Click to enlarge the image below to

see global outdoor light pollution.

NASA image acquired April 18 - October 23, 2012 This new image of the Earth at night is a composite assembled from data acquired by the Suomi National Polar-orbiting Partnership (Suomi NPP) satellite over nine days in April 2012 and thirteen days in October 2012. It took 312 orbits and 2.5 terabytes of data to get a clear shot of every parcel of Earth’s land surface and islands. The nighttime view of Earth in visible light was made possible by the “day-night band” of the Visible Infrared Imaging Radiometer Suite. VIIRS detects light in a range of wavelengths from green to near-infrared and uses filtering techniques to observe dim signals such as gas flares, auroras, wildfires, city lights, and reflected moonlight. In this case, auroras, fires, and other stray light have been removed to emphasize the city lights. Named for satellite meteorology pioneer Verner Suomi, NPP flies over any given point on Earth’s surface twice each day at roughly 1:30 a.m. and 1:30 p.m. The spacecraft flies 824 kilometers (512 miles) above the surface in a polar orbit, circling the planet about 14 times a day. Suomi NPP sends its data once per orbit to a ground station in Svalbard, Norway, and continuously to local direct broadcast users distributed around the world. The mission is managed by NASA with operational support from NOAA and its Joint Polar Satellite System, which manages the satellite's ground system. NASA Earth Observatory image by Robert Simmon, using Suomi NPP VIIRS data provided courtesy of Chris Elvidge (NOAA National Geophysical Data Center). Suomi NPP is the result of a partnership between NASA, NOAA, and the Department of Defense. Caption by Mike Carlowicz. Instrument: Suomi NPP - VIIRS Credit: NASA Earth Observatory Click here to view all of the  Earth at Night 2012 images  Click here to  read more  about this image   NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
NASA image acquired April 18 – October 23, 2012
NASA Earth Observatory image by Robert Simmon, using Suomi NPP VIIRS data provided courtesy of Chris Elvidge (NOAA National Geophysical Data Center). Suomi NPP is the result of a partnership between NASA, NOAA, and the Department of Defense. Caption by Mike Carlowicz.Instrument: Suomi NPP – VIIRS Credit: NASA Earth Observatory

IDAVic Good Lighting Award

International Dark-Sky Association Victoria Inc welcomes nominations of high quality lighting installations for its Good Lighting Awards. Nominations can be from people associated with the installation or from its users or from its neighbours.
When considering nominating please note the Principles of Good Lighting given below, appropriate to the type of lighting installation. In some cases nomination can be made even if not all the principles have been adhered to, as long as the installation is clearly better than similar ones nearby.

Click below for more information:

Principles of Good Lighting pdf file 

 

Light Pollution is an unwanted consequence of outdoor lighting and includes such effects as sky glow, light trespass, and glare. An illustration of both useful light and the components of light pollution are illustrated in Figure 1. Sky glow is a brightening of the sky caused by both natural and human-made factors. The key factor of sky glow that contributes to light pollution is outdoor lighting.

Source: Adapted from Institution of Lighting Engineers

Figure 1. Example of useful light and light pollution from a typical pole-mounted outdoor luminaire

Light trespass is light being cast where it is not wanted or needed, such as light from a streetlight or a floodlight that illuminates a neighbor’s bedroom at night making it difficult to sleep.

Glare can be thought of as objectionable brightness. It can be disabling or discomforting. There are several kinds of glare, the worst of which is disability glare, because it causes a loss of visibility from stray light being scattered within the eye. Discomfort glare is the sensation of annoyance or even pain induced by overly bright sources. Think of driving along a dark road when an oncoming car with bright headlights suddenly appears. The sudden bright light can be uncomfortable and make it difficult to see. Discomfort and even disability glare can also be caused by streetlights, parking lot lights, floodlights, signs, sports field lighting, and decorative and landscape lights.

 Fig 2. The street light fitting below is low and has a shield to reduce spill lighting. Location -Ballarat

IMG_5783

Fig 3 below the lights are well spaced and only on one side of the road.

IMG_5782

Street Lights – The truth revealed

People believe that street lights reduce the number of road accidents and crime. But is that really so? Seeing is believing!

Here is a video which will reveal the truth!

 

 

Banner DarkSky Vic v2