After a few months of inactivity I’ve developed an idea that will keep me busy blogging. It’s been cloudy for so much of the summer so I haven’t been able to do much observing. My attention, therefore, has turned to other activities related to astronomy that I can pursue when the weather is not ideal for observing. If you’ve read any of my previous articles on this site you’ve probably read about light pollution. Maybe you’ve heard of it elsewhere or perhaps you’ve never even considered the possibility of light being a pollutant. While electric lighting is a marvel of the industrial age and a wonderful aide to modern life it also, like many good things, has a darker side.
From the beginning of life on Earth approximately 4 billion years ago all of Earth’s creature, including humans, have lived in an unending cycle of light and dark. Bright sun-drenched days give way to the darkness of night and the majesty of a star-strewn sky with its backbone the Milky Way arching across from horizon to horizon. Life has evolved according to that cycle and it has flourished. It wasn’t until just over 100 years ago that we began introducing large quantities of artificial light into the environment. This artificial light disrupts the light-dark cycle (also known as the circadian clock) that life has depended on for billions of years. It has endangered species like insects, turtle, hundreds of species of birds, and all manner of nocturnal creatures. Artificial light is also a known contributor to many human diseases such as obesity, insomnia, diabetes, and hormonal cancers. Besides the biological effects of artificial light, it is also a massive waste of energy. Every year in the United States alone, poorly designed or over-used light that shines up into the sky wastes $2.2 billion!
Last, but certainly not least, artificial light has destroyed the night sky that humans have loved for thousands of years. When the lights from un-shielded fixtures shine up into the sky the light scatters when it hits particles in the air. The result is called skyglow. You can clearly see the effects of skyglow when you look towards a city or town at night from a distance. The yellow, orange, or pink glow in the sky is the sum of all the light from all the street lights, parking lot lights, stadium lights, residential lights, etc…and their light scattered in the air. The dome of light obliterates all but the brightest stars and the Milky Way is a thing of the past. Depending on the size of the city, skyglow is noticeable from as far as 100 miles away as a dome on the horizon.
Light pollution has severe negative consequences on my pursuit of my hobby of astronomy as I have to drive considerably far from my home to view under dark enough skies. I currently drive 33 miles from my home in north Baltimore to reach my observing site in Fawn Grove, PA and even there the effects of light pollution are quite pronounced and the Milky Way is barely visible on clear, moonless nights. To reach a location almost totally unaffected by light pollution I’d have to drive five hours north to Cherry Springs State Park near Coudersport, PA.
What I’ve decided to do over the next couple months (or however long it takes) is to compile a photo essay of sorts that chronicles the effects of light pollution throughout the Maryland and Pennsylvania area. My goal is to photograph constellations, horizons, skylines, and light fixtures everywhere to make known to my readers the harmful effects light pollution has on the night sky and astronomy. I will visit many locations throughout Maryland from the Inner Harbor in Baltimore, to a swamp on Maryland’s Eastern Shore, to rural York County, PA, an international dark sky park, and many places in between. I hope that this project will open some eyes and convince people of the reality of light pollution and the truth that it is something that we CAN fix.
In the United States today, eight out of ten people will never see the Milky Way in their lifetime because of light pollution. It doesn’t have to be that way though. Through public education and teamwork with local governments we can reverse the harmful effects of light pollution and preserve the night sky and its splendor for future generations.
Spring is finally in full swing and if you’re like me observing season is about to kick off again. I hate observing in the cold so when April rolls around it’s usually an indicator that better nights are coming…unless you live on the East Coast where it’s been unseasonably cold and cloudy for the last month. April is also exciting because it is Global Astronomy Month. Each year since 2009 Astronomer Without Borders has designated April as Global Astronomy Month to raise awareness for the study of astronomy both professionally and amateur. In my opinion, the biggest part of GAM is International Dark Sky Week. Beginning tomorrow April 5 and continuing through April 11, Astronomers Without Borders and the International Dark Sky Association are teaming up to raise awareness of the issue of light pollution. If you’ve read this blog before you’re probably familiar with the light pollution as I write about it quite frequently.
Because of light pollution, the artificial brightening of the night sky, less than a third of Earth’s population lives under natural, starry skies. Fifty percent of Americans and 75% of Europeans have to travel at least an hour from their homes to see a natural star-filled sky unaffected by light pollution. From my home in Maryland I have to travel 4.5 hours to reach the only truly dark sky spot around, Cherry Springs State Park in Potter County, Pennsylvania. I am willing to make this pilgrimage once or twice a year but there should be somewhere closer to observe from that has a quality dark sky. The reality is, however, that these places are slowly dwindling in number. Artificial light, the scourge of the night sky, is slowly but surely conquering the beauty of the natural night sky.
Light pollution comes from poorly designed artificial light sources we use at night. Most of these light sources are from street lights that are unshielded so that light escapes upwards into the air which causes the light particles to scatter and create that familiar sky glow effect. Other problems are that we often use wattage that is too high for the task we’re trying to accomplish. If you’re using too bright of a light the light actually reflects off the ground and bounces back up into the sky to contribute to the sky glow.
You’ve also probably noticed the annoying glare that unshielded lights cause while driving. Glare comes from the bright ball of light generated by a typical drop lens or acorn style street light. See the example below for a typical “glare bomb”. The glare created by these lights can not only be annoying while driving, they can also be dangerous for people with poorer eyesight such as seniors or people with sight disorders. They are also so bright that they can mask important things like road signs and signals along with pedestrians and animals in the road.
Light trespass is also an result of poor lighting design. Light trespass occurs when a light from a neighbor or nearby building shines, or trespasses, on your property. For example, a stray light that shines into your bedroom at night that causes you to get inadequate sleep. To make a long story short, the lighting used should fit the requirements of the task it is trying to accomplish, no more, no less. We all agree that artificial light helps our society. But since when did extravagant over illumination become acceptable. Not only does light pollution affect the night sky, it is also a HUGE money waster! Every year over-illumination in the United States alone costs the same as approximately 2 billion barrels of petroleum and consumes unnecessary fossil fuels that are not replenish-able. Imagine how the cost of a gallon of gas could decrease if we didn’t over-illuminate our homes, businesses, and roads!
Fortunately, the solution for light pollution is relatively simple. Taking the time to assess your lighting needs and using the proper wattage and shielded fixtures will go a long way in reducing the amount of artificial light we send up into the night sky. Using shielded fixtures ensures that the light only goes where it is needed: the ground. This also allows for a lower watt bulb to be used and that in turn reduces the amount of light reflected back off the ground. Motion sensor are also useful to turn the light on only when there is movement.
Talking to neighbors about their lighting in a polite but concerned way is a great way to introduce the topic to them. Writing to legislators can be effective as well. There have been a number of municipalities that have incorporated lighting regulations into state, county, or local code in recent years. There is a bill in Maryland that is currently in the General Assembly that would require all new light fixtures purchased by state agencies to be fully shielded. The biggest hurdle we have to overcome is simply making people aware that there is a problem. Many people don’t even think about the light they see at night or how their lights are contributing to the pinkish glow we know all too well. In order to reverse the effects of light pollution we must use word of mouth to let people know that light pollution is real and it is diminishing the beauty of our night sky and wasting money in the process.
If you’d like to learn more about the issue of light pollution please read some of the other posts I’ve written on this blog and visit the International Dark Sky Association’s website www.darksky.org. Together we can put a cap on light pollution and restore the beauty of a star-filled sky!
I love hearing about light pollution in the news and media, especially when the stories are about people, towns, or governments taking action. That’s why when I read an article on guardian.co.uk about a new light pollution law in France I nearly did my version of the Ray Lewis dance! The new law is an attempt to both curb several aspects of light pollution. France’s Minister for Ecology, Sustainable Development and Energy, Delphine Batho, announced the new law yesterday directed towards lighting on non-residential buildings across the country. The new law will make it obligatory for shops and commercial buildings in France to shut off their interior, window, and exterior lighting at night.
The main aspects of the new law are as follows:
- Interior lighting in office buildings must be switched off one hour after the staff leaves the building
- Exterior lighting used for illuminating building facades may be turned on one hour before sunset but must be switched off by 1 a.m.
- Window lighting in commercial buildings must be switched off between 1 a.m. and 7 a.m.
Minister Batho announced the law hopeful for France’s future as a global leader in the fight against light pollution and all its negative effects. According to the non-governmental organization the Agence de l’environnement et de la maîtrise de l’énergie(ADEME), the new law will help France save two terrawatthours of energy each year (1 terrawatt is 1 million megawatts) which is enough to power 750,000 homes in France every year. These energy savings results in a reduction in France’s CO2 output by 250,000 tons each year.
As with almost every light pollution ordinance there are exceptions. Buildings that are tourist attractions year-round are exempt from the new law, as well as Christmas lights, and local holidays and festivals.
Minister Batho is hopeful that the new regulations will not only reduce France’s energy consumption, but also help preserve the nocturnal environment, limit health problems caused by excess light, and of course help improve the quality of the night sky. The law will go into effect on July 1, 2013 so if you’re an astronomer, professional or amateur, in France make sure you wait until after 1 a.m. to set up your telescope for the night! I can only hope this snowballs into bigger and better things for France and all of Europe in regards to fighting light pollution. Well done.Sources: Davies, Katie, The Guardian Online, http://www.guardian.co.uk/world/2013/jan/30/lights-out-france-shops-offices Myels, Robert, Digital Journal http://www.digitaljournal.com/article/342542 de la Baume, Maïa, New York Times http://www.nytimes.com/2013/01/31/world/europe/paris-lights-to-be-dimmed-to-save-energy.html?_r=0 Additional Resources: http://www.lampclick.com “Light Pollution: Effect on Humans and Energy Efficient Solutions“ Astronomers Without Borders Dark Skies Awareness Blog International Dark Sky Association
Last year I had the privilege of writing a short piece about the Dark Sky Festival in Harmony, Florida. I really enjoyed learning about the town of Harmony and the Festival they host every year so when I was asked again this year I jumped at the opportunity. This year’s Dark Sky Festival promises to be the most successful yet.
Once again the town of Harmony, Florida is pleased to present to you the 10th annual Dark Sky Festival! For the last ten years Harmony, a small town southeast of Orlando, has hosted a festival to celebrate the wonder of the Earth’s most beautiful natural resource, the night sky. On the night of February 2nd, 2013 the public is invited to attend a night of celebration and education focused on learning about the night sky and the benefits of living under a night sky free from the effects of excessive artificial lighting. The effects of excessive artificial lighting are scientifically proven to have negative effects on human and wildlife health, to damage the nighttime ecosystem, and of course mask the beauty of the starry night sky.
Harmony, Florida was founded in 2003 by Orlando’s former Humane Society/SPCA director Martha Lentz with the goal of creating a community where humans can live in harmony with nature and the environment. The town was master planned into one of the most unique communities in Florida. One of the goals of the community is to limit its impact on light pollution to preserve a natural view of the night sky. Light pollution is the sum of all the wasted artificial light that is shined into the sky as a result of poorly designed lighting fixtures. This wasted light produces the all too familiar sky glow effect that turns the sky pink near the horizon and washed out overhead. The effects of light pollution can be limited, and even reversed as residents of Harmony know. By taking simple and inexpensive steps to ensure all outdoor lighting fixtures are fully-shielded (meaning no light escapes upward from its source) Harmony has created a very aesthetically pleasing and environmentally friendly lightscape. Furthermore, the lighting regulations created for Harmony are so impressive that the surrounding county which includes parts of Walt Disney World has adopted them as a lighting ordinance.
This year’s Dark Sky Festival promises to be the most successful one yet. Over 5,000 people attended the 2012 Festival and again the town expects to see growth in attendance. Attractions of this year’s Festival include the following:
- Public stargazing with over 50 telescopes
- Speakers from NASA, Seminole State College Planetarium, the International Dark Sky Association, and more
- Two mobile planetariums with presentations and NASA Exhibits
- Variety of kids activities including Mad Science, demos from high school robotics clubs, glow-in-the-dark mini-golf and the Kids Zone
- Music, food, specialty booths, and presentations from scientists
This year’s speakers include International Dark Sky Association’s Executive Director Bob Parks and Jon Cowart, Deputy Partner Manager of NASA’s Commercial Crew Program. If you stick around long enough you might even run into some Star Wars characters from the famous 501st Legion!
Don’t miss this wonderful opportunity to learn more about astronomy and the dark sky movement as well as a chance to explore the universe first-hand through some incredible telescopes! Astronomers from around the state have their telescopes set up for free, public viewing. If you’re completely new to the field of astronomy or a seasoned pro the Dark Sky Festival at Harmony surely has something for everyone. Make sure you stop by the beautiful town of Harmony on Saturday February 2, 2013 to enjoy this rapidly growing annual celebration of the night sky. Festivities begin at dusk at 5 pm and continue until 10 pm.
To learn more about the town of Harmony please visit the town’s website www.harmonyfl.com.
Some weekends are good, some are bad. Some weekends are memorable, some are forgettable. This past weekend was definitely one that I’ll remember for the rest of my life. My dad and I attended the Black Forest Star Party at Cherry Springs State Park this past weekend and it was incredible! Living my entire life under the heavily light polluted skies of the Baltimore/Washington metropolitan area has severely limited my ability to get to a dark sky, and when I say dark I really mean just dark enough that a trace amount of the Milky Way is visible directly overhead. I have to drive about 30 miles from my home in the suburbs in northeastern Baltimore County to reach my dark sky site where I do my observing and even then, there are still significant light pollution domes on the horizon that can extend up to 10 or 15°. It’s not very inspiring to see Sagittarius and the galactic core sink into a haze of bright blue and grey during your observing session but it’s the best I’ve got around home.
Cherry Springs, on the other hand, is simply magnificent! It is located in the middle of a massive state forest in Potter County, PA. There is literally nothing in any direction for at least 20 miles. There is hardly any light pollution evident and only towards the north that extends but a few degrees above the horizon. The starlight is crystal clear with the altitude close to 2,5oo feet and less atmospheric turbulence. Then there’s the Milky Way! The central spiral containing the galactic core extends in milky white beauty up from the horizon in the south-southwest after sunset all the way across to Cassiopeia and almost down to Perseus and Auriga. I’ve never in my life seen a sky so beautiful before! It’s truly amazing that for thousands of years of human history that sight was an every night occurrence and now in the last 150 years we’ve almost completely lost it! It really makes me much more appreciative of the work the International Dark Sky Association does to preserve the night sky and it makes me more proud to support their mission as well.
As for the Black Forest Star Party itself, it was a great time. My dad and I arrived late Friday afternoon and hundreds of other amateur astronomers were already there set up with their telescopes and cars and in some cases, RVs and clam shell observatories. The astronomy field was absolutely packed as you can see from the photos I took. This was my first star party so I expected to get a case of telescope envy and sure enough, I did! The first scope that caught my attention was a 25″ Obsession dob…freaking sweet! We began setting up the tent under increasing cloud cover and by the time we had gotten everything set up the rain started. At that point we were totally bummed that the night was a complete wash out so we got in the tent and did some reading before going to bed around 9pm. I was woken by my dad at around 10:30 to him whispering “Come out and look at the sky!” I mumbled back to him, “The clouds are gone?” and I poked my head out of the tent entrance and…WOW! Our tent was facing southwest and looking directly at the Sagittarius-Scorpius border with the Milky Way exactly perpendicular to the horizon. If my jaw could have dropped, it would have fallen straight to the ground. “Alright, let’s get the scope out” were my next words and we spent the next 2 – 2 1/2 hours observing the pristine skyscape. We viewed many of the Messier objects visible in Sagittarius and Lyra, along with M31, the Andromeda galaxy which was an absolutely stunning view! The Veil Nebula was an amazing sight as well, even without a filter. We also observed the Dumbbell and Ring nebulae. Many globular clusters were great views also in the 35mm Panoptic. We finished the night with M45, the Pleiades and Jupiter in my 6mm Radian but the seeing was pretty bad. We both went to bed feeling extremely satisfied with the night even though it started off so terribly with clouds and rain.
Saturday morning was freezing cold. We cooked eggs and pancakes for breakfast and at noon headed off to the first of the lectures on magnetars and pulsars. The second session was pretty interesting. The Penn State team competing for the Google Lunar X Prize team leader talked about the competition and the search for life in the solar system. Lunch followed, then I planned out what we were going to look at that night (I decided to go with a bit of a Messier Marathon, M2-34). At 5pm was the keynote speaker, Dr. Heidi Hammel, the Executive Vice President of the Association of Universities for Research in Astronomy (AURA) and interdisciplinary scientist working on the James Webb Space Telescope, Hubble’s successor. Dr. Hammel was speaking about JWST and all of its capabilities as NASA’s next great observatory. I very much enjoyed her lecture and I’m all the more excited for JWST’s launch in 2018. The raffle for the door prizes was next but we can skip that part because I didn’t win anything 😦
All that was left was to have dinner and get prepared for another glorious night of observing, and it was going to be glorious because the clouds that ruled the day had cleared out completely by the end of the raffle. The first stars, Vega, Deneb, and Altair began to appear to form the Summer Triangle near the zenith about 20 minutes after sunset, followed by an ever-brightening Milky Way. We did our mini Messier marathon which included objects such as the Lagoon Nebula (which my dad spotted with our binoculars), M13, the Hercules globular cluster, Andromeda again, the Wild Duck cluster, and much more. Again, we ended the night by observing Jupiter which was much higher in the sky than Friday night and the view through the Radian was spectacular! The amount of detail on the cloud bands blew me away and we got to watch Io transit Jupiter for a little while before we decided it was too cold and we were too tired to go on any further. All in all, I’d have to say that both nights were absolutely inspiring!
The other awesome part about the weekend was getting to see all the different (and expensive) telescopes other people brought. I mentioned the 25″ Obsession that was near us, but by far the coolest one was right next to us. The guy two spots over had the most amazing telescope of them all. It was a homemade truss tube dobsonian scope made from machined aluminum. He had fabricated and cut all the aluminum parts from the base, to the pivoting cradle, to the truss tubes, and the secondary mirror ring and painted them red. To top it off he had a Ferrari name plate on the base because his son is a huge Ferrari fan. That little addition was absolutely fricking sweet! He also had a partial light shroud with the Ferrari logo on it. By his estimate, he had spent roughly 200 hours designing and building his scope and had just finished it the week before the star party! The quality of the design and all the parts seemed incredible for a homemade scope. My only regret from the weekend is that I didn’t get more pictures of it or a chance to observe with it as he left Saturday evening. The only picture I got of the scope was of him showing it off to Dr. Michael Paul, the Penn State X Prize team leader (who seemed really impressed by it).
I’m extremely glad I got to go to the Black Forest Star Party this year and I will definitely go again next year, hopefully before then as well. If you’re reading this and you’ve never been, get your rear end up there before it gets too freezing cold! Even if you don’t have a telescope or binoculars you can spend an entire night just staring at the beauty of a truly dark sky. Cherry Springs State Park is dedicated astronomy park and is specially outfitted for the study of astronomy both professionally and for amateurs. It is also only the second International Dark Sky Park in the entire world and is given a gold rating which is the highest level of quality of sky. The upkeep and improvement of Cherry Springs’ astronomy program is funded by the Dark Sky Fund. If you’ve enjoyed the benefits of CSSP in the past please consider donating to the fund to keep the park one of the best in the world.
I would highly recommend CSSP and the BFSP to anybody interested in astronomy. Whatever your experience is, this is the place for you to be! The Black Forest Star Party will go down as one of the coolest and most memorable night of my life so far and I can’t wait to go back! For more pictures of the weekend (including some sub-par images of the sky) visit my album on Imgur.com.
Are you an amateur or professional astronomer looking for a great star party to attend? Does the night sky fascinate you or intrigue you? If you’ve ever wondered what’s out there in the universe then on April 14, 2012 you’ll want to be at the Dark Sky Festival in Harmony, Florida! For nine years running the town of Harmony, about 40 minutes south of Orlando, has hosted a Dark Sky Festival to promote awareness of preserving the nighttime sky, our most spectacular of natural resources. Every April the town of Harmony fills with astronomers professional and amateur alike, and tourists who are curious about the night sky.
As humans we are mysteriously drawn to the cosmos as we attempt to find our place in the universe. It is the story of human experience to ask questions of the heavens and seek to relate to it. The people in Harmony are passionate about the oldest science known to man, the study of the heavens. The Dark Sky Festival is Harmony’s annual sharing of their love of astronomy and the night sky with the surrounding area and tourists. Regularly attracting visitors from the Orlando-Walt Disney World area and the Space Coast to the east, Harmony’s Dark Sky Festival draws about 5,000 visitors each year and they are expecting even more this year!
Events for this year’s festival include science exhibits and demonstrations, NASA speakers and exhibits, a mobile planetarium, live music, food and drinks, glow in the dark mini-golf…and of course, stargazing on “Telescope Hill”. Also featuring at this year’s festival will be the documentary film “The City Dark” by filmmaker Ian Cheney focusing on light pollution and its effects on our culture, our bodies, and the environment. I had the privilege of seeing this film in D.C. a couple weeks ago and it is excellent and I would strongly recommend it for anyone interested in astronomy.
This year’s festival will take place on Saturday April 14, 2012 from 6 – 11pm. The Festival is sponsored by several local astronomy clubs as well as the popular Star Walk app for iPhone and iPad and the International Dark Sky Association. All events are free to the public.
If you’re wondering what the sky is like in Harmony I think you’ll be pleasantly surprised! For being only 40 minutes from Orlando and Disney World Harmony’s skies are rated as a class 4 on the Bortle Scale of light pollution. The town of Harmony is master-planned with environmental intelligence as the goal, specifically reducing the town’s impact on light pollution which is caused from wasteful light that escapes from poorly designed light fixtures. Energy efficiency is also highly valued by town residents as they seek to live responsibly towards nature and the night sky. Harmony’s lighting standards are so impressive that the entire county eventually adopted them as a new lighting ordinance. That is quite a feat since Orlando and Walt Disney World are a part of the same county.
If you are or will be in the Orlando area on Saturday April 14th do yourself a favor and visit the Dark Sky Festival in Harmony, FL. If you’re an astronomer and would like to register to set up your telescope on Telescope Hill visit the astronomers section on the festival’s website. For more information visit www.darkskyfestival.com.
If you’ve never looked through a telescope before, come to be amazed at the vast richness of beauty that is the night sky! The 9th annual Dark Sky Festival at Harmony is free to the public and open to people of all ages. It is a celebration of nature and education of cosmic proportions that will surely inspire and amaze you!
If there’s any such thing as a global holiday it should be Earth Hour. Earth Hour is one day each year where governments, businesses, and individuals turn off their lights for one hour. The day is the last Saturday of March and this year it’s March 31st, 2012. The date is picked so that it is close to the equinox so that as much of the Earth is in darkness as possible as the planet turns. The aim of Earth Hour is to raise awareness about global climate change and to send a message to governments of cities and countries across the world. Earth Hour began back in 2008 in Sydney, Australia when over 200,000 people turned off their lights for one hour. The entire city was behind the project and it was a great success. The following year all of Australia participated and Toronto, Canada also joined. Since then, Earth Hour has spread to over 52,000 towns and cities in 135 countries! This year we hope to have the largest participation yet! The date is 3/31/12 and the time is 8:30pm.
While I’m all for saving energy and the environment and all that I’m also intrigued by the other effects of Earth Hour: the skies. Imagine if you will, if everyone in your city turned off their lights and all the buildings went dark for one hour; how dark would the sky be and how much more of the night sky you would be able to see? Especially in a heavily light polluted state like Maryland, the difference could be dramatic if a large number of people and businesses participate! If you’re an astronomer, or if you support Earth Hour in general, PLEASE, PLEASE spread the word! Use Facebook, Twitter, your blog, your friend’s blogs, whatever outlet you have to spread the word please do so! Together we can unite the world for one hour to preserve what has been given to us and to appreciate the beauty of the heavens. For more information on Earth Hour please check out their website at www.earthhour.org.
Have you ever seen a truly dark sky before? Have you gazed up at the night sky and seen the Milk Way in all its dazzling beauty? Have you seen the staggering splendor of the zodiacal light after twilight? Have you seen the magnificent Messier galaxies and clusters with your naked eye on the clearest of nights? If you are younger than 60 and live within 150 miles of a major city, chances are you answered “No” to each of those questions. That is because of the effects of light pollution, specifically skyglow. Skyglow is the unmistakable “glow” visible in a dome shape that seems to hover above and around cities engulfed in the effulgent glow of electricity. It is remarkable how the tiniest amount of skyglow can render invisible a large amount of stars at night leaving the brightest objects illuminated as mere ghosts of their true beauty.
This type of light pollution drives astronomers, professional and amateur alike, insane! It hinders the effectiveness of not only the naked eye, but the most sophisticated telescope, it masks the fierce beauty of the night sky, and hampers the scientific pursuits of the amateur star-watcher.
Aside from its adverse effects on astronomy, light pollution also is a huge energy waster! I touched on this earlier in my post on Dark Skies, but it’s worth mentioning again that over illumination in the United States is responsible for approximately 4-5 million barrels of petroleum per day in energy wasted! Our light-loving lifestyle is highly inefficient and wasteful and is damaging our health and the environment as well. If you are passionate about night sky preservation visit the folks over at the International Dark-Sky Association. They have many resources available to make efficient and night sky-preserving lighting possible.
If you want to know the extent of the light pollution where you live you can obviously just look outside on a clear night. You can also use this chart published by Sky & Telescope Magazine in 2001. The Bortle Dark-Sky Scale ranks the varying levels of dark sky based on the ability to see certain celestial objects and the visible magnitude of those objects. This chart describe the classes of dark sky as outlined by John Bortle. (**Note that this chart is from Wikipedia; I would have linked to it here but as Wikipedia will be blacked out globally tonight to protest the SOPA and PIPA acts in the U.S. I’ve provided here. This graphic belongs to Wikipedia, I do not own this graphic nor have I had anything to do with its creation). Sorry if the chart doesn’t quite fit on the page, here’s a link to the original article in Sky & Telescope.
That being said, go ahead and use this chart to find out which class your home falls in. If it falls in classes 1-4 get out there tonight and do some stargazing! If you’re like me and most likely live in a class 5 or 6, well my binoculars are easy to transport to someplace darker which is quite often the case when I use them. Please feel free to comment on your night sky conditions where you live so we can all come over your house and have a star party! (only if you live in a 4 or above 😉 ) Enjoy!
|Class||Title||Color key||Naked-eyelimiting magnitude||Stellar limiting magnitude (with 12.5″ reflector)||Description|
|1||Excellent dark-sky site||
|7.6–8.0||19 at best||Zodiacal light, gegenschein, zodiacal band visible; M33 direct vision naked-eye object; Scorpius and Sagittarius regions of the Milky Way cast obvious shadows on the ground; airglowis readily visible; Jupiter and Venus affect dark adaptation; surroundings basically invisible.|
|2||Typical truly dark site||
|7.1–7.5||17 at best||Airglow weakly visible near horizon; M33 easily seen with naked eye; highly structured summer Milky Way; distinctly yellowish zodiacal light bright enough to cast shadows at dusk and dawn; clouds only visible as dark holes; surroundings still only barely visible silhouetted against the sky; many Messier globular clusters still distinct naked-eye objects.|
|6.6–7.0||16 at best||Some light pollution evident at the horizon; clouds illuminated near horizon, dark overhead; Milky Way still appears complex; M15, M4, M5, and M22 distinct naked-eye objects; M33 easily visible with averted vision; zodiacal light striking in spring and autumn, color still visible; nearer surroundings vaguely visible.|
|6.1–6.5||15.5 at best||Light pollution domes visible in various directions over the horizon; zodiacal light is still visible, but not even halfway extending to the zenith at dusk or dawn; Milky Way above the horizon still impressive, but lacks most of the finer details; M33 a difficult averted vision object, only visible when higher than 55°; clouds illuminated in the directions of the light sources, but still dark overhead; surroundings clearly visible, even at a distance.|
|5.6–6.0||15 at best||Only hints of zodiacal light are seen on the best nights in autumn and spring; Milky Way is very weak or invisible near the horizon and looks washed out overhead; light sources visible in most, if not all, directions; clouds are noticeably brighter than the sky.|
|6||Bright suburban sky||
|5.1–5.5||14.5 at best||Zodiacal light is invisible; Milky Way only visible near the zenith; sky within 35° from the horizon glows grayish white; clouds anywhere in the sky appear fairly bright; surroundings easily visible; M33 is impossible to see without at least binoculars, M31 is modestly apparent to the unaided eye.|
|7||Suburban/urban transition or Full Moon||
|4.6–5.0||14 at best||Entire sky has a grayish-white hue; strong light sources evident in all directions; Milky Way invisible; M31 and M44 may be glimpsed with the naked eye, but are very indistinct; clouds are brightly lit; even in moderate-sized telescopes the brightest Messier objects are only ghosts of their true selves.At a full moon night the sky is not better than this rating even at the darkest locations with the difference that the sky appears more blue than orangish white at otherwise dark locations.|
|4.1–4.5||13.5 at best||Sky glows white or orange—one can easily read; M31 and M44 are barely glimpsed by an experienced observer on good nights; even with telescope, only bright Messier objects can be detected; stars forming familiar constellation patterns may be weak or completely invisible.|
|4.0 at best||13 at best||Sky is brilliantly lit, with many stars forming constellations invisible and many weaker constellations invisible; aside from Pleiades, no Messier object is visible to the naked eye; only objects to provide fairly pleasant views are the Moon, the planets, and a few of the brightest star clusters.|
Over the past century there has been one major casualty of urbanization and and afterwards urban sprawl: dark skies. The over-illumination of cities, suburbs, and now even rural towns has caused most Americans to completely forget about the night sky. A majority of the people born since 1950 probably have never seen the spiral arm of the Milky Way or the galactic center at night and it is most likely a forgotten memory to those over 70. Many people living in cities are lucky to be able to see Polaris and even Sirius, if anything at all. For those downtown, the sky is a dark purplish-pink color all night long. I live in Perry Hall, MD which is a suburb of Baltimore approximately 10 miles from downtown. My favorite dark sky site so far is in Jarrettsville, MD which is about 25 miles from Baltimore and the pinkish glow from the city is still very much visible in the southwest washing out almost all the stars on the horizon. Astronomers daily feel the pain of light pollution, but so do all citizens in the country, not in their telescopes but in their wallets.
On average each year over-illumination of cities and towns wastes an amount of energy equivalent to that of over 2 million barrels of petroleum! That is mind blowing! Imagine how much cheaper your gas could cost if we didn’t use streetlights that send their light straight up into the sky or if we kept those skyscrapers more dimly lit! Your city or municipality could save a ton of money on energy if they just used it wisely! The worst part about over-illumination is that most of the light pouring from our cities absolutely goes to waste. The light wasted shoots upward into the atmosphere where it creates a haze of unnatural color in the night sky obliterating all but the brightest stars from view and jacking up energy rates and emptying your pockets.
There are many viable solutions out there to reduce the amount of light pollution in our skies. However, since lawmakers and society in general are unwilling to accept an overhaul to the way we light our lives, and overall slow moving, any meaningful change looks unlikely in the near future. It is projected that by 2025 over 75% of the country will not have access to a reasonably dark sky, compared to slightly less than 50% today. Although, compared to Europe we’re slightly ahead of the game. Less than 10% of Europeans have access to a dark sky that is viable for star viewing, let alone astronomy of any sort. It is an extremely sad consequence of the culture we live in today where technology and human achievement come before natural beauty.
Many towns a few cities across the country already use energy and waste efficient lighting on streets, shopping centers, retailers, and homes but in order for any noticeable progress to be made a nationwide effort must be started. It begins with installing waste reducing lights along highways and streets in major cities. Lights that filter the particles straight downward onto the area desired instead of shooting it in all directions. This would allow for less powerful lights to be used since the needed light is focused directly toward its target. People will next complain that such an program would be too costly to implement but in reality prices for efficient lighting have dropped over the years as more people utilize them. Now the price gap is almost negligible. To stay brief, the point is that efficient and environmentally friendly lighting is highly attainable and has great potential to improve and preserve the natural beauty of the night sky.
As is the case for all civic issues, the best thing to do is to contact your lawmakers and let them know where you stand. You can even suggest to them that they propose a piece of legislation in session. If you live in Maryland the legislative session begins on 1/12/12 (this Thursday). You can also visit websites such as http://www.darksky.org to learn more about light pollution and potential solutions. Organizations like the International Dark-Sky Association need all the help they can get so do what you can and take action!
Lighting suppliers such as LampClick.com are also taking steps to educate the public about the effects and solutions of light pollution. Companies such as LampClick that are aware of the problem and willing to offer solutions should be seriously considered when designing outdoor lighting for your home or business.