نتایج جستجو برای: dark skies
تعداد نتایج: 76907 فیلتر نتایج به سال:
Skylight polarization provides a significant navigation cue for certain polarization-sensitive animals. However, the precision of the angle of polarization (AOP) of skylight for vehicle orientation is not clear. An evaluation of AOP must be performed before it is utilized. This paper reports an evaluation of AOP of skylight by measuring the skylight polarization patterns of clear and cloudy ski...
Two sky luminance distributions are given for overcast sky above snow-covered terrain, and directional luminous reflectance data are presented which were obtained under these skies. Luminous reflectances computed from Krinov spectral reflectance data for a variety of natural terrains measured under overcast are also included.
Beneath most overcasts, clouds' motions and rapidly changing optical depths complicate mapping their angular distributions of luminance L(v) and visible-wavelength radiance L. Fisheye images of overcast skies taken with a radiometer-calibrated digital camera provide a useful new approach to solving this problem. Maps calculated from time-averaged images of individual overcasts not only show the...
On March 19, 2008 NASA’s Swift satellite discovered one of the brightest gamma-ray bursts ever recorded. With a peak visual magnitude of 5.3, GRB 080319B was dubbed the “naked-eye” gammaray burst, as an observer under dark skies could have seen the burst without the aid of an instrument. Due to the proximity in both time and space to GRB 080319A, prompt emission from GRB 080319B was detected in...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید