Which instrument was used to determine latitude by measuring the position of the stars?

Which instrument was used to determine latitude by measuring the position of the stars?

• A. Trebuchet
• B. Vikings
• C. Odin and Thor
• D. Mariner's Astrolabe

Answer: (D)

Determining your latitude at sea relies on measuring how high a star sits above the horizon. The mariner's astrolabe was designed for this exact purpose: it lets a navigator sight a star and read its altitude, the angle between the star and the horizon. With that angle and knowledge of the star’s position (its declination) for the date, you can determine your latitude. Polaris was especially useful in the Northern Hemisphere because its altitude closely matches latitude. Other options don’t fit this purpose: a trebuchet is a siege engine, Vikings refers to people rather than an instrument, and Odin and Thor are figures from myth. The mariner’s astrolabe is the historical tool built specifically to measure stellar altitude to find latitude.

Determining your latitude at sea relies on measuring how high a star sits above the horizon. The mariner's astrolabe was designed for this exact purpose: it lets a navigator sight a star and read its altitude, the angle between the star and the horizon. With that angle and knowledge of the star’s position (its declination) for the date, you can determine your latitude. Polaris was especially useful in the Northern Hemisphere because its altitude closely matches latitude.

Other options don’t fit this purpose: a trebuchet is a siege engine, Vikings refers to people rather than an instrument, and Odin and Thor are figures from myth. The mariner’s astrolabe is the historical tool built specifically to measure stellar altitude to find latitude.