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Lithium’s story spans the history of the universe and is one that links to all its largest-scale processes: big bang nucleosyntheses, the evolution of stars, and galactic chemical evolution. Lithium was the only metal produced in the big bang, alongside the gases H and He. Stars destroy both stable isotopes of Li easily, yet we still have Li today, even after generations of stars have come and gone. Ongoing production of Li by galactic cosmic rays and by a limited number of Li-producing nuclear reactions and transport processes in some rare types of stars keeps lithium present in the universe.
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The Origins build-a-MEL: Introducing a scaffold to explore the origins of the universe
The origin of the Universe is something that people have pondered for thousands of years. As evidence has mounted, the Big Bang theory has become the consensus scientific model. Much of this same evidence refutes opposing theories such as the earlier Steady State model. The NGSS for high school includes the nature of and evidence for the Big Bang, providing a rich opportunity to explore—with the help of a scaffold—the connections between evidence and competing models about the origins of the Universe.
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- Award ID(s):
- 2027376
- PAR ID:
- 10282181
- Date Published:
- Journal Name:
- The Earth scientist
- Volume:
- 36
- Issue:
- 3
- ISSN:
- 1045-4772
- Page Range / eLocation ID:
- 7-12
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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