Earths Place in the Universe

Standard 2a and 2b Students know the solar system is located in an outer edge of the disc- shaped Milky Way Galaxy, which spans 100,000 light years Students know galaxies are made of billions of stars and comprise most of the visible mass of the universe.

Galaxies Are composed of billions and trillions of stars and make up the visible mass of the universe.

Galaxies

Milky Way Galaxy Sun Alpha Centari

The Milky Way Galaxy A disk made of stars orbiting a central point in the disk. Our sun is just 1 of 100 billion stars that make up the milky way. It is difficult to determine its size and shape because we are located in the milky way. The solar system is located in an outer edge of the disc-shaped Milky Way Galaxy, which spans 100,000 light years.

Classification of Galaxies Dislike galaxies with spiral arms were called spiral galaxies. Galaxies that are inflated and do not have arms are called elliptical galaxies. Irregular galaxies fit into both elliptical and spiral galaxies

Standard 1e Students know the Sun is a typical star and is powered by nuclear reactions, primarily the fusion of hydrogen to form helium.

The Sun

The Sun is the largest object in the solar system.  99.8% total mass Typical star, many other stars are similar but smaller in size.  Top 10 % of largest stars

Suns composition 70% hydrogen 28% helium 2% other metals Changes as sun converts hydrogen into helium in the core.

Nuclear Reactions Typical nuclear reaction is where several sub-atomic particles come together, interact, and several particles emerge. There is several of these reactions that take place on the sun.

This is the type of nuclear reaction taking place on the sun. 4 hydrogen as they change to helium it is called hydrogen burning. Hydrogen is “fuel”. There is no real burning. End result is helium. Mass on the right is less than the left. End up with energy produced.  Gamma rays  Energy of motion of the suns particles Build up to fusion reactions

Review Sheet What is the largest object in the solar system? Explain the composition of the sun. Describe the process that takes place in the sun. What gases are involved in nuclear fusions? Explain what happens when the gases run out in a star.

Standard 1a Students know how the differences and similarities among the sun, the terrestrial planets, and the gas planets may have been established during the formation of the solar system.

Draw and label the inner and outer solar system on your notes.

Identify the Inner and Outer Solar System Planets

How Many Planets? You are here ?

Solar System Consists of: The Sun Nine planets 130 planet satellites (moons) Comets Asteroids

Identify the components or things that make up our solar system. Bonus Question: Explain how the different components of the solar system interact together.

Terrestrial planets Rocky planets Venus, Mercury, Pluto, Earth and Mars Composed primary of rock and metal High densities Slow rotation Solid surfaces No rings Few satellites

Identify the terrestrial planets. Name four characteristics of a terrestrial planet.

Gas Planets Jupiter, Venus, Saturn, Uranus, and Neptune Composed of hydrogen and helium Low densities Rapid rotation Deep atmospheres Rings Lots of Satellites

Identify the gas planets. Name four characteristics of a gas planet.

Discuss the differences between gas and terrestrial planets.

Standard 1b Students know the evidence from Earth and moon rocks indicates that the solar system was formed from a nebular cloud of dust and gas approximately 4.6 billion years ago.

What is the origin of the solar system? It is generally agreed that it condensed from a nebula of dust and gas. But the details are far from clear.nebula

Explain the theory of the origin of the solar system.

Review Sheet- You and your partner will write the question and answer the following questions. 1. Discuss the differences between terrestrial and gas planets. 2. Explain the theory dealing with the origin of the solar system. 3. Using the following words; identify, explain, name, what, and discuss to create five questions for your review sheet. Remember to answer your questions. This is your ticket out of here!

Steps of solar system formation Heats up and compresses. (100,000 years)

Steps of solar system formation Become protostar Radiates energy away from star.

Steps of solar system formation Gases cool off: metal, rock and ice condenses.

Steps of solar system formation Dust particles collide creating asteroids.

Steps of solar system formation Gravitational pulls begins.

Steps of solar system formation Solar nebula disturbed and collapses under own gravity

Steps of solar system formation As Nebula cools the star generates solar wind

Explain the steps of how the solar system was created.

Standard 1c Students know the evidence from geological studies of Earth and other planets suggest that the early Earth was very different from Earth today.

Early Earth

Very hot Constant volcanism Atmosphere consists Helium and hydrogen Cooling Change Heat displaced to space Condensation of water due to volcanic ash

Present Earth Atmosphere  78% Nitrogen  21% Oxygen .03% Carbon Dioxide  Miscellaneous Gases Stable biological conditions

Standard 1f Students know the evidence for the dramatic effects that asteroid impacts have had in shaping the surface of planets and their moons and in mass extinctions of life on Earth.

Asteroids Rocky metallic bodies that revolve around the sun When an asteroid hits it changes everything forever When asteroids hit planets it creates huge depressions called craters.

Meteor Crater in Arizona Hit happened 50,000 years ago An asteroid impact kills all living organisms. Theory of Dinosaur extinction involves the impact of an asteroid on our atmosphere

Asteroids do bring other things:  Chemical components of life  Water

Explain the negative and positive impacts that asteroids have on earth.

Standard 2c Students know the evidence indicating that all elements with an atomic number greater than that of lithium have been formed by nuclear fusion in stars.

What is an Element? An element is a fundamental substance which can not be further subdivided without destroying its identity.

Where did elements come from? All elements originated from stars long ago. Elements were created by nuclear fusion.  The process of fusing together light elements into heavier elements. This process is found in stars and the sun.

What is an element? Where do elements originate from?

Review Sheet- You and your partner complete 1. Discuss the differences between past and present earth. 2. Explain how elements are formed. 3. Create questions using the words: what, how, and explain. Answer the questions. This is your ticket out the door.

Standard 2d Students know that stars differ in their life cycles and that visual, radio, and X-ray telescopes may be used to collect data that reveal those differences.

Star Life Cycle Formation of a star begins with a cloud of interstellar gas and dust called a nebula  Collapses on its self from its own gravity Hot condensed object in the center called a protostar.  Condensed object becomes a new star  This is when it is the brightest

Now what? Fusion begins when the inside of the star is hot enough  Convert hydrogen into helium Becomes stable by producing internal heat to balance gravity.

Stars expand as they grow old. As the core runs out of hydrogen and then helium, the core contacts and the outer layers expand, cool, and become less bright. It will eventually collapse and explode. Its fate is determined by the original mass of the star; it will become either a black dwarf, neutron star, or black hole.

Black Holes – dead stars

Discuss with your partner how a star is formed.

Sun Like Star Life Cycle Star Red Giant- Luminousity Increases and Surface Temperature Decreases Planetary Nebula- outside gas expands and center looks white and hot. White Dwarf- Stable despite lack of nuclear reactions

List the steps of a sun like star.

Huge Star Red Giant Supernova- Do not lose enough mass to become a white dwarf.  Center violently collapses Neutron Star- High density, created from explosion from the supernova

Turn to your partner and discuss. Discuss the step of the life cycle of a huge star.

Giant Star Red Star Supernova Black Hole- Too massive to form neutron stars, resistance is to strong and the star collapses forever. Small dense object is left behind.

Explain the steps of a giant star’s lifecycle.

Review Sheet- You and partner complete the review sheet Discuss the differences between past and present earth. 2. Explain how elements are formed. 3. Create 3 questions using the words: what, describe, and explain. Answer the questions. This is your ticket out the door.