There are special places on Earth where you may see no shadows (meaning the Sun is at your zenith). Where and when would that be?

1. North and South Poles at winter and summer solstices
   
2. North and South Poles at fall and spring equinoxes
   
3. Anywhere along the Equator at winter and summer solstices
   
4. Anywhere along the Equator at fall and spring equinoxes
   
5. It never happens.