*Please note: Our spring 2020 Mystery Class challenge is a replay of a previous year's challenge. On this page, you have open access to all clues (Weeks 1-11). We will reveal the locations of the 10 Mystery sites on April 13, 2020.
Continent, Country, City
Use photoperiod to estimate latitude. Calculate photoperiod using sunrise/sunset data.
From the Mystery Sites
Use the weekly sunrise/sunset data from the 10 Mystery sites to calculate the photoperiod for each site. Record and graph the photoperiods.