There are more galaxies in the universe than anyone ever expected. Unfortunately, they all showed up at once.
When the first images from the James Webb Space Telescope (JWST) began returning data in 2022, Brant Robertson and his colleagues did what astronomers have always done: They stared at the sky and tried to understand what they were seeing. This time, the sky arrived as terabytes.
“There were galaxies everywhere,” Robertson recalled. “So many, and so far away, that we were genuinely shocked.”
Robertson is a professor of astronomy and astrophysics at the University of California, Santa Cruz, where he leads a team studying how the earliest galaxies formed after the Big Bang.
It’s the kind of work Spring Astronomy Day was made for — and thanks to the datasets his team releases publicly, anyone marking the occasion this year can explore the early universe in more depth than was possible even a few years ago.
Over the past several years, his group has broken the record for the most distant known galaxy more than once, each time pushing observation closer to the universe’s first light.
Without computation at this scale, the data would just pile up.
Observational limits require calculation. Copernicus used mathematics to resolve observational inconsistencies. Robertson does the same using computational models.
JWST is the most powerful observatory ever launched, observing in infrared, capturing light that has traveled for more than 13 billion years. Each deep-field image is crowded with hundreds of thousands of galaxies, some of them 13 billion years old.
That abundance is the problem.
“These datasets are far too large and complex for humans to analyze by hand,” Robertson said. “Even teams of experts would take years to do what now needs to happen in days.”
