enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Red-giant branch - Wikipedia

    en.wikipedia.org/wiki/Red-giant_branch

    For stars with a degenerate helium core, there is a limit to this growth in size and luminosity, known as the tip of the red-giant branch, where the core reaches sufficient temperature to begin fusion. All stars that reach this point have an identical helium core mass of almost 0.5 M ☉, and very similar stellar luminosity and temperature ...

  3. Helium flash - Wikipedia

    en.wikipedia.org/wiki/Helium_flash

    A helium flash is a very brief thermal runaway nuclear fusion of large quantities of helium into carbon through the triple-alpha process in the core of low-mass stars (between 0.8 solar masses (M ☉) and 2.0 M ☉ [1]) during their red giant phase. The Sun is predicted to experience a flash 1.2 billion years after it leaves the main sequence.

  4. Stellar evolution - Wikipedia

    en.wikipedia.org/wiki/Stellar_evolution

    In the helium cores of stars in the 0.6 to 2.0 solar mass range, which are largely supported by electron degeneracy pressure, helium fusion will ignite on a timescale of days in a helium flash. In the nondegenerate cores of more massive stars, the ignition of helium fusion occurs relatively slowly with no flash. [ 14 ]

  5. The Dirt of Luck - Wikipedia

    en.wikipedia.org/wiki/The_Dirt_of_Luck

    The Dirt of Luck is the first full-length album from American indie rock band Helium. [ 3 ] [ 4 ] It was released in April 1995 on Matador Records and was produced by Adam Lasus . Recording

  6. Fusion power - Wikipedia

    en.wikipedia.org/wiki/Fusion_power

    The Joint European Torus (JET) magnetic fusion experiment in 1991. Fusion power is a proposed form of power generation that would generate electricity by using heat from nuclear fusion reactions.

  7. Cosmological lithium problem - Wikipedia

    en.wikipedia.org/wiki/Cosmological_lithium_problem

    This contrasts with the observed abundance of isotopes of hydrogen (1 H and 2 H) and helium (3 He and 4 He) that are consistent with predictions. [1] Abundances of the chemical elements in the Solar System. Hydrogen and helium are most common, residuals within the paradigm of the Big Bang. [7]

  8. Hypergolic propellant - Wikipedia

    en.wikipedia.org/wiki/Hypergolic_propellant

    A gas, usually helium, is fed to the propellant tanks under pressure through a series of check and safety valves. The propellants in turn flow through control valves into the combustion chamber; there, their instant contact ignition prevents a mixture of unreacted propellants from accumulating and then igniting in a potentially catastrophic ...

  9. Tip of the red-giant branch - Wikipedia

    en.wikipedia.org/wiki/Tip_of_the_red-giant_branch

    When distant stars at the TRGB are measured in the I-band (in the infrared), their luminosity is somewhat insensitive to their composition of elements heavier than helium (metallicity) or their mass; they are a standard candle with an I-band absolute magnitude of –4.0±0.1. [3] This makes the technique especially useful as a distance indicator.