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Using meteorological forecasts to predict astronomical ‘seeing’
SPIE Newsroom, 2009The main limitations affecting visible-light and IR astronomy are related to visibility, atmospheric humidity, and spatial resolution. High-resolution imaging is fundamentally limited by optical turbulence (OT) in the atmosphere. OT is induced by dynamical turbulence developing within a stratified temperature field and depends on weather conditions ...
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The Possibility of Compensating Astronomical Seeing
Publications of the Astronomical Society of the Pacific, 1953The severe limitations imposed upon nearly all astronomical observations by "seeing" the effects resulting from passage of light rays through the turbulent atmosphere of the earth are familiar to every observer. With a small instrument the effect may appear largely as a continual shifting and scintillation of the image of a star, but with a large ...
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Astronomers see ashes of the first stars
Science, 2016Primordial clouds show how giant stars forged the heavy elements that fill today's universe.
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World Lines: What future astronomers won't see
New Scientist, 2008We live in the only time when it is possible to see both the universe's beginning and its end, says Lawrence ...
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Measurement of Astronomical Seeing Using Long Exposure Solar Images
Solar Physics, 2019We extend our modified parameter search method (Sridharan, Dashora, and Venkatakrishnan, Solar Phys. 222, 35, 2004) of estimating the Fried parameter ( $r_{0}$ ) from long exposure images to the images ...
Sridharan Rengaswamy +2 more
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On astronomical seeing: The single Schlieren model
Solar Physics, 1969A model of astronomical seeing with particular view to solar observations is developed which assumes the atmospheric disturbances to consist of individual turbulence elements called Schlieren. A quantitative account is given of each image motion, image blurring and scintillation as function of Schlieren properties and telescope parameters.
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Astronomers See a Cosmic Antigravity Force at Work
Science, 1998COSMOLOGYAn international team of astronomers who have used the brightness of distant exploding stars called supernovae to gauge how cosmic expansion has changed over time has reluctantly concluded that space itself appears to be permeated by a repulsive force.
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Removal of Seeing and Instrumental Blur Effects from Astronomical Scanner Observations
Applied Optics, 1974The Phillips-Twomey method for solving simultaneous integral equations is applied to the problem of removing blur effects arising from atmospheric and instrumental sources from astronomical observations made with photoelectric area-scanning instruments.
A E, Clements, B M, Herman
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Astronomical seeing at Maidanak observatory with DIMM
Observatory Operations: Strategies, Processes, and Systems IX, 2022Azimjon Azimov +3 more
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