Stephanie JH Deppe, PhD

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Astronomy, Telescopes, and Bears, Oh My! (Part 1)

….ok, I never actually saw the bear….but we were thoroughly warned before (and after) we arrived at the mountain that there was a resident black bear roaming the premises. And I can confirm that the bear was sighted during the time we were there, though not by anyone in our group.

This May, I had the fantastic opportunity to travel to Kitt Peak National Observatory, located about 50 miles southwest of Tucson, AZ, to teach a great group of undergraduates about ground-based observatories. Over the course of four short weeks, the students developed a science idea to test, wrote a telescope observing proposal based on that idea, took their own data using two telescopes at Kitt Peak, reduced and analyzed the data, and presented their results. And this was all done while having to sit in lectures, go on tours (both on the Kitt Peak site and off), and participate in several other off-site excursions! Thinking back, it’s really amazing how much the students were able to accomplish, and to such a high standard! (Can you tell I’m proud of them?)

As an instructor, I was fortunate enough to get an all-expenses-paid trip (plus a paycheck!) to a gorgeous mountaintop with greenery and wildlife, awesome telescopes, and beautiful sunsets. It was probably the best experience I’ve had in graduate school so far, so I am writing this blog post to memorialize it and share it with all of you! I’ll be splitting this experience into several posts, due to the jam-packed schedule and sheer number of things we were able to do and see over the course of our month at Kitt Peak. So stay tuned for subsequent posts in this series!

Oh, and make sure you check out my photos, too!  Stephanie’s Obnoxiously Long Kitt Peak Photo Album


Sunday, May 7th

After pretty smooth travels (aside from a two hour delay in Minneapolis) I FINALLY arrived in Tucson! This was my first time in Southern Arizona, so I was excited to see this new place. Of course, the first thing I noticed was all of the brown – brown ground, brown trees, brown weeds….and then Sally (the professor of the class) said as we were driving up Kitt Peak the first time, “Wow, it’s pretty green here still!”…WHAT? After she said it, I could see some green in there, but coming from Michigan pretty much anything else seems brown by comparison.

The students were assigned dorm rooms in pairs, while Sally and I would be staying in the guest house on site. Accommodations were basically what you’d expect from a facility constructed in the 1960s – wood paneled walls, fluffy carpet, a single ethernet modem that was very obviously wired after the house was built….not even kidding, there was an obvious hole in the exterior wall. Nonetheless, I was happy to be staying in a place with my own bedroom, a kitchen, and internet access (evidently the dorm where the students stayed didn’t even have ethernet! #firstworldproblems?).

After settling in a bit, we all piled into our giant 15-passenger van (a completely necessary vehicle with 12 students and 2 instructors, thankfully I didn’t have to drive it) and headed to one of the two telescopes we would be using the following weekend (the Hiltner 2.4-meter and the McGraw-Hill 1.3-meter) to shadow an astronomer who was using it for the night. It was actually super cool to see astronomy behind-the-scenes on the very first night at the observatory! We didn’t hang around too long though, due to our jet-lagged brains screaming at us for being awake at (what felt like) 3am…

Looking out over Kitt Peak toward the Mayall 4m telescope


Monday, May 8th

Day 1 of class was pretty uneventful, with a general introduction to the site and the structure of the class. In general, each day consisted of an AM, PM, and evening activity – these consisted primarily of lectures and site tours toward the beginning, but transitioned to more off-site excursions toward the end. More on those later! We were welcomed to the observatory by none other than the director herself, Lori Allen (side note: how awesome is it that the director of a major American astronomical observatory is a woman?!). We learned from her the difficulties that come with funding an observatory whose largest telescopes are now considered painfully mid-sized, and all of the hoops they need to jump through. The National Science Foundation was actually about to close this historic and beautiful observatory until its largest telescope was chosen to be used for a huge upcoming survey, DESI.


Tuesday, May 9th

Day 2 was a bit more interesting than Day 1, with tours to two of the bigger telescopes on site planned – the 2.3-meter WIYN telescope and the 4-meter Mayall telescope (where DESI will be installed). These two scopes are quite different in their designs; for example, the Mayall lives in an 18-story concrete/metal building, while the WIYN lives in a 4 story building….this has to do primarily with the way the telescopes are mounted and controlled. In the old days before advanced computers, it was much easier to align one of the telescope’s axes of motion with Earth’s axis of rotation. This way, when an astronomer was tracking an object across the sky, she only had to worry about a single axis of rotation.

The issue with this design is that by having one axis aligned with Earth’s rotational axis, one ends up with the weight of the telescope somewhat suspended in midair. Consequently, the supports for the telescope need to be much bigger in order to securely support its weight. A better design is one that doesn’t have to fight gravity as much – instead, have one axis be horizontal to the ground (like a merry-go-round) and have the second axis be a simple up-and-down movement. Unfortunately, this design was not practical until more advanced computers came along that could precisely control the two axes simultaneously in order to track an object across the sky. Now that that’s possible, however, telescopes built today use this second design. The pictures below show these two designs: on the left is the first and on the right is the second.

The Mayall 4m telescope’s equatorial mount

The WIYN 3.5m telescope’s altitude-azimuth mount

We wrapped up the rest of the day with a couple of lectures and a meal in the cafeteria. I have to say, I was very pleasantly surprised by the quality of the food up at the summit – I had heard horror stories about the cafeteria-grade food by some colleagues, but I enjoyed every meal throughout the month!


Wednesday, May 10th

I think by the third day, the students were starting to become aware of the work that would be required of them during the month…this was the day they needed to choose a telescope on-site that they would write five pages about, with only a couple of days until their project observing proposals were due, complete from choosing a topic to study to determining the amount of time and the instruments they would need on the telescopes to describing the science product they expected to obtain at the end. Let’s just say I much preferred the instructor role, available to help when needed but also able to sit under a tree with a book when I wanted…

In the evening, we had the chance to head over to one of telescopes we’d be using in just a couple of days, the McGraw-Hill 1.3-meter at the MDM observatory (fun fact: “MDM” stands for MIT, Dartmouth, and Michigan, in honor of the founding institutions of this subset of telescopes. MIT has since left the collaboration, and the remaining institutions have been joined by Ohio State, Ohio University, and Columbia University. Yet it’s still called MDM…astronomers, I tell ya). Was this the start of our observing run? No, actually we were going to watch an astronomer at the University of Michigan begin his night of observing from the comfort of his own office. This “remote observing” is quite bizarre to witness – imagine you’re sitting in a room surrounded by the computers that control the telescope, yet the mouse is moving on its own, the lights in the dome turn on and off by themselves, and the telescope just starts moving….yes, obviously there was a human controlling these things, but it was strange knowing they were doing so from 2,000 miles away!


Thursday, May 11th

Thursday was a pretty chill day overall, at least for Sally and I. For the students, it was a combination of stressful in the morning as they put the finishing touches on their observing proposal drafts and relaxation/decompression after said stress. The afternoon saw a brief lecture from me, but the evening is when the real fun started.

We piled into our 15-passenger van once again (this became a very common theme throughout the month…I had a love/hate relationship with that van) and made our way to the MDM observatory to get familiar with the instruments we’d be using. We of course watched the sunset before getting to work, as all astronomers do (what can we say, they never get old!). I’ve come to the conclusion that no sunset compares to those seen from mountain tops in the desert – the reddened sunlight just mixes so perfectly with the dusty brown/red landscape, and mountains are always gorgeous photo targets. I have no idea how many sunset pictures I took over the course of the month, but this one has to be my favorite:

Sunset from the 1.3m telescope at MDM Observatory

After sunset, we began standard procedures to prepare the telescopes for a night of observing. We weren’t officially scheduled to begin observing until Friday night, but we wanted to be familiar with the instruments and procedures before we actually had to do it for real. I took the helm at the 1.3m, while Sally was in control at the 2.4m. The start up and shut down procedures became second nature by the end of our four nights at the scopes:

  1. Fill the detector dewar with liquid nitrogen in order to keep it cold all night.

  2. Open exterior doors to the dome to equilibrate the air temperature inside the dome and reduce turbulence.

  3. Open the dome shutter, then open the telescope mirror covers.

  4. Open any field stops to ensure light can reach the detector.

  5. Tell the telescope to begin tracking Earth’s rotation. Then, move to a bright star and ensure the telescope is pointing where it thinks it is.

  6. Observe!

  7. Perform 1–5 in reverse to shut down.

It was after 2am by the time we had ironed out any kinks in the procedures and gained confidence in operating the telescopes, so with an unplanned half-night of observing under our belts, we went to bed eagerly anticipating our full weekend of observing ahead. Or, at least, I was – I’ve come to really enjoy staying up all night in the peaceful company of other astronomers and with the ability to go outside and see incredible night skies whenever I want. Maybe I’m crazy, or maybe I’m just meant to be an astronomer. There’s nothing like it!


Friday, May 12th — Monday, May 15th

Hooray, it was finally observing weekend! Granted, we had literally all of Friday to get through first, and maybe I was the only one actually excited about staying up all night to operate a multi-million-dollar instrument, but I think the students were eager as well….at the very least to operate said instruments. After submitting final drafts of their observing proposals and a lecture from me, and after arming ourselves with snacks and coffee, we were ready for our first full night of observing!

We watched sunset, as per usual, and then dispersed to our selected telescopes – I was again in charge of the smaller 1.3m telescope, while the majority of the students opted to use the 2.4m. Aside from being bigger, the 2.4m had different instruments installed that would perform spectroscopy (essentially decomposing all of the light from a source into the amount of light per wavelength), which most of the students’ projects required. This all meant that my job was actually pretty easy! Things went smoothly the whole night, at least at the 1.3m, and I was glad that the first observing experience (ever, for some of the students) went so well!

We wrapped up around 5:30am (I know, crazy), and then slept until the next afternoon. I always feel extremely lazy when observing because I wake up at 2pm or later, even though I stay up until 5:30 or 6am…I’m a night owl for sure, but definitely not nocturnal! Anyway, Saturday afternoon was our mock Telescope Allocation Committee (TAC)…even though we had observed already…oh well, the schedule can always be adjusted! The purpose of the TAC is to evaluate all observing proposals submitted, discuss strengths and weaknesses along with the impact of each, and then give each proposal an overall score. In our class, the top-ranked proposals then got the amount of time at the time of night they requested, while the lower-ranked proposals did not get all of the time they asked for (in the real world, the bottom-ranked proposals don’t get any time at all, if the telescope gets filled up!). I was incredibly impressed with the level of the discussions by the students about each proposal – Sally even said that it was at the level of a real TAC! Our observing schedule was modified slightly based on the evaluations of our mock TAC, and then it was nap time.

Saturday night went pretty much exactly how Friday went – gorgeous sunset, smooth observing, watched a couple of movies (animated Pixar films, obviously!), and wrapped up around 6am. After waking up in the mid-afternoon on Sunday, I decided it was about time I explored the summit a bit, so I took my book and set off to find the perfect secluded reading spot. And oh, did I find it! Look at this view! I definitely went back here several times during the month.

Panoramic view from my reading spot on Kitt Peak. The McGrath solar telescope is on the left, while the peak on the right is known as “Elder Brother” to the Tohono O’odham people.

Sunday night was much more of the same, and again we slept until mid-afternoon on Monday. I was so glad our observing runs went so incredibly smoothly! That all too often seems not to be the case, whether it’s because of some technical failure, a software error, or just Mother Nature. After a lecture and dinner, we all had Monday night off and were able to finally try to adjust back to normal sleeping hours. This is actually starting to become second nature to me…every time I go observing, it seems like I adjust to the opposite schedule even faster than the last time.


And I think I’ll wrap this post up here. I hope you’re enjoying reading about my Kitt Peak adventure so far! I’ll be back soon with the next post in this series, in which we actually get to leave the mountain after 10 straight days on the summit. Though to be honest, I was quite happy to return to 6750 feet after only a short time in the desert heat…

Until my next post, friends!