Continued from previous message.

wall with closed eyes. Do this after checking your vicinity for the 
usual hazards of big city life. A trick that works for some people is 
to stand upright, look down at your feet, close your eyes, and swoosh 
the eyeballs left and right rapidly. 
    When you, with dark adapted eyes, leave your observing spot you 
may for a few seconds be dazzled by the street lights. Be ready.

Darkness and clarity
 ------------------
    For the conurbation that is New York, with 9-1/2 million residents 
and an other 12 or more million in its satellite towns, the City is 
amazingly friendly for stargazing. It rid itself of aerial dirt and 
soot in the 1970s by curbing smokestack and tailpipe emissions. 
Traditional factories transmorphed into offices, which emit 
essentially no obnoxious material into the air. Electrification of 
regional rail and factories also reduced such contaminants in the air. 
    New York is the living atlas of the darksky for examplifying ways 
to conquer the scourge of luminous graffiti. Street after street 
illustrate the strategies and tactics to remove or reduce excess 
skyward emission of light. True, this largely is accomplished by the 
continual renewal of the City, with the replacement structures built 
to the modern mature standards of illumination. 
    The end result is that on Manhattan the normal clearsky 
transparency is fully fourth magnitude, with frequent dips to 4-1/2. 

Sky illuminations 
 ---------------
    You must be intimately familiar with the artificial illuminations 
in your sky to avoid false Milky Way sightings and to cut down on 
wasted trips to your viewing site. Know the patches of sky brightness 
from nearby properties. Bear in mind that these hotspots can be very 
localized and may change location, size, and intensity from block to 
block. It's the situation at your viewing site that's critical. 
    Be wisely for temporary or occasional illuminations, like a 
ballgame, political rally, street fair. 

Overall chances 
 --------------
    High mist or haze, unnoticed casually, will block the Milky Way on 
an otherwise clear dark night. So will the least excess of grayness, a 
Moon still in sky, lingering twilight. On the whole it is a touch and 
go effort with most shots being duds. Most of your inspections will 
turn up nothing of the Milky Way on the nights when the chances do 
look favorable. 
    When sighted, as gaged by reports collected so far, the Milky Way 
is a threshold feature recognized by its fixed place in the stars. 
Wait a minute for any drift against the stars; you may be seeing a 
thin cloud. High airplane contrails would likely be too narrow and 
they dilate and fade over time. A reflection of the Moon onto a high 
elevation haze layer can fool you. 
    All in all, you can be frustrated and discouraged by not seeing 
the Milky Way despite taking all the precautions noted here. It may be 
that after all your peculiar location is just too hostile for the 
Milky Way, as so far is the case on Manhattan itself. 

Confirmation
 ----------
    First we consider the outer boros, off of Manhattan. As long as 
you are sky wisely, take the care in looking, and are overall a good 
bloke, your report is valid. It would be well to call an other 
astronomer to check your sighting, but for the outer boros this is not 
a necessity. Usually multiple reports from a given night and boro are 
wholly independent of each other. 
    Manhattan, on account of its grand importance in the darksky 
movement, requires a tighter rule. Yet even here it has to be loose. 
As long as within the same night two persons see the Milky Way from 
Manhattan, the report is 'confirmed'. The two sightings may be from 
different parts of Manhattan and at different hours of the night. Such 
a lax test accommodates the general impracticality of having at your 
side an other astronomer when you check for the Milky Way. 
    A single report from Manhattan is noted as 'unconfirmed'. Not that 
there is real doubt about what you saw, but merely that there was no 
second report for that night. The lack of a confirming report can be 
due to several perfectly respectable reasons. These include 
unfavorable conditions at the other person's site or absence of the 
person from observing. 
    It would be wise to team up now with an other astronomer, like 
those here in NYSkies, on Manhattan as a check on your sighting. This 
person may be anywhere else but reasonably able to recognize the Milky 
Way from a favorable location. 

Where sightings come from 
 -----------------------
    In the early years since records were kept regularly in the late 
1980s, sightings came from a zone of New York generally south of the 
glacial moraine. This is the southern boundary of the last Ice Age and 
is manifested by the ridge running roughly southwest to east thru the 
entire City. The ridge extends into New Jersey and onto Long Island. 
Along it are the various nabes with Heights, Hill(s), Slope in their 

 Continued in next message.

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