Earth and our Solar System Review

Compare the size of our solar system to the size of the milky way galaxy

Like a single grain of sand compared to the whole U.S.

Describe two main theories about the formation of the solar system

Ptlomey- Geocentric- The Earth is in the middle of the universe

Copernicus- Heliocentric- The sun is in the middle of the solar system

Identify the contributions made by early astronomers (4)

Ptrolemy: Thought of the geocentric model which the earth was the center of the universe

Copernicus: Thought of the heliocentric which the sun is the center of the solar system

Galileo: Found proof, 4 moons around jupiter

Kepler: Planets orbit in ellipeses

Compare and contrast the physical properties of mass, density, and volume

Mass: The Amount of matter in an object

Density: Mass divided by volume

Volume: The Amount of space an object takes up

Explain when and how the solar system was formed

4.6 billion years ago from a massive cloud of gas and dust called solar nebula

Classify the evidence scientists have to support the nebular hypothesis

The evidence is the the similar direction of planets' orbits, the flat shape of the solar system, and the making of planets and moons

Show how to use the following scientific terms efficiently: Radioactive decay, isotope, and half-life

Unstable isotope breaks down over time and its half-life is the time it takes for half of the isotope to decay into a more stable form

Identify the planets in order and be able to name something unique about each

Mercury: Smallest planet

Venus: Hottest planet

Earth: Has life

Mars: The Tallest volcano in the solar system

Jupiter: The Largest Planet

Saturn: Huge rings

Uranus: Sideways rotation

Neptune: Strong winds

Explain why pluto is no longer considered a planet but is now classified as a dwarf planet

Not big enough and doesn’t clear it’s orbit

Outline and explain three key ingredients for needed life

1. Liquid water

2. Source of energy

3. Moderate temperature

Analyze the habitable zone

The area around a star where a planet can have liquid water on its surface

Examine the extra solar planets. Identify what scientists determine as the characteristics on these distant planets

Examining their size, type, temperature, orbit, and atmosphere to determine if their can be life on it

3 types of galaxies

1. Elliptical

2. Spiral

3. Irregular

Accretion is

Build up of gases to make larger objects

Galaxy is

A large collection of stars and planet systems

Astronomical Unit

The distance between the earth and sun

Ellipse is

Fancy word for oval, this is the shape of planet orbits

Planetary System

Stars with planets around it

Planetary nebular theory

Our solar system formed from a big cloud of dust and gas

Planetsimals (3)

Chunks of rocks in space, smaller than normal planets, and became fused with earth

Theia

The planetesimal made of the moon

Radioactive decay

Elements that decay at specific rates

Half-life

The time it takes for ½ of the material to decay

Dwarf planets

Planets that haven’t been cleared out, but still orbit the sun

Exoplanets

Planets outside our solar system

Where did oceans come from

Comets and volcanoes

Comets

Made of of ice, which orbits the sun, and continues to bombard earth giving it O2

Where did the atmosphere come from

Outgassing or accretion

Outgassing

The release of trapped gassing when heated

What 2 things were made with the collision of earth

1. The moon

2. Seasons created by titled axis