Since the transverse Doppler effect is one of the main novel predictions of the special theory of relativity, the detection and precise quantification of this effect has been an important goal of experiments attempting to validate special relativity.
Streetlights in the skiing resort Kastelruth in South Tyrol. Medical research on the effects of excessive light on the human body suggests that a variety of adverse health effects may be caused by light pollution or excessive light exposure, and some lighting design textbooks  use human health as an explicit criterion for proper interior lighting.
Health effects of over-illumination or improper spectral composition of light may include: Seoul, which had the highest levels of light pollution, had This suggested a high correlation between ALAN and the prevalence of breast cancer.
It was also found that there was no correlation between other types of cancer such as cervical or lung cancer and ALAN levels. Even if these effects are relatively small from night to night, continuous chronic circadian, sleep and hormonal disruption may have longer-term health risks".
News about the decision emphasized glare as a public health hazard leading to unsafe driving conditions. Especially in the elderly, glare produces loss of contrast, obscuring night vision. Ecological light pollution When artificial light affects organisms and ecosystems it is called ecological light pollution.
While light at night can be beneficial, neutral, or damaging for individual speciesits presence invariably disturbs ecosystems. For example, some species of spiders avoid lit areas, while other species are happy to build their spider web directly on a lamp post.
Since lamp posts attract many flying insects, the spiders that don't mind light gain an advantage over the spiders that avoid it. This is a simple example of the way in which species frequencies and food webs can be disturbed by the introduction of light at night.
Light pollution poses a serious threat in particular to nocturnal wildlife, having negative impacts on plant and animal physiology. It can confuse animal navigationalter competitive interactions, change predator-prey relations, and cause physiological harm.
For example, lepidopterists and entomologists have documented that nighttime light may interfere with the ability of moths and other nocturnal insects to navigate. This can lead to species decline of plants that are unable to reproduce, and change an area's longterm ecology.
Lampyridae, Phengodidae and Elateridae are especially interesting study objects for light pollution, once they depend on their own light to reproduce and, consequently, are very sensitive to environmental levels of light.
These nocturnal animals are very susceptible to light and its effects. A study  also suggests deleterious impacts on animals and ecosystems because of perturbation of polarized light or artificial polarization of light even during the day, because direction of natural polarization of sun light and its reflection is a source of information for a lot of animals.
This form of pollution is named polarized light pollution PLP. Unnatural polarized light sources can trigger maladaptive behaviors in polarization-sensitive taxa and alter ecological interactions.
Estimates by the U. Fish and Wildlife Service of the number of birds killed after being attracted to tall towers range from 4 to 5 million per year to an order of magnitude higher. Similar disorientation has also been noted for bird species migrating close to offshore production and drilling facilities.
Studies carried out by Nederlandse Aardolie Maatschappij b. In earlythe lights were installed on the Shell production platform L It is a common misconception that hatchling sea turtles are attracted to the moon. Rather, they find the ocean by moving away from the dark silhouette of dunes and their vegetation, a behavior with which artificial lights interfere.
Introduced light sources during normally dark periods can disrupt levels of melatonin production. Melatonin is a hormone that regulates photoperiodic physiology and behaviour. Some species of frogs and salamanders utilize a light-dependent "compass" to orient their migratory behaviour to breeding sites.
Introduced light can also cause developmental irregularities, such as retinal damage, reduced juvenile growth, premature metamorphosis,  reduced sperm production, and genetic mutation.
It dealt with bats, turtles, the "hidden" harms of LAN, and many other topics. The following is an excerpt from that article, called "Electricity and English songbirds": An English journal has become alarmed at the relation of electricity to songbirds, which it maintains is closer than that of cats and fodder crops.
How many of us, it asks, foresee that electricity may extirpate the songbird? With the exception of the finches, all the English songbirds may be said to be insectivorous, and their diet consists chiefly of vast numbers of very small insects which they collect from the grass and herbs before the dew is dry.
As the electric light is finding its way for street illumination into the country parts of England, these poor winged atoms are slain by thousands at each light every warm summer evening The fear is expressed, that when England is lighted from one end to the other with electricity the song birds will die out from the failure of their food supply.
Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.Reduce the brightness of the light source or the brightness contrast by lighting the surround Brighter isn’t always better.
Excessive levels of brightness and contrast can produce glare, which can result in effects ranging from mild irritation to virtual blindness. Effects of blue light and sleep. While light of any kind can suppress the secretion of melatonin, blue light at night does so more powerfully.
Harvard researchers and their colleagues conducted an experiment comparing the effects of hours of exposure to blue light to exposure to green light of comparable brightness. In , J. Woodland Hastings and Beatrice M. Sweeney tested the ability of different wavelengths of light—corresponding to different colors—to shift the circadian rhythm in the photosynthetic marine dinoflagellate Gonyaulax leslutinsduphoenix.com greatest power to reset the organism’s daily meter lay in the blues, with a precipitous decline into the greens and a modest boost in the reds.
Glare may be direct (from light source) or reflected from an object; Glare may be irritating or disable vision; To eliminate glare, move the light source, observer or object/task; Change the reflectance of the task; Reduce the brightness of the light source or the brightness contrast by lighting the surround; Brighter isn’t always better.
The effect of reduced street lighting on road casualties and crime in England and Wales: controlled interrupted time series analysis. Rebecca Steinbach 1, Chloe Perkins 2, Lisa Tompson 3, This study was able to shed light on the impact of reduced street lighting at night.
The IOL incorporating blue light–filtering technology significantly reduced glare disability and improved the driver’s ability to safely execute a left turn with oncoming traffic in the presence of glare simulating low-angle sun conditions.