Thirty Theses on Light Pollution, 2017

(I) Light Pollution is pollution.

(II) Light Pollution is among the least-understood and least-recognized forms of pollution.

(III) Most people do not know what Light Pollution is.

(IV) Light Pollution distorts the Earth’s natural night sky.

(V) Light Pollution’s distortion on the Earth’s night sky, by extension, distorts the Earth’s natural environments.

(VI) Science has accumulated sparse evidence of the environmental impacts of Light Pollution.

(VII) The accumulated scientific evidence to-date is insufficient to awaken the general population to the existence of Light Pollution and its impact on Earth’s environments.

(VIII) Light Pollution is a recent phenomenon in human history.

(IX) Light Pollution is artificial.

(X) Moonlight is not Light Pollution, but part of the Earth’s natural environment that evolved over billions of years.

(XI) Humans and most non-nocturnal animals have difficulty sleeping under artificial light, preferring the dark of night.

(XII) Light Pollution directly inhibits terrestrial stargazing and other astronomical pursuits.

(XIII) Light Pollution lessens children’s curiosity about the night sky, stunting their desire to learn and imagine.

(XIV) Light Pollution severs mankind’s prime connection for wondering about the cosmos.

(XV) The intended direction of nearly all artificial night lighting is down.

(XVI) Most artificial light illuminates in all directions (down, up, sides).

(XVII) Artificial light that illuminates outside of its intended range wastes energy.

(XVIII) Artificial light that illuminates outside of its intended range may be an encroachment onto surrounding lands and properties.

(XIX) Light Pollution is caused by artificial illumination of the night sky.

(XX) Light Pollution will never be eliminated completely from civilized locations, but it can be greatly mitigated.

(XXI) Light Pollution can be reduced with no impact to quality of life and security.

(XXII) Light Pollution can be significantly reduced by shielding all outdoor lighting to focus illumination on the intended ground target.

(XXIII) Shielded lights make nighttime visibility easier by reducing harsh bulb glare.

(XXIV) Light Pollution can be significantly reduced through the use of timers and motion sensors.

(XXV) All commercial and home decorative lighting should point downward with bulbs or diodes shielded on their sides.

(XXVI) Most Light Pollution comes from street lights.

(XXVII) Newer LED lights contribute far more to Light Pollution than the older, traditional sodium streetlamps.  This is because newer LED diodes blast light across almost the entire visible light spectrum, whereas the older sodium lamps emitted light at a very narrow yellow band within the visible spectrum.

(XXVIII) Newer LED lights are OK for outdoors but should be low-intensity, shielded, and ideally triggered by motion sensors.

(XXIX) Blue light is the worst light for outdoors because the Earth’s atmosphere absorbs blue spectrum light the easiest.  Think of the daytime blue sky!

(XXX) Images from space of the Earth’s ground illuminated at night were once evidence of progress, but now should be viewed as evidence of our collective ignorance about Light Pollution and not understanding how to lessen its impacts on the Earth’s environments.

I don’t normally concluded my posts with “please share/retweet/reblog/etc.” requests, but if you feel better informed of and aware on the topic of light pollution, please forward this to your friends and neighbors.  Spreading knowledge about light pollution is the best strategy for eventually solving the problem!


Hunting the International Space Station

ISS on June 7th, 2017

During this past week I made an effort to track and photograph the International Space Station.  First, on the night of June 5th, I waited for it with my binoculars at the scheduled time for my location.  It did appear in my sky at the appointed time, going from NNW to E.  It was bright and of course moved quickly.  The binoculars did not reveal any additional details that I could not already see with my eyes alone (in other words, nothing).

Now trusting the Interweb’s timekeeping for the ISS and having a general idea of where to look for it relative to coordinates, two nights later I set up my camera on tripod to take what pictures I could.  Because the ISS is so fast, I had to leave my alt-azimuth tripod knobs loose.  This was not too big a deal, as I was able to typically get three to four pictures with my IR remote before the station moved out of view.

In reading NASA’s recommended camera setup for photographing the ISS, I immediately knew my long 300mm lens was about half their suggestion.  They essentially say you need a nice long telegraphic lens.  Still, I was undeterred.  Of the images I took in those brief three minutes, the above I consider the best.  This is a highly magnified section of the original, taken at f/8, 1/1000 seconds, and ISO 3200.

On Sunday night yesterday, I attempted more pictures during the ISS’s even longer four-minute flyby.  But all of these were either blurry or at a bad angle, as all I got were blobs.

To see something really interesting about the ISS, I recommend checking out Jim R’s cool capture of the ISS transiting the Sun.

Thanking the Planets for Scientific Advancement

If it were not for the planets, where would civilization be today?  For one, I doubt I would have this computer, and the electricity to power it.  The people of this alternative 21st century would be waiting at least several hundred years more for those amenities.

The classical planets of the Sun, Moon, Mercury, Venus, Mars, Jupiter and Saturn are the exceptions in the sky.  (And did you just notice that there are seven of them?  Think of the days of the week.)  There are clouds too, but for our ancestors those were easy to explain as both the chores and whims of the gods.  The stars are fixed, as far as the unaided can see.  But those crazy planets break the rules, making the geocentric universe difficult to explain.

(Uranus was out there too, but likely went unnoticed until Sir William Herschel came along as nothing but an insignificant, dim star, moving too slowly for anyone to appreciate.)

The Sun and Moon are fairly easy as well.  Though they wobble in the sky throughout the year, nothing is perfect, right?  The point being their motions are very easy to predict, day after day, month after month, and year after year.

Then there are the visible planets, the real planets of Mercury, Venus, Mars, Jupiter, and Saturn.  If not for these, there may never have been any questioning of the order of our solar system, or our place in it.  Scientific advancements took off, in the context of the arc of history, once people accepted that the Earth revolved around the Sun.  For if we did not have these planetary exceptions in the sky, would there ever have been the intellectual curiosity to question?

The planets, unlike the “fixed” stars, offer these problems to explaining the geocentric model (i.e. Earth being at the center of the universe):

  • There is a difference in behaviors between the two inner planets and the three outer planets.  Whereas Mars, Jupiter, and Saturn at least appear follow the elliptic path of the Sun, Venus and Mercury are constantly zigging and zagging in proximity to the Sun.  Mercury quickly bounces from dusk to dawn.  Venus sometimes climbs really high in the sky, yet also falls back into Mercury-like behavior.
  • The planets speed up and slow down.
  • Sometimes, the planets start moving in the opposite direction of everything else (retrograde motion).
  • Mars is a very curious case by itself, since at times it will shine as brightly as Venus and at others be dimmer than Saturn.

Copernicus was the first to publish the notion that the planets revolve around the Sun.  Later, Kepler devised his laws of planetary motion, which explain all of the conditions listed above.  Still later, Newton came long, basing his general laws of gravity and motion on Kepler’s earlier work (and Kepler’s laws turned out to be a special case of Newton’s general gravitational laws).  Newton’s work in this and related areas was the genesis of our modern scientific knowledge.

If there were no planets, there would have been no questioning of the Earth’s status relative to the Sun.  If that questioning never happened, we would have never had a true reference as to our place in the universe, making fundamental questions on physics difficult to comprehend.  I don’t doubt that eventually we would have come around to figuring these things out, only that it would have taken far longer if not for the guidance of the planets.

So here’s to you, Mercury, for your quickness.

Here’s to you, Venus, for your brightness.

Here’s to you, Sun, for keeping the lights on when we need them.

Here’s to you, Moon, for all of your cool phases.

Here’s to you, Mars, for being the most famous red beacon in the sky.

Here’s to you, Jupiter, for your steadfastness.

And here’s to you, Saturn, for the delight you reveal through our telescopes.

No, President Trump, the Skies of Detroit and Nebraska Are Not the Same


“And whether a child is born in the urban sprawl of Detroit or the windswept plains of Nebraska, they look up at the same night sky, they fill their heart with the same dreams and they are infused with the breath of life by the same Almighty Creator.”

– Donald Trump’s Inaugural Address, January 20th, 2017

If only this were true, Mr. President.

The night sky in the city of Detroit is far different from the night sky in the state of Nebraska.

The child of the plains will likely have a wonderful view of the universe on clear evenings.  He will wonder, and dream, and imagine.  He will think about his place in the cosmos.  He will ponder both philosophical and spiritual questions about the Almighty Creator.  His ability to see the night sky in its nearly-complete wondrous glory will provide him with opportunities to become a sound and thoughtful adult.

The child of urban sprawl will grow up seeing a far different sky.  Her childhood will be spent under a sickly, orange haze.  She will not look up and wonder, because there will be nothing in her night sky to dream about.  Chances are, the overbearing glare of her neighbor’s porch light or a simmering alley bulb will arrest her attention far more than anything up in the sky.  This is not a place to wonder, or dream, or ponder about life and God.  With the simple absence of a decent night sky comes lost opportunity and inspiration for this child trapped in an urban light prison.

Of course, the city and country skies will never be the same, but the tragedy of light pollution is that so much of it could be mitigated with cognizant planning and effort by all.  We are all victims of this least-understood form of pollution.  Contrary to photographs taken from orbit, it is aesthetically uninteresting.  While scientists are just beginning to document light pollution’s adverse effects, both we and all our living ecosystems depend on the quality of a proper night just as much as the radiance of the Sun at day.