How did the universe come to be? What did the first stars look like? Where do planetary systems come from and how do they evolve? Is Earth unique? Are we alone in the universe? These questions and more were on the mind of NASA senior astrophysicist John C. Mather in April 2022, as he and some fifty other astrophysicists, astronomers, and engineers gathered in the mission control room at the Space Telescope Science Institute in Baltimore for a day of reckoning. After a thirty-five-year journey that had included technical adversity, numerous threatened cancellations of the project, and a nearly four-month wait since the December 25, 2021, launch, the $10 billion James Webb Space Telescope (Webb) was about to reveal how well it did—or did not—work.
With a 6.5-meter diameter, Webb is significantly larger than the Hubble Space Telescope. On that April day, Webb was focused on a single star surrounded by total darkness in the Carina-Sagittarius Arm of the Milky Way galaxy, approximately 8,500 light years from Earth. Mather and others gasped as countless lights sprang up amid the darkness. “My God, there were just galaxies everywhere,” Mather says. Although the public would have to wait two more months for NASA to unveil the first images from Webb, Mather and his team now knew that the telescope worked and was already altering the contours of our knowledge of the universe—answering some questions while raising ones previously unimagined.
Webb is the most sophisticated astronomical instrument in history. It is a hundred times more powerful than Hubble and boasts technological advances such as a deployable tennis court–size sunshield and a folding segmented mirror. The telescope is able to capture infrared light from 13.6 billion years ago, enabling views of the early universe almost 200 million years after the Big Bang. Early images showing that galaxies started forming faster and earlier than expected have surprised scientists, and the data the telescope will collect over the next decade is likely to completely transform our understanding of the cosmos. Mather’s own passion for cosmology began with his earliest educational experiences. He believes that education and the research that takes place at colleges and universities play a critical role in scientific achievements such as Webb.
Raised on a Rutgers University agricultural research farm where his father studied animal husbandry, Mather says his interest in science dates to age six. He began to wonder about the mechanics and origins of the natural world as he hunted for fossils and examined geographic formations on the farm. As an elementary school student, he built one-tube radios, assembled a small refractor telescope, and constructed a robot from a vacuum cleaner. Although the robot never worked, Mather became hooked on innovation and trying to solve hard problems. While still in high school, he attended summer programs in math at Assumption College in Massachusetts and in physics at Cornell University in New York. These higher-education opportunities helped focus his attention on astronomy, cosmology, and astrophysics.
Mather went on to attend Swarthmore College in Pennsylvania and then the University of California, Berkeley, for graduate school in physics. At Berkeley, Mather became interested in colossal magnetoresistance (CMR)—the heat produced at the beginning of time. Since then, Mather’s career has focused on infrared astronomy and cosmology.
In 2007, Mather and cosmologist George F. Smoot won the Nobel Prize in Physics. Mather used his prize money to create a scholarship program that provides graduate student fellowships and travel grants for NASA and Goddard Space Flight Center interns. He believes that education is key to the future vitality of the United States. “A well-rounded education keeps us from being bored and boring,” Mather says. “We must keep learning.” At age seventy-seven, Mather remains intensely curious about where space exploration will take us next. “I’m excited to see the places we’ll go,” he says.
What’s been most compelling so far in the deployment and early science returns of the James Webb Space Telescope program?
The 2021 Christmas Day launch was exciting, although I was calm that day. After working for twenty-six-plus years on a project, you can’t be nervous every minute. Still, it was surreal. I later witnessed the telescope come into focus in April 2022. We were in a small conference room, and the projector came up with a perfect image of stars and galaxies that humans had never seen before. Since then, we’ve seen galaxies collide and merge, a black hole close-up, and the debris from an exploding star. It was worth the wait.
How is Webb changing our understanding of the universe?
We are trying to understand where we came from. We have so many questions: What was the process that led from the earliest moments of the expanding universe to the formation of stars, galaxies, and black holes? What are dark matter and dark energy doing? How do stars and planets grow inside clouds of gas and dust? Do other planets exist that, like ours, are habitable? Are there other places in the universe with earthlike life? It’s a big set of questions, and we never know when we’re going to get a surprise.
Space exploration has charismatic appeal. How do projects like Webb inspire new generations of scientists and generate public enthusiasm for science?
The photos from the telescope grab people’s attention, and then they want to understand what’s going on in the universe. I had a similar experience as a young person when I visited the American Museum of Natural History in New York City and saw the dinosaur bones and the Hayden Planetarium show. I wanted to know more!
More students will want to go into science and engineering because Webb has activated their imaginations. Many of them will want to be astronomers—we don’t need that many professional astronomers, but these students will spread out to the rest of the sciences and become doctors, engineers, and chemists. They’ll solve problems right here on Earth.
How can space exploration help generate support for space science and science programs at colleges and universities?
In the early 2000s, a popular TV sitcom called The Big Bang Theory led to a surge in the number of students who wanted to study physics. According to the New York Times, the number of physics majors in American colleges and universities doubled. We know that media coverage and public impressions of science can change our educational system without anyone legislating it or planning it. Popular projects like Webb excite people and drive demand for more and better science programs.
How can we get today’s K–12 students more invested in and excited about studying math and science?
Students need to directly experience the power of discovery, and we must do everything we can to encourage their curiosity. A lot of schools have lost their science students because they give their pupils a dry book and say, “Learn this, and then we’ll test you.” That takes all the fun out of it. If you handed athletes a book about football and told them to study it and then take a test, they would not want to play football. People learn best by doing.
If a twenty-one-year-old asked you why they should go into physics or astrophysics, what would you answer?
I would say, “Go into physics or astrophysics if you’re really curious about tricky, hard problems. If you want to think deeply and tackle difficult questions, then this is the place for you.” Of course, that also applies to biology, chemistry, math, and every other science. There are fascinating problems to work on and puzzles to solve. The way I picture it is that scientists are working to fill out the rest of the crossword puzzle of the universe—and the answers will have unexpected applications everywhere. For example, the person who figured out how to measure the mirrors of the Webb Telescope then went on to invent a tool that ophthalmologists use every day to measure patients’ eyes.
As a high school student, you attended two summer programs on college campuses. Based on your experience, how does bringing high school students to college campuses encourage kids to go into math and science?
Two important things happen. One, you meet people who are interested in the same things you’re interested in—that helps you realize that you’re not the only one and that science is fun. You also make friends who may last a lifetime and help you along your path. Second, if you do well at a summer program, it gives you the courage to continue. Not only is it fun, but you realize that you can do this. I felt that way after I spent a summer at Cornell University studying physics.
For college and university students, what’s the value of studying at a research institution?
I have observed that when young people participate in a university research program or project, it makes a huge difference to their motivation and their abilities. Knowing what scientists are up to and getting to be part of their research is a profoundly different experience from just reading and learning things from a book. When you wake up in the middle of the night thinking about your research project, it’s different from worrying about a test and getting the right answers. Research is very attractive, and people love doing it. It also gives students a reason to learn math and statistics, because they need to apply them to research.
How does coupling scientific training with a liberal education—an educational approach that promotes thinking critically, developing curiosity, and using the imagination—help when pursuing scientific questions?
All the qualities of a liberal education are also hallmarks of scientific research, so I view the two as deeply related. Both ask students to investigate similar questions: How do you argue a point? What’s the evidence for my idea, and what’s the evidence against it? What do I need to take into account to explore this topic? A liberal education also teaches skills, such as writing, that you need to succeed as a scientist.
Should science majors study poetry and the fine arts?
They don’t have to, but they will miss some amazing things if they don’t. I didn’t study poetry or the fine arts, and I almost failed my art history class in college. So, this stuff wasn’t easy for me—but I still think it’s interesting and important. I think all students should take the opportunity to learn about these topics while they’re in school.
The majority of science and mathematics graduate students in the US are foreign-born. There’s been a decline in international student applications to those programs in recent years, and the pandemic accelerated that trend. How is this affecting scientific education and research in the US?
Scientists are very mobile, and the demand for good scientists is high. Prospective graduate students and emerging scientists can usually choose where to go. So, the question is, Why do some individuals no longer see our country as the best place to choose? Is it that we’ve changed our educational programs, or is it other factors?
It seems to be mostly the latter. This country has become much more hostile to immigrants. As a foreign-born student, why would you want to deal with that and with the indignities of our immigration system every time you wanted to travel? That’s a serious issue, and it’s been going on for a while. Then COVID-19 made things even trickier. If we want the most talented people to choose to come here and then decide to stay, we need to make things easier for them and create a friendlier environment. Why would talented foreigners want to come here and work with us if we are hostile to them?
Women and people of color currently represent 70 percent of college students but make up less than 45 percent of STEM degree holders, and that gap widens dramatically with the physical sciences. For example, in 2021, less than 4 percent of all undergraduate physics degrees awarded by US institutions went to Black men and women. How can we diversify the STEM pipeline?
That’s a huge question, and many organizations are working on it. We need to actively encourage our best young people to choose these fields and ask them to join us in our research. Unfortunately, there are a lot of places in the US where young kids want to study the physical sciences, but there aren’t enough local resources. If a school does not have sufficient computers, books, paper, and pencils, then students cannot get very far. Salaries for K–12 teachers are also a serious issue. We have nationwide problems with this because of the way we fund our schools.
I was on the National Academies for Sciences’ (NAS) committee that wrote a framework proposing a new approach for K–12 science education. It was the NAS’s most downloaded document of all time. People care deeply about science education. We’re making progress, but it’s darn slow due to larger societal issues.
What advice would you give instructors at colleges and universities who are teaching the next generation of space scientists?
Give your students something real to work on so they can see why they need to study different topics. Ask them to make a tough calculation for a project, and then they will understand why they need to know calculus. Also, every student is not equally prepared for college—create opportunities for people to catch up. Instructors need to realize it’s too easy to mistake preparation for talent.
Faculty also need to change their mindset. In physics and astrophysics, there’s often the idea that certain people are simply born really smart. That’s intimidating. If an individual works hard at something for long enough, you can’t tell the difference between intellectual passion and natural talent. Being smart doesn’t mean you’ll automatically ask the right questions or work on suitable topics.
Similarly, the idea that some students are more talented, and therefore they are the only ones we should help, is wrong.
Circling back to where we began our conversation, Webb will be observing space for another twenty-plus years. What does the future hold for the work of Webb and other NASA telescopes?
We’ll have the opportunity to examine more of the sky, and we’ll respond to new discoveries as we make them. We’ll fly the Nancy Grace Roman Space Telescope, named after our first NASA chief of astronomy. It’s designed to examine dark energy and dark matter and to search for and image exoplanets—planets beyond our solar system. We’ll look at the environments on these planets and whether they have water. And really, who knows where we’ll go or where we’ll end up? Whole worlds are waiting to be discovered.
Lead photograph: John C. Mather, senior astrophysicist (NASA/Taylor Mickal)