Lesson 1 — Engage

Where did everything come from?

Has the universe always been the same?

  • Task:
    • Write an initial claim: How did the universe form and lead to stars and planets?
    • Choose your best idea and put it on your mini whiteboard.

Rumors Routine

  • Move around and share your claim
  • Listen for similarities/differences
  • Norms:
    • Honor all ideas; we will examine scientific evidence next
    • Focus on testable, scientific claims in upcoming lessons

Video: How Many Stars?

  • What surprised you?
  • What does “many stars → many planets” suggest?

Why study origin?

  • Scientists compare galaxies/solar systems by understanding how the universe formed
  • We’ll use evidence to build a scientific model (compatible with many beliefs, focused on testable claims)

Lesson 2 — Explore

Investigating light from other galaxies

  • Phenomenon:
    • Galaxy absorption lines match H/He patterns but are shifted to red
  • Question:
    • Why are lines more redshifted for more distant galaxies?

Models We’ll Use

  • Model 1: Doppler (sound, moving source)
  • Model 2: Piano (pitch ↔ frequency/wavelength)
  • Model 3: Galaxy redshift (light + motion)
  • Model 4: EM spectrum (frequency ↔ color)

See–Think–Wonder (Group)

  • See:
    • Toward observer → waves bunch → higher frequency
    • Away from observer → waves spread → lower frequency
  • Think:
    • Sound behavior helps explain light behavior
  • Wonder:
    • How does motion change perceived color?

Key Observations

  • Sound: Higher pitch = higher frequency = shorter wavelength
  • Light:
    • Moving away → lower frequency, longer wavelength → redder
    • Moving toward → higher frequency, shorter wavelength → bluer
  • Distant galaxies show increasing redshift with distance

Lesson 3 — Explain

Explaining redshift

  • Claim to test:
    • If spectra redshift increases with distance, the universe is expanding

Construct Your Explanation

  • Use wave-model evidence:
    • H/He absorption signatures shift red
    • Redshift magnitude increases with distance
  • Link:
    • Expansion → galaxies recede → light stretches → redshift

Class Consensus Discussion

  • Steps:
    1. Selected groups present claims + reasoning
    2. Peers restate + ask clarifying questions
    3. Table confers → whole-class agreement
  • Focus prompts:
    • How did models serve as evidence?
    • Was energy destroyed or transformed?
    • What are model limitations?

Take Time for These Key Points

  • H/He absorption patterns shift red with distance
  • Longer wavelengths (red) indicate motion away
  • Therefore, the universe is expanding

Summary Task (Exit Ticket)

  • Write a short paragraph:
    • Your explanation for redshift
    • Evidence (models + spectra)
    • One limitation or lingering question

Lesson 4 — Elaborate

If the universe is expanding, what was it like before?

  • Guiding Question:
    • If expanding now, what was it like 13+ billion years ago?

Balloon Model Activity

  • Inflate = expansion
  • Inferences:
    • Earlier universe: smaller, denser, hotter
    • Galaxies closer in the past; at the beginning → clumped

Conservation Principles

  • Energy isn’t created/destroyed; it moves/changes
  • Matter isn’t created/destroyed; it moves/changes
  • Implication:
    • Early H, He, and energy should persist today (possibly transformed)

Test the Big Bang Claim

  • Predict present-day evidence:
    • Cosmic Microwave Background (CMB): cooled, stretched radiation
    • H/He ratios: ~3/4 H and ~1/4 He (primordial nucleosynthesis)
    • Light stretching: visible light shifts to longer wavelengths over time
  • Compare predictions to observations

Read + Analyze

  • Read short text on early universe temperature/pressure
  • Watch: Origins of the Universe (0:00–1:10)
  • Pair work:
    • Make 3–4 testable predictions
    • Match with observed data (CMB maps, elemental abundances)

Consensus (Evidence)

  • Prompts:
    • How did conservation help link evidence to claims?
    • Which evidence most strongly supports Big Bang?
  • Key points:
    • H:He ratio aligns with early-universe formation
    • Stretched waves explain microwave background
    • Evidence supports a small, hot, dense early universe

Lesson 5 — Evaluate

Is life elsewhere probable?

  • Use your origin/formation model:
    • Big universe → many stars → many planets
    • Similar formation processes → similar features across galaxies

Model Earth-like Planets

  • Pair activity:
    • Build a formation/solar system model
    • Consider habitability (star type, orbit, atmosphere, time)
  • Questions:
    • How many opportunities for life?
    • What increases/decreases probability?
  • Annotate peers’ models with:
    • ✔ Resonates
      • Add
    • ? Question relevance
    • Δ Clarify/represent more clearly
  • Revise your model using feedback

Revisiting the Performance Task

  • Individually:
    • Claim: Probability of life elsewhere
    • Evidence:
      • Expansion + scale (stars/planets)
      • Formation processes across galaxies
      • CMB + H/He ratios supporting origin model
    • Address counterpoints/uncertainties

Driving Question Board (Closure)

  • Which questions did we answer?
  • What’s next?
    • Stability of the solar system
    • Extinction and contact: Could intelligent life be rare or short-lived?

Check Your Understanding

  • Why does redshift increase with distance?
  • What does the CMB tell us?
  • Why is the H/He ratio important?
  • How do conservation laws connect past to present?
  • What evidence supports the claim that life elsewhere is probable?

End of Unit — Key Takeaways

  • Universe is expanding (redshift evidence)
  • Early universe was small, hot, dense (CMB + abundances)
  • Big Bang explains present-day observations
  • Similar formation pathways suggest many Earth-like planets may exist

========== LESSON 1 — ENGAGE ==========

========== LESSON 2 — EXPLORE ==========

========== LESSON 3 — EXPLAIN ==========

========== LESSON 4 — ELABORATE ==========

========== LESSON 5 — EVALUATE ==========