LED Residential Streetlight Debut in Dodgeville: Too Bright!

A new bright white LED streetlight made its debut in Dodgeville, Wisconsin on Friday, November 3, 2017, and it isn’t pretty.

The white-light LED streetlight is located at the NE corner of W. Washington St. & N. Johnson St. in Dodgeville.  The illumination level on the ground peaks at 3.15 fc.  An existing orange-light high pressure sodium streetlight at the SW corner of W. Division St. & N. Virginia Terrace peaks at 1.23 fc, which is typical.

Even though the reduction of uplight and near-horizontal light (i.e. “glare”) from this luminaire is a welcome improvement, an illumination level 2.6 times as bright as before is neither welcome nor justified.  Furthermore, lower illumination levels may be acceptable when using white-light LED luminaires in comparison with high pressure sodium (Glamox n.d.).  More research is needed on the effect of spectral composition on both brightness perception and, more importantly, visual acuity at various illuminance levels.

I do not have an instrument to measure the correlated color temperature (CCT) of this luminaire, but visually it looks to me to be around 4000 K, which is too blue.  I will check with the City of Dodgeville and report back here.  The International Dark-Sky Assocation (IDA n.d.) and the American Medical Assocation (AMA 2016) recommend using “warm white” LEDs with a CCT no higher than 3000 K, with 2700 K preferred.

References
AMA (2016), Human and Environmental Effects of Light Emitting Diode (LED) Community Lighting H-135.927.  Retrieved November 5, 2017 from https://policysearch.ama-assn.org/policyfinder/detail/H-135.927?uri=%2FAMADoc%2FHOD-135.927.xml.

Glamox (n.d.), The Glamox Brightness Sensitivity Test. Retrieved November 5, 2017 from http://glamox.com/gmo-recreational/led-brightness.

IDA (n.d.), LED: Why 3000K or Less.  Retrieved November 5, 2017 from http://www.darksky.org/lighting/3k/.

Oesper, D. (January 9, 2017), Avoid Blue-Rich LED Lighting.  http://cosmicreflections.skythisweek.info/2017/01/09/avoid-blue-rich-led-lighting/.

Henry Norris Russell

Today, we celebrate the 140th anniversary of the birth of one of America’s greatest astrophysicists: Henry Norris Russell (1877-1957).  Called the “Dean of American Astronomers”, he is perhaps best remembered for his discovery of the relationship between the luminosity (absolute brightness) of a star and its color.  We call any plot of luminosity vs. color for a group of stars an H-R diagram, named after Russell and Danish astronomer Ejnar Hertzsprung (1873-1967) who independently discovered this relationship.

Russell noticed that cool (relative to other stars) red stars come in two varieties: those that are dim, and others that are very bright.  The only way a cool, red star could be so bright would be if the star were very, very large1.  In this way, Russell discovered that there are red giants and red dwarfs, but no medium-sized red stars.  Further studies by Russell and others led to the use of the H-R diagram as a tool in understanding the life cycles of stars.  Red giants, it turns out, are one of the final stages in the life of an ordinary star (like the Sun, for example).  Red dwarfs are low-mass stars that change very little throughout their lives.

After famously rejecting the revolutionary conclusion (in 1925) by Cecilia Payne-Gaposchkin (1900-1979) establishing that hydrogen is the primary constituent of the Sun and other stars, Henry Russell concluded four years later that Payne-Gaposchkin was correct, and acknowledged her significant contribution.  Moreover, he surmised that the main physical characteristics of stars are determined by just two basic parameters: mass and chemical composition.  This idea is known as the Vogt-Russell theorem, named after Russell and German astronomer Heinrich Vogt (1890-1968), who independently came up with the same idea.

An interesting sidenote.  Early in his stellar career, when he was just 24 years of age, Henry Russell wrote an interesting article published in the May 1902 issue of Popular Astronomy and dated March 24, 1902: “Shadows Cast by Starlight”.  It is a fascinating read—all the more special because it was written at a time (now over 115 years ago) when light pollution had not yet destroyed our nocturnal environment.

1Here we are comparing stars at comparable distances, such as in a star cluster.

Dark Sky Community Prospectus

  1. Rationale
    1. A small community (hereafter referred to as a dark sky community) can thrive without the need for streetlights or any other dusk-to-dawn lighting
    2. A dark sky community would appeal to people who value the night sky and a natural nighttime environment
    3. It will probably be many years before the majority of people will accept life without dusk-to-dawn outdoor lighting
    4. A dark sky community must be located far enough away from neighboring communities and other significant light sources that the night sky and nighttime environment will not be adversely affected, either now or in the foreseeable future
    5. It is better to live in community than in isolation
  2. Community Attributes
    1. A dark sky community should be multi-generational, but since rural employment options are limited, moving to a dark sky community may be easier for retired or semi-retired folks
    2. A dark sky community should be affordable, with a variety of housing options (units that can be rented, for example)
    3. An observatory commons area should be developed for observing and include more than one observatory for use by members of the community
    4. The dark sky community should engage in an ambitious educational outreach program, including the operation of an astronomy resort and astro-tourism business
    5. The business end of the community should be a nonprofit corporation or cooperative that operates the astronomy resort and rental properties
    6. The community should share resources as much as possible, freeing residents from the financial burden of having to individually own everything they need or use
    7. The dark sky community should engage in an ambitious program of collaborative astronomical research and data collection, working collaboratively within the community and with amateur and professional astronomers outside the community
  3. Community Location
    1. The most affordable option would be to “convert” an existing rural subdivision or small town into a dark sky community, current residents willing, of course!
    2. The best location for a dark sky community would be within, or adjacent to, a protected natural area such as a state or national park
    3. Recognizing that there would be distinct advantages in siting a dark sky community reasonably close to a town or city with medical facilities, it would be best (for astronomical reasons) for the dark sky community to be located southeast or southwest of the larger community
  4. Philosophy
    1. In an age of technological wonders such as digital imaging, computer-controlled telescopes, remote observing, and space astronomy, we recognize that there is still value in the experience of “firsthand astronomy” both for ourselves and our guests

For greater detail, see my astronomy village proposal for Mirador Astronomy Village.  I welcome your comments and ideas here.

Identifying Distant Light Pollution Sources

Ten years ago, I lived within easy walking distance of the south edge of Dodgeville, and on one starry evening, I walked to a favorite hilltop with a good view of the sky just south of town.  To my surprise and displeasure, I noticed a bright light dome in the southeast I had never noticed before.  Where was that light coming from?

Fortuitously, the bright star Antares was at that moment very close to the horizon, and right above the offending light dome!  I noted the time: 10:25 p.m. CDT on 15 May 2007.  And the observing location: 42° 57′ 06.4″ N, 90° 08′ 16.9″ W.

After getting home, I started up the Voyager planetarium software on my Macintosh, set the date and time to the observation time, and the observing location listed above.  I found that at that moment, Antares was at an azimuth of 134.2°.

Now, grabbing a protractor and a Wisconsin state map, I quickly determined that the most likely city along the 134.2° azimuth line from Dodgeville was Monroe, Wisconsin.  Though quite some distance away, could this have been the source of the light dome I saw?

Using a great circle calculation program on the internet and the known geographic coordinates (latitude, longitude) for the two locations using Wikipedia, I determined that Monroe is at bearing (azimuth) 133.5 from my observing location near Dodgeville at a distance of 35 miles.  This matched my star-determined azimuth quite well.

Was there an outdoor athletic event going on in Monroe at that time to cause so much light pollution?

Could the light dome possibly have been coming from Rockford, Illinois?  Even though Rockford’s bearing of 131.1° makes it a suspect, its line-of-sight distance of 71 miles makes this extremely unlikely.

An Open Letter to an Unknown Neighbor

We haven’t met yet.  I’m a non-confrontational kind of person (a typical Midwestern trait, I’ve heard), always eager to please and not to offend.  But I want you to know how much your dusk-to-dawn floodlight bothers me.  You see, I’m an astronomer.  I even have a backyard observatory and I would love to show you the wonders of the night sky if you’re interested in seeing what’s up there.  I’m probably the only person in Dodgeville or Iowa County doing astronomical research several nights a week, weather permitting.  I accurately time when asteroids and trans-Neptunian objects pass in front of stars, blocking their light for fractions of a second up to several seconds.  There is a lot we can learn from such events.

When I moved into my house, I had to install thick curtains in my bedroom because your bright light floods into the room all night long every night.  In fact, your light floods into every window on the west side of my house.

I like it dark at night.  It helps me to sleep better and, I’ve heard, sleeping darker is sleeping healthier.  There’s even medical research that supports this.

Being an astronomer, I like to step outside and check the night sky from time to time, look at constellations—see if the northern lights are active.  All of this is a struggle for me now.  But it doesn’t need to be.

I think I know why you want to have this light.  It seems you are trying to light the stairway from your backyard to your front yard for safety reasons when using those stairs at night.  Have you considered putting those floodlights on motion sensors instead of a dusk-to-dawn timer?  You’d save money on bulbs and electricity.  Or, if you really feel you need the light to be on all night long, a better lighting system could be installed that would light your stairs without lighting up your neighbors’ houses and yards.  Can’t afford it?  I’m not wealthy either, but I’d be more than willing to pay for the lighting improvements, because I want to be a good neighbor and having a dark backyard and house at night means that much to me.  Besides, one of the benefits of living in a small town in this beautiful area of rural southwest Wisconsin is getting a decent view of the night sky.  No big city can compete with that.

I’ll even pay for us to hire a professional lighting engineer to do the job right so both you and I (and probably your other neighbors) will be thrilled with the results.  I know enough about lighting to say confidently we will have a win-win situation.  Guaranteed.

I’m looking forward to meeting you and discussing this.  Thank you.

Outdoor Lighting Codes and Ordinances in Wisconsin

Last Updated: 5/22/2017

Here are all the outdoor lighting codes and ordinances in Wisconsin that I am aware of.  A big thank you to Scott Lind, PE, of Hollandale, Wisconsin for initially putting together this list in 2007!

Please post a comment or contact me via email if you have additions or updates to this list.

Blue Moundsmap
http://www.ecode360.com/27010348

Brookfieldmap
http://www.codepublishing.com/WI/Brookfield/html/Brookfield17/Brookfield17120.html#17.120.070

Chenequamap
http://chenequa.org/wp-content/themes/Chenequa/Documents/Ordinances/Chap5.pdf

Cloverlandmap
http://www.townofcloverland.org/Documents/Ordinances/Code%203.01%20Lighting.pdf

Delafieldmap
https://www.municode.com/library/wi/delafield/codes/code_of_ordinances?nodeId=CH17ZOCORERE411_GEPR_17.235OULIAM491

Delavanmap
http://ci.delavan.wi.us/download/departments/building-zoning/zoning-codes/zc_23-7perstand_code.pdf
See Section 23.707 Exterior Lighting Standards

Egg Harbormap
http://www.villageofeggharbor.org/vertical/sites/%7B569578EA-93E6-481F-B733-DF3296C08FEE%7D/uploads/%7B7B55219C-9B97-4628-AEF1-445C51A0BB09%7D.PDF

Fontana-on-Geneva Lakemap
https://www.municode.com/library/wi/fontana-on-geneva_lake/codes/code_of_ordinances?nodeId=PTIIMUCO_CH18ZO_ARTXDEST_S18-165EXLIST

Fox Crossingmap
http://www.town-menasha.com/departments/clerks-office/ordinances/
Click on section Chapter 29 Development Ordinance and search for “lighting”

Fox Pointmap
http://www.ecode360.com/14717677

Genevamap
http://www.townofgenevawi.com/uploads/documents/ORDIN-59%20Regulate%20Outdoor%20Lighting%20&%20Advertising%20Signs.pdf

Green Lake Countymap
http://ecode360.com/9770791

Hollandmap
https://drive.google.com/file/d/0B1qD1hgbbNz-bWRSWmlkN2o0eEU/view

Kenoshamap
https://www.kenosha.org/images/GENORD.pdf
See Section 4.07 Artificial Light and Glare

Koshkonongmap
http://koshkonongwi.com/download/outdoor-lighting-ordinance/

Madisonmap
http://www.cityofmadison.com/attorney/ordinances/documents/chapter%2010%20-%20streets,%20alleys,%20sidewalks,%20and%20gutters.pdf
See Section 10.085 Outdoor Lighting

Mequonmap
https://www.municode.com/library/wi/mequon/codes/code_of_ordinances?nodeId=PTIICOOR_CH58PLDERE_ARTVSISTDECR_DIV2COINPAINMUMIREDE_S58-567OULIIN

Middletonmap
http://www.ci.middleton.wi.us/DocumentCenter/View/43

Mineral Pointmap
http://skythisweek.info/mineralpointlighting.pdf
Is this lighting ordinance still in effect?  I cannot find it on the Mineral Point website.

Mukwonagomap
https://www.municode.com/library/wi/mukwonago/codes/code_of_ordinances?nodeId=PTIICOOR_CH100ZO_ARTIXSIPLRE_S100-601SIPLARRESTALNOMIPR
See Section e Lighting Standards

New Glarusmap
http://www.newglarusvillage.com/__media/pdfs/ordinances/LightingLandscape.pdf
See Article XVIII Exterior Lighting Plans and Standards

Oconomowoc Lakemap
http://www.oconlake.com/Documents/ord178.html

Richfieldmap
http://ecode360.com/16178580

Shorewood Hillsmap
http://www.shorewood-hills.org/vertical/sites/%7B00D5AF3F-ADFE-4173-AF3A-FC0C1A78DA4B%7D/uploads/Ch_22_Dark_Sky.pdf

Springdalemap
http://www.townofspringdale.org/site_files/editor_files/image/file/Ordinance/031714_pdf_Final_Dark_Sky_Lighting_Ordinance.pdf

Springfieldmap
http://www.town.springfield.wi.us/ordinances/chapter-9/
See sections 9.02(7) Exterior Lighting, and 9.04(7) Exterior Lighting Plan

Sturgeon Baymap
https://www.municode.com/library/wi/sturgeon_bay/codes/code_of_ordinances?nodeId=CO_CH20ZOCO_20.12USREDI
See Section 20.12.(1)(b)12

Sussexmap
http://www.villagesussex.org/vertical/sites/%7B1FD3B636-3BF9-4496-900E-EAA7FFADF5E8%7D/uploads/17.0600_Traffic_Loading_Parking_Access_Storage_and_Lighting-01-2016.pdf
See Section 17.0608 Lighting

Westportmap
http://www.townofwestport.org/Ordinances/Title%209/Title%209%20Chapter%207.pdf

Whitefish Baymap
http://www.ecode360.com/documents/WH3817/WH3817-016.pdf
See Section 16.31 III A2

Williams Baymap
http://www.williamsbay.org/images/doc/Chapter%2015.pdf
See Section 15.03 Outdoor Lighting and Advertising Signs

Winneconnemap
http://ecode360.com/14487227?highlight=260#14487227

The Wisconsin State Law Library maintains a comprehensive list of Wisconsin Ordinances and Codes.  This will be a good resource for us to find additional outdoor lighting codes and ordinances to be added to this list, as well as to check your local government’s codes and ordinances in general.

It is interesting to note that nearly two-thirds of these ordinances are for suburban communities in very light-polluted metro areas.  Another four ordinances are no doubt in place to help protect the Yerkes Observatory (Williams Bay, Geneva, Fontana-on-Geneva Lake, and Delavan).  Where are the rural ordinances and dark sky preserves?  Since there are very few remaining locations in Wisconsin where the night sky is truly dark, shouldn’t we be aggressively protecting those areas?  Wouldn’t it be easier to save a pristine area than to restore an almost hopelessly polluted one? Another interesting point is that upscale suburban communities are much more likely to have a lighting ordinance than more affordable communities.  Some subdivisions even exclude streetlights, but these are almost never places where most of us can afford to live.