In this lab, you will be learning about galaxies, how they are classified, and all the important details of our galaxy, the Milky Way. Please read through the information below as you fill in your handout. Follow the instructions below to complete the lab activity. You can download a copy of the lab handout here.


What is a galaxy?

A galaxy is simply cluster of billions of stars held together by gravity. There are believed to be somewhere between 100 and 200 billion galaxies in the Universe. Tap on the image to the right to learn about the Hubble Ultra Deep Field, one of the most powerful images captured. With so many galaxies, astronomers needed to come up with a way of classifying, or organizing them for easier study. The easiest way to do so is using a classification system based on galaxy shape. For our purposes, all galaxies can be classified as one of the following three shapes:
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Stacks Image 1624
Stacks Image 1650


Classifying Galaxies

Click on each of the links below to view photos of 12 different galaxies. Please examine each image carefully and classify each as either spiral, elliptical or irregular. Record your classifications in the space provided on the lab handout.
Galaxy #1
Galaxy #2


The Milky Way Galaxy

The Earth, Sun, and the rest of our solar system are found in a spiral galaxy called the Milky Way. The Milky Way is thought to have formed approximately 13 billion years ago, soon after the Universe formed. We (the Earth, Sun, and solar system) are located in one of the spiral arms of the Milky Way, out away from the center (there is a supermassive black hole found in the center of the Milky Way galaxy).

View a diagram of the Milky Way Galaxy.

Complete the Galaxy Classification Lab Regents Questions.