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  2. Atmospheric optics - Wikipedia

    en.wikipedia.org/wiki/Atmospheric_optics

    Meteorological optics is "that part of atmospheric optics concerned with the study of patterns observable with the naked eye". [2] Nevertheless, the two terms are sometimes used interchangeably. Meteorological optical phenomena, as described in this article, are concerned with how the optical properties of Earth's atmosphere cause a wide range ...

  3. Atmospheric refraction - Wikipedia

    en.wikipedia.org/wiki/Atmospheric_refraction

    Diagram showing displacement of the Sun's image at sunrise and sunset Comparison of inferior and superior mirages due to differing air refractive indices, n. Atmospheric refraction is the deviation of light or other electromagnetic wave from a straight line as it passes through the atmosphere due to the variation in air density as a function of height. [1]

  4. Terrestrial atmospheric lens - Wikipedia

    en.wikipedia.org/wiki/Terrestrial_atmospheric_lens

    In 1998, NASA astrophysicist Yu Wang from the Jet Propulsion Laboratory for the first time proposed to use the Earth as an atmospheric lens. [2] Wang suggests in his paper that: [3] ''If we could build a space telescope using the Earth's atmosphere as an objective lens the aperture of such space telescope would be the diameter of the earth.

  5. Air mass (astronomy) - Wikipedia

    en.wikipedia.org/wiki/Air_mass_(astronomy)

    When atmospheric refraction is considered, ray tracing becomes necessary (Kivalov 2007), and the absolute air mass integral becomes [7] = ⁡ where is the index of refraction of air at the observer's elevation above sea level, is the index of refraction at elevation above sea level, = +, = + is the distance from the center of the Earth to a ...

  6. Optical window - Wikipedia

    en.wikipedia.org/wiki/Optical_window

    The optical atmospheric window is the optical portion of the electromagnetic spectrum that passes through the Earth's atmosphere, excluding its infrared part; [10] although, as mentioned before, the optical spectrum also includes the IR spectrum and thus the optical window could include the infrared window (8 – 14 μm), the latter is ...

  7. Atmosphere of Earth - Wikipedia

    en.wikipedia.org/wiki/Atmosphere_of_Earth

    The troposphere is the lowest layer of Earth's atmosphere. It extends from Earth's surface to an average height of about 12 km (7.5 mi; 39,000 ft), although this altitude varies from about 9 km (5.6 mi; 30,000 ft) at the geographic poles to 17 km (11 mi; 56,000 ft) at the Equator, [17] with some variation due

  8. Optical depth - Wikipedia

    en.wikipedia.org/wiki/Optical_depth

    Spectral optical depth or spectral optical thickness is the natural logarithm of the ratio of incident to transmitted spectral radiant power through a material. [1] Optical depth is dimensionless , and in particular is not a length, though it is a monotonically increasing function of optical path length , and approaches zero as the path length ...

  9. Earth orientation parameters - Wikipedia

    en.wikipedia.org/wiki/Earth_Orientation_Parameters

    Due to the very slow pole motion of the Earth, the Celestial Ephemeris Pole (CEP, or celestial pole) does not stay still on the surface of the Earth.The Celestial Ephemeris Pole is calculated from observation data, and is averaged, so it differs from the instantaneous rotation axis by quasi-diurnal terms, which are as small as under 0.01" (see [6]).