Read the Beforeitsnews.com story here. Advertise at Before It's News here.
Profile image
By Universe Today (Reporter)
Contributor profile | More stories
Story Views
Now:
Last hour:
Last 24 hours:
Total:

Astronomers Measure the Background Brightness of the Night sky Across the World. Canary Islands are the Darkest in the Survey

% of readers think this story is Fact. Add your two cents.


Being able to look up at a clear, dark sky is becoming more and more rare in the rich world.  Authors, artists, and even scientists have started to express concern about what our lack of daily exposure to a dark night time sky might mean for our psyche and our sense of place in the universe.  Now a team has collected photometric data at 44 sites around the world in an attempt to quantify how dark the night sky actually is at different places on the globe. So where was the darkest place surveyed?  The Canary Islands.

It just so happens that the lead researcher on the project, Dr. Miguel Alarcón is from that set of islands off the west coast of Africa. The paper he and his colleagues wrote, soon to be published in The Astronomical Journal, used a series of photometers, confusing called TESS (not to be confused with the Transiting Exoplanet Survey Satellite) to try to get a baseline of how dark the night sky is throughout the world.

Example of a standardized TESS photometer.
Example of a standardized TESS photometer.
Credit: TESS / Stars4all

The team collected 11 million points of data from places as far apart as Namibia, Australia, and the US.   While this did not include some more popular astronomy spots, such as the highlands of Antarctica, it was a good sample of different conditions. As mentioned above, the Canary Islands had the lowest levels of background light of anywhere studied.  Only about 2% of the light in the sky at night comes from artificial light at the Roque de los Muchachos Observatory in Garafia.  

However, there are other, natural sources of light pollution that affect different geographies differently.  The moon and the milky way are standard features of the night sky and certainly contribute to the natural brightness of it.  However, there are other, more variable sources that this study monitored.  These include a glow in the upper atmosphere that is caused by a combination of factors, such as the solar cycle, geographical location, and the time of year.

Example of different types of light sources in the night sky, including the gegenschein effect.
Example of different types of light sources in the night sky, including the gegenschein effect.
Credit: Juan Carlos Casado

Another source is known as the “gegenschein” or the anti-solar point, directly opposite from the sun in the night sky.  This can only be seen in extremely dark places, and the astronomy institute on the Canary Islands (IAC) is one of them.

Just because it has some of the darkest skies does not mean it’s the best place for all observations though.  Other factors, such as atmospheric seeing and temperature fluctuations can cause problems with observations.  The real take away from this research is that if you truly want to see the night sky as our ancestors did, it might be worth a trip to some islands off the coast of Africa.

Vertical panorama showing the night sky over the Canary Islands.
Vertical panorama showing the night sky over the Canary Islands.
Credit: Juan Carlos Casado

Learn More:
IAC – The natural brightness of the night sky
UT – Most light pollution isn’t coming from streetlights
UT – See Light Pollution in Action

Lead Image:
Image of the Roque de los Muchachos Observatory on the Canary Islands (upper part) and the La Silla Observatory in Chile in the lower part. The composition makes the Milky Way appear circular.
Credit: Juan Carlos Casado & Petr Horálek

The post Astronomers Measure the Background Brightness of the Night sky Across the World. Canary Islands are the Darkest in the Survey appeared first on Universe Today.



Source: https://www.universetoday.com/151198/astronomers-measure-the-background-brightness-of-the-night-sky-across-the-world-canary-islands-are-the-darkest-in-the-survey/


Before It’s News® is a community of individuals who report on what’s going on around them, from all around the world.

Anyone can join.
Anyone can contribute.
Anyone can become informed about their world.

"United We Stand" Click Here To Create Your Personal Citizen Journalist Account Today, Be Sure To Invite Your Friends.

Please Help Support BeforeitsNews by trying our Natural Health Products below!


Order by Phone at 888-809-8385 or online at https://mitocopper.com M - F 9am to 5pm EST

Order by Phone at 888-388-7003 or online at https://www.herbanomic.com M - F 9am to 5pm EST

Order by Phone at 888-388-7003 or online at https://www.herbanomics.com M - F 9am to 5pm EST


Humic & Fulvic Trace Minerals Complex - Nature's most important supplement! Vivid Dreams again!

HNEX HydroNano EXtracellular Water - Improve immune system health and reduce inflammation

Ultimate Clinical Potency Curcumin - Natural pain relief, reduce inflammation and so much more.

MitoCopper - Bioavailable Copper destroys pathogens and gives you more energy. (See Blood Video)
Oxy Powder - Natural Colon Cleanser!  Cleans out toxic buildup with oxygen! 
Nascent Iodine - Promotes detoxification, mental focus and thyroid health.
Smart Meter Cover -  Reduces Smart Meter radiation by 96%!  (See Video)

Immusist Beverage Concentrate - Proprietary blend, formulated to reduce inflammation while hydrating and oxygenating the cells.

Report abuse
Loading...

    Comments

    Your Comments
    Question   Razz  Sad   Evil  Exclaim  Smile  Redface  Biggrin  Surprised  Eek   Confused   Cool  LOL   Mad   Twisted  Rolleyes   Wink  Idea  Arrow  Neutral  Cry   Mr. Green

    MOST RECENT
    Load more ...

    SignUp

    Login

    Newsletter

    Email this story
    Email this story

    If you really want to ban this commenter, please write down the reason:

    If you really want to disable all recommended stories, click on OK button. After that, you will be redirect to your options page.