Slide 1 New Hampshire's Dark Skies: a Natural Resource in Need Of
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Slide 1 New Hampshire’s Dark Skies: A Natural Resource in Need of Protection • A Few Easy Steps for Preserving Our Dark Skies – At No Cost Slide 2 There’s so much to see if the sky is dark! Slide 3 Visible in NH: Comet Macholz Skims by the Pleiades in January 2005 Slide 4 Making Star-Trails: Mount a digital camera on a tripod, point it at Polaris (the North Star) and leave the shutter open for an hour or two Slide 5 The Pinwheel Galaxy – Visible in small telescopes Slide 6 Saturn: Visible with a small telescope from a billion miles Slide 7 The Sombrero Galaxy: Visible with a small telescope from 27 million light-years away Slide 8 The Beehive Star Cluster in the Winter Sky – A Binocular View Slide 9 The Globular Cluster in Hercules – Visible with binoculars in summer Slide 10 “Eskimo Nebula” as seen by the Hubble Space Telescope Slide 11 Crab Nebula in Taurus: Shattered remains of an exploded star, visible in daytime in July, 1054 A.D. and by telescope now Slide 12 • The Great Nebula in Orion – The Middle Star in His “Sword” Slide 13 The Pleiades – Winter’s Brightest Star Cluster Slide 14 The Double Cluster in Perseus – Easy to see with binoculars all year Slide 15 The Andromeda Galaxy: Most distant object you can see with the unaided eye (2.5 million light years away) – and easy to find in our still-dark skies. Slide 16 Northern Lights on December 14, 2006: Visible only in dark skies – which are as easy to save as they are to lose. Slide 17 Cassini Spacecraft’s view from Saturn: The pale blue dot below is us… Slide 18 With an added glow… A satellite image shows intense urban light pollution along the US East Coast Slide 19 Digital Map of Light Pollution (in blue): Most of New Hampshire’s night sky is still dark. Let’s keep it that way. Slide 20 Only 10% of Americans can still see the stars as our grandparents did. How can we make sure that includes us? Slide 21 The Problem: • 1. Dense population = dense lighting • 2. Unshielded lighting projects light up • 3. Upward light reflects off dust, moisture, causing “sky glow” = Light Pollution • 4. Sky glow washes out faint stars Slide 22 Bad Lighting: Intense and poorly shielded Slide 23 Poorly shielded lighting wastes energy: Why light up the rooftops? Slide 24 Upward sign lighting adds to “sky glow” Slide 25 Solutions: We can’t stop population growth, but we can fix the lighting: • 1. Properly Shielded lighting points all light down, saves energy, avoids irritating glare and “light trespass” • 2. Use minimum necessary illumination for the job Slide 26 This “full cut-off” fixture allows no light above the horizontal – and puts light where it’s needed, on the ground Slide 27 The Ossipee Library shows “Dark Sky” fixtures can be attractive. And they cost no more than polluting lights. Slide 28 Downward sign lighting is thoughtful sign lighting Slide 29 Bad: Wallpack (left) throws light up and sideways, wasting energy Good: Shielded “shoebox” fixture (right) directs light downward, where it’s needed Slide 30 Bad: Typical “Yard-Blaster” (left) throws light up and sideways Good: Opaque reflector (lamp inside) directs light downward Slide 31 Modify Existing Floodlights: Angling light up (left) defeats purpose of shielding. Point it down. Slide 32 Solutions: Simple regulations that require fully shielded outdoor lights 1. The Night Sky is a natural resource that needs protection. Ask your Conservation Commission (CC) to get involved. 2. Urge your CC to propose simple regs to Planning Board and Selectmen 3. Goal: Design standards for Site Plan Review and Subdivisions (no town vote required) and Zoning Ordinance (town vote required) Slide 33 Is it Difficult? • Doesn’t have to be. More than 30 NH towns have adopted “Dark Sky” lighting regs • See the excellent backgrounder: NH State OEP Tech Bulletin 16 from 2001 • For more information, see the International Dark Sky Association at www.darksky.org Slide 34 Basic Night Sky Regs 1. New commercial lighting should be fully shielded (“full cut-off”) to allow zero light above the horizontal 2. Sign lighting should be directed downward 3. Minimum necessary illumination by IESNA standards (Illuminating Engineering Society of North America) 4. Exceptions for flags, seasonal, emergency lighting; existing fixtures grandfathered Slide 35 What about Streetlights? • Often a major source of sky glow • PSNH wants to help • They will install modern, energy-saving lights with full-cutoff fixtures if asked • No up-front cost to towns • Towns pay by energy saved • Talk to PSNH about a Streetlight Conversion Program for your town • NH Cooperative also promotes Dark Skies Slide 36 The Bottom Line • The night sky is a natural and scenic resource of rural New Hampshire • It’s part of what tourists come to see • Preserving the night sky poses no economic burden • Good fixtures cost no more than bad • Simple regulations requiring “Dark- Sky” certified fixtures will do the job • It’s mainly a matter of awareness --Robert Gillette, Ossipee Slide 37 Credits All photos by amateur astronomers except as noted • Comet Swan – Gerald Rheman / www.astrostudio.at • Milky Way, Comet Macholz, Crab Nebula, Saturn, Orion Nebula, – Johannes Schedler / www.panther-observatory.com • Star Trails – Josch Hambsch / www.astronomie.be/hambsch/ • Pinwheel Galaxy – Dr. Steven Mazlin / www.fourthdimensiona stroimaging.com • Sombrero Galaxy – Ken Crawford / www.rdelsol.com • Beehive, Hercules, Pleiades, Double Cluster, Andromeda Galaxy – Dr. Robert Gendler /www.robgendlerastropics.com • Aurora – Stan Richards / www.nightskyevents.org • Lighting Photos from Ossipee – Robert Gillette • Diagrams from the International Dark Sky Association / www.darksky.org • Satellite image of nighttime earth - NASA .