Implications of temperature-dependent near-IR spectral properties of common minerals and meteorites for remote sensing of asteroids

AbstractThe Normalized Difference Vegetation Index (NDVI), one of the earliest remote sensing analytical products used to simplify the complexities of multi-spectral imagery, is now the most popular index used for vegetation assessment. This popularity and widespread use relate to how an NDVI can be calculated with any multispectral sensor with a visible and a near-IR band. Increasingly low costs and weights of multispectral sensors mean they can be mounted on satellite, aerial, and increasingly—Unmanned Aerial Systems (UAS). While studies have found that the NDVI is effective for expressing vegetation status and quantified vegetation attributes, its widespread use and popularity, especially in UAS applications, carry inherent risks of misuse with end users who received little to no remote sensing education. This article summarizes the progress of NDVI acquisition, highlights the areas of NDVI application, and addresses the critical problems and considerations in using NDVI. Detailed discussion mainly covers three aspects: atmospheric effect, saturation phenomenon, and sensor factors. The use of NDVI can be highly effective as long as its limitations and capabilities are understood. This consideration is particularly important to the UAS user community.

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Porphyrazines with annulated diazepine rings. 5. Near-IR-absorbing tetrakis(6,7-dihydro-1H-1,4-diazepino)porphyrazines and effects of acid solvation on their spectral properties

New Journal of Chemistry ◽

10.1039/d0nj04388e ◽

2020 ◽

Vol 44 (42) ◽

pp. 18362-18371

Author(s):

Ivan A. Skvortsov ◽

Alina M. Fazlyeva ◽

Ilya A. Khodov ◽

Pavel A. Stuzhin

Keyword(s):

Spectral Properties ◽

Spectral Response ◽

Near Ir ◽

Medium Acidity

Novel porphyrazines bearing fused 6,7-dihydro-1H-1,4-diazepine rings were synthesized and their spectral response on the change of medium acidity was demonstrated.

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Regulation of Near-IR Spectral Properties of Individually Dissolved Single-walled Carbon Nanotubes in dsDNA Aqueous Solutions

ECS Meeting Abstracts ◽

10.1149/ma2008-01/14/580 ◽

2008 ◽

Keyword(s):

Carbon Nanotubes ◽

Aqueous Solutions ◽

Spectral Properties ◽

Single Walled Carbon Nanotubes ◽

Single Walled Carbon ◽

Near Ir ◽

Walled Carbon Nanotubes

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Close-range remote sensing of Saturn’s rings during Cassini’s ring-grazing orbits and Grand Finale

Science ◽

10.1126/science.aau1017 ◽

2019 ◽

Vol 364 (6445) ◽

pp. eaau1017 ◽

Cited By ~ 5

Author(s):

Matthew S. Tiscareno ◽

Philip D. Nicholson ◽

Jeffrey N. Cuzzi ◽

Linda J. Spilker ◽

Carl D. Murray ◽

...

Keyword(s):

Remote Sensing ◽

Physical Properties ◽

Optical Depth ◽

Spectral Properties ◽

Dynamical Processes ◽

Ring Structures ◽

Close Range ◽

Saturn’S Rings ◽

F Ring ◽

Saturn's Rings

Saturn’s rings are an accessible exemplar of an astrophysical disk, tracing the Saturn system’s dynamical processes and history. We present close-range remote-sensing observations of the main rings from the Cassini spacecraft. We find detailed sculpting of the rings by embedded masses, and banded texture belts throughout the rings. Saturn-orbiting streams of material impact the F ring. There are fine-scaled correlations among optical depth, spectral properties, and temperature in the B ring, but anticorrelations within strong density waves in the A ring. There is no spectral distinction between plateaux and the rest of the C ring, whereas the region outward of the Keeler gap is spectrally distinct from nearby regions. These results likely indicate that radial stratification of particle physical properties, rather than compositional differences, is responsible for producing these ring structures.

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