The Earth turns to the east as it rotates. It spins 1 degree longitude every 4 minutes. On the equinox, locations at the same longitude experience sunrise at the same time.
Time and Longitude
Locate the Prime Meridian and Greenwich, England on the map.
- Longitude: How far east or west of the Prime Meridian do you live (in degrees)?
- Time: What is the time difference between Greenwich, England and your home town (in hours and minutes)?
Time Clues on March 9
These facts will help you use the time clues to estimate the longitude of the Mystery sites:
- The Prime Meridian is the reference line you will use for measuring longitude.
- Greenwich, England is the reference point you will use for measuring time.