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The rise in car headlight intensity, coupled with LED glare, and the increased traffic flow in recent years have contributed to my decision to no longer attend the evening meetings of my local astronomy societies. This research suggests that my inability to cope is not solely due to my ageing.
https://zenodo.org/records/15565958
Has anyone else suffered from this change?This recent article in Environmental Pollution Journal on the effects of ALAN on bird gene expression is one more example of similar research findings elsewhere. https://www.sciencedirect.com/science/article/abs/pii/S0269749125009121
There are a lot of bird watchers in the BAA – what are bird charities such as the RSPB saying about the topic?The state of ALAN science report has always been science-driven, reflecting the BAA’s traditions. John Barentine and DSI colleagues have maintained a database of scientific publications that now numbers around 7,000 – that’s incredible! It seems that professional-quality research in this field is increasing exponentially, which is why it’s so challenging to keep track. Approximately 30% of publications are related to ALAN impacts on nature, which should certainly generate public interest. However, recent work on impacts on human health from low-level overnight stray ALAN is also important. I’m glad I have blackout blinds! The fairly neutral stance CfDS took on the human health impacts (between 2014 and 2019) should now be revisited. In my opinion, the 2025 report is worth special attention, and the authors deserve thanks and appreciation.
I should also mention that there are some exceptional amateurs working on ALAN-related research – it’s not all academic stuff.Members interested in space environment issues should be aware of the IAU-CPS group.
https://cps.iau.org/Members may wish to be aware of an organisation concerned with protecting the environment of space. https://www.spaceenvironmentalism.org/home
The charity Buglife has launched a new campaign called Don’t Neglect the Night. Members might be interested in supporting this.
CfDS thanks attendees and event organisers for facilitating and participating in an opinion poll on the Saturday of the Winchester Weekend. The value of the poll was to engage with members, who often had significant knowledge and ideas to share. Visual observers (of Jupiter for example) were seeing several crossings a night but imagers were finding ways around the problem. This phenomenon may be short lived because new technologies may take over. Radio observations can employ algorithms (AI) to filter satellite interference, apparently.
Results from the poll: 42 members thought CfDS should run a campaign to mitigate against the increase in light pollution and radio noise caused by satellite constellations. 5 members thought CfDS should not bother, citing various and valid reasons. Quite a few people expressed that they were fairly neutral on the issue.
My impression from the day is that it is important that we protest against the more harmful side effects of satellite constellations. A new campaign should be collaborative in nature, encouraging best practices from the space industry. However, this should not detract from light pollution campaign efforts, so new members to be sought to work on this.https://uk.pcmag.com/networking/157759/ast-spacemobile-makes-deal-to-curb-its-huge-satellites-astronomy-interference This news story describes plans for 2nd generation Bluebird satellites having an array area of 2400 square feet, compared with the 693 sq. ft. of the first generation version. The article says that AST will curb its reflectivity but has not disclosed how it will do this. It’s not just visual magnitude and radio interference but IR signatures.
I suggest that this version of VIIRS mapping is correctly correlated and validated. https://pmisson.users.earthengine.app/view/trends
It is slightly more difficult to use than the one published by https://www.lightpollutionmap.info/ but is better once the transparency of the layers are adjusted. A useful exercise is to click randomly over the London area and note the great variability in year by year trends depending upon location.
It is very difficult to draw overall conclusions about trends. The consensus within CfDS is that levels of sky brightness are either unchanged or continue to rise in suburban/urban areas, while some rural locations, in reserves for example, are getting darker, which is good news.
There are fundamental flaws with the satellite method of assessment and continuous ground based monitoring using qualified photometry is probably the most believable way of assessing trends. Are any London based observatories monitoring zenith SQM levels on a continuous basis (with offset to miss the Milky Way)? Of the two rural observatories I am familiar with, one is showing no change at zenith but great increase at lower elevations over a long period, while the other is recently starting to record an increase in sky darkness at zenith (good news but more analysis needed). My own SQM observations from a suburban area are just spot checks and so invalid for true trend analysis.The light pollution map website by Jurij Stare is a valuable tool to assess where nearby pockets of darker skies can be found. https://www.lightpollutionmap.info/help.html
A link to the mapping is on the /help page. It uses VIIRS satellite data and users can choose from a variety of overlays starting from about 2012 to recent. There is a SQM option as well. My own zenith SQM-L records correlate well with the map of my area. There are flaws with using satellite data and sometimes a high zenith reading does not necessarily indicate a good site because of the effect of bright nearby LP sources on lower elevations. Lots to explore and the app seems to be good as well.A bit of background for reassurance. None of the other environmental organisations that CfDS are hoping to work would be likely to be considered controversial, other than with the extremist political fringe. Collectively they would number millions of ordinary supporters.
The reality is that getting anywhere with government requires a professional approach (know how) that the current CfDS committee lacks. Clubbing together resources (a manyfold increase) means that the money will be available to present the most compelling arguments, in the right formats, to the right people.
The previous government missed several opportunities to introduce useful anti LP rules through DEFRA. Experiences with officials there have been largely positive but they can only do the their master’s bidding. The new government has already indicated greater willingness to listen during the LGA conference last year. We are more hopeful than before.
We have worked with the ILP for decades (I was a member myself) and helped to write their guidance on LP mitigation. The last article we wrote for the ILP journal was published only a few months before Bob Mizon died. The ILP supported and took part in our aforementioned LGA event. I think CfDS committee member Kerem Asfuroglu, an award winning professional lighting designer, may be a member of the SLL.
In general we seldom worry about festivals because they are limited in duration and we don’t want to be spoil sports. Actually, they can be opportunities to address LP with the public (eg. Lewes Light Festival). Sky beams are a different matter.This interesting research took eight different USA data sources which correlates an interest in astronomy with access to dark skies. It concludes “… increasing access to the starry night sky may also help to promote more equitable opportunities to feel wonder about the universe, which can motivate interest and engagement in science. The present findings thus begin to suggest how light pollution is not only impacting biological and ecological processes, but also human behavior, science education, and society.”
This could be another campaigning point but correlation is not causation. What was the initial spark that got you interested in astronomy? A teacher, an astronomical event, a book, TV? Did you live in a dark sky area at the time? Bob Mizon grew up in London and got hooked by a book. I became interested when seeing the Aurora from the south of New Zealand but took up astronomy as a hobby after reading a Patrick Moore book. I’m a little sceptical about causation and wonder if a survey of amateur astronomers here would be useful.
https://www.washington.edu/news/2024/10/01/qa-uw-researchers-examine-link-between-light-pollution-and-interest-in-astronomy/
https://www.nature.com/articles/s41598-024-69920-4I have many concerns about the unconstrained used of near space for commercial and geopolitical advantage. From an amateur astronomer view, as Paul Leyland says, a few photometric observations could be spoiled but stacked images can still be edited. Using a smartscope recently to observe in real time I noticed that a satellite track quickly dimmed and was almost invisible in the final image.
But if the predictions of a general increase in global sky glow prove correct (see first link below), will it not reduce the contrast achievable by all instruments everywhere? One implication of this is that dark sky reserves could become a bit irrelevant.
When adding up the other potential threats (such as increasing radio noise, human rights impacts on diverse cultures, the risks of a Kessler syndrome event, the potential for military /commercial instability…), I think this is a topic that everyone should be aware of and have a democratic say about.
Are there (enough) BAA members willing to come forward and start a campaign?For more on the Kessler Syndrome see:
https://www.kesslerrebellion.comHere are some recent items of interest to give flavour of satellite proliferation issues. These are mostly about space junk https://www.space.com/space-junk-new-deadly-era-no-one-is-ready
https://pirg.org/edfund/resources/wastex-environmental-harms-of-satellite-internet-mega-constellations/Space junk is a topic that needs attention.
https://newhumanist.org.uk/articles/6295/cleaning-up-the-cosmosHere are a couple more light pollution items from the internet:
https://www.astronomy.com/science/how-to-win-fight-against-light-pollution/
And if you are into podcasts I recommend this one, even if it’s rather long.
https://lightpollutionnews.com/podcast/crap-lighting/If you want to find dark skies here are some websites that may help you https://www.darkskydiscovery.org.uk , https://gostargazing.co.uk and for the overseas traveler http://spacetourismguide.com .
This is a different approach to monitoring lighting.
https://lichter.nachtlicht-buehne.de/#l=12/52.33797/13.06382In case you’ve not seen this important paper on increasing levels of light pollution. https://www.science.org/doi/10.1126/science.abq7781
From the DSI AGM presentation I learned that it is reckoned that LP is doubling every eight years on a worldwide basis.
