How Did Vikings Navigate Using Sunstones?

💡 The Answer

• Sunstones were likely calcite crystals that could polarize light, revealing the sun's position even on overcast days.
• By observing the sky through a sunstone, Vikings could determine the direction of the sun to navigate the open ocean.
• Archaeological evidence includes a sunstone found in a 16th-century shipwreck off the coast of Alderney in the English Channel.
• This navigational technique allowed Vikings to make long voyages to Greenland and North America long before the compass.