Mod 2 – Expanding Universe

9th Grade Science: Expanding Universe
Student Packet
Day 1 – Big Bang & Universe Timeline
Activity: Universe Timeline
Directions: Using the strip of paper/string provided, mark and label these events:

• Big Bang
• First Atoms Form
• First Stars Form
• Galaxies Form
• Solar System Forms
• Earth Forms
• Today
  Reflection: Why do scientists use models like timelines to understand the universe?
  Exit Ticket:

1. What is one piece of evidence scientists use to support the Big Bang theory?
   Day 2 – Redshift & Hubble’s Law
   Activity: Spectra Comparison
   Look at the diagrams below. Circle the one that shows a galaxy moving away.
   [Diagram: Black lines shifted toward blue] [Black lines shifted toward red]
   Challenge: If Galaxy A is farther than Galaxy B, which will have a larger redshift? Why?
   Exit Ticket:
2. What is redshift?
3. How does it show that the universe is expanding?
   Day 3 – Cosmic Microwave Background (CMB) Evidence
   Station Activity
4. CMB Map: What does the color variation mean?
5. Element Chart: Why do scientists think hydrogen & helium dominance supports the Big Bang?
6. Redshift Spectra: What pattern do you notice between distance and velocity?
   Exit Ticket:
   Rank the following evidence in order of most convincing (1 = strongest, 3 = weakest). Explain why.
   Redshift of galaxies
   Cosmic Microwave Background radiation
   Element abundance (hydrogen & helium)
   Your Ranking: _ → → Reason: ________________________________
   Day 4 – Expanding Universe Models
   Balloon Model Instructions
7. Draw at least 5 dots on your balloon (representing galaxies).
8. Inflate the balloon halfway and observe what happens.
9. Continue inflating—what happens to the dots?
10. Record your observations: _______________
    Exit Ticket:
11. If every galaxy is moving away from us, does that mean we are at the center of the universe?
    Explain.
    Mini-Project Prompt
    Create a model or short explanation (poster, slide, or 1-minute video) answering:
    ➡ How do we know the universe is expanding?
    Requirements:

• Must include at least 2 pieces of evidence (redshift, CMB, element abundance).
• Be clear enough to teach someone who missed class.
  Rubric (5 points each):
• Accuracy of science
• Clarity of explanation
• At least 2 pieces of evidence used
• Creativity in communication