Imagine holding the universe in your hand. Thanks to an ingenious invention by University of Delaware physics professor Spencer Axani, that's now possible for students, educators, and scientists everywhere.

CosmicWatch is changing the game in particle physics. About the size of a box of crackers and costing just $100 to build, this remarkable device detects muons—tiny particles created when cosmic rays from distant exploding stars collide with Earth's atmosphere. Every time a space particle passes through the detector, it lights up and records the event, making the invisible visible.

What makes this invention truly special is how it's opening doors that were previously locked. Traditional muon detectors are bulky and expensive, often the size of a small bookshelf. CosmicWatch puts the same scientific capability in the palm of your hand, transforming who can participate in groundbreaking physics research.

"CosmicWatch detectors allow us to do far more physics at a dramatically lower cost, in a compact and portable form, opening the door to many new kinds of experiments and outreach opportunities," Axani explains with evident enthusiasm.

The story behind CosmicWatch is equally inspiring. Axani initially designed it in 2017 for Antarctica's IceCube observatory, but quickly realized its potential to democratize science education. Since joining UD in 2022, he's continued refining the device, recently releasing its third version with enhanced capabilities including environmental monitoring and faster data collection.

Students are at the heart of this innovation. Doctoral student Masooma Sarfraz, who helped develop the latest version, describes the experience as transformative. "Even though I had studied cosmic rays, I didn't fully appreciate the rich physics behind the working of these detectors," she shares. For her and countless other students, CosmicWatch bridges theoretical knowledge with hands-on discovery.

The educational impact extends from high schools to universities. Students build their own CosmicWatches from scratch, learning electronics while designing their own experiments. One creative doctoral student, Musarate Shams, even sent his customized detector skyward on a weather balloon, recovering it miles from the launch site to study how cosmic ray patterns change with altitude.

Beyond education, CosmicWatch is contributing to serious scientific endeavors. The devices are being used in international astrophysics experiments, including dark matter research in New Mexico and the NuDot experiment at UD. Future versions will even venture into space aboard rockets and spacecraft to measure cosmic rays directly.

The applications extend to Earth-based discoveries too. Muon detection technology has already revealed hidden chambers in Egypt's Great Pyramid of Giza, demonstrating how these space particles can help us see through solid matter without causing any damage.

What's most heartening about CosmicWatch is its philosophy: that world-class science shouldn't be restricted by cost or accessibility. By putting powerful research tools within reach of anyone with curiosity and $100, Axani is nurturing the next generation of physicists and astrophysicists.

As these tiny detectors multiply across classrooms and laboratories worldwide, they're doing more than counting particles—they're sparking wonder, enabling discovery, and proving that sometimes the biggest scientific breakthroughs come in the smallest, most accessible packages.