Impressions of a Night Sky Unaffected by Light Pollution
International Dark-Sky Associationhttp://www.darksky.org
Words can scarcely describe what it is like to see a night sky that is unaffected by light pollution. For many, it's a spiritual experience.
Many of us dream of walking out our back door and being engulfed by a night sky so beautiful, so splendid, so overwhelming, that a telescope is not even required to appreciate it. Our ancestors knew such a sky. Without our vigilance, our children and their children will not. It is up to our generation to bring back the night.
In 1995 at Astrofest, Sky & Telescope editor Alan MacRobert described what is perhaps the greatest irony of our time: "Better technology in a poorer environment." Which would you rather have: a night sky unaffected by light pollution and only simple equipment to appreciate it (your two eyes, a pair of binoculars, perhaps a small telescope), or state-of-the art equipment (a large-aperture, computer-controlled telescope, adaptive optics, high-resolution CCD camera and sophisticated image processing software, etc.) in a washed-out, light-polluted sky where the Milky Way is never visible to the unaided eye? Do we accept a future where only a few individuals who have the luxury of devoting a significant amount of time and money to astronomical pursuits will be inspired by the night sky, while the rest of us are deprived of that experience? It is time we paid as much attention to improving the quality of our environment as we do to improving the quality of our equipment.
It is good for all of us who are active in the fight against light pollution to occasionally experience a night sky unaffected by light pollution at least once each year to energize and inspire us to continue our diligent efforts to curtail light pollution. Although it may at times seem like a hopeless task, those who stay the course, become knowledgeable, and abide by the golden rule will find their efforts rewarded by a decrease in light pollution. As anthropologist Margaret Mead once said, "Never doubt that a small group of thoughtful, committed citizens can change the world. Indeed, it is the only thing that ever has."
Here, now, are some general impressions of a night sky that is unaffected by light pollution.
- Stars are visible much closer to the horizon.
- There are so many stars visible that the constellations can be difficult to pick out!
- Many more meteors are visible, on any night.
- The Milky Way is exceptionally bright, with tremendous structure and contrast between the obscured and unobscured regions.
- A wide and diffuse band of the Milky Way towards Scorpius can be seen, whereas normally one sees only the brighter and narrower Sagittarius band in the southern sky (if that).
- There is a huge "black spot" in the sky, just north of Deneb
- Dark nebulae along the Milky Way are easily seen in binoculars and small telescopes.
- The Milky Way can be seen extending from horizon to horizon.
- Faint parts of the Milky Way in Taurus/Auriga/ Gemini are easily visible to the unaided eye.
- The starry sky casts noticeable shadows.
- You can easily see your nearby surroundings by nothing more than the light of the Milky Way.
- Your horizons are utterly black.
- Low clouds appear pitch black against the sky.
- Thin cirrus layers do not significantly diminish the view.
- Unlike light polluted areas, haze does not significantly affect sky quality at night for stars that are not too close to the horizon.
- In a dry climate, or at high altitude, there is no appreciable dimming of the stars (or decrease in the perceived density of stars) from the zenith to the horizon
- The zodiacal light can be easily seen, stretching high up into the sky.
Now, that would be something!Published in the November 1997 issue of the NightTimes