Public radio station WNYC invites families, armchair scientists and lovers of nature to join in a bit of mass science: Track the cicadas that emerge once every 17 years across New Jersey, New York State and the whole Northeast by building homemade sensors and reporting your observations.

Magicicada Brood II will make its 17-year appearance when the ground eight inches down is a steady 64 degrees Fahrenheit/17.8 degrees Celsius. Help predict the arrival by planting a homemade temperature sensor in the ground and reporting your findings back to WNYC. We'll put them on a map and share your observations of this once-in-a-generation discovery with our entire community.

The whole detector costs about $80 in parts and takes about two hours to build. You'll want it in the ground by mid-April, the earliest the cicadas are likely to emerge.