Understanding Major Domains of the Earth
The Earth is divided into four major domains:
- Lithosphere: This is the solid outer layer of the Earth, comprising the crust and upper mantle. It includes landforms, mountains, and soil.
- Hydrosphere: This encompasses all water bodies, including oceans, rivers, lakes, and groundwater. The hydrosphere is vital for life and climate regulation.
- Atmosphere: The layer of gases surrounding the Earth, essential for weather patterns and climate. It consists of multiple layers, including the troposphere, stratosphere, and mesosphere.
- Biosphere: This includes all living organisms on Earth, interacting with the lithosphere, hydrosphere, and atmosphere.
Latitudes and Longitudes
Latitudes and longitudes are a grid system used to pinpoint locations on Earth:
- Latitude: Measures north or south of the equator, ranging from 0° at the equator to 90° at the poles. It is divided into northern and southern hemispheres.
- Longitude: Measures east or west of the Prime Meridian, ranging from 0° to 180°. It divides the Earth into eastern and western hemispheres.
The Solar System Overview
The solar system consists of the Sun and celestial bodies orbiting it:
- Planets: Eight major planets, including Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. They vary in size, composition, and distance from the Sun.
- Dwarf Planets: This category includes Pluto, Eris, and others, which are smaller and do not clear their orbits.
- Moons: Natural satellites that orbit planets, with diverse characteristics and geological features.
- Asteroids and Comets: Small celestial bodies found mainly in the asteroid belt and beyond, contributing to our understanding of the solar system's formation.
This foundational knowledge is essential for UPSC preparation, providing insights into Earth's structure and our place in the universe.