Cosmic Playground
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Stars

Stellar structure, equations of state, and the internal physics that determine how stars work. Explore the relationship between temperature, pressure, and density inside stars.

3 exhibits
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Suggested sequence

Not mandatory, but this order builds concepts incrementally.

  1. Hydrostatic Equilibrium Explorer 14 min
  2. HR Diagram Inference Lab 14 min
  3. Cluster Census: Sampling Stars from the Initial Mass Function 15 min

Exhibits

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Hydrostatic Equilibrium Explorer

Key idea: This ASTR 201 explorer turns stellar structure into a balancing act: gravity sets the required pressure gradient, pressure scale height tell

This ASTR 201 explorer turns stellar structure into a balancing act: gravity sets the required pressure gradient, pressure scale height tell

experimental Stars 10–20 min ASTR201 math mode
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HR Diagram Inference Lab

Key idea: This ASTR 201 instrument treats the HR diagram as both a measurement-built map and a hidden-variable inference engine, with staged reveals a

This ASTR 201 instrument treats the HR diagram as both a measurement-built map and a hidden-variable inference engine, with staged reveals a

experimental Stars 10–20 min ASTR201
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Key concepts

Learning goals aggregated from all exhibits in this topic.

  • Describe the initial mass function as a distribution, and state that low-mass stars dominate by number.
  • Explain why the most massive star in a cluster varies a lot between clusters of the same size.
  • Read a cluster's age from the main-sequence turnoff.
  • Distinguish a model's output from the range over which the model is valid.
  • Explain hydrostatic equilibrium as a balance between inward gravity and outward pressure support.
  • Use the pressure scale height to connect local gravity to how steeply pressure must change with radius.
  • Apply the ideal gas law to infer why higher gravity or smaller scale height implies a hotter interior.
  • Use the support chain to reason from stellar mass and radius to an order-of-magnitude core temperature.
  • Use observer-space and theorist-space views to interpret stellar populations as measurement-built maps.
  • Infer stellar radius from luminosity and effective temperature with explicit Stefan-Boltzmann reasoning.
  • Infer hidden mass ordering along the main sequence after staged reveal controls are enabled.
  • Connect mass-dependent lifetimes to conceptual stellar-evolution tracks.