NASA | Looking Down a Well: A Brief History of Geodesy

The video explores the evolution of geodesy, starting with Eratosthenes' method of measuring Earth's circumference using shadows and distances between cities. It highlights the development of geodesy through triangulation, mapping, and the realization that Earth is not a perfect sphere. The video also discusses the role of technology, such as radio telescopes and satellites, in advancing geodesy, allowing for precise measurements of Earth's crust, gravity, and ocean tides. Geodesy has had a significant impact on navigation, exploration, and understanding Earth's dynamics, from ancient times to the present.

Who is credited with the early development of geodesy by measuring the Earth's circumference?

• Aristotle

• Galileo

• Eratosthenes

• Pythagoras

What was one of the key uses of geodesy in navigation?

• Predicting weather patterns

• Determining latitude and longitude

• Calculating the speed of light

• Measuring the depth of oceans

How did geodesy contribute to the construction of railroads?

• By determining the best routes through mountains

• By predicting train speeds

• By providing materials for construction

• By designing train engines

What modern technology uses geodesy to study the Earth's crust and day length changes?

• Radio telescopes

• Seismographs

• Sonar systems

• Weather balloons

What can satellites help us monitor in relation to geodesy?

• The height and shape of oceans and ice sheets

• The color of the sky

• The migration patterns of birds

• The growth of forests