Maine native among team that found planet engulfed by its star
May 5—Morgan MacLeod was an eager sixth-grader growing up on Orr's Island when he first witnessed the grandeur of the universe.
What he saw back then would ignite an interest in astronomy that led him to become an astrophysicist and assist in the recent discovery of a planet being swallowed by its star, a first-time find announced this week in the journal Nature.
MacLeod designed the computer model of the planet's demise, which serves as a blueprint for how the Sun could consume the Earth in 5 billion years. His introduction to the wonders of the solar system when he was 11 years old was more humble but no less impressive.
He was standing in the backyard, peering through his father's birding telescope, when he spotted Jupiter on the eastern horizon.
He had studied the planet in depth for a science project at the Harpswell Community School. Earlier that day, when his class visited the Southworth Planetarium at the University of Southern Maine, he learned how to find Jupiter in the evening sky.
There it was, suspended between treetops, above a neighbor's house. He recognized its orange stripes and the four dots that are Jupiter's largest moons.
"It was this incredible moment when I realized astronomy is real," said MacLeod, "and I've been really, really excited about it ever since."
Now 35, MacLeod is a post-doctoral research fellow at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, a collaboration tasked with answering the greatest questions about the universe.
He is one of 26 scientists from several research facilities, including the Massachusetts Institute of Technology and Johns Hopkins University, who published an article on May 3 about their planet-swallowing discovery that began in 2020.
That's when astronomers first saw a burst of light indicating that a planet had connected with a star about 15,000 light-years away in the Milky Way's galactic disk. Neither the planet nor the star has a name, but their interaction is called ZTF SLRN-2020, a short-lived optical outburst accompanied by a bright and long-lasting infrared emission.
They're still watching it.
"We saw it start to happen and we've been following it for the last few years," MacLeod said.
MacLeod created the computer model that replicated what researchers saw, giving them a way to study and confirm what happened and anticipate what might occur in similar events in the future. He compared their work to that of police investigators charged with reconstructing a vehicle crash scene.
"The challenge of astronomy is there is no lab where you can replicate a planet falling into its star," he said. "You just have to watch and see what happens, and then reconstruct it on computers after the fact.
While computer modeling shows Earth will experience a similar fate, MacLeod said it won't create the same vibrant display as the Sun expands and absorbs the planets that course around it.
"We won't cause a flare like that," he said. "We're too small to notice as the Sun swallows us. I find that to be the most humbling part of this whole story. But that's 5 billion years from now, so we have more pressing problems."
Married with a young son, MacLeod said working on this project has been the "absolute highlight" of his career so far. It has prompted him to reflect on the people who encouraged him along the way, including his sixth-grade teacher, the late Carolyn Gebbia, and members of Southern Maine Astronomers, a group of professionals and amateurs who mentored him.
And Robert O'Neill of Raymond, a retired science teacher at Greely High School, who MacLeod said expanded his understanding of the scientific process and the joy of doing research.
O'Neill's instruction helped him win three state science fairs and two national science competitions, he said. He went on to graduate from Bowdoin College and the University of California Santa Cruz.
"I feel so lucky and grateful," MacLeod said.
He tries to pay it forward, teaching astronomy courses at Harvard for high school students and freshmen.
O'Neill said he's not surprised by MacLeod's success and described his former student as a "reluctant perfectionist."
"Morgan was interested as long as he was having fun," O'Neill said. "Morgan loved doing research, especially on the planets."
MacLeod said he feels incredibly privileged to work in his chosen field.
"Learning about the range of possibilities out there — that there are planets being swallowed up by their stars," he said. "It doesn't necessarily change our daily existence, but it's a nice reminder to not take anything we're experiencing now too seriously."
At the same time, he said, it also shows how much of what occurs in the universe is inextricably linked.
"It provides a rich understanding of not only where we've come from, but also where we're going," MacLeod said.