Clues for Spring 2020

Photoperiod

Time Continent, Country, City

Use photoperiod to estimate latitude. Calculate photoperiod using sunrise/sunset data.

Mystery Class Data

Sunrise/sunset data from the 10 Mystery sites will be posted here weekly on these dates. Record and graph the photoperiod for each site.

  • January 27
  • February 3
  • February 10
  • February 17
  • February 24
  • March 2
  • March 9
  • March 16
  • March 23
  • March 30
  • April 6

 

Your Local Data

Look up your own sunrise/sunset for the dates above. Calculate, record and graph your photoperiod. How does it compare to the Mystery Sites?

 

 

Use Time Clues to estimate longitude:

  • March 9

Narrow the search from continent to country to city. Clues will be posted weekly on these dates.

  • March 16 (continent/region)
  • March 23 (country)
  • March 30 (state/province)
  • April 6 (city/town)