Galaxy “Thoughts are like burning stars, and ideas, they flood, they stretch the universe.” ― Criss Jami By: Gurneet Gill and Charndeep Chattu

By the end of 10.2 You will learn…. The 3 types of Galaxies The 2 types of Clusters The differences in Galaxies About Edwin Hubble/ Hubble Space Telescope

What’s a Galaxy? A Galaxy contains gases, dust, and billions of stars that are held together by a gravitation attraction. Earth is in the Milky Way which is a galaxy.

Differences in Galaxies Have different sizes, masses, colours, brightness, and speed of spin. Number of stars, type of stars, and amount/type of gas and dust make up a galaxy. Some grow larger while others stay small. More a galaxy spins the flatter it will be.

Types of Galaxies (cont.) There are 3 common types of Galaxies: Spiral Galaxy Has many long ‘arms’ spiraling out of a center core. Center core is made of old stars. From a side view spiral galaxies look flat and long. Spiral GalaxySide View of Spiral Galaxy

Types of Galaxies (cont.) Elliptical Galaxy Range in shape from a perfect sphere to a stretched out sphere Contain some of the oldest stars in the universe.

Types of Galaxies Irregular Galaxy Looks like a bunch of random stars close by. Composed of new stars and adult stars.

Clusters (cont.) Many galaxies contain 2 types of distinct formations of stars: Globular Cluster made of about 1 million stars held together by gravity in a spherical shape.

Clusters Open Cluster: Made of a few hundred-few tens of thousand of stars.

Edwin Hubble He was an astronomer. In 1925 he thought he was looking at a bright nebula but he was actually looking at another galaxy. Astronomers estimate there is about 125 billion. galaxies. Above is a nebula (made of dust and gas). Some nebulae is where stars are born.

Hubble Space Telescope Transmits images of galaxies to earth. Above is a picture taken by a Hubble telescope.

Where are we in the Milky way? We’re in the outer arms of a spiral galaxy. Our solar system is approximately 28,000 light years away from the center. A light year is the distance that light can travel in 1 year.

5 QUESTIONS (cont.) 1. Is the picture above a …. Elliptical Galaxy Irregular Galaxy Spiral Galaxy

5 QUESTIONS (cont.) 2. Name the above picture.. a)Globular cluster b)Open cluster c)Irregular galaxy

5 Questions 3. Who is Edwin Hubble? 4. Where is our Solar System located in the Milky Way? 5. What is a light year? Define and give an example.

Answers 1. a. Elliptical galaxy 2. b. Open Cluster 3. Answers may vary. Edwin Hubble was an Astronomer who discovered there’s more than one galaxy. 4. The solar system is located in the outer arms of a spiral galaxy. 5. A light year is the distance light travels in one year. Ex: 28,000 light years.

Bibliography uestion19.html uestion19.html of-galaxies.html of-galaxies.html

Bibliography (cont.) e.html e.html /Sputnik57/chronology.html /Sputnik57/chronology.html sun/ sun/ BC Science 9 textbook and Workbook THANK YOU!