Spatially resolved near infrared observations of Enceladus’ tiger stripe eruptions from Cassini VIMS

Abstract. Detection and characterization of aerosols is inherently limited at night due to a lack of sensitivity—information typically provided by visible spectrum observations. The VIIRS Day/Night Band (DNB) onboard the Suomi-NPP satellite is a first-of-its-kind calibrated sensor capable of collecting visible/near-infrared observations during both day and night. Multiple studies have suggested that anthropogenic light emissions such as those from cities and gas flares may be useable as light sources for retrieval of atmospheric properties including cloud and aerosol optical depth. However, their use in this capacity requires proper characterization of their intrinsic variation, which represents a source of retrieval uncertainty. In this study we use 18 months of cloud-cleared VIIRS data collected over five selected geographic domains to assess the stability of anthropogenic light emissions and their response to varied satellite and lunar geometries. Timeseries are developed for each location in each domain for DNB radiance, four infrared channels, and satellite and lunar geometric variables, and spatially-resolved correlation coefficients are computed between DNB radiance and each of the other variables. This analysis finds that while many emissive light sources are too unstable to be used reliably for atmospheric retrievals, some sources exhibit a sufficient stability (relative standard deviation

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Accretion and Outflow Activity in the Earliest Phases of Star-Formation: CO, Sub-mm Continuum, and Near-Infrared Observations

International Astronomical Union Colloquium ◽

10.1017/s0252921100043645 ◽

1997 ◽

Vol 163 ◽

pp. 725-726

Author(s):

K.-W. Hodapp ◽

E. F. Ladd

Keyword(s):

Near Infrared ◽

Spectral Energy Distribution ◽

Far Infrared ◽

Point Sources ◽

Spectral Energy ◽

Infrared Observations ◽

Circumstellar Material ◽

Dense Cores ◽

Wavelength Radiation ◽

Main Component

Stars in the earliest phases of their formation, i.e., those accreting the main component of their final mass, are deeply embedded within dense cores of dust and molecular material. Because of the high line-of-sight extinction and the large amount of circumstellar material, stellar emission is reprocessed by dust into long wavelength radiation, typically in the far-infrared and sub-millimeter bands. Consequently, the youngest sources are strong submillimeter continuum sources, and often undetectable as point sources in the near-infrared and optical. The most deeply embedded of these sources have been labelled “Class 0” sources by André, Ward-Thompson, & Barsony (1994), in an extension of the spectral energy distribution classification scheme first proposed by Adams, Lada, & Shu (1987).

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Comparison of satellite microwave backscattering (ASCAT) and visible/near-infrared reflectances (PARASOL) for the estimation of aeolian aerodynamic roughness length in arid and semi-arid regions

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-5-2933-2012 ◽

2012 ◽

Vol 5 (2) ◽

pp. 2933-2957

Author(s):

C. Prigent ◽

C. Jiménez ◽

J. Catherinot

Keyword(s):

Arid Regions ◽

Near Infrared ◽

Roughness Length ◽

Aerodynamic Roughness Length ◽

Sources Of Information ◽

Transport Models ◽

Dust Transport ◽

Infrared Observations ◽

Aerodynamic Roughness ◽

Semi Arid

Abstract. Previous studies examined the possibility to estimate the aeolian aerodynamic roughness length from satellites, either from visible/near-infrared observations or from microwave backscattering measurements. Here we compare the potential of the two approaches and propose to merge the two sources of information to benefit from their complementary aspects, i.e. the high spatial resolution of the visible/near-infrared (PARASOL part of the A-Train) and the independence from atmospheric contamination of the active microwaves (ASCAT on board MetOp). A global map of the aeolian aerodynamic roughness length at 6 km resolution is derived, for arid and semi-arid regions. It shows very good consistency with the existing information on the properties of these surfaces. The dataset is available to the community, for use in atmospheric dust transport models.

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Spatially resolved pharmacokinetic rate images of ICG using near-infrared optical methods

10.1117/12.647205 ◽

2006 ◽

Cited By ~ 2

Author(s):

Burak Alacam ◽

Birsen Yazici ◽

Xavier Intes ◽

Shoko Nioka ◽

Britton Chance

Keyword(s):

Near Infrared ◽

Optical Methods ◽

Spatially Resolved

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Measuring The Tensile Strain of Wood By Visible And Near-Infrared Spatially Resolved Spectroscopy

10.21203/rs.3.rs-570550/v1 ◽

2021 ◽

Author(s):

Ma Te ◽

Tetsuya Inagaki ◽

Masato Yoshida ◽

Mayumi Ichino ◽

Satoru Tsuchikawa

Keyword(s):

Light Scattering ◽

Prediction Accuracy ◽

Tensile Strain ◽

Near Infrared ◽

Mean Squared Error ◽

Calibration Model ◽

Spatially Resolved ◽

Squared Error ◽

Stiffness Evaluation ◽

Spatially Resolved Spectroscopy

Abstract Wood has various mechanical properties, so stiffness evaluation is critical for quality management. Using conventional strain gauges constantly is high cost, also challenging to measure precious wood materials due to the use of strong adhesive. This study demonstrates the correlation between light scattering changes inside the wood cell walls and tensile strain. A multifiber-based visible-near-infrared (Vis–NIR) spatially resolved spectroscopy (SRS) system was designed to rapidly and conventiently acquire such light scattering changes. For the preliminary experiment, samples with different thicknesses were measured to evaluate the influence of thickness. The differences in Vis–NIR SRS spectral data diminish with an increase in sample thickness, which suggests that the SRS method can successfully measure the whole strain (i.e., surface and inside) of wood samples. Then, for the primary experiment, 18 wood samples with the same thickness (2 mm) were tested to construct a strain calibration model. The prediction accuracy was characterized by a determination coefficient (R2) of 0.86 with a root mean squared error (RMSE) of 297.89 με for five-fold cross-validation; for test validation, The prediction accuracy was characterized by an R2 of 0.82 and an RMSE of 345.44 με.

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Near-infrared observations of the Fornax dwarf galaxy

Astronomy and Astrophysics ◽

10.1051/0004-6361:20066788 ◽

2007 ◽

Vol 467 (3) ◽

pp. 1025-1036 ◽

Cited By ~ 37

Author(s):

M. Gullieuszik ◽

E. V. Held ◽

L. Rizzi ◽

I. Saviane ◽

Y. Momany ◽

...

Keyword(s):

Near Infrared ◽

Dwarf Galaxy ◽

Infrared Observations

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Secondary eclipses of WASP-18b – near-infrared observations with the Anglo-Australian Telescope, the Magellan Clay Telescope and the LCOGT network

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/sty3381 ◽

2018 ◽

Vol 483 (4) ◽

pp. 5110-5122 ◽

Cited By ~ 2

Author(s):

L Kedziora-Chudczer ◽

G Zhou ◽

J Bailey ◽

D D R Bayliss ◽

C G Tinney ◽

...

Keyword(s):

Near Infrared ◽

Infrared Observations

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Unidentified emission features in the R Coronae Borealis star V854 Centauri

Astronomy and Astrophysics ◽

10.1051/0004-6361/201731549 ◽

2018 ◽

Vol 610 ◽

pp. L6 ◽

Cited By ~ 2

Author(s):

L. C. Oostrum ◽

B. B. Ochsendorf ◽

L. Kaper ◽

A. G. G. M. Tielens

Keyword(s):

Near Infrared ◽

Physical Nature ◽

The Other ◽

Large Telescope ◽

Circumstellar Material ◽

Spatially Resolved ◽

Broad Emission ◽

Very Large Telescope ◽

New Feature ◽

Molecular Nature

During its 2012 decline, the R Coronae Borealis star (RCB) V854 Cen was spectroscopically monitored with X-shooter on the ESO Very Large Telescope. The obscured optical and near-infrared spectrum exhibits many narrow and several broad emission features, as previously observed. The envelope is spatially resolved along the slit and allows for a detailed study of the circumstellar material. In this Letter, we report on the properties of a number of unidentified visual emission features (UFs), including the detection of a new feature at 8692 Å. These UFs have been observed in the Red Rectangle (RR), but their chemical and physical nature is still a mystery. The previously known UFs behave similarly in the RR and in V854 Cen, but are not detected in six other observed RCBs. Some hydrogen might be required for the formation of their carrier(s). The λ8692 UF is present in all RCBs. Its carrier is likely of a carbonaceous molecular nature, presumably different from that of the other UFs.

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