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  2. Effects of ionizing radiation in spaceflight - Wikipedia

    en.wikipedia.org/wiki/Effects_of_ionizing...

    For instance, a NASA design study for an ambitious large space station envisioned 4 metric tons per square meter of shielding to drop radiation exposure to 2.5 mSv annually (± a factor of 2 uncertainty), less than the tens of millisieverts or more in some populated high natural background radiation areas on Earth, but the sheer mass for that ...

  3. Black-body radiation - Wikipedia

    en.wikipedia.org/wiki/Black-body_radiation

    An almost perfect blackbody spectrum is exhibited by the cosmic microwave background radiation. Hawking radiation is the hypothetical blackbody radiation emitted by black holes, at a temperature that depends on the mass, charge, and spin of the hole. If this prediction is correct, black holes will very gradually shrink and evaporate over time ...

  4. Cosmic microwave background - Wikipedia

    en.wikipedia.org/wiki/Cosmic_microwave_background

    Two other effects which occurred between reionization and our observations of the cosmic microwave background, and which appear to cause anisotropies, are the Sunyaev–Zeldovich effect, where a cloud of high-energy electrons scatters the radiation, transferring some of its energy to the CMB photons, and the Sachs–Wolfe effect, which causes ...

  5. Background radiation - Wikipedia

    en.wikipedia.org/wiki/Background_radiation

    Displayed background gamma radiation level is 9.8 μR/h (0.82 mSv/a) This is very close to the world average background radiation of 0.87 mSv/a from cosmic and terrestrial sources. Cloud chambers used by early researchers first detected cosmic rays and other background radiation. They can be used to visualize the background radiation

  6. Matroshka experiments - Wikipedia

    en.wikipedia.org/wiki/Matroshka_experiments

    Matroshka-1 (MTR-1) was sent to the ISS aboard the Soyuz-U/Progress M1-11 supply vehicle launched from Baikonur Cosmodrome on 24 January 2004, and was placed on the outside of the Russian Zvezda module [2] during a spacewalk during Expedition 8 by Alexander Kaleri and Michael Foale on 15 March 2004, and brought inside during Expedition 11 on 18 August 2005 then the experimental elements were ...

  7. Planck's law - Wikipedia

    en.wikipedia.org/wiki/Planck's_law

    The importance of the Lummer and Kurlbaum cavity radiation source was that it was an experimentally accessible source of black-body radiation, as distinct from radiation from a simply exposed incandescent solid body, which had been the nearest available experimental approximation to black-body radiation over a suitable range of temperatures.

  8. Spacecraft thermal control - Wikipedia

    en.wikipedia.org/wiki/Spacecraft_thermal_control

    The thermal control subsystem can be composed of both passive and active items and works in two ways: Protects the equipment from overheating, either by thermal insulation from external heat fluxes (such as the Sun or the planetary infrared and albedo flux), or by proper heat removal from internal sources (such as the heat emitted by the internal electronic equipment).

  9. Stefan–Boltzmann law - Wikipedia

    en.wikipedia.org/wiki/Stefan–Boltzmann_law

    The Earth has an albedo of 0.3, meaning that 30% of the solar radiation that hits the planet gets scattered back into space without absorption. The effect of albedo on temperature can be approximated by assuming that the energy absorbed is multiplied by 0.7, but that the planet still radiates as a black body (the latter by definition of ...