Universe and Astronomy Quiz

Universe, Astronomy and Solar System

• The solar system consists of the Sun and celestial bodies including planets, moons, asteroids, comets, and meteoroids.
• Kepler’s Laws of Planetary Motion describe the movement of planets in their orbits around the Sun.

Kepler’s Laws of Planetary Motion

• First Law: Planetary orbits are elliptical, with the Sun located at one focus of the ellipse.
• Second Law: A line joining a planet to the Sun sweeps out equal areas in equal time intervals, indicating varying speeds in different parts of the orbit.
• Third Law: The square of a planet's orbital period is proportional to the cube of the semi-major axis of its orbit, establishing a mathematical relationship between distance and orbital time.

Geology

• The study of rocks and minerals is fundamental in understanding Earth's composition and processes.

Rocks Classification

• Igneous Rocks: Formed from solidified magma or lava.
  • Intrusive Igneous Rocks: Example includes granite, which crystallizes slowly within the Earth.
  • Extrusive Igneous Rocks: Example includes obsidian, formed from rapid cooling of lava above ground.
• Sedimentary Rocks: Developed from erosion and deposition of materials over time.
  • Clastic Sedimentary Rocks: Created from inorganic debris, such as sandstone.
  • Organic Sedimentary Rocks: Formed from the remains of living organisms, e.g., limestone and coal.
  • Chemical Sedimentary Rocks: Originates from the precipitation of dissolved materials, like rock salt.
• Metamorphic Rocks: Produced when existing rocks are altered by heat, pressure, and chemical processes.
  • Foliated Metamorphic Rocks: Feature visible layers or striations due to directional pressure; an example is slate.
  • Non-foliated Metamorphic Rocks: Display irregular patterns with no layered appearance; marble is a notable example.

Rock Cycle

• Each rock type (igneous, sedimentary, metamorphic) can transform into another through specific geological processes.
• Igneous and sedimentary rocks become metamorphic rock when subjected to high pressure and heat.
• Sedimentary and metamorphic rocks can transition into igneous rock by melting back into magma.
• Igneous and metamorphic rocks can form sedimentary rock through the process of erosion.

Minerals

• Naturally occurring substances in the Earth, characterized by a definite chemical composition and structure.
• Over 3000 different minerals identified; some are rare gemstones (e.g., diamond), while others are common (e.g., quartz).

Weathering Processes

• A destructive process that alters rocks through exposure to different environments.
• Three main types of weathering: mechanical, chemical, and biological.

Mechanical Weathering

• Rocks are broken down into smaller clasts of the same composition.
• Fracturing occurs like a hammer, resulting in angular clasts.
• Abrasion functions like sandpaper, smoothing and rounding the rough edges of rocks.

Chemical Weathering

• Changes minerals chemically to achieve greater stability with surface conditions.
• Typically produces smaller pieces with different compositions, with clay being the most common outcome.

Biological Weathering

• Involves the influence of living organisms (plants and animals) on the weathering process.
• Acts in conjunction with mechanical and chemical weathering rather than being a standalone process.