Meet the DAWN-IRES Scholars: Mahitha Ramachandran

Banner photograph by Mahitha Ramachandran of the Cisternerne, a former water reservoir turned underground art space in Frederiksberg, Copenhagen.

Meet the DAWN-IRES Scholars: Mahitha Ramachandran

Mahitha standing in front of the white cliffs at Møns Klint. Photo taken by cohort member Alexander Poulin.

Tell me a little about yourself.  I'm an undergraduate at Yale University going into my senior year, majoring in Astrophysics and South Asian Studies — two very different things, but I think they represent the breadth of my interests well. I did my first year at the University of Pittsburgh before transferring to Yale.

Outside of astronomy I am particularly interested in art and art history, especially in relation to South Asia. I make my own art as well. I weave on a floor loom, make ceramics and jewelry, embroider, and sew, and I'm constantly exploring new mediums. I also play piano and have done some music production. This past year, I turned astronomical images from the James Webb Space Telescope into music using sonification techniques as part of a multimedia installation project.

How did you get interested in astronomy?  I was always curious about space growing up. I think it comes naturally to children to look up and wonder. In high school, I had a really amazing physics teacher who made me love it and, just as importantly, made me believe I could do it. Around the same time, I started volunteering at the Carnegie Science Center's Buhl Planetarium in Pittsburgh, where I got to teach people of all different ages and knowledge levels about astronomy. Teaching it in that kind of environment made me love it more. I think there's something inspiring about the natural fascination and awe that astronomy strikes in everyone.

I see astronomy, the scientific pursuit, as just one way to understand the universe and our place in it — to connect to the people who came before us and those who will come after, and to make sense of the simultaneous vastness and minuteness of our existence. Those big questions have always really consumed me. When I was around 16 to 18 years old and being asked to figure out what I wanted to do with my life, astronomy felt like a way to swim rather than drown in those questions.

I love that astronomy tugs you in every direction; we think about timescales on the order of billions of years right beside events you'll miss if you blink. I'm also fascinated that we look into the past and try to decipher it, or even use it to predict the future. In that sense, I think astronomers are historians and archaeologists, which resonates with my other interests.

What is your favorite part about Copenhagen? DAWN?  It is genuinely hard to pick a favorite thing about Copenhagen. I love the transportation infrastructure. I’m a huge public transit advocate, and I use it every day here. I also love the many green spaces integrated into the city.

But I think my favorite thing is the arts scene, and the genuine appreciation and respect for art that seems to be woven into the culture of the city. I've been to countless museums, galleries, exhibitions, and performances and still have a never-ending list of more to go to. But it's more than just the major institutions — the city itself is filled with art and design, whether in the fashion, the street art, or the architecture. It feels like life here is understood to be entangled with art, and there's a real investment in that entanglement.

At DAWN, my favorite thing is the sense of community and collaboration. The rigid hierarchy that you find in a lot of academic spaces doesn't seem to really exist here. People want to discuss, share, and spend time together, and they genuinely value each other. I think that's a really ideal environment for anyone, but especially for an undergraduate student.

What motivated you to apply to an international summer research program?  Growing up, my family moved a lot. I graduated high school in Pittsburgh but lived in four other states before Pennsylvania. Moving that frequently was hard in the moment, but in hindsight it shaped me in a lot of good ways. I developed a strong sense of self, because every time you start over you have to look inward and figure out what you actually want, what kinds of friends, what kinds of activities. The fear of going somewhere new disappeared, which made me adventurous.

I think that's a big reason I felt comfortable transferring universities, and a big reason I was drawn to an international program. I had never lived outside the United States for a significant amount of time, so that was naturally an exciting prospect. I love to explore and meet new kinds of people, and I think experiences like this expand my understanding of both the world and myself.

Can you tell me about your summer research project?  I'm working with Joris Witstok and Alex Cameron on exploring a new data release from JADES, a deep survey conducted by JWST that has collected imaging and spectroscopy of galaxies in the early universe — from when the universe was roughly half a billion to about 2 billion years old.

Specifically, I'm investigating how we can use emission line diagnostics to better understand the conditions inside those early galaxies. When galaxies form stars, the radiation from those stars excites the surrounding gas, causing it to emit light at specific wavelengths, which we can see in a spectrum. The ratios between different emission lines can tell us about galaxy properties like their stellar mass, at what rate they are forming stars, and the chemical composition of their gas.

These kinds of diagnostics have been well studied in nearby galaxies, but we've previously been limited to relatively small samples of distant galaxies from the early universe. Now, with this new JADES data release, we have high-quality spectra for over a thousand early galaxies at once, which opens the door to mapping out broader trends and comparing what we observe to predictions from theoretical models. I'm working with both well-known strong emission lines and some less-studied diagnostics. The goal is to build a better empirical picture of how these line ratios relate to other galaxy properties at cosmic dawn.

What skills or knowledge have you been working on developing so far this summer?  I've done research in previous summers, but I'd never worked with high-redshift galaxies before, so a lot of the early work was building up knowledge about the early universe and the new considerations that come with it.

More broadly, I'm working on developing scientific independence — learning to take the research in directions I'm interested in, rather than just completing a set of steps laid out by my advisors. I'm lucky that my mentors have been really encouraging of that, allowing me to explore beyond their suggestions. I won't pretend I'm there yet; it takes a lot of trust in yourself, and that's genuinely hard. But I think it's something I'll gradually get more comfortable with, and it feels like an important part of growing as a scientist.

What Danish word or phrase have you picked up that you now use constantly?  Before the summer started, I went on an Internet hunt for things happening in Denmark during the summer, and I found out about Roskilde Festival — a huge, completely nonprofit, volunteer-run music festival about 30 minutes by train from Copenhagen. If you volunteer at the festival, you get in for free, so I emailed every volunteer group I could find and finally landed a spot selling festival train tickets at Roskilde Station.

The festival was a couple weeks ago, and during my volunteer shifts I picked up the numbers in Danish very quickly as people told me how many tickets they wanted: en billet, to billetter, tre billetter — one ticket, two tickets, three tickets. I also made some great Danish friends at the festival who taught me skål (cheers), though they told me I pronounce it in a very Swedish way. It was an exhausting week as I was going after work and camping there on weekends, but it was completely worth it.

Meet the DAWN-IRES Scholars: Andrés Luengo

Andrés along the famous tree-lined path at Assistens Cemetery in Copenhagen, the resting place of Hans Christian Andersen, Niels Bohr, and other Danish luminaries.

Tell me a little about yourself:  I was born in Venezuela and moved to the United States when I was 10 years old, settling in Weston, Florida, near Fort Lauderdale. I did my middle and high school years there before heading to Yale University, where I study physics and computer science. All of my research, though, is in the astronomy department, where I work with Prof. Earl Bellinger in the Yale Astro ML group.  We apply machine learning to asteroseismology, the study of stellar interiors through the oscillations stars make, a bit like using seismic waves to probe Earth's interior.

I originally applied to Yale as an astrophysics student, then switched to a physics major between freshman and sophomore year when I wasn't sure what I wanted to commit to.   Though, at this point, I've come around and will probably end up in astronomy anyway. One thing I didn't expect from Yale was how much the liberal arts side of it would shape how I think. I originally wanted to go somewhere more technical, like MIT or Georgia Tech, and thought I had no business taking non-STEM classes. Having them essentially required has turned out to be one of the best things about my time there.

How did you get interested in astronomy?  I wanted to be an astronaut when I was little (pretty standard) and that interest just kind of carried through as I grew up. I watched a lot of pop science content about astronomy, especially the YouTube channel Kurzgesagt, which made really entertaining videos about big ideas in physics and space. I also knew early on that I liked physics and computer science from my classes, so astronomy felt like the natural intersection of all of it.

What is your favorite part about Copenhagen? DAWN?  The bike infrastructure here is genuinely remarkable.  I’ve been riding around a lot, and the whole city just makes it easy. I grew up going to Universal Studios, so I'm used to amusement parks being hectic and loud, but even Tivoli felt completely different, more like a beautifully manicured garden than a theme park. Copenhagen just seems to have its priorities in the right place when it comes to parks and public space. It feels like a very healthy city to live in.

At DAWN, I love how many opportunities there are to interact with everyone. The communal lunch, where the whole group grabs food and sits together at a big long table, is something I'd never experienced at quite that scale before. And the Cake Talks, where researchers give informal presentations over cake, have been a great way to get a broad view of the different things people are working on, even when some of it is a bit beyond my level to follow in full detail.

What motivated you to apply to an international summer research program?  I haven't done a lot of travel since starting high school, and this felt like a real opportunity to step outside my comfort zone. Everyone tells you to study abroad, but as a physics major it's hard to make work, so this is my version of it. I've also never been away from family for quite this long, though I can't claim to be a total stranger to big transitions, having moved to a whole new country at age 10.

A JWST image of a galaxy group in GOODS-South seen when the Universe was about 2 billion years old. The three interacting galaxies, nicknamed "The Good, the Bad, and the Ugly" by the research team, include a dormant galaxy, a mysterious compact red object, and a dusty star-forming galaxy. Andrés is working to characterize each one and understand whether their interactions have shaped their very different fates.

Can you tell me about your summer research project?  The project is focused on a really interesting system in GOODS-South, a region of the sky that has been imaged deeply by both the James Webb Space Telescope and the Hubble Space Telescope. What makes this system exciting is that it appears to contain four very different types of galaxies — a star-forming galaxy, a "little red dot" (mysterious compact objects seen in the early universe that have sparked a lot of debate about what they actually are), a dusty star-forming galaxy, and a quiescent (dormant) galaxy — all at roughly the same distance from us, and apparently interacting with each other.

The project has two connected goals. The first is to characterize each of these galaxies individually, figuring out their masses, how quickly they are forming stars, and their histories by modeling these properties from the light we observe. The second goal is to understand the broader environment: we think these galaxies may be part of an overdensity, an early cluster where many galaxies have gravitationally gathered together in the same region of space. If the dormant galaxy has stopped forming stars partly because of its interactions with its neighbors, that could be evidence of "environmental quenching" — the idea that a galaxy's surroundings can play a direct role in shutting down its star formation.

As a side note: while getting set up with the tools early on, I found and fixed a bug in EAzY, a widely used software for estimating galaxy distances from their light. The developer, Gabe Brammer (who is faculty here at DAWN) , added me as a contributor to the project.  I thought that was very generous for a one-line fix, but I appreciated it a lot.

What skills or knowledge have you been working on developing so far this summer?  I feel fairly confident in my technical abilities and the coding side of things. What I'm hoping to develop more is the scientific judgment side by getting better at reading papers and building enough understanding of what I'm doing to be able to pick my own next direction rather than immediately checking in with my advisor every time I finish a step. Those are harder skills to develop, but I think this summer is a good place to start. The workshops have helped. Particularly Will's session on how to read a scientific paper, which was genuinely useful because my advisor has already been sending me papers to get through.

What Danish word or phrase have you picked up that you now use constantly?  Undskyld mig, or “excuse me.” I learned it out of necessity when I first started biking, because I was a little reckless and needed it fairly often. I'd say I've improved since then. I've also been trying to learn Danish on Duolingo so I could at least read grocery store labels — though I have yet to meet a single person in Copenhagen who doesn't speak perfect English, so the practical urgency has been limited.

Meet the DAWN-IRES Scholars: Will Jarvis

Banner photograph by Will Jarvis of globular cluster Messier 13, a massive cluster of several hundred thousand stars that formed more than eleven billion years ago. Will's project aims to one day observe clusters like M13 much closer in time to when they formed.

Will is a DAWN-IRES Senior Scholar, leading professional development workshops while continuing his PhD research.

Tell me a little about yourself. I'm a PhD student in the Department of Astronomy at UMass Amherst, currently transitioning from my first to second year, working with Kate Whitaker. I did my bachelor's at the University of Wisconsin-Madison in astrophysics, where I mostly worked on active galactic nuclei (AGN), the intensely luminous cores of galaxies powered by supermassive black holes, before deciding to try something different for my PhD.

Outside of research, I play drums — I drum for the pep band at UMass and have played in a few bands, including a space rock band called Live from Mars that has two albums out (I write most of our lyrics). I also compete in ballroom dance, mostly international waltz and foxtrot this past semester, plus rumba and cha-cha, and I love lindy hop (a style of swing dance). I write poetry and do astrophotography on the side.

Will and partner Sonia dancing the rumba at the MIT Open Ballroom Dance Competition where they took second place.

I grew up in Wisconsin Dells, the self-proclaimed water park capital of the world, with more water parks per capita than almost anywhere on Earth. My high school job was at a local science museum, where I was the caretaker of a backup Mir space station module (built to launch and replace the actual Mir Space Station in 1991, but abandoned and purchased by a local businessman after the fall of Berlin Wall). So for a few years, it was just the astronauts and me looking after space stations.

How did you get interested in astronomy? I was drawn to aviation and space from a young age. My grandfather flew the P-38 Lightning in World War II, which inspired a love of aviation early on, and visiting my uncle, the chief autopilot engineer at Boeing, for a tour of the manufacturing facility when I was about 8 left a big impression.  I started going to the EAA AirVenture airshow in Oshkosh, Wisconsin, where I met astronaut Kent Rominger in high school, which pushed me further toward science and STEM. Watching Star Trek growing up really sealed my interest in studying space specifically.

My turning point was working with the Pulsar Search Collaboratory (run out of West Virginia University) as a high school senior. I got to use the 100-meter Green Bank Telescope for a week, including being woken in the middle of the night and given half an hour to do whatever I wanted with the telescope. I spent about 24 hours trying to reduce and analyze the data afterward so I could present it in a talk a day and a half later. After that experience, I was hooked.

What is your favorite part about Copenhagen? DAWN? The community at DAWN has been great — the grad students and postdocs are lovely, and everyone is genuinely interested in talking about science and answering questions. I'm in a bit of a unique position since globular clusters aren't something DAWN typically works on. That’s actually opened a lot of doors, since people are curious to learn, and it's let me reconnect with some AGN conversations from my undergrad work too.  A nice full-circle moment!

As for Copenhagen itself, the city is beautiful and biking everywhere makes it easy to get around. The music scene has been a true highlight for me. I've been going to open jams a couple of times a week and have played drums on stage 8 or 9 times since arriving. The jazz scene here is something else entirely.

What motivated you to apply to an international summer research program? I wanted real experience doing science in a different country and culture, and DAWN had the right people to make that worthwhile, with strong faculty and postdocs across the board. I'd always wanted to study abroad as an undergrad but could never make the timing work. I did two REUs in college, in Hawaii and Nantucket, but living in a European country is a different experience than living on a U.S. island. I also already knew DAWN postdoctoral fellow Conor McPartland from a previous REU, so it was nice walking into DAWN with an existing connection, even though our research has diverged since then.

Can you tell me about your summer research project? This summer I'm building one of the first samples of globular clusters at high redshift, looking back across roughly 10 billion years of cosmic time. I'm focused on the most massive clusters from this era, since the smaller ones are too faint to detect with current data. Studying the massive ones tells us how globular clusters formed in the early universe and lets us compare their properties to clusters we see locally today, including how much mass they lose over time. I am focusing on looking at clusters around the most massive host galaxies in the universe, to understand why those galaxies seem to have an excess of clusters, and whether their clusters are unusually massive.

I'm also working with DAWN faculty Johan Fynbo on a machine learning side project to build a training set such that an algorithm can learn to identify globular clusters automatically rather than relying on time-consuming visual inspection. This becomes increasingly important as the James Webb Space Telescope (JWST) produces more deep fields and as upcoming telescopes like the Nancy Grace Roman Space Telescope and Euclid open up much larger areas of sky. At scales such as these, we'll need machine learning to find not just hundreds of globular cluster candidates, but expanding to millions or possibly even billions across the sky.

What skills or knowledge have you been working on developing so far this summer? The biggest skill I’m developing is learning how to use a software called Prospector to do spectral energy distribution modeling of the cluster candidates.  This is a technique where you take JWST imaging across multiple wavelengths, extract the light from each cluster, and model it to estimate physical properties like mass and stellar age. It's a new methodology for me, so it's taken real time to learn.

I've also been developing and leading workshops as a DAWN-IRES senior scholar, which is new territory.  I’ve mentored students individually before, but not designed time-constrained workshops on a range of topics. One I led was on how to read a scientific paper: I wrote a tutorial and then walked students through an actual paper together, discussing strategies for pulling out the information you need efficiently. It seemed especially useful since their research advisors have already started handing them papers to get through.

What Danish word or phrase have you picked up that you now use constantly? Smørrebrød — the classic Danish open sandwich. I can't get enough of it. I spent a week with my cousins recently who showed me how to make several versions; it's traditionally made with rye bread and topped with things like pickled or curried herring, roast beef, or hard-boiled eggs, sometimes mixed, sometimes kept separate. I'm determined to recreate it back home, even if tracking down all the herring varieties might be a challenge — my partner wants to learn to make the rye bread too.