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Light pollution: Night being lost in many countries

Started by Rick, Nov 22, 2017, 19:56:56

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Rick

Light pollution: Night being lost in many countries

A study of pictures of Earth by night has revealed that artificial light is growing brighter and more extensive every year.

Between 2012 and 2016, the planet's artificially lit outdoor area grew by more than 2% per year.
Scientists say a "loss of night" in many countries is having negative consequences for "flora, fauna, and human well-being".

A team published the findings in the journal Science Advances

More: http://www.bbc.co.uk/news/science-environment-42059551

Mike

This is completely unnecessary if each country adopted a simple policy on ALL external lighting that forced it to illuminate the area it was designed to and no more. So many lights are badly positioned or shielded resulting in light spilling upwards. The law should dictate that any external light should not be directly visible from an aircraft or satellite. Light pollution is mainly a result of laziness.
We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

ApophisAstros

As it only affects a small % of imagers , don't expect action on this , given everything else that's wrong as well.
Roger
RedCat51,QHYCCD183,Atik460EX,EQ6-R.Tri-Band OSC,BaaderSII1,25" 4.5nm,Ha3.5nm,Oiii3.5nm.

Rick

It affects a lot more than just a few astro-imagers (as the article makes plain), but a lot of the things it affects aren't in a position to complain, and a lot of the people who're affected don't realise how badly they're affected...

NoelC

Africa looks exceptionally good, how about a DSC to the Sahara?
Swapped telescopes for armchair.

The Thing

Quote from: NoelC on Dec 03, 2017, 14:58:44
Africa looks exceptionally good, how about a DSC to the Sahara?

My understanding is the Sahara (big generalisation) has a dusty atmosphere and the seeing is turbulent. Loads of great images are taken in Namibia which has a large desert and not many people, no migrants, slavers, traffickers, jihadis either. I suspect its a bit safer if your taking lots of astro gear. Except for the wildlife which could be interesting.
Nice lion, nice lion...

Carole

I have been to Africa three times, Gambia, Kenya and Egypt.

In the Gambia the sky was disappointingly hazy, Kenya I was in the Masai Mara and don't recall the skies being much to look at there, on the Nile there were too many lights, the only place that was stunningly clear was in the Desert on the way to Abu Simbel, and I could only see the stars through the window of the coach I was on.  Since we had to be escorted by Armed Guard, there was no opportunity of getting out to take a look.

Carole

ApophisAstros

Mostly the best skies are on islands surrounded by water , as in the desert the heat of the day makes viewing hazy as it rises from the land during night , hence any big telescopes that are in desert IE Atacama are way up away from ground level, you actually need Oxygen masks there.
Roger
RedCat51,QHYCCD183,Atik460EX,EQ6-R.Tri-Band OSC,BaaderSII1,25" 4.5nm,Ha3.5nm,Oiii3.5nm.

Rick

The catch with tropical skies is that the air tends to be active, so the seeing isn't often great. In Kenya, for good skies you need to visit higher altitudes. Find yourself somewhere at seven or eight thousand feet above sea level at the right time of year, and the skies will be crystal clear. Trouble is, most times of year are wrong. If it's too hot and dry then the skies are full of dust. If it's the rainy season then the skies are full of cloud. However, one advantage of being close to the equator is that at some point in the year you can see almost every part of the sky...

Islands in the ocean can be good, but to be great they really also need to be high enough.

Rick

Stars could be invisible within 20 years as light pollution brightens night skies

The increased use of light-emitting diodes (LED) and other forms of lighting are now brightening the night sky at a dramatic rate, scientists have found. Indiscriminate use of external lighting, street illumination, advertising, and illuminated sporting venues is now blinding our view of the stars.

In 2016, astronomers reported that the Milky Way was no longer visible to a third of humanity and light pollution has worsened considerably since then. At its current rate most of the major constellations will be indecipherable in 20 years, it is estimated. The loss, culturally and scientifically, will be intense.

More: https://www.theguardian.com/science/2023/may/27/light-pollution-threatens-to-make-stars-invisible-within-20-years


Rick

A lot of modern street lighting is much better at directing light downwards where it is useful than the old sodium and mercury lanterns used to be, but the plethora of consumer-grade flood lights, garden lights and so on are often installed with scant regard for where the light goes, and much more than necessary goes into the skies... :/

Dave A

Rick,

Really shocking that within 20 years many more stars could be invisible to the naked eye

The main issue is large cities and towns with lights on all night which are not needed but kept on as some kind of power symbol- like all of the towers at canary Wharf.  Its only going to get worse-  North Greenwich by the o2 arena has plans for over 40 towers and in 15 years it will mirror Canary Wharf.  The only lights that should be allowed from these towers during the dark should be Red lights on top that alert aircraft.  There must be a law that comes in for all office buildings to have sensor lights- they only come on when people are working inside.