HS-ESS1-3

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Communicate scientific ideas about the way stars, over their life cycle, produce elements.

Clarification statement: Emphasis is on how nucleosynthesis varies as a function of the mass of a star and the stage of its lifetime.

Assessment boundary: Details of the many different nucleosynthesis pathways for stars of differing masses are not assessed.

Reference Tables

Relevant reference tables:

• Generalized Nucleosynthesis in a Massive Star
• H-R Diagram
• Life Cycles of Stars Model

Regents Exam Questions

Released New York State Regents exam questions that assess HS-ESS1-3 are listed here by exam and question cluster. Each link opens the question with its answer key.

Exam	Cluster	Question
August 2026 Earth and Space Sciences Regents	Stars and Elements in the Universe	Question 47
June 2026 Earth and Space Sciences Regents	Stars and Stellar Evolution	Question 5
	The James Webb Space Telescope (JWST)	Question 23
	Planetary Transits	Question 45
January 2026 Earth and Space Sciences Regents	Evidence for the Big Bang Theory	Question 4
	Evidence for the Big Bang Theory	Question 5
August 2025 Earth and Space Sciences Regents	Energy in the Sun	Question 5
June 2025 Earth and Space Sciences Regents	Stars and the Big Bang	Question 17

Vocabulary

Terms from the Earth & Space Science Glossary that come from this standard or from the released exam questions that assess it.

From this standard

• atomic nuclei
• brightness
• compositional elements
• Earth
• electromagnetic energy
• element formation
• elements
• heavier elements
• helium
• hydrogen
• iron
• life cycle
• light spectra
• mass
• mass of a star
• massive stars
• neutron
• nuclear fusion
• nucleosynthesis
• proton
• stars
• supernova
• universe

From released exam questions

• carbon – Aug 2026, June 2026, Jan 2026, Aug 2025, June 2025
• constellation – June 2026
• galaxy – June 2026, Jan 2026
• gamma-ray burst – June 2026
• gravitational collapse – Aug 2025
• latitude – June 2026
• main sequence – Aug 2026, June 2026
• model – June 2026
• multiple-star system – June 2026
• Northern Hemisphere – June 2026
• oxygen – Aug 2026, Jan 2026, Aug 2025, June 2025
• radiation – Aug 2026
• red giant – Aug 2026, June 2026
• solar mass – Aug 2026, June 2025
• stellar evolution – June 2026, Aug 2025
• supergiant – Aug 2026
• surface temperature – Aug 2026
• velocity – Aug 2026

Performance Level Descriptions

Every Regents exam question on HS-ESS1-3 is written to match one of the performance level descriptions (PLDs) below.

Level 1: Given a scientific idea, identify the claim, from those provided, that describes how stars form elements over their life cycle. Aug 2026 · Q47 Aug 2025 · Q5

Level 2: Identify the given scientific idea that describes how different elements are produced by different types of stars over their life cycle. June 2026 · Q45 June 2026 · Q5 June 2026 · Q23 Jan 2026 · Q4 June 2025 · Q17

Level 3: Describe or identify one scientific idea from a source about how stars, over their life cycles, produce different elements depending on their masses or their life cycle. Jan 2026 · Q5

Level 4: Communicate scientific ideas about the way stars, over their life cycles, produce elements.

Level 5: Synthesize valid and reliable scientific information in order to communicate scientific ideas in multiple formats (i.e. orally, graphically, textually, or mathematically) about the way stars, over their life cycles, produce elements.

Notice: PLD levels!

NGSS Dimensions

Performance expectation HS-ESS1-3 was developed using the following elements from the NRC document A Framework for K-12 Science Education:

Science and Engineering Practices

• Obtaining, Evaluating, and Communicating Information
  • Communicate scientific ideas (e.g., about phenomena and/or the process of development and the design and performance of a proposed process or system) in multiple formats (including orally, graphically, textually, and mathematically).

Disciplinary Core Ideas

• ESS1.A: The Universe and Its Stars
  • The study of stars' light spectra and brightness is used to identify compositional elements of stars, their movements, and their distances from Earth.
  • Other than the hydrogen and helium formed at the time of the Big Bang, nuclear fusion within stars produces all atomic nuclei lighter than and including iron, and the process releases electromagnetic energy. Heavier elements are produced when certain massive stars achieve a supernova stage and explode.

Crosscutting Concepts

• Energy and Matter
  • In nuclear processes, atoms are not conserved, but the total number of protons plus neutrons is conserved.

Page contributors: Conrad Richman, Caroline Leonard

Earth and Space Science | HS. Space Systems