How to Participate

Report on the 20th of every month and on each equinox and solstice. Track changes in daylight length over the course of the year on the daylight map. Explore how daylight length changes in your part of the world as the Earth revolves around the Sun.

Share and compare seasonal observations with people around the globe. Are you noticing any seasonal signs that the spring equinox is only a few months away?

How to Report your Day Length (Photoperiod)

Step 1: Look up your sunrise/sunset on the 20th of every month.

Step 2: Calculate the length of time between sunrise and sunset. 

Step 3: Report your daylight length on the 20th of every month and on each equinox and solstice.

Step 4: Explore the Daylight map and compare your part of the world with other locations as the Earth revolves around the Sun.