Earth and Space Sciences: Earth Processes, Weather, and the Solar System
What to know
Earth has layers - crust, mantle, outer core, inner core - and its surface is reshaped by the rock cycle, weathering (breaking rock down), erosion (moving the pieces), and deposition (dropping them). Soil forms slowly from weathered rock plus decayed plant and animal material.
The water cycle moves water through evaporation, condensation, precipitation, and collection, powered by the Sun. The Sun is Earth's main source of energy and drives weather. Weather is the day-to-day condition of the atmosphere; climate is the long-term pattern of an area. The atmosphere has layers and protects life.
In the solar system, planets orbit the Sun, and moons orbit planets. Earth's rotation on its axis once every 24 hours causes day and night; revolution around the Sun once each year combines with Earth's tilted axis to cause the seasons. Moon phases repeat about every month as the Moon orbits Earth. Natural resources are renewable (sunlight, wind, water, trees) or nonrenewable (coal, oil, natural gas), and fossils give evidence of organisms that lived long ago.
Traps
- Saying seasons happen because Earth is closer to the Sun - tilt and revolution cause them.
- Explaining moon phases as Earth's shadow - that is an eclipse.
- Using weather and climate interchangeably.
- Mixing up weathering (breakdown in place) with erosion (transport away).
- Thinking day and night come from Earth's orbit rather than its rotation.
Worked example
A student notices it is dark at 9 p.m. and light at 9 a.m. Cause: Earth rotates on its axis, turning that location toward and away from the Sun once every 24 hours.