By Cameron Delfin

If you asked Joachim Moeyens what an astronomer does, he wouldn’t tell you that it’s looking through a telescope.

For him, it’s developing software to understand what’s going on in the cosmos.

“I can count on one hand the number of times that I’ve actually looked through a telescope,” said Moeyens.

But that doesn’t mean his work isn’t crucial to important discoveries in space.

As a research software engineer at DiRAC, Moeyens’ work contributes to asteroid discoveries in the universe. He’s created an algorithm that innovates the way asteroids are discovered, enabling observations from data sets intended for other uses. According to Moeyens, he will use this algorithm to discover asteroids from public data generated by the Rubin Observatory in Chile.

Additionally, his work has the potential to discover dangerous asteroids that might hit the Earth. An improved version of his algorithm could help the Rubin Observatory discover more potentially hazardous asteroids than it otherwise would be able to.

“We’re leaving less of the population undiscovered that might actually have a devastating effect if they were going to hit the Earth,” said Moeyens.

During his undergraduate study at the University of Washington from 2010 to 2015, Moeyens completed a research project with Željko Ivezić, Rubin Observatory director. They continued to work together, with Ivezić encouraging Moeyens to apply to graduate school. There, he began working on asteroid science with Mario Jurić, DiRAC director.

“I feel fortunate that I came here to the University of Washington because I don’t think I would’ve had the opportunities that I’ve had had I not picked here,” said Moeyens.

Moeyens initially hoped to become an aerospace engineer, but his studies led him to applied physics. He dove into astronomy when a friend suggested they take an astronomy elective together. With that, he’s found a way to combine his coding skills with a field adjacent to aerospace engineering, discovering that science and technology are interlinked.

“To do good science, you need to write good software. To do good software, you also have to have … good science. I really like that balance,” said Moeyens.

The connection between software and science resonates with Alec Koumjian, Head of Software Engineering at the B612 Foundation, an organization dedicated to protecting Earth from devastating asteroid impacts. DiRAC and the B612 Foundation work together to find and track asteroids.

“The software allows for computation and the computation allows for exploring many different possibilities,” said Koumjian. “… you use the science to restrict how you interpret those results.”

At DiRAC, Moeyens works with the Rubin Observatory to help paint a picture of what’s in the sky by identifying and tracking asteroids. When the Legacy Survey of Space and Time (LSST) kicks off at Rubin next year, researchers will have another resource to discover asteroids.

“It’s really about mapping what’s out there. It’s understanding our cosmic neighborhood,” said Moeyens.

Astronomers would traditionally discover asteroids by taking two images of the sky in one night and tracking the movement of light sources, according to Moeyens. Between the two images, stars wouldn’t move, but asteroids would.

Using those images, astronomers developed models to observe and predict the motion of asteroids. Those pairs of observations between images are called tracklets.

Moeyens’ Tracklet-less Heliocentric Orbit Recovery (THOR) algorithm enables asteroid discovery without the use of tracklets. THOR can link single observations from different nights rather than relying on tracklet pairs of observations in a single night.

According to Moeyens, THOR gives telescopes more freedom in how they observe the sky as the algorithm doesn’t require telescopes to follow a specific path to make tracklets. Since THOR’s method in capturing data is flexible, more datasets can be used to discover asteroids. And, THOR can make discoveries across different nights from different telescopes.

These insights enable asteroid impact prevention. However, the most difficult part of impact prevention isn’t intercepting asteroids. Instead, it’s discovering them, according to Former NASA Astronaut Ed Lu.

“That’s 99 percent of the battle,” said Lu.

Lu is the co-founder and executive director of the B612 Foundation. According to Lu, shifting the course of an asteroid so that it does not hit the Earth requires changing its velocity by about one millimeter per second. 

This process has been proven possible by NASA. In 2022, they successfully sent a small spacecraft to strike an asteroid, according to the organization.

“Deflecting an asteroid means tiny nudges,” said Lu. “It’s really easy to deflect asteroids.”

On the flip side, that means that researchers have to be accurate to that strict margin in order to identify asteroids that might strike the Earth.

“The hard part is actually knowing that there’s an asteroid out there,” said Lu.

In the future, Moeyens says that he would like to take the discoveries that Rubin makes and use them to further enhance THOR. According to Moeyens, this would enable THOR to be used with different populations of asteroids or for tracking satellites.

No matter the challenge, Moeyens is up for it, using his trusty computer to get the job done – not a telescope.

“I like solving problems,” said Moeyens. “As long as I can write some software to help accomplish it – that would make me happy.”

By Cassie Diamond

Even by his own account, Ari Heinze didn’t have the most promising start to a career in astronomy.

When Heinze was young, his grandfather, a geophysicist, brought over a telescope for him to try for the first time. Heinze’s grandfather set up the telescope so that it was directly pointed at the moon and invited his grandson to take a peek.

Heinze put his eye up to the lens and immediately reeled back in shock at the sight of the glaringly bright surface of the moon, he said.

“All I could see was white,” a young Heinze said to his grandfather.

Heinze eventually learned how to use the telescope properly and let his eyes adjust to view the dazzling cosmos through its lens. 

And what he saw stuck with him, he said.

“I think it was almost a spiritual experience for me, seeing the stars out there when I was very young,” Heinze said. “I felt very close to God.”

This deep fascination with space would lead Heinze to find his professional calling in astronomy.

While Heinze’s astronomy work at first focused on brown dwarfs, he eventually shifted his main area of study to asteroids. In particular, he worked on the ATLAS Project in Hawaii from 2015 to 2021, which is an early warning system designed to detect objects, such as asteroids, that could hit Earth.

Heinze’s study of asteroids led to his current job as a research scientist in UW’s Department of Astronomy and his work on the Vera C. Rubin Observatory, a telescope in Chile that will survey various areas of the universe.

The capabilities of Rubin’s telescope will allow it to capture images with a very large field of view and detect faint objects, according to the Rubin Observatory’s website. This will help astronomers identify subtle changes in the night sky and potentially make new discoveries about our universe.

Heinze’s main role on the Rubin Observatory project, which begins operations in 2025, will be to use software that analyzes these images and determine if objects seen moving through space at different points in time may be unknown asteroids.

One thing Heinze said he specifically hopes his work on Rubin will allow him to study is asteroid collisional families. These families form after a large asteroid collides with another object, causing it to break apart into smaller asteroids that all share similar characteristics such as composition, orbit, and color, he said.

Once Rubin has been running long enough to discover new asteroids located in the asteroid belt, Heinze said he predicts they will also discover many new collisional families as well.

However, Heinze won’t be in any rush to make definitive scientific conclusions based on the images taken by Rubin once they start coming in.

“What I plan to do is sort of relax and enjoy the cool images that come in, and not push really hard on jumping in and getting a science result out first, because the problem you get with the science result you get out first is that it’s often wrong,”  Heinze said.

Heinze said that he hopes this mindfulness will help rebuild trust in science within wider American society.

“People do not trust science as much as they used to,” Heinze said. “And there’s no quick fix for that. The only way to earn trust is by being right reliably a bunch of times for decades, and not being wrong very much. So, that’s a way that I hope my work [and] Rubin in general will contribute to a recovery of trust.”

Ian Sullivan, a senior research scientist in UW’s Department of Astronomy who supervises Heinze’s work on the Rubin Observatory, said that the type of thorough, systematic approach Heinze brings to his work is part of what makes him such a great astronomer.

“[Ari] will focus on a project and work through all of the details and test extensively with simulations,” Sullivan said. “And with that he will methodically work through a problem, and, once he has come to a conclusion, [he can] be very confident that it is well tested and well thought through.”

While the astronomy work Heinze does as part of his career is important to him, he doesn’t want it to prevent him from being with his family. In this way, he said he feels a connection with astronomer Vera C. Rubin, the namesake of the Rubin Observatory.

Rubin, who had four children, deliberately chose to focus on areas of astronomy that no one else was studying in part so that she could spend more time with her family, according to Heinze.

“I have tried to do something similar,” Heinze said. “I love astronomy, I work hard, but I’m not willing to have it consume my life.”

Jane Heinze, Ari Heinze’s wife who has homeschooled their five children, said she admires her husband’s family focus. She described how he will even take the time to explain complex scientific concepts to their children using a whiteboard in their house.

“There’s diagrams of a lens and showing how the light bends through the lens, because we were having a conversation about how do lenses work, and, so, he’s like, ‘Let me just draw it’ and explains it to them,” Heinze’s wife said.

Ari Heinze also has a knack for building unusual devices in his spare time, which often involves  his family, his wife said. 

For instance, he once employed the help of his oldest son to help build a swing connected between four trees in a square formation, allowing it to swing in a giant circle. Influenced by experiences like these, Heinze’s son has also taken on his own personal projects, such as building a treehouse.

“I really enjoy making things work, and I think that’s part of what I enjoy in astronomy as well,” Heinze said. “Because so much of what I do is programming, and I really enjoy making a program work — seeing it calculate the right thing [and] process an image in the right way.”

Although it may be difficult at times, Heinze has found his own way of balancing his passions for both astronomy and his family. Instead of viewing this balance as a hindrance, however, he sees it as an opportunity.

“I know there are things I can’t pull off that other people without families could,” Heinze said. “I think it’s more fun to deliberately avoid areas where the competition is most intense, and it’s more likely [you’ll] be able to discover something really interesting.”

By Dany Villarreal Martinez

For the next decade Meredith L. Rawls, a UW Research Scientist, will work with the largest astronomical digital camera at the NSF-DOE Vera C. Rubin Observatory in Chile, where she will find ways to automate image analysis.

When Rawls is not pipelining photons into images of our vast space, she is looking to our orbiting friends: satellites. 

Satellite constellations, as Rawls describes them, are low orbit satellites that show up in pictures taken of our night sky. This can be misleading for astronomers like her when identifying objects in the sky. What might have been a monumental discovery of a new star, comet, or any other phenomena left to be explored, might just be a bright satellite racing around the Earth. 

Private companies such as SpaceX launch a mass amount of satellites each year for faster and widespread connections to the internet, according to Rawls. In 2019, there were about 2000 operational satellites, and now, in 2025, there will be over 11000.

“It’s kind of like this new space race situation,” Rawls said. “The issue is it’s a bit of an unregulated Wild West because there are not a lot of laws that apply to orbital space.” 

While drawing country boundaries in space is not realistic, part of Rawls’ work advocates for private companies to ensure their satellites will not interfere with astronomical work. 

“Rawls is one of the absolute leading voices in raising concern for satellites at Rubin Observatory,” James Davenport, a UW Professor of Astronomy and long-time friend of Rawls, said. 

Rawls is a co-leader of SatHub, which wishes for darker and quieter skies. Rawls’ works on developing data software and tools to share with astronomers around the world. The goal, according to Rawls, is to automate the process of identifying satellites from other objects in space alongside her work with the Rubin Observatory.  

Eric Bellm, a Research Associate Professor and one of Rawls’ supervisors shares how unique, and impressive, it is for Rawls to have direct communication with the Rubin Observatory’s project leadership. 

Rawls’ love for space came early. Born in Michigan, but raised in eastern Washington, Rawls calls herself a “cliche” as she was like every now-astronomer: a kid looking up in wonder at the deep, dark night sky. 

“I had no idea that I would eventually work for an observatory in Chile,” Rawls said, reminiscing about her undergraduate years at Harvey Mudd College, where she was able to visit Chile twice as part of her research project. 

She then completed her postdoctoral fellowship at UW, after graduating with a PhD from New Mexico State University in 2016. 

“I joined the UW team at a time when there weren’t that many of these newfangled types of resources,” Rawls said. “A lot of us were self-taught and had figured out basic data analysis, kind of, on our own.” 

Rawls’ passion and interest for growing her software development skills gained the trust of her supervisors and she was hired as a full-time research scientist.  

“We saw her growing skills and experience,” Bellm said. “Our code bases are large and complicated things with a lot of moving parts, it takes a lot to get familiar with the systems and she was excited to keep moving with that.” 

Davenport said Rawls is a dedicated worker and wonderful teacher, helping students whenever she can. 

“Meredith is a team member who brings a lot of glue,” Bellm said. “She is someone who is present in the team, easy to relate to, and happy to share.” 

By Amelia Kim, UW News Lab

Fifteen years ago, Sarah Greenstreet was a graduate student when she first learned about the Rubin Observatory. Now she’s contributing to the mass discoveries that the observatory is expected to produce.

The Vera C. Rubin Observatory in Chile will provide scientists with detailed images by surveying the sky for 10 years, bringing in information on asteroids, supernovas, and even another possible planet in our solar system, according to Greenstreet.

As the Rubin Observatory gears up for its first light – the first image and viewing of the sky – Greenstreet, an Affiliate Assistant Professor in the Astronomy Department at the University of Washington and Assistant Astronomer at NSF NOIRLab is contributing to the observatory’s preparations as a member of the Rubin Community Science Team and as a Lead for the Rubin Solar System Science Collaboration, both of which are working to prepare scientists for the survey of the sky through data, software tools, and recommendations for the survey. 

With the telescope having one of the largest digital cameras that has ever been built, the telescope will allow scientists to make many new discoveries.

“I’ve been hearing about the Rubin observatory for so long, and I’ve been a part of the Solar System Science collaboration for about five years now as well, that now getting to be a part of the Rubin Project Team has been really exciting,” Greenstreet said.

Beginning her undergraduate studies at Western Washington University in 2003, Greenstreet pursued a Bachelor’s of Science degree in physics.

“Sarah was one of those people that was worth listening to. She wasn’t always the person who was going to be the loudest, but she had amazing things to say and and I really, really enjoyed working with her,” Kristen Larson, a professor that Greenstreet worked on a research project with at WWU, said. 

As Greenstreet went on to pursue her career even further, she attended the University of British Columbia for graduate studies for her masters and PhD in astronomy, discovering that she was interested in orbital dynamics, the change in small bodies and asteroids’ orbits due to the interaction of planets’ gravity, similar to what she is working with currently for the Rubin Observatory.

“It was not a subject I had ever been introduced to before, but there was something about it that I found just simply fascinating… it completely blew my mind, and so I just, I couldn’t, at that point, imagine doing anything else,” Greenstreet said.

Learning about various topics in astronomy and even applying computer programming into her works, Greenstreet was always curious to learn more about the world above the Earth and determined to find answers.

“Sarah showed a lot of ability to adapt and pursue interesting things, and she’s continued to do that all through her career, since she left UBC,” Brett Gladman, Greenstreet’s previous professor and PhD advisor from UBC, said.

Despite having little research experience headed into grad school, she was proactive in finding research and lab opportunities, including working in a biology lab to gain experience and to further her career, according to Maggie Fuqua, Greenstreet’s friend and former roommate at WWU.

“I think she’s wired to be a searcher, and then once she finds something, really head in that direction with a lot of discipline,” Larson said. 

Heading into the year of the first light for the Rubin Observatory, Greenstreet has been working on compiling code tutorials and documentation to analyze expected data, and educational materials to prepare scientists once the observatory is ready.

Greenstreet also studies near earth objects like asteroids and their orbits. 

“The Rubin Observatory has multiple, very different science goals, ranging from inventorying the solar system to studying dark matter. Both the Rubin Project Team and the Science Collaborations have been working together to try to make sure that the cadence in which the telescope is going to be taking pictures of the sky, will be done in a way that will help make sure that each of the astronomy science goals are accomplished,” Greenstreet said.

As the Rubin Observatory starts its Legacy Survey of Space and Time (LSST), the telescope will take pictures every three days of the southern hemisphere sky, according to Greenstreet. She said they expect to discover another five million small bodies, such as comets and asteroids in the solar system.

“The Rubin observatory is going to increase what we’ve been able to find so far over the last 200 plus years of discovery by a factor of five, which is just completely incredible with just how much data we’re going to get,” Greenstreet said.

Greenstreet said she is passionate about making information from the telescope’s discoveries available in ways that the public can understand. 

“Of course, many of the things that we as scientists discover and we talk about, we know all of the little, tiny, ridiculous details about things that we’ve spent a good chunk of our lives trying to be able to understand, but most people don’t understand a lot of the words that we use on a regular basis, so it’s our responsibility to share our knowledge with people in a way they understand” said Greenstreet.

Greenstreet said she is excited to see what data will be produced from the observatory.

“I think we’ve all been collectively holding our breath,” Greenstreet said. “We’re all poised and excited to be able to be doing [this science], and then beginning to share it with each other and with the world as well, I think it’s just an incredibly exciting time.”

By Pei Xu

In the past decade, Pedro Bernardinelli co-discovered the largest comet in modern times, Comet Bernardinelli-Bernstein. Now, he can expand his research in depth on the Outer Solar System, the region beyond Neptune, in The Legacy Survey of Space and Time (LSST) project. 

Rubin Observatory is a new astronomy and astrophysics facility under construction in Chile, funded by the U.S. Science Foundation and Department of Energy, Office of Science. It also has an ongoing collaboration with DiRAC at the University of Washington. The LSST project at the Observatory is anticipated to be in full operation next year and last 10 years.

In the upcoming project at the Rubin Observatory, the LSST project aims to map a specific ecliptic plane in the sky every three days to track the moving objects in the outer Solar System. Throughout this process, LSST is expected to find 30,000 to 40,000 trans-Neptunian objects, located beyond Neptune’s orbit. 

By joining the Rubin Observatory, Bernardinelli said it allows him to enhance his investigation with advanced equipment and technologies, including telescopes, cameras, and extensive observing time for the LSST project. 

“People like planets, and it will basically expand our fuel to the solar system, right?” Bernardinelli said. “So we have a new planet, we have to figure out how to get it, how it’s formed, what it’s made off, and all sorts of things.”

Bernardinelli started studying astronomy as an undergraduate at the University of São Paulo in Brazil, where he was involved in cosmology and scientific research. He later completed his Ph.D. at the University of Pennsylvania in 2015, concentrating on trans-Neptunian objects and the Dark Energy Survey (DES).

Bernardinelli is interested in dealing with data sets that capture observations of newly discovered celestial objects. His research goal in the LSST is to develop effective tools in decoding the data, allowing him to better recognize and interpret their significance, he said. 

“Pedro is meticulous when it comes to both checking his work and checking the conclusions he draws from them which is an absolute must for good impactful science. He is an active member of the DiRAC solar system group, it’s clear that he cares a lot about the underlying science and is truly an expert on trans-Neptunian objects,” said Joachim Moeyens, Research Scientist, who works with Bernardinelli in the lab.

Bernardinelli said he aims to explore statistical questions, such as identifying the moving patterns of trans-Neoptunian objects, which would contribute to the broader understanding of the outer Solar System and its dynamics, as well as deepen people’s knowledge about the origin of the universe, and how planets formed. 

Nonetheless, Bernardinelli faces the challenge in his research of balancing work and life. He is concerned about finding the next discovery in astronomy as a race, the tension between speed and quality. He indicates that numerous unexplored objects need to be analyzed through data points for new insights.

“Since everyone has access to the data, it is possible for other people to get the new finding of the next big thing and do the characterization about it,” Bernardinelli said. “It is a tradeoff between doing things fast and doing things well.”

With significant contributions in the past and the opportunity to explore the universe at the Rubin Observatory, Bernardinelli is looking forward to the next phase of analyzing the trans-Neptunian objects through the LSST project. 

“I went from this small Brazilian project to the big U.S. project to this big worldwide project. So this will be fun,” he said. “I’m very excited for the LSST to start. What surprises await us, what sort of weird, wacky object in the Solar System we’re going to find with the LSST.”