Physical Science

• Nucleosynthesis


  ___________ is the process that creates new atomic nuclei from pre-existing nucleons and nuclei.
• Hydrogen


  _______ is a chemical element; it has symbol H and atomic number 1.
• Beta


  ____ particles (β) are high energy, high speed electrons (β-) or positrons (β+) that are ejected from the nucleus by some radionuclides during a form of radioactive decay called beta-decay
• Alpha


  _____ particles (a) are composite particles consisting of two protons and two neutrons tightly bound together. They are emitted from the nucleus of some radionuclides during a form of radioactive decay, called alpha-decay.
• Helium


  ______ is a chemical element; it has symbol He and atomic number 2.
• Sun


  The ___ is the star at the center of the Solar System. It is a massive, hot ball of plasma, inflated and heated by energy produced by nuclear fusion reactions at its core.
• Nucleus


  It is the small, dense region consisting of protons and neutrons at the center of an atom.
• Fusion

  Nuclear ______ is the combination of two or more atomic nuclei to form one or more different nuclei.
• Nuclei


  Nucleus (plural)
• Radiation 


  _________ is energy that comes from a source and travels through space at the speed of light.
• Supernova


  A _________ is a powerful and luminous explosion of a star.
• Gamma


  _____ rays have the smallest wavelengths and the most energy of any wave in the electromagnetic spectrum.
• Atom


  The smallest unit of matter.
• Element


  An _______ is a substance that cannot be broken down into a simpler format.
• Star


  any massive self-luminous celestial body of gas that shines by radiation derived from its internal energy sources.
• Fission


  occurs when a neutron slams into a larger atom, forcing it to excite and split into two smaller atoms
• Protostar


  A _________ is a very young star that is still gathering mass from its parent molecular cloud.
• Stable


  It is the ability of an object to maintain its balance after being disturbed.
• 1. Big Bang Nucleosynthesis (Primordial)
  2. Stellar Nucleosynthesis


  Two phases in the origin of light elements.
• Nucleosynthesis 


  the process that creates new atomic nucleus from pre-existing nucleons, which is protons and neutrons.
• Big Bang Theory 


  The theory states that the universe developed 13.7 billion years ago from a very small, extremely dense, and hot state that expanded rapidly.
• Big Bang Nucleosynthesis

  Protons and neutrons combined together and formed light elements, such as Hydrogen, Helium, Beryllium, and Lithium.
• Nuclear Fusion


  a process by which neutron and protons combine together to form a new atom.
• Stellar Nucleosynthesis

  The formation of heavy elements by the fusion of lighter nuclei in the interior of stars.
• Star Formation Theory (Evolution of Star)


  The _______________ proposes that stars form due to the collapse of the dense regions of a molecular cloud. As the cloud collapses, the fragments contract to form a stellar core called protostar.
• Main Sequence Stars

  Description: The most stable and longest phase of a star's life. Characteristics: • Fusing hydrogen into helium in their core. • Stable size and luminosity determined by mass. • Examples: Our Sun, Proxima Centauri, Sirius A
• Giants


  Description: A general term for stars that have exhausted their core hydrogen and transitioned to burning other elements. Characteristics: • Expanded outer layers, cooler surface temperature than main sequence stars. • Can be further classified as: • Red giants: Lower-mass stars (0.4 - 10 solar masses), typically red in color. • Blue giants: Higher-mass stars (10 - 25 solar masses), hotter and bluer than red giants.
• Red Giants


  Description: Specifically refers to giants formed from lower-mass stars (0.4 - 10 solar masses). Characteristics: • Fusing hydrogen in a shell around a helium core. • Cool surface temperature (around 3,000 - 5,000 K), hence the red color. • Example: Arcturus.
• White Dwarfs


  Description: The remnants of dead stars after they have shed their outer layers during the giant phase. Characteristics: • Extremely dense (comparable to the mass of our Sun packed into the size of Earth). • Very hot (around 10,000 - 100,000 K) despite faint luminosity due to small size. • Slowly cool down over billions of years. • Example: Sirius B.
• The discovery of the interstellar medium of gas and dust during the early part of the 20th century provided a crucial piece of evidence to support the star formation theory.

  Other pieces of evidence come from the study of different stages of formation happening in different areas in space and piecing them together to form a clearer picture.
• Infrared Radiation (IR)


  Energy in the form of Infrared Radiation (IR) is detected from different stages of star formation.
• Extinction 


  __________ in astronomy means the absorption and scattering of electromagnetic radiation by gases and dust particles between an emitting astronomical object and an observer.
• 1. Proton-Proton Chain Reaction 2. CNO (Carbon, Nitrogen, Oxygen) Cycle 3. Tri Alpha Process 4. Alpha Ladder Process

  Nuclear Processes
• Proton-Proton Chain Reaction 


  Involves the fusion of proton (Hydrogen) to form Helium.
• CNO (Carbon, Nitrogen, Oxygen) Cycle


  The stars on the Main Sequence fuse hydrogen into helium via six stage sequence of reactions.
• Tri Alpha Process


  Is the fusion of three alpha particles (4He) to form a carbon atom (12C).
• Alpha Ladder Process


  Alpha particle fusion happens at its core and creates more heavy elements until Iron is formed.
• Proton-Proton Chain Reaction 


  From proton to form Helium
• CNO (Carbon, Nitrogen, Oxygen) Cycle


  proton with Carbon, Nitrogen, and Oxygen to form Helium
• Tri Alpha Process

  3 Helium to form Carbon