-19 test abroad

Juan took me directly to the testing site which was on the corner of a strip of stores in the lot of a gas station, featured below.

At the check-in desk of the lab, Vital Medical Center, I was asked why I was there, as well as for my passport and a phone number and an address of where I’m staying in Chile. I gave them the El Pino office address details, as well as the number for Dave Osip. I think Roberto’s number would’ve been a bit more pertinent to provide. I also told them I needed the test for today, as I was leaving in the afternoon from LSC.

They charged about $22.000 CLPs to my credit card for the antigen test, which corresponded to about $27.00 USD. I went around the corner to the nurse’s station, had my nostril swabbed, and sat and waited for about 15 minutes. Then they printed my test results and handed them to me in an envelope.

Afterward Juan took me to El Pino, which was about a 10 minute drive away.

The Luxurious El Pino

We pulled up to a gated entry way to El Pino and entered, headed up the driveway, and made our way to Roberto’s office. Roberto greeted me with a fist bump, and we made our way to the dining area and hotel.

WiFi is available, and actually my laptop automatically connected to the lco-staff network. I successfully ssh’d into exao1 just to verify the network was the same. I completed the Delta FlyReady documentation and even though they verified my negative COVID-19 test result in time, it did not matter to LATAM. In other words, I had to check into my flights at the LATAM airlines check-in area at La Florida airport (LSC). Because of this, I opted to leave half an hour earlier than I was originally scheduled, but I don’t think it mattered in the end.

Going back to the U.S.

The drive to LSC took a little over 10 minutes, and was provided by an LCO staff member. Once I was inside the airport, I checked in at LATAM and checked my bag, keeping only my backpack. They required my passport and COVID-19 negative test result. Then they printed all of my tickets and sent me to pass through security. Security didn’t have a line, so I was at my gate about 15 minutes after I arrived at the airport.

The flight to Santiago was on time and uneventful, and in mostly understandable English, a flight attendant stated that checked luggage for international connecting flights will move on toward its final destination before customs in another country. Disembarking the plane led me to a very long corridor to walk down towards ‘Domestic Arrivals’. At the end of it, just past the bathrooms, there is a wall with a Victoria’s Secret ad from which you should clearly only turn right. This ushered me to a more open area with a plethora of signs indicating how to find the international terminal. For example, here is half of two signs combined to provide a nice map of where to go, and a text description for international connecting flights.

Once I exited the domestic terminal to outside, I ended up taking the left path from the map above. I was asked at least four times on the way out if I needed a taxi. I did not. I walked across the crosswalk and followed signs to the international terminal. Once again, it was very easy to figure out where I was going. I even walked past the Holiday Inn that Laird recommended I stay at to kill time. I will argue the new international flights building is just as nice to kill time in, and in doing so, I was already through emigration and customs awaiting my flight.

Once inside the international terminal, I went upstairs and into emigration and customs after I found the corresponding gate information for my next flight.

Emigration required my passport, my boarding pass, and that slip of paper from Chilean authorities upon entry to the country. I then passed through security and into the international airport. My flight information was not quite up-to-date yet, so I wandered around the airport wondering if I’d ever receive an update about my checked luggage. Eventually, I did.

When it came time to board my flight from SCL to ATL, it turns out the airline wanted to re-issue the tickets for my remaining travel. I was not aware of this ahead of time, so I had to wait as many people in my boarding section went ahead of me. To issue my new ticket, they once again required my passport and negative COVID-19 test results. As a reminder, dear reader, I only had my backpack, so boarding order did not affect me. This may not be the case for you!

You’ve probably seen this all before

10 hours later, I arrived at ATL. I passed through emigration where they asked me for my passport and why I went to Chile (traveled to LCO to use the Magellan Clay telescope for MagAO-X instrument commissioning and observation), collected my checked luggage from baggage claim, then through U.S. Customs and re-checked my luggage before I went through a final security checkpoint and off to find my final gate. During baggage claim, I came across a different type of drug-detecting dog unit.

It is faster to take the train to the various concourses, but after a 10 hour flight, I decided to walk. The Charlotte, Atlanta airport is huge! My final flight to Tucson was delayed a bit, but my luggage made it (confirmed via another Delta app update), as did I. More than 24 hours of travel later and here I am, back in lovely Tucson. The song of the day mentions Tucson if you listen closely enough, or watch the lyrics (Closer, The Chainsmokers ft. Halsey).

Today was a great MagAO-X day. We had great seeing and things worked well, we were able to get a lot done today and make some nice science-y images!

Engineering continued again tonight with a smattering of science. Tonight we worked on commissioning the non-redundant aperture mask (NRM), which is a technique for achieving high resolution images from the ground. Our collaborators Dr Josh Eisner and Dr Jordan Stone joined us via zoom to commission MagAO-X’s NRM observing mode on a bunch of their science targets.

The top image here shows science camera 1 (left) and 2 (right) during the NRM imaging run. The image on camsci1 is continuum (kinda like the baseline emission from the source) and on camsci2 is H-alpha, a hydrogen emission line that is very bright when the star is accreting (eating up gas and dust). It doesn’t really *look* like a star right now, and is all blurry-looking, because of how the masking works. Some fancy math is needed to reconstruct the images into more eye-pleasing and scientifically meaningful images.

We also got to look at one of my science targets. I am trying to detect some white dwarf stars. A white dwarf is the hot core of a star that remains after the star has evolved and shed all of its outer material (called the envelope). White dwarfs are interesting to me because they can serve as an important probe of planet systems at the end of a star’s life. The surface of a white dwarf is either pure hydrogen or helium, so if you see any other materials in the spectrum of a white dwarf (which astronomers call “metals”), it has been recently deposited there by planetary material or debris eaten by the star!

And we ended the night with some lovely images of Baade’s window, an area of dense stars towards the galactic center and with little dust that we use for measuring the astrometry, or the position of stars. One of the important things to determine about your instrument is how distances and angles in an image relate to distances and angles on the sky. To do that, we need to take images that contain multiple stars for which we already know their on-sky astrometry, and compare that to measurements in an image. So you want a crowded field with a lot of stars, so that you can have many stars fall within your image, and with existing well-documented measurements between the stars. Baade’s window is a good target for this, so getting many good images of it in all our filters is a top priority.

Our friend Carlos showed up for dinner again and struck a commanding pose in front of the sunset. Good boy.

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The moon is waxing towards full and lighting up the mountains all night here. The song of the day is Who Built the Moon? by Shinyribs