Chapter 3 defining units of measure Flashcards Preview

Oceanography > Chapter 3 defining units of measure > Flashcards

Flashcards in Chapter 3 defining units of measure Deck (7)
Loading flashcards...
1

Ptolomy

The Greek philosopher Ptolomy plotted latitude on a map as degrees north from the equator as did many others

2

On land

longitude can be determined through astronomical observations and surveys (still hard to do)

3

On sea

longitude requires a clock to measure time as well as the measurement of the positions of celestial objects (e.g. Sun)

4

The challenges

Earth rotates 360° per day or 15° per hour

5

About the earth

You find longitude with stars and a clock

6

Chronometers

These early clocks were called chronometers

7

Prime meridian

was designated to pass through the Greenwich Observatory in England and is our 0° longitude line.