Understanding Earth’s Surface, Regions, and Movements
The Field of Study
The series of phenomena that take place within the Earth’s surface. The interaction of human actions and nature creates a variety of natural and cultural landscapes.
General Geography
Studying the laws, principles, relationships, and overall distributions of cultural and natural phenomena that occur on Earth’s surface.
Geography Branches
- Mathematical Geography
- Physical Geography
- Human Geography
Regional Geography
Studied to specify the differences and similarities between different regions of the Earth’s surface, such as continents and climatic zones.
Importance of Geography
- Encourages the love of country
- Encourages peaceful coexistence between peoples
- Encourages better understanding and exploitation of natural resources
- Contributes to improving conditions and explanations
- Helps perceive national and global issues in their true proportions
Terrestrial Surface
The vertical zone where the lower layers of the atmosphere, lithosphere, and hydrosphere contact, and where life develops.
Geographical Landscape
The portion of an area on the Earth’s surface visible in photographs, with its own characteristics.
Geographic Region
A portion of the land surface differentiated from others by its specific characteristics, which can refer to aspects of the field and cultural aspects of the population.
Street Map: Determine Coordinates
To locate a point on a surface, coordinates are necessary to establish its position using latitude and longitude.
Choice of Projections
Cartographers use projections to represent the characteristics of the spherical surface of the Earth accurately on a flat surface or map.
Select Scale
It is very important because it is fundamental to interpret and relates the actual distance or length between sites or selected sites and the length shown on the map.
Details of Topography
It is very important to describe the forms and levels of the Earth’s surface, such as hills, mountains, plateaus, and plains.
The Sun
The Sun is an average star that takes 220 million years to orbit the galaxy. It has a rotation period of approximately 25 days.
- Temperature: 5,700°C (surface), 15 to 20 million °C (inside)
- Composition: Helium (27%), Hydrogen (71%), Heavy elements (2%)
Solar Layers
- Core: Subjected to high temperatures, it is the source of the Sun’s energy. Hydrogen is converted into helium here.
- Photosphere: The area of high-power light that surrounds it, about 6300°C. Sunspots form here.
- Chromosphere: The inner layer of the atmosphere, with a diameter of 1000 to 8000 km. It is pink and composed of calcium, helium, and hydrogen. Solar flares occur here, which can affect communication.
- Solar Corona: The outside of the solar atmosphere, with a very irregular contour. It is less hot and has very rarefied gases. Temperature of 2.2 million °C.
Earth’s Radii and Measurements
- Equatorial Radius: 6,378 km
- Polar Radius: 6,356 km
- Mean Radius: 6,370 km
- Equatorial Circumference: 40,076 km
- Polar Circumference: 40,009 km
- Equatorial Diameter: 12,713 km
- Minimum Sun Distance: 147,094,041 km
- Maximum Sun Distance: 152,243,942 km
- Mass: 6,000 trillion tons
- Area: 5,100,101,934 km²
Movements of the Earth
- Rotation: From west to east, 23h 56′ 4”
- Translation:
- January to July: Perihelion, Earth is closer to the Sun.
- July to December: Aphelion, Earth is farther from the Sun.
- Nutation: A wobble of the Earth’s axis caused by the Moon’s force, occurring every 18 years and 6 months.
- Precession of Equinoxes: Due to the Earth’s axis being slightly tilted with respect to the ecliptic, the axis describes a complete circle at the poles in 28,000 years.
Types of Years
- Tropical Year: Based on the Sun, it lasts 365 days, 5 hours, 48 minutes, and 46 seconds.
- Sidereal Year: Based on a star, it lasts 365 days, 6 hours, 9 minutes, and 10 seconds.
- Calendar Year: The difference between the two.
Time Zones
In 1912, time zones were established in Paris, dividing 360 degrees by 24 hours, resulting in 15 meridians. Each hour, the Earth travels 15 degrees, which is called a time zone.