the shadow of the earth projected on the moon during a lunar eclipse appears to be curved. Second, the elevations of stars change as one travels north or south, while certain stars visible in Egypt cannot be seen at all from Greece. The actual radius of the earth was determined within one...
Raymarine Element HV chartplotters with HyperVision 1.2 Megahertz sonar give you the upper hand when hunting for fish and their habitat, delivering the sharpest fish finder view of the underwater world.