NC State’s College of Sciences is home to faculty who are leading researchers in a wide variety of scientific disciplines. We sat down with Rongmon Bordoloi, an observational astrophysicist who studies how galaxies form and change over time, to explain what astrophysics is and how you can study it, too. 

What Is Astrophysics?

Astrophysics is a branch of science that uses physics to understand how stars, planets, galaxies and the universe itself work. Astrophysicists use the same physical laws that apply here on Earth to figure out what things in space are made of, how they form, how they evolve and how they interact. We use telescopes to observe the universe and use laws of physics to explain these observations.

What Is a Galaxy? How Do Galaxies Form?

You can think of a galaxy as a giant city made up of billions of stars, planets, gas and dust, all held together by gravity. Galaxies form when huge clouds of gas and dust collapse under their own gravity and begin to spin. As they pull in more gas, the clouds grow, form stars and eventually evolve into the large, complex systems we know as galaxies. 

Galaxies come in many shapes and sizes. Nearly all galaxies have a supermassive black hole at their center. Sometimes galaxies come close enough to each other that they collide and merge to form new ones. In fact, the Milky Way — the galaxy we live in — and the neighboring Andromeda galaxy are expected to merge in a few billion years to form a new, giant galaxy.

What Has NASA’s James Webb Space Telescope Discovered Since Its 2021 Launch?

Since its launch, the James Webb Space Telescope has transformed our understanding of the early universe. Out of its many groundbreaking discoveries, three are especially exciting to me. They give us a much clearer picture of how the first galaxies, stars and black holes formed — and how they helped shape the universe we see today. I’m fortunate to be directly involved in two of these discoveries as part of a major James Webb Space Telescope project called the Emission-line Galaxies at the Epoch of Reionization (EIGER) survey, which studies thousands of young galaxies from when the universe was less than 1 billion years old.

1. The James Webb Space Telescope has helped us discover some of the most distant galaxies ever observed, likely formed 280 million years after the Big Bang, with some at redshifts greater than 14. This tells us that their light has been traveling for over 13.5 billion years to reach us!
2. Through EIGER survey data, we’ve discovered over 1,000 galaxies that were already glowing brightly and creating huge, ionized bubbles around themselves when the universe was just 5–6% of its current age. Some of these bubbles are over 2 million light-years wide, showing that galaxies played a major role in making the universe transparent to light. Think of these galaxies as powerful fog lights — shining brightly and clearing their cosmic neighborhoods.
3. EIGER survey data has also led us to discover a population of Little Red Dots, or LRDs, which are tiny, faint red objects that initially appeared to be early galaxies. Follow-up studies revealed that many of them are actually baby quasars, small galaxies with fast-growing supermassive black holes at their centers. These young black holes are rapidly accreting gas and glowing intensely, making them some of the earliest known active galactic nuclei in the universe. 

What Is the Big Bang Theory?

The Big Bang Theory is our best explanation for how the universe began. It tells us that the universe started about 13.8 billion years ago as a very hot, dense point, and has been expanding ever since. It cooled as it expanded, allowing the first atoms to form, then eventually stars, galaxies and everything else we see today.

James Webb Telescope’s Big Bang Theory Discoveries

The James Webb Space Telescope is helping us fill in the gaps between the Big Bang and the rich cosmic structures we observe today. Unlike earlier telescopes, the James Webb Space Telescope can see infrared light, which is perfect for detecting the faint glow from some of the very first galaxies. This capability allows us to study cosmic reionization, one of the least understood phases of the universe’s history. This period refers to the few hundred million years after the Big Bang, when the first stars and galaxies lit up and started to reionize the neutral hydrogen gas that filled the universe. Initially, the hydrogen gas blocked most light and reionization allowed light to start traveling freely.  

What Is Your Favorite Fact About Space?

The most incredible thing about astrophysics is that it gives us context for how we fit into the vastness of the universe. My favorite and most awe-inspiring fact about space is that we are all made of star stuff, to paraphrase astronomer Carl Sagan.

Atoms — which are the building blocks that make up our bodies, the oxygen we breathe, the carbon in our cells and even the silicon in the phone or tablet you’re holding — were all created within stars through nuclear fusion. When those stars exploded at the end of their lives, they scattered atoms across the cosmos. Those star-forged atoms went on to form new stars, planets and eventually life, including us.

What Kind of Space Research Is Happening at NC State?

At NC State, students aren’t just learning about the universe. They’re actively helping to uncover its secrets. My students and I work with data from both the James Webb Space Telescope and the Hubble Space Telescope to study how the earliest galaxies formed and evolved in the early universe, eventually becoming large systems like our very own Milky Way. 

In another exciting area of our research, we use gravitational lensing to observe very young galaxies in far more detail than we otherwise could. The natural phenomenon results in massive objects in space, like galaxy clusters, bending space-time and magnifying the light from more distant galaxies behind them. Gravitationally lensed galaxies appear stretched and brightened, giving us a “cosmic zoom lens.” It’s like boosting your telescope with a natural magnifying glass in space.

Why Is NC State a Good Place to Study Astrophysics?

If you’re curious about the universe and want to be part of a growing, supportive and research-active community, NC State is a fantastic place to start that journey. Our students are part of a close-knit physics and astronomy community while having access to all the resources of a major research university. They have many opportunities to get involved in hands-on research in both observational and theoretical astrophysics. Projects include:

• Studying how galaxies evolve from the early universe to today.
• Simulating stars, supernovae and their remnants. 
• Studying gravitational waves like stellar explosions and black hole mergers.
• Exploring accretion processes around compact objects like neutron stars and black holes.
• Modeling neutrinos and nucleosynthesis in stellar environments. 

We also emphasize mentorship and career preparation, helping students find internships, research placements and pathways into graduate school or careers in STEM fields. Plus, our location within the Research Triangle gives students access to one of the most vibrant science and tech hubs in the country.

How Do You Become an Astrophysicist?

To become an astrophysicist, you need a strong background in physics and math, usually in the form of a degree in physics, astronomy or a related field. Most aspiring astrophysicists go on to earn a Ph.D., specializing in areas like galaxies, black holes or cosmology. You can get involved early by joining undergraduate research projects or summer schools. After that, it’s all about research, coding, data analysis — and staying curious about how the universe works.

How Do You Become an Astronaut?

To become an astronaut, you typically need a strong STEM background, such as a degree in engineering, science or medicine, plus relevant professional experience and excellent physical fitness. NASA accepts both civilian and military applicants.

Selection is extremely competitive, but not impossible. For instance, one of NC State’s own alumni, Christina Koch, earned dual degrees in electrical engineering and physics, worked on space‑science instruments at NASA Goddard Space Flight Center, and then spent years in Antarctica before being selected as a NASA astronaut in 2013.