Back to observing in person after three years away!

Hello blogosphere! Long time no see. This past week I've been back at Las Campanas, observing with Magellan II/PFS for the first time in person in almost exactly three years (my last time here was early February 2020). Getting to reconnect with the staff, being "in the room where it happens", and experiencing truly dark skies has been wonderful, reminding me of all the reasons I love and am so lucky to have my job. A lot has changed in the past three years, including around the observatory, but the excitement of discovery and dedicated support from the staff remain super strong. 

In this first PFS run of 2023A, I'm observing with Sam Yee, a graduate student at Princeton and a frequent remote observer with PFS. This is Sam's first time at LCO, though, so it's been delightful showing him around and seeing him experience things for the first time. Per usual, our observing program has been a mix of potential planet host stars -- we're trying to detect new planets -- and stars that host transiting planets -- we're trying to measure their masses and/or refine their orbital properties. We also had two long, continuous observations of transiting planets exactly as they cross the face of their host star, which can be used to determine the spin-orbit alignment of the planets vs. their stars. This type of observation helps us infer the dynamical history of the planet, e.g., whether it is at its current very short orbital position due to smooth migration through a disk of gas or a more chaotic process like interaction with other sibling planets. We've also been pushing the instrument a bit in terms of capabilities to measure RVs of faint stars (for us this means V magnitudes of <~13). For my own program, I'm collecting data on known transiting planets, including several that we'll be observing this year with JWST to measure their atmospheric compositions. I'm excited to see the different results from this run! 

I'm training for a March marathon so tried to get in some running on the mountain while I was here. The altitude and hills make for a fun/frustrating challenge! Below I include some run photos, as well as snaps of various wildlife on the mountain. If you're a fan of flora and fauna, you can check out the LCO iNaturalist page and try to help us identify the mystery VERY LARGE arachnid we saw a few days ago!

I very much look forward to more in person observing later this year. Remote is very convenient and has other pros like a lower carbon footprint, so it's great to have and use that option. But observing in person makes a difference both science-wise and happy-astronomer-wise, so I'm grateful to be back!

The sky makes us sad, but at least there's vizzies.

 Hi!  It me.  I'm Logan, currently a 4th year PhD student at Steward Observatory in Tucson.  As Alycia said in her post, I'm writing this from the Clay control room on my 3rd observing trip down here.  But first, a tiny bio:

I'm a non-traditional student.  I got a bachelor's in chemistry from Purdue University in 2003, and earned a commission as a US Navy officer.  I served as a nuclear reactor operator on an aircraft carrier until 2008, then I returned to my hometown of Austin TX.  I then taught middle school science in Austin for 6 years.  Then a rage-quit teaching and decided to go to grad school for astronomy, but oops, it's been 15 years since I've seen calculus, and I can't even spell python.  So I used the GI Bill (yay!) to go back for another undergrad at UT Austin.  I did research with Adam Kraus on wide planetary-mass companions with Keck/NIRC2.  I graduated UT in 2019 and moved to Tucson to work with Jared Males and the MagAO-X crew.  I've put out papers on doing RDI with visual binaries on MagAO/CLIO, a candidate signal confirmed with MagAO-X (the first science paper with MagAO-X woo!), confirming that Boyajian's Star has a wide stellar companion, and contributed orbit fits of wide stellar companions to transit planed hosts in a lot of papers.  I'm currently working on accelerating stars with MagAO-X, a white dwarf-main sequence binary project with MagAO-X, and next year I will be doing an internship at NASA Ames working on modeling for reflected light exoplanet observations with GMT.

So, about this MagAO-X run.  It was supposed to be over day ago, but there was a conveniently timed truckers strike in Chile that lined up with when MagAO-X was on a truck.  So she sat on the highway or who knows where for several days, while the crew sat around the lodge.  I wasn't down yet so I delayed my flight by 4 days so she could get to the telescope and get set up.  I was staying at my parent's house at the time, and I left my dog with them while I traveled.

Unfortunately since I've been down here, observing for my white dwarf project, the seeing has been record terrible.  Most of the nights around midnight it shot up to ~2 arcsec, and was often literally off the charts.  MagAO-X struggles to work well in 1 arcsec, so this made things very difficult.  We also closed for humidity a few times.  

Here are some pics of MagAO-X chicks:

left to right: Avalon McCleod, Eden McEwan, Jialin Li, and me.

Here is a great timelapse of the Clay that Eden recorded and I stitched together:

We've also collected some great viscacha data!  If you climb down the hill just a bit from the telescope there is an abundance of vizzies living their best lives among those boulders.  We even saw two baby vizzies!!

And vizzy getting a snack and having a tiny dust bath:

Happy to report that as I am writing this on out last day on sky, that seeing is behaving and I am getting some good white dwarf images!  Wooo!

Cheers everyone!  Happy to be here.

Henrietta Swope - The Original Las Campanas Belle

Back in 2014, I did some research on Henrietta Swope, so I could give her a significant Wikipedia entry. I think of her whenever I'm at LCO, because, of course, the first telescope here is named for her (aside: it was used last night by LCO astronomer Nidia Morrell - I'm embarrassed to say I don't think Nidia has ever blogged for us here). In fact, one of the original suggestions that Johanna Teske gave for the name of this blog was "Spirit of Swope."

Swope gave the gift that allowed Carnegie to develop LCO. I just looked up the magnitude of that original gift -- $650,000. What I hadn't done before was use an inflation calculator to convert 1967 to 2022 dollars. There's an inflation rate of 791% between then and now, which would make $650K into $5.8M.   According to the Carnegie Yearbook, the total bequests she gave were $1.45M through her death in 1981 and a final bequest check from her estate in 1983.  I've long thought the unit of wealth should be the telescope!

Here is an article about Swope from the 1983 Carnegie Institution Yearbook:

An unexpected pleasure of looking at that article again was seeing the photo that included Jean Mueller. Jean was working at Palomar when I was a graduate student, as she was finishing the 2nd Palomar Sky Survey (photographic plates!) on the 48-inch Oschin telescope that is now the Zwicky Transient Facility telescope. Later, she was also an operator at the 200-inch Hale Telescope when I was doing my thesis. She also hunted comets with great enthusiasm. I always enjoyed talking to her, learning from her, and having her run the telescope. I'm happy to find that she also has a Wikipedia entry!

Belles are back in force at LCO!

I am back at LCO for the first time since November of 2019!

I spent many virtual nights here via Zoom and screen sharing during the Covid-19 pandemic, but MagAO-X is back on the telescope and its high telemetry rate and complicated interface make remote observing nearly impossible. So, I had a good excuse, I mean reason, to come back! 

And we have had quite the belle domination since I got here -- five women! Let me introduce some of them: 

 ***Jialin Li, a new graduate student on the team from University of Arizona See her first MagAO-X blog post here. Check out the photo she posted on her blog post with two of the other female students here.

***Eden McEwen, also a new graduate student on the team of University of Arizona See her first MagAO-X blog post here. 

 ***Avalon McLeod, a master's student in optical sciences at University of Arizona See her first MagAO-X blog post here. 

***And returning for her 3rd run at LCO: Logan Pearce, a graduate student in astronomy at University of Arizona and the only one of us to have actually submitted MagAO-X results for publication (go Logan!) and taker of Viscacha videos extraordinaire!  See her posts here and here, complete with said videos. 

And I make number 5. Though I think you can add the ages of two of these students and not get to mine.

 Here are Logan, Eden, and Avalon stalking the Viscacha family:

I blogged over at MagAO-X yesterday, so read about "Dripping not KLIPping" there.

Interview with Neighboring Belle, Volcanologist Diana Roman

As I was making my way to Las Campanas at the start of February, I saw on Twitter that two other women scientists I know, Dr. Helene Le Mevel and Dr. Diana Roman of Carnegie Earth and Planets Division (formerly DTM), were also making their way to Chile. But Helen and Diana aren't studying distant planets around other stars, they are passionate about understanding the only habitable planet we know of -- Earth! I asked Diana if I could interview her for the blog, and she kindly agreed, which is impressive since she was also busy with field work. Below are her responses. I was honestly surprised to recognize similarities between her work and that of astronomers -- Helene and Diana do not have much control over their experiments, they have to take what Earth gives them and come up with creative ways to piece together a complex puzzle with limited data. 

I hope you enjoy this slice of science outside astronomy as much as I did! If you have any questions, feel free to comment and I will pass them on to Diana.

1. How would you describe yourself as a scientist?

Broadly speaking, I'm a volcanologist - I'm interested in understanding how magma moves through Earth's crust, accumulates, and eventually erupts. I'm also interested in developing a better understanding of precursory signals that we might be able to measure to improve eruption forecasts. However, most of my research involves the analysis of seismic data - looking at various flavors of tiny earthquakes that result from magma and gas pushing their way through the crust - to me this is an ideal way to understand the processes I study. Almost all of my studies involve other observations - ground deformation, changes in gas emissions, or clues from the chemical composition of erupted materials - I want all the information I can get! So this means I have a wide range of collaborators who bring different expertise and observations to the problem at hand. 

2. What are you doing right now (why are you in Chile)?

I'm in Chile to install 10 seismometers and a gas-sensing instrument on Villarrica Volcano, which is just outside Pucon. The project is led by Helene Le Mevel - another volcanologist in my department who is an expert on volcano deformation and on using minute changes in the local gravity field to detect magma and/or gas rising towards the vent. Villarrica is what we consider a 'lab volcano' - since it's always active it's a great place to test out new approaches to monitoring volcanic activity. The main aim of the project is to determine whether continuous monitoring of the gravity field very close to the volcano can help us detect subtle changes in the amount of magma just below the surface - the seismic and gas data I'll be collecting will help give independent constraints on this. The project is very technically challenging - a gravimeter is a delicate (and expensive) piece of equipment, so trying to keep it running on top of a windy, rainy, and active volcano (lots of corrosive gases) is a huge logistical challenge, but I'm confident that if anyone can do it, it will be Helene! 

We'll be returning a few times a year over the next two years to check up on our instruments and fix any problems before we remove them from the volcano. We are fortunate to be collaborating with OVDAS (the Observatorio Volcanológico de los Andes del Sur) - the OVDAS scientists have deep knowledge and know-how about this volcano and how to monitor it, and their advice and participation in the project is essential and appreciated. 

Hélène Le Mével packs for a year-long study of Villarrica, an active volcano in Chile. Among the standard outdoor equipment are tools for measuring volcanic activity including ten seismometers, five infrasound monitors, one multiGAS machine, one GPS antenna, and two gravimeters. Credit: Carnegie Science | Katy Cain
Read the story behind this photo here.

3. Why is this work exciting to you?

Villarrica is an extremely active volcano, so I anticipate having lots of seismic signals to analyze. Furthermore, while I'm only leaving my instruments out for a year, the volcano has been monitored and studied for decades, so there is an opportunity to fit my observations of seismicity patterns into a longer time series to understand how the volcano's activity cycles over multi-year periods. 

On the edge of Villarrica! Credit: @HLeMevel on Twitter

4. What do you hope to learn on this trip, or from the data you collect? 

Ultimately, I'm hoping that the data I'm planning to collect will allow me to assess what types of precursors exist at Villarrica and similar volcanoes. Because these volcanoes are continuously active, it's more of a challenge to determine when a major explosion is about to occur, as the levels of seismicity are always high. So I'll be looking for very subtle changes in the seismicity prior to any explosions that occur during our experiment - perhaps differences in the direction of fault-slip that indicate a change in the amount of stress the magma column is producing on the rock, or subtle changes in the frequency content of seismic events that indicate a higher gas flow through the upper parts of the system. The fundamental challenge in volcanology is that we can't plan a precise experiment - we have to work with whatever the volcano gives us. So it's always unclear what exactly we'll be able to learn until we see how the activity evolves once we have our instruments out, or what we'll learn. 

5. What is the most fun aspect of your work, overall and/or on this specific trip? 

My work takes me all over the world - I've worked in Alaska and Hawaii, but also Iceland, Italy, Nicaragua, Mexico, and now Chile. I love these opportunities to travel and spend time in different places. Doing fieldwork in a country is a great way to learn about it - we work closely with Chilean scientists, and we get to see a lot of 'normal life' in Chile - very different than being a tourist. I love meeting people during my work - not only the local scientists, but the people who live on and around the volcanoes I study. Hearing their stories and their perspectives about the volcano is always fascinating! 

6. Anything else you'd like to add?

There are eight of us on this trip - myself, our project leader Helene, Kathleen (a postdoc at Carnegie), Dani (a PhD candidate at Drexel University), John West (an independent scientist from New Mexico), Giovanni Pineda and Patricio Mardones (engineering students from the local university), and Loreto Cordova (a geodesist from OVDAS) - so our team is more than half women! 

Some of the team members on this expedition. Credit: @HLeMevel on Twitter

Cross post alert!


MagAO-X PI and former grad school classmate of mine Jared Males reminded me that there is some awesome blogging by women scientists happening over on their blog. Please go check it out!

My First Visit to Las Campanas!

I am a fifth year grad student at Michigan State University (MSU), and this summer, I got an amazing opportunity to run a nine night long observing run on the du Pont telescope at Las Campanas Observatory in the Vallenar region of the Atacama desert in Chile. I have had several remote observing nights through MSU on the SOAR (Southern Astrophysical Research) telescope as a grad student, but I had never been on site for observing (or even had more than one night in a row of observing). When I was asked to manage the second half of an observing run on the duPont telescope for several folks at the Carnegie Observatories, I hesitated at first. Prior to this summer, I had never been out of the US, and the prospect of flying to a remote mountain in a country where I didn’t speak much of the language was very intimidating. I definitely considered not taking this opportunity. However, I knew that this experience was too cool to pass up, and I’m so glad I did it.

The view over La Serena from the El Pino office before heading up the mountain

After about 30 hours of travel from Michigan to Las Campanas, including a bus ride, 3 flights, and two shuttles, I finally made it to the mountain just in time to meet up with Jeff Rich (from Carnegie) who would show me the ropes on the telescope for a few nights before he headed home and I took over. He also gave me a great tour of the grounds and telescopes, showed me the best spots to look out for the local wildlife, and demonstrated the “ringing rocks” out by the duPont telescope. There is something about the composition of the rocks and how they have broken that means they ring like a bell when hit just right. Since Las Campanas translates to “the bells” in English, I believe the rocks are at least part of the origin of the observatory’s name.

After a few days, I went from shadowing to running the telescope, and my nine night run began. On my first night alone, I met some wildlife companions on the road (see photo, just drive slow and they move eventually!) and I watched an amazing sunset before kicking off observations for the night. 

Burro friends on the road to du Pont!

A beautiful sunset seen from the du Pont telescope parking lot

Because winter weather is generally marginal for observing, I thought it would be unlikely that we would have good enough weather for nine nights in a row. However, we were fortunate to have only one partial night that was too cloudy to observe and a bit of time over a few nights where the wind speed was high enough that it was unsafe to open the dome. The fun part about observing for others is that I got to really see all the things that the Wide Field CCD (WFCCD) on duPont can do. I took spectra to help follow up and classify supernovae and broad band images of supernovae to help determine what was needed for follow up spectra for the All-Sky Automated Survey for Supernovae (ASAS-SN) project. Spectra are taken by passing the light through a narrow slit and spreading it out into its components (much like sunlight through a prism), and they are used to learn what elements and ions make up the object we are looking at. I also took many spectra in a row stepping one slit width across the face of a few beautiful nearby galaxies for the TYPHOON project to map the stars and gas as well as single spectra searching for tidal disruption events (when stars get close enough to a black hole that they are torn apart). The most difficult challenge of the run was mounting a custom cut slit mask to do some multi-object spectroscopy on a galaxy cluster! 

Rachel standing next to the 100 inch du Pont telescope

 On the last night, I had a few open hours of observing time, so I took some broad band  images and some spectra for two of my own galaxy clusters. Broad band images are taken using filters that block out emission at certain wavelengths, particularly those from the  atmosphere, so we can learn where different wavelengths of emission is coming from. I study the hot gas in galaxy clusters and nearby early type galaxies in the X-ray and optical wavelengths. For these two objects, I was looking in the optical wavelengths to identify the brightest, most massive galaxy in the cluster (known as the BCG) to compare to the existing X-ray data. Throughout the whole run, I had the support of the amazing telescope operators and the folks from Carnegie, and it made for a very fun and exciting observing run, though I was exhausted by the end of the run. Fortunately, the never-ending supply of espresso, tea, and delicious Chilean snacks kept me going throughout the run. While the winter nights were long and took most of my time, I did get the chance to test the gym on the mountain (it could do with a squat rack, but was still enough to keep myself on track with my powerlifting training) and enjoy dinners in the lodge. It was fun to chat with other astronomers about what we were observing and cross our fingers for clear skies.

The chefs at Las Campanas are most known for their empanadas, but they make tons of other delicious food!
This was chicken soup, stir fry, and tiramisu.

Having the opportunity to visit LCO was unforgettable and I’m so grateful for the opportunity. Getting to work on location with a telescope and balancing the needs of several different people helped me learn that I have strengths I didn’t know I had and opened my eyes to potential career paths as I near the end of my PhD. I had never realized that there are people who both manage telescopes and get to do their own research, but now I’ll be looking for those jobs as I finish my thesis work next year. In short, I am so glad that I went and would encourage other astronomers to do the same!

Foreground: The Magellan telescopes (Baade and Clay)
Background: The du Pont and Swope telescopes

First time at LCO

I’m Sunny, a junior physics major at Pomona College. I was very fortunate to be invited to LCO by my mentors from the Carnegie summer undergraduate program. For several nights this November, I shadowed my mentors as they observed targets for an ongoing tomography survey.

Me with the Magellanic Clouds in the background!

This past summer I worked exclusively with processed data to make 3D tomographic maps of the high redshift IGM. I hadn’t looked at spectra much, so on my trip to the Magellan telescopes I was hoping to learn more about the properties of the galaxy spectra used in making tomographic maps. I was also really excited to learn about observing in general, as this was my first observing run.

I ended up most enjoying the time I spent in the Baade control room, learning about the interface and the procedures and strategies involved in observing. I learned about spectroscopic calibrations and was then able to take some on my own! I also learned about taking twilight flats, which are useful for getting calibration frames in the UV (as our targets are UV-bright galaxies). Several other highlights of my experience at LCO include holding (a broken version of) a grism customized for our targets, seeing an IMACS slitmask packed with spectra, and watching the telescope move.

Visiting LCO was amazing! I very much enjoyed learning about how the data I used was taken. And on the non-astronomy side of things, I got to see some interesting animals (like the viscacha shown in the low-quality photo below).

A long overdue observing run

Figure 1: Diana and Clay.

Almost eight years after my first on-site observing experience (at the CTIO 1.0m), here I am, wrapping up my second observing run ever. This time, I've been trusted with a much larger telescope (Clay, see Figure 1) and a precious instrument (the Planet Finder Spectrograph - PFS).

Of course, I had to first get trained on PFS (thanks Johanna! thanks Steve!). It's been a learning curve. Here are the things I have done this past week that I had not done before:
- observed on site with a spectrograph;
- filled the instrument Dewar with liquid nitrogen (see Figure 2).
- drove an automatic car that is trying to be manual.

This observing run has certainly posed some challenges, both to the PFS team and to me personally. 

Figure 2: Filling up the PFS Dewar at 6:30am.

On my first night of training, we sent a command to move the iodine cell in the light path in order to complete calibrations and begin observing. However, the iodine cell would not move. Upon inspection, we discovered a glycol leak near the area where the PFS calibration lamps and CCD controller are. We suspect the glycol lubricated the iodine cell motor, disabling it from moving the iodine cell. The mountain crew rushed over and did a fantastic job cleaning up the leak. Following the cleanup, we were able to complete calibrations and start observing, but we did lose about 3 hours. 

I usually use space-based data or observations from robotic telescopes, which is why I do not go observing very often. Adjusting to the night schedule was a personal challenge for me, and it took me a couple of days to adapt. At first, in the morning at the end of observing, each of the last few steps before bedtime seems like an insurmountable challenge: getting the calibrations right, filling the Dewar with liquid nitrogen safely, driving back to the lodge.

In the end it was all worth it for the learning experience, but also for the wildlife (see Figures 3 - 8), scenery, and sense of escape (see Figure 9).

Figure 3: Burro.

As a "bonus", we had good weather and seeing (at least during the week I was there!), and we acquired numerous spectroscopic observations that will be used to measure the masses of newly-discovered exoplanets.

Figure 4: Vulture (thanks George!).

Figure 5: Vizcacha.

Figure 6: Guanaco (thanks George!).

Figure 7: Zorro.

Figure 8: Small owl.

Figure 9: Our galaxy.

Night 2... Let the observing begin!

So last night ended up as a total observing bust, but never fear there was still tons of fun to be had! We tried to wait out the high winds, somewhere between 50-60ish mph all night, we got to tweeting up a storm. We also decided to venture out to the catwalk, while the winds were at 60 mph, because when your advisor says,"You should go on the catwalk with the wind! It's fun. And a little scary. The moon will brighten you", you oblige.

And with that I bring you the greatest wind photoshoot.... The live photo really does the first one justice. I felt like if I let go of the railing that I would have literally blown away. Our collaborator said that we should fly a kite and I responded with "I in fact was a human kite."

On the catwalk between Baade and Clay

Post wind hairdo!

Night 2 started out much better with the winds dying down... but then the humidity struck! At one point we had all the weather problems we could have had at the time wind, clouds, and humidity. The text message anger was real on our collaborators end and the gifs he said definitely did it justice. Once the weather got better we could open and then we were on a run. 14 targets down and then dun dun dun the wind came back with a vengeance! And now we wait. Hoping for the wind to go away but you never know with the winter weather. Hopefully Victoria's post will have a happy ending for us and hopefully all of the fabulous additional targets!

A Chile and Windy Winter Night

BDNYC in da House! This is my third trip to LCO, but my first time teaching someone else how to use the instruments on the Baade telescope. My partner-in-crime for this run is Victoria DiTomasso, who recently graduated from CUNY with her BA in physics this May. We have two nights and are planning to use FIRE, the NIR spectrograph, and Fourstar, a NIR imager, to observe some awesome brown dwarfs.

Victoria and I outside of El Pino

My journey to LCO started with a sad amount of sleep for me on the long flight from NYC, but no worries I immediately passed out on the SCL-LSC flight surrounded by a family with so many children. While I waited for the flight from SCL-LSC we found a few other astronomers that were going to Las Campanas as well, making our new group woman dominated- 4 female astronomers and one male astronomer. My adviser said we'd be the only women on the mountain, but ha we are not! I have never been the only woman on the mountain, since our research group runs deep in amazing women.

As stated by twitter, the IBMT or 

the itty-bitty Magellan Telescope

When we arrived in La Serena we had to wait a few hours before we could go up the mountain. While we waited we got to explore a little of El Pino and found a cool scale model of the GMT. After that we took a walk to get some empanadas and enjoyed the warm sun and fairly nice weather, the last to be seen of  until Monday when we come down (the weather of course, I am sooooo looking forward to empanada Sunday!).

The first night on the mountain was supposed to be the night I worked on switching over to the night schedule by staying up late.  But because I was so exhausted from the lack of sleep on my flight my plan of action changed. Instead of trying to stay up late, I went for trying to sleep in as late as possible. Sucess! I made it to 12 and a half hours of sleep! Yea for naptime!

The winds sometime at the start of the night. Gusts of 58 mph! Most of the day was like this, but slightly less windy.

The selection of teas. There is one made of a plant that I have
never heard of, which will definitely be my next cup!

After lunch on our first night of observing (today!) we went up to do calibrations and a telescope photoshoot. Check out Victoria's blog post for those photos! The photo that I really should have taken was one of me and the wind. No lie I was blowing away! I hoped for the wind to die down over the day not only for my safety as a tiny person, but for good observing. While I showed the telescopes to Victoria we could feel the wind pushing our tiny little blue car, so you get the picture.

Mars is keeping warm and staying hydrated 

while we wait out these winds!

As the sun set we knew that we would be in for a long night. The night so far has been observing the tea selection (oh so many!) while we wait for the high winds to die down.

Hoping the weather gets better but the TO said it looks bad for the next two days aka our entire run  :( Luckily, its still early on in the night. Updates to come tomorrow as we start night two of the run!

The weather is good, but....

From left: Me (Juliette), Johanna Teske, Sharon Wang, and

Erin May in the Clay telescope dome. Erin and I are

observing on Baade this week, and Sharon and Johanna

are observing on Clay.

Hi! My name is Juliette Becker, and I'm a graduate student at the University of Michigan. This week is my first Magellan run, using IMACS to look at a white dwarf with a disintegrating planet and also at some transiting planets. I am observing alongside Erin May (a fellow UMich graduate student and IMACS pro!), and we have a four-day run this week. Johanna Teske and Sharon Wang are observing on Clay this week, so it's ladies' week at Magellan!

Erin has in the past had terrible luck with weather at Magellan; it seems to be cloudy or raining every time she comes to observe (the running joke is that she's "cursed"). We've been checking the forecast for the last few weeks, getting nervous when it looked like there might be clouds and getting happy when the forecast became more favorable. When we arrived here Sunday evening, the weather was pretty good, with just some scattered clouds. The forecast looked favorable!

Monday night, the weather got even better. We were able to get on sky on-time and observe both of our targets for the night! There were some scattered clouds, but it wasn't too bad. We reduced some preliminary data, and things were looking pretty good.

Pretty good weather, with only scattered clouds!

Come Tuesday, we were excited to get more data on our targets: it appeared that the "curse" was broken, because the weather was great! We did our calibrations Tuesday afternoon, headed back for dinner, and returned to the telescope before sunset.

When we arrived at the telescope, several of the local Magellan engineers and instrument specialists were in the control room, looking concerned. The guiding wasn't working, and they quickly determined (as Erin and I looked on in horror) that the reason for this was liquid on the camera. My first thought was "Liquid? How did that happen? It hasn't even been raining!", but things quickly got worse...

The engineers determined that a hose had a nick in it, resulting in glycol spilling everywhere. And it wasn't just a spill - it had spewed all over the instrument and the local area, resulting in a GIANT MESS:

Video of the aftermath of the spill, courtesy of Gabriel Prieto.

As the engineers worked hard to fix the spill and get the instrument functioning again, things were not looking good. It seemed like IMACS would not be functioning again for at least two nights, but one of the engineers mentioned that they could unplug IMACS and plug in another instrument. Erin and I scrambled to get backup targets that we could observe using another Baade instrument, so as not to waste valuable Magellan observing time!

As 11pm approached and the engineers continued to work, we had come up with a list of backup targets for FIRE, calibrators, and an observing plan. Even if IMACS wasn't working the next night, we would be able to observe on FIRE. At this point, I was totally convinced of the existence of Erin's observing "curse." Clearly, the curse hadn't been able to control the weather this time, so it had decided to take another approach...

But just as we almost reached the point at which we would not be able to observe our transit, the Magellan crew came back from the dome with good news: they had a temporary fix for IMACS, and we could get on sky after all! We finally got on sky ten minutes before the transit we were observing, thanks to the herculean efforts of the telescope operators, instrument specialists and engineers on site. The guiding system was out of commission, so our telescope operator Alberto had to focus the telescope manually all night. In the end, though, we were able to get data for our second target of the night.

The lesson I've taken away from this trip is that it takes more than good weather to have a successful observing run: you also need a talented crew of telescope operators, instrument specialists and engineers ready to save the day if something goes wrong!

Interview Cross-Post

I'm back at Las Campanas with the MagAO team! But tonight I'm just cross-posting an interview I did for the DTM website. Read the Interview

Using the tunable filter

One of the most difficult experiments we did in my undergrad physics class involved calibrating a finicky Fabry-Perot interferometer. The MMTF tunable filter on IMACS at Magellan works on the same principles, where you precisely calibrate the alignment and spacing of two parallel plates to allow only a small range of wavelengths to pass through. After talking with fellow Carnegie postdoc Rosalie, we had an idea for a possible project which would involve the tunable filter, and decided to go for it.

We allotted ourselves a big chunk of time in the first afternoon to get everything set up for the first time, and after some skype help from Ben Weiner, got our calibrations all set for the night. We were pretty happy about this, come sunset:

(Decker and Rosalie, after successful calibrations, trying not to think about the clouds in the background)

After some threatening clouds, things cleared up enough to start taking data, and we got on our science target:

(Science data with the MMTF!)

I'm super excited about what we're seeing in the quick-look of the data, and looking forward to seeing what happens after the full reduction!

Unfortunately, the clouds did end up rolling in halfway through the night:

(Clouds seen on the satellite image over the sad red dot which is us)

So, we'll have to try again tomorrow night and hope for clear skies.