Physicists at MIT have developed and released a $100 muon detector that you can build at home, allowing you to sense deep space bombardment on something that looks like a TV remote. The CosmicWatch is basically a little box that can detect high-energy cosmic rays as they hit the Earth’s atmosphere and decay into muons.
Muons hit the Earth in a “light drizzle” say the device’s creator, Spencer Axani. He and the other members of the team, Katarzyna Frankiewicz and Paweł Przewłocki of the National Centre for Nuclear Research in Warsaw as well as Janet Conrad at MIT, created an entire DIY system for building and measuring muons as they pass through the detector. You can find the DIY plans here and even download the project code on Github. It uses an Arduino Nano and a silicon photomultiplier “to detect scintillation light emitted from charged particles as they pass through the scintillator.”
Axani has attached the device to weather balloons and even sent teams of students into the Boston subway to see how drastically the count changed. They plan on sending a detector up in a suborbital rocket.
“At sea level, you might see one count every two seconds at sea level, but on a plane at cruising altitude, that rate increases by about a factor of 50 — a dramatic change,” said Axani. “From the measured rate you can back-calculate what the actual altitude of the plane was.”
You can also use this device to map through walls, allowing you to make a map of another floor simply by seeing where the muons are more prevalent.
“That’s something I’d like to try out at some point, maybe to map out the office on the floor above me,” said Axani.