How can maps be used to start wars?
- What other countries have disputes over lines drawn on maps?
- How does a sextant help navigators?
- When was the compass invented?
- Have compasses always pointed north?
- What is a compass rose?
- What is an azimuth?
- How, why, and how much does Magnetic North move?
- How much has the magnetic north pole moved?
- How old is the oldest known map?
- What is the oldest map using the word America?
- What is the oldest known map drawn to scale?
- Where is the equator?
Prior to its 1990 invasion of Kuwait, Iraq produced official maps that showed the independent country of Kuwait as Iraq's nineteenth province. Iraq used these maps as justification for its 1990 invasion and attempted annexation of Kuwait (Iraq was actually after Kuwait's oil reserves). Maps have been, and still are, used by a multitude of countries, provinces, and cities to prove ownership of a certain piece of land.
What other countries have disputes over lines drawn on maps?
Japan, China, and Taiwan all have a dispute over the Diaoyu/Senkaku islands in the Pacific Ocean. India and Pakistan have an ongoing dispute over ownership of the northernmost region of Kashmir in India. China has disputed claims of sovereignty by Taiwan. North and South Korea are still in conflict over lines drawn by Korean and American forces that split the country in two.
How does a sextant help navigators?
In 1730, the sextant was invented independently by two men, John Hadley and Thomas Godfrey. Using a telescope, two mirrors, the horizon, and the sun (or another
A "compass rose" is the ornamentation surrounding a compass dial that is divided into the four cardinal directions, and then into further divisions.
celestial body), the sextant measures the angle between the horizon and the celestial body. With this measurement, navigators could determine their latitude while at sea.
When was the compass invented?
As early as the eleventh century, the Chinese were using a magnetic needle to determine direction. At approximately the same time, the Vikings may have also used a similar device. A compass is simply a magnetic needle that points toward the magnetic north pole.
Have compasses always pointed north?
No, they have not. Though compasses always point to the magnetic pole, the magnetic pole has not always been in the north. Every 300,000 to 1 million years, the magnetic pole flips from north to south or from south to north. If compasses had been around before the last time the magnetic pole reversed, their arrows would have pointed south rather than north.
What is a compass rose?
On old maps, the directions of the compass were represented by an elaborate symbol, known as a compass rose. Many of the older compass roses displayed 32 points, representing not only the four cardinal directions (north, south, east, and west) but also 28 subdivisions of the circle (south-west, south south-west, etc.). This directional symbol resembled a rose, hence its name. Though compasses are now often drawn with only the four cardinal directions and the resemblance to the flower is minimal, the directional symbol is still called a compass rose.
What is an azimuth?
Azimuth is another method for stating compass direction. It is based on the compass as 360 degrees, with north at 0 degrees, east at 90, south at 180, and west at 270 degrees. You can refer to a direction as "head 90 degrees" instead of "head east."
How, why, and how much does Magnetic North move?
Scientists aren't sure why the Earth's magnetic pole moves, only that it does. The amount of movement varies, but it's never more than a few miles each year.
How much has the magnetic north pole moved?
Since it was documented in 1831 by James Ross to be slightly north of 70 degrees north latitude, it has moved to north of 80 degrees north latitude at an average rate of more than 24.9 miles (40 kilometers) per year.
How old is the oldest known map?
Circa 2700 b.c.e., the Sumerians drew sketch maps in clay tablets that represented their cities. These maps are the oldest known maps.
What is the oldest map using the word America?
The map, acquired by the Library of congress and dated 1507, incorporates many of the findings of the Italian explorer Amerigo Vespucci. The map was thought to be lost, but was rediscovered in 1901, and was kept in a castle in Wolfegg, Germany, for more than 350 years.
What is the oldest known map drawn to scale?
In the sixth century b.c.e., the Greek geographer Anaximander created the first known map drawn to scale. His map was circular, included known parts of Europe and Asia, and placed Greece at its center.
Where is the equator?
The equator is the line located equidistant between the North and South Poles. The equator evenly divides the Earth into the northern and southern hemispheres and is zero degrees latitude.
Do other planets have longitude and latitude lines?
Yes, scientists have divided the other planets and their moons into longitude and latitude systems like the Earth. They use these lines just as they do on Earth: to pinpoint exact locations on the planet or moon.