scholarly journals Airglow and Aurorae from Dome A, Antarctica

2012 ◽  
Vol 8 (S288) ◽  
pp. 302-303
Author(s):  
Geoff Sims ◽  
Michael C. B. Ashley ◽  
Xiangqun Cui ◽  
Jon R. Everett ◽  
LongLong Feng ◽  
...  
Keyword(s):  
Statistical Analysis ◽  
Spectroscopic Data ◽  
Optical Observations ◽  
Zenith Distance ◽  
Light Pollution ◽  
Artificial Light ◽  
The Sun ◽  
Dome A ◽  
Near Ir ◽  
Nm Range

AbstractDespite the absence of artificial light pollution at Antarctic plateau sites such as Dome A, other factors such as airglow, aurorae and extended periods of twilight have the potential to adversely affect optical observations. We present a statistical analysis of the airglow and aurorae at Dome A using spectroscopic data from Nigel, an optical/near-IR spectrometer operating in the 300–850 nm range. The median auroral contribution to the B, V and R photometric bands is found to be 22.9, 23.4 and 23.0 mag arcsec−2 respectively. We are also able to quantify the amount of annual dark time available as a function of wavelength; on average twilight ends when the Sun reaches a zenith distance of 102.6°.

scholarly journals Study of Illumination Optical System to Control Light Pollution due to Night Lighting

2018 ◽  
Vol 7 (3.34) ◽  
pp. 516
Author(s):  
Kyung Sun Yoo ◽  
Soo Young Lee ◽  
Dong Hoon Hyun1 ◽  
Byoung Jo Jung
Keyword(s):  
Statistical Analysis ◽  
International Organizations ◽  
Optical System ◽  
Outer Surface ◽  
Total Internal Reflection ◽  
Light Pollution ◽  
Artificial Light ◽  
Pollution Problem ◽  
Inner Surface ◽  
Control Light

Background/Objectives: Artificial light has developed with both sides of light pollution. International organizations recognize the seriousness of light pollution and are offering ways to make restrictions light pollution.Methods/Statistical analysis: It padded an additional surface on the back of the lens to convert the light to the House side into a street side. The slope of the additional surface was determined by the angle of the light that emerged from the LED.As a result, it implemented B1 rating of security light on BUG Rating defined by IESNA.Findings: The total internal reflection of the lens was used to control the posterior light. The inner surface was set to totally reflect the light directed toward the house side inside the lens, and the inclination of the outer surface was set so that the light refracted from the outer surface and directed forward when the light exits. As a result of controlling the backlight in this way, the B1 light distribution classified by the BUG rating was implemented. It also made the ratio of light from Street side to House side about 8:2.Improvements/Applications: When applying the expression proposed in this paper to the streetlight optical system, it can complement the light pollution problem.  

scholarly journals Possible Effect of Human-Experimenter on Homeopathic-Like Aqueous Preparations

Water ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1475
Author(s):  
Vladimir Korenbaum ◽  
Tatiana Chernysheva ◽  
Victorya Galay ◽  
Roman Galay ◽  
Alexandr Ustinov ◽  
...  
Keyword(s):  
Statistical Analysis ◽  
Light Scattering ◽  
Dynamic Light Scattering ◽  
Spectral Range ◽  
Placebo Effect ◽  
Measuring Process ◽  
Observer Effect ◽  
Spectral Changes ◽  
Near Ir ◽  
Patient Side

Homeopathy is one of the applications in structured water influencing human health. The objective is to search for the physical basis of homeopathy. This methodology includes a study of absorption in the far IR spectral range, absorption and refraction in THz diapason, dynamic light scattering in the UV–near IR spectral range for the blinded samples of homeopathic-like preparations (HLP) of several parent substances and hidden/apparent controls, and statistical analysis on the significance of distinctions in spectral data between ensembles of HLP of each parent substance and ensembles of hidden/apparent controls. The analysis of nine independent blind studies of aqueous HLP of several parent substances gave statistically significant spectral differences in some preparations with an apparent control (25 comparisons of 35) and a hidden control (11 comparisons of 40). The revealed dominance in the occurrence frequency of differences in any HLP with an apparent control can be treated as involving most of these changes to the samples by the spectral measuring process. This allows interpreting the main mechanism of manifestation of the spectral changes found as the “observer effect”. The therapeutic effect of HLP may be assumed as a combination of the “observer effect” from the physician side and a “placebo effect” from the patient side.

scholarly journals The Effects of Anthropogenic Sound and Artificial Light Exposure on Microbiomes: Ecological and Public Health Implications

2021 ◽  
Author(s):  
Jake M Robinson ◽  
Ross Cameron ◽  
Brenda Parker
Keyword(s):  
Public Health ◽  
Human Health ◽  
Critical Appraisal ◽  
Scientific Literature ◽  
Light Exposure ◽  
Microbial Interactions ◽  
Light Pollution ◽  
Artificial Light ◽  
Future Studies ◽  
Health Implications

Globally, anthropogenic sound and artificial light pollution have increased to alarming levels. Evidence suggests that these can disrupt critical processes that impact ecosystems and human health. However, limited focus has been given to the potential effects of sound and artificial light pollution on microbiomes. Microbial communities are the foundations of our ecosystems. They are essential for human health and provide myriad ecosystem services. Therefore, disruption to microbiomes by anthropogenic sound and artificial light could have important ecological and human health implications. In this mini-review, we provide a critical appraisal of available scientific literature on the effects of anthropogenic sound and light exposure on microorganisms and discuss the potential ecological and human health implications. Our mini-review shows that a limited number of studies have been carried out to investigate the effects of anthropogenic sound and light pollution on microbiomes. However, based on these studies, it is evident that anthropogenic sound and light pollution have the potential to significantly influence ecosystems and human health via microbial interactions. Many of the studies suffered from modest sample sizes, suboptimal experiments designs, and some of the bioinformatics approaches used are now outdated. These factors should be improved in future studies. This is an emerging and severely underexplored area of research that could have important implications for global ecosystems and public health. Finally, we also propose the photo-sonic restoration hypothesis: does restoring natural levels of light and sound help to restore microbiomes and ecosystem stability?

scholarly journals A Systematic Review of Research Investigating the Combined Ecological Impact of Anthropogenic Noise and Artificial Light at Night

2021 ◽  
Vol 9 ◽  
Author(s):  
Wouter Halfwerk ◽  
Paul Jerem
Keyword(s):  
Systematic Review ◽  
Observational Studies ◽  
Ecological Impact ◽  
Experimental Studies ◽  
Ecological Impacts ◽  
Anthropogenic Noise ◽  
Light Pollution ◽  
Artificial Light ◽  
Light At Night ◽  
The Impact

Levels of anthropogenic noise and artificial light at night (ALAN) are rapidly rising on a global scale. Both sensory pollutants are well known to affect animal behavior and physiology, which can lead to substantial ecological impacts. Most studies on noise or light pollution to date have focused on single stressor impacts, studying both pollutants in isolation despite their high spatial and temporal co-occurrence. However, few studies have addressed their combined impact, known as multisensory pollution, with the specific aim to assess whether the interaction between noise and light pollution leads to predictable, additive effects, or less predictable, synergistic or antagonistic effects. We carried out a systematic review of research investigating multisensory pollution and found 28 studies that simultaneously assessed the impact of anthropogenic noise and ALAN on animal function (e.g., behavior, morphology or life-history), physiology (e.g., stress, oxidative, or immune status), or population demography (e.g., abundance or species richness). Only fifteen of these studies specifically tested for possible interactive effects when both sensory pollutants were combined. Four out of eight experimental studies revealed a significant interaction effect, in contrast to only three out seven observational studies. We discuss the benefits and limitations of experimental vs. observational studies addressing multisensory pollution and call for more specific testing of the diverse ways in which noise and light pollution can interact to affect wildlife.

Autonomous Light Assessment Drone for Dark Skies Studies

2020 ◽  
Author(s):  
Matthew N. Goodell ◽  
Takara E. Truong ◽  
Stephanie R. Marston ◽  
Brett J. Smiley ◽  
Elliot R. Befus ◽  
...  
Keyword(s):  
Low Cost ◽  
Field Tests ◽  
Global Scale ◽  
Local Scale ◽  
Light Pollution ◽  
Artificial Light ◽  
Remote Site ◽  
Improper Use ◽  
Initial Results

Abstract The improper use of artificial light causing skyglow is detrimental to many types of wildlife and can potentially cause irregular human sleeping patterns. Studies have been performed to analyze light pollution on a global scale. However, light pollution data on a local scale is not of ten available and the effects at local scale have rarely been studied. Herein, a new custom-designed autonomous light assessment drone (ALAD) is described for evaluating light pollution at local scale. The ALAD is designed and equipped with a sky quality meter (SQM) to measure skyglow and a low-cost illuminance sensor to measure light from artificial sources. Outdoor field tests are performed at a remote site in central Utah and the measured results are validated against data from lightpollution-map.info. The SQM measurements are in agreement with the estimates from the light pollution map, and the initial results demonstrate feasibility of the ALAD for local-scale skyglow assessment.

scholarly journals Emission spectra of light-pollution sources determined from the light-scattering spectrometry of the night sky

2019 ◽  
Vol 491 (4) ◽  
pp. 5586-5594
Author(s):  
Miroslav Kocifaj ◽  
František Kundracik ◽  
Ondrej Bilý
Keyword(s):  
Light Scattering ◽  
Field Experiments ◽  
Spectral Composition ◽  
Emission Spectra ◽  
Pollution Sources ◽  
Light Pollution ◽  
Ambient Atmosphere ◽  
Artificial Light ◽  
Measuring Device ◽  
Night Sky

ABSTRACT The emission spectrum of a light-pollution source is a determining factor for modelling artificial light at night. The spectral composition of skyglow is normally derived from the initial spectra of all artificial light sources contributing to the diffuse illumination of an observation point. However, light scattering in the ambient atmosphere imposes a wavelength-specific distortion on the optical signals captured by the measuring device. The nature of the emission, the spectra and the light-scattering phenomena not only control the spectral properties of the ground-reaching radiation, but also provide a unique tool for remote diagnosis and even identification of the emission spectra of the light-polluting sources. This is because the information contained in the night-sky brightness is preferably measured in directions towards a glowing dome of light over the artificial source of light. We have developed a new method for obtaining the emission spectra using remote terrestrial sensing of the bright patches of sky associated with a source. Field experiments conducted in Vienna and Bratislava have been used to validate the theoretical model and the retrieval method. These experiments demonstrate that the numerical inversion is successful even if the signal-to-noise ratio is small. The method for decoding the emission spectra by the light-scattering spectrometry of a night sky is a unique approach that enables for (i) a systematic characterization of the light-pollution sources over a specific territory, and (ii) a significant improvement in the numerical prediction of skyglow changes that we can expect at observatories.

scholarly journals SPHERE view of the jet and the envelope of RY Tauri

2019 ◽  
Vol 628 ◽  
pp. A68 ◽  
Author(s):  
A. Garufi ◽  
L. Podio ◽  
F. Bacciotti ◽  
S. Antoniucci ◽  
A. Boccaletti ◽  
...  
Keyword(s):  
Polarized Light ◽  
Tangential Velocity ◽  
Intermediate Stage ◽  
Protoplanetary Disk ◽  
Optical Observations ◽  
Mass Star ◽  
Intermediate Mass ◽  
Driving Mechanisms ◽  
Near Ir ◽  
Intermediate Mass Stars

Context. Jets are rarely associated with pre-main sequence intermediate-mass stars. This contrasts with the frequent detection of jets in lower mass or younger stars. Optical and near-IR observations of jet-driving sources are often hindered by the presence of a natal envelope. Aims. Jets around partly embedded sources are a useful diagnostic to constrain the geometry of the concealed protoplanetary disk. We intend to clarify how the jet-driving mechanisms are affected by both spatial anisotropies and episodic variations at the (sub-)au scale from the star. Methods. We obtained a rich set of high-contrast VLT/SPHERE observations from 0.6 to 2.2 μm of the young intermediate-mass star RY Tau. Given the proximity to the Sun of this source, our images have the highest spatial resolution ever obtained for an atomic jet (down to ~4 au). Results. Optical observations in polarized light show no sign of the protoplanetary disk detected by ALMA. Instead, we observed a diffuse signal resembling a remnant envelope with an outflow cavity. The jet is detected in the Hα, [S II] at 1.03 μm, He I at 1.08 μm, and [Fe II] lines in the 1.25 μm and 1.64 μm. The jet appears to be wiggling and its radial width increasing with the distance is complementary to the shape of the outflow cavity suggesting a strong interaction with jet and envelope. Through the estimated tangential velocity (~100 km s−1), we revealed a possible connection between the launching time of the jet substructures and the stellar activity of RY Tau. Conclusions. RY Tau is at an intermediate stage toward the dispersal of the natal envelope. This source shows episodic increases of mass accretion and ejection similarly to other known intermediate-mass stars. The amount of observed jet wiggle is consistent with the presence of a precessing disk warp or misaligned inner disk that would be induced by an unseen planetary or sub-stellar companion at sub- or few-au scales respectively. The high disk mass of RY Tau and of two other jet-driving intermediate-mass stars, HD 163296 and MWC480, suggests that massive, full disks are more efficient at launching prominent jets.

scholarly journals Pulsars as a galactic population

1979 ◽  
Vol 84 ◽  
pp. 119-123
Author(s):  
Joseph H. Taylor
Keyword(s):  
Carbon Monoxide ◽  
Statistical Analysis ◽  
Supernova Remnants ◽  
Galactic Center ◽  
Hii Regions ◽  
The Sun ◽  
Disk Thickness ◽  
Galactic Population ◽  
The Galaxy

Recent pulsar surveys have increased the number of known pulsars to well over 300, and many of them lie at distances of several kpc or more from the sun. The distribution of pulsars with respect to distance from the galactic center is similar to other population I material such as HII regions, supernova remnants, and carbon monoxide gas, but the disk thickness of the pulsar distribution is rather greater, with <|z|>≈350 pc. Statistical analysis suggests that the total number of active pulsars in the Galaxy is a half million or more, and because kinematic arguments require the active lifetimes of pulsars to be ≲5×106 years, it follows that the birthrate required to maintain the observed population is one pulsar every ∼10 years (or less) in the Galaxy.

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