Radiative transfer calculations were performed using a range of realistic values for the seawater inherent optical properties, to determine the possible causes of variations in the shape of the NIR reflectance spectrum. 2 down to 1 in our in situ data set, while a constant value of 1.61 had been proposed based on theory in a previous study. The ratio of reflectances at 765 nm and 865 nm, for instance, varied from ca. In both data sets, a flattening of the NIR reflectance spectrum with increasing turbidity was observed. In situ NIR reflectance data were collected in different European estuaries where extremely turbid waters were found. Space-borne ocean reflectance data were collected using 3 different sensors (SeaWiFS, MODIS/Aqua and MERIS) over the Amazon, Mackenzie and Rio de la Plata turbid river plumes during extremely clear atmospheric conditions so that reliable removal of gas and aerosol effects on reflectance could be achieved. In the present study, we show, based on both in situ and remote sensing data, that the shape of the ocean reflectance spectrum in the NIR does vary in turbid to extremely turbid waters. 51, 1167–1179, 2006) that the variability in the shape of the surface ocean reflectance spectrum in the NIR is negligible in turbid waters. It has recently been proposed (Ruddick et al., Limnology and Oceanography. It is now growingly admitted that the NIR represents a potential optical source of unambiguous information about suspended sediments in turbid waters, thence the need for better understanding the NIR optical behaviour of such waters. "Mid-infrared light specializes in detailing where dust is, the stars aren't bright enough at these wavelengths to appear," NASA said.The optical properties of natural waters beyond the visible range, in the near-infrared (NIR, 700–900 nm), have received little attention because they are often assumed to be mostly determined by the large absorption coefficient of pure water, and because of methodological difficulties. Famously flawed, it is 30 years since the Hubble Space Telescope was launched.Hubble 'scope snaps ENORMO SPACE ERECTION: Pillars of Creation 20 years on.A planet, dense as a marshmallow, that would float on water We've seen things you people wouldn't believe.Hubble's cosmic science is mind-blowing, but its soul celebrates something surprising about us.The picture was taken by Webb's Mid-Infrared Instrument (MIRI), which rather than capturing images of near-infrared light focuses on mid-spectrum infrared light, which NASA said is far better at picking up interstellar dust. Unlike the star-filled, color-rich photo of the astronomical marvel NASA published this month taken using JWST's Near-Infrared Camera (NIRCam), the latest image shows the pillars lifeless and gray, with few stars visible through a thick cloak of dust. The James Webb Space Telescope team has released its latest snap of the Pillars of Creation that strikes a perfect eerie, dusty tone for Halloween.
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