How do stars make different elements?

Answer 1

Though nuclear fusion. The core of a star is composed of hydrogen atoms. These atoms or rather the nucleuses fuse together forming heavier nucleuses like helium, lithium , sodium, iron, carbon etc.

Answer 2

Elements are created inside active stars by nuclear reactions called stellar nucleosynthesis. The mass and type of the star, temperatures within it, and where it is in its life cycle (which fuels are available for fusion) all factor into which elements are created and at what rate.

Our sun, in regions where the temperature is 10-14 million degrees kelvin (MK), predominately produces helium nuclei, or alpha particles (2 protons + 2 neutrons) by combining 4 hydrogen nuclei (each 1 proton) via nuclear fusion. When these gases get very hot, as they do in the sun, the electrons get stripped away leaving them in a positively-charged, ionized state known as plasma. A plasma hydrogen atom (singular proton) can sometimes beta decay into a neutron and positronvia the little-understood weak interaction. The neutron then combines with 2 protons, the first proton forms deuterium(heavy hydrogen isotope) and the second one forms a light isotope of helium called 3He. Two of these guys (2 protons, 1 neutron) can then combine to form an alpha particle and 2 free protons that are available for more reactions. In summary, the new alpha particle has 0.7% less mass than the combined mass of the original 4 protons that it consists of. The missing mass was released as energy.

In regions of our sun hotter than 14 MK, further fusion reactions can occur to produce lithium and beryllium. Above 23 MK, there will form a heavier beryllium isotope and boron. All these are known as proton-proton chain reactions.

CNO reactions also occur in the sun, where isotopes of carbon, nitrogen and oxygen (and fluorine as an intermediate) act as catalysts to facilitate the formation of alpha particles from protons. These catalysts are not formed within the sun, they have to come from the interstellar media (ISM) from which the sun and rest of the solar system formed. Free neutrons can also originate from heavier elements decaying in this debris.

Many other stellar nucleosynthesis reactions (still mostly fusion) can occur in bigger, hotter stars, mostly resulting in the end products carbon, neon, oxygen, magnesium, silicon, sulphur, iron, and nickel. When the fuel and temperature for fusion is finally depleted, some stars possess the conditions which then result in a huge explosion. During this supernova many more elements are created through neutron capture, and this is generally called supernova nucleosynthesis. Thanks to explosions like these, the elements formed by stars were liberated into the ISM where they could collect and form new stars and planets.

Answer 3

The star converts hydrogen to helium, in a process called nuclear fusion. That is how most stars get most of their energy.

The star converts hydrogen to helium, in a process called nuclear fusion. That is how most stars get most of their energy.

The star converts hydrogen to helium, in a process called nuclear fusion. That is how most stars get most of their energy.

The star converts hydrogen to helium, in a process called nuclear fusion. That is how most stars get most of their energy.

Answer 4

The most important reactions in stellar nucleosynthesis:

• Hydrogen fusing:
  • Deuterium burning
  • The proton-proton chain
  • The carbon-nitrogen-oxygen cycle
• Helium burning:
  • The triple-alpha process
  • The alpha process
• Burning of heavier elements:
  • Lithium burning: a process found most commonly in brown dwarfs
  • Carbon-burning process
  • Neon-burning process
  • Oxygen-burning process
  • Silicon-burning process
• Production of elements heavier than iron:
  • Neutron capture:
    • The R-process
    • The S-process
  • Proton capture:
    • The Rp-process
  • Photo-disintegration:
    • The P-process

Elements heavier than Iron and Nickle are only produced in supernova explosions.

Answer 5

This happens in the interior of stars, at very high temperatures and pressures. Under these circumstances, the lighter elements smash together at high speeds (and therefore energies), and there is a certain probability that the atoms fuse together.

Answer 6

Through nuclear fusion.

Through nuclear fusion.

Through nuclear fusion.

Through nuclear fusion.

Answer 7

All the heavier elements. Only hydrogen and helium existed after the Big Bang, and perhaps small amounts of lithium. All others were fused in stars.

Answer 8

Stars are born when huge hydrogen clouds come together. Stars are mainly hydrogen.

Answer 9

The star converts hydrogen to helium, in a process called nuclear fusion. That is how most stars get most of their energy.

Answer 10

Through nuclear fusion.