Last month, a UChicago-led mission known as Payload for Ultrahigh Energy Observations, or PUEO, landed a few hundred miles from the South Pole after a journey aboard a NASA balloon. PUEO flew 120,000 feet above the ground on the hunt for some of the highest energy particles in the universe—neutrinos.
Signatures of these and other high-energy particles from outer space, known as astroparticles, could give us information about some of the most violent events in the universe, such as supermassive black holes or star explosions. They also have the potential to unlock mysteries closer to home, including information about the core of our planet, lightning formation, and water on the moon.
In this spring’s Compton Lectures, UChicago scientist Keith McBride will illuminate how these “messengers from the universe” can answer questions about the farthest reaches of our universe, as well as be harnessed as practical tools to understand our planet.
“We want to understand how these particles are getting here, where they’re coming from, how old they are, and what they can tell us about their journey,” said McBride, who has worked on multiple astroparticle-hunting missions.
During the Compton series, McBride will discuss how high-energy astroparticles like neutrinos and cosmic rays are not only helping us understand the universe but also helping us make measurements of extremely dense objects. Muons, for example, have been used to peer inside large structures like volcanoes and pyramids, and researchers are now using neutrinos to help understand the earth’s composition.
“Since neutrinos interact with dense materials, you can measure how many neutrinos have passed through the earth to potentially help us make a map of the core,” said McBride.
In another lecture in the series, McBride will discuss one of the leading theories about how lightning is formed.
“We know that lightning occurs when charged particles in the atmosphere go to ground. But what starts the charges moving in the first place?” said McBride. “Cosmic rays could be creating the seeds for lightning.”
Payton Linton, McBride’s collaborator and senior graduate student at The Ohio State University, will give a guest lecture on May 9, showcasing how a proposed lunar orbiter will use interactions of cosmic rays to help us detect ice beneath the moon’s surface.
“What a lot of people don’t realize is that particle physics has interdisciplinary applications. We can take what we’ve learned about astroparticles and their interactions to better understand the world around us,” said McBride.
McBride, a UChicago postdoctoral researcher, led the development of major portions of the neutrino-hunting PUEO instrument. He also worked on another balloon mission, the High-Energy Light Isotope eXperiment (HELIX), which landed in June 2024 after six days in space.
The free public talks run every Saturday from March 28 through May 16 at 11 AM.
They are held at the Kersten Physics Teaching Center, 5720 S. Ellis Ave., in Room 106, and will also be broadcast online.
—Adapted from an article first published by the Physical Sciences Division.