LESSON 1: NUCLEAR REACTIONS AND ORIGINS OF ELEMENTS

Ecosystem Components: Includes diamond, water, steam, and nebula.

States of Matter: Different forms of matter.

Nuclear Reactions:

• Fusion: Nuclei combine.

• Fission: Nucleus splits.

Radioactivity: Emission of particles (electrons, protons, neutrons, positrons).

Big Bang Nucleosynthesis:

• Proposed by Alpher, Bethe, and Gamow in 1948.

• Initially claimed all elements formed in the Big Bang, later found incorrect.

Stellar Evolution:

• Supernova: Star explosion creating new elements.

• Neutron Star: Dense remnant of a massive star.

• Pulsar: Rotating neutron star emitting radiation.

• Magnetar: Neutron star with a strong magnetic field.

• White Dwarf: Core left after a star exhausts fuel.

• Black Dwarf: Theoretical cooled remnant of a white dwarf.

• Black Hole: Core collapse into a singularity with extreme gravity.