Dark Skies

 

Google reminded me of this photo taken 9 years ago. Not 100% sure where it was taken but bearing in mind it was the middle of January (i.e. winter), I suspect it was the Isle of Wight where Mary's parents lived.

The photo also reminded me that CPRE has been sending out reminders for Star Count 2023. This will take place between the 17th - 24th February. This an excellent opportunity to be part of a citizen science project. It is the same experiment as last year: just step outside your front or back door, find Orion (The Hunter) in the night sky and count the number of stars you can see within Orion. If you sign up you will get more information and reminders. Remember, even if you are not at home you can still participate - indeed it is advantageous to have reports from as many locations as possible to build up a better picture of skyglow in the night sky.

Light pollution has been steadily getting worse and is obliterating our view of the wonderful night sky.

Sourced from BBC and Kyba et al

Kyba et al have a very readable paper published in Science that is summarised nicely on the BBC website. The paper collates international citizen science data from Globe at Night, using the same approach as CPRE's Dark Skies but is more comprehensive. Why not join this citizen science project as well!

You should also read this commentary by Falchi and Bara, which puts the paper by Kyba et al into context. While light pollution is an annoyance for those just looking up at the beauty of the night sky, it is detrimental to the study of astronomy and potentially life-threatening to many species we share this precious earth with, e.g. moths.

Kyba et al report an annual increase in the light pollution of 7-10% over the last 11 years (i.e. a doubling of skyglow every 8 years). A major reason is, of course, the large amounts of artificial light we humans generate, specifically in urban environments.

NASA photo

Many communities are switching to LED lights because of their lower energy consumption - a benefit to your purse/wallet and the global climate. If we thought this might reduce skyglow then we appear to be mistaken. This could be an example of rebound effect. Because LEDs are less energy intensive and cheaper to run, we use them more widely so the overall reduction in energy use is less than predicted from simply assuming a switch from old technology to new technology.