Continued from previous message.

    As an example, you will not see the summer Milky Way in the 
predawn hours in the fall season; it is too low in the northwest. To 
see it in the new spring season, you have to be under the stars in 
those hours. It then runs high in the east to overhead. 
    The Milky Way is also of a fixed brilliance, so you can gage by 
the surrounding sky what chance you have for seeing it. This feature 
makes the Milky Way a more certain target than an aurora, which may be 
of any brilliance. 

Transparency
 ---------- 
    To see the Milky Way you need absolutely no worse than a cold 4.5 
magnitude transparency in the Milky Way itself. Not for the overhead 
or darkest part of the sky, but where the Milky Way sits. Not rounded 
down to 4.5, but a hard and cold needle-pinning 4.5. This is a minimum 
but insufficient condition before being rewarded with a glimpse of the 
Milky Way. 
    The fainter stars you can see, the better are the chances. Have 
with you a chart of the Milky Way zone with key stars labelled with 
magnitudes. A computer planetarium program can make one up for you. 

Viewing location
 --------------
    Because you'll be watching with unaided eye for only a couple 
minutes, the selection of viewing site is vastly more ample than for 
regular starviewing. It can be a darkened stoop, alcove, corner, 
terrace, park. Any place you can walk into, be aware of your 
surrounds, and inspect the sky in peace and quiet. You may, for 
instance, find a shaded patch in a park along your walk home from work 
or get permission to use your house's rooftop after arriving home. 
    There need be no conveniences at the site being that you are only 
momentarily stopping there. Lack of benches or warmth (autumn can be 
awfully raw!) is no issue. Pull up your jacket collar and lean against 
a wall.

Binoculars
 --------
    They will better align you with the Milky Way, pick out the 
fainter stars, and assess movement of the suspected spot against the 
stars. One clue to a false Milky Way patch is that in binoculars it 
still looks like a cloud and not sprinkled all over with tiny stars. 
However, it is the view of the Milky Way by the eye alone that counts. 

Ground illumination 
 -----------------
    The main criterion is that local lamps be out of your face. At 
street level, even in the nabes of the most star-friendly outdoor 
illuminations, you will be hit by excess light beams. These come from 
residual trashlights on buildings, car headlights, old streetlamps. 
The site must be shaded from this clutter of ground illuminations. 
    Blockage by trees (when still in leaf), walls, fences are the 
easiest to look for at a street location. Elevation above the street 
is best for a terrace or rooftop. It seems that once you're a couple 
floors above the street lighting, the grosser interference from these 
lights is below you. 
    This strategy exploits one of the eerie features of New York. It 
is a 'dark' City in that there is little exterior lighting above the 
first few floors and no extreme lighting of towers. 
    It may be feasible to construct a portable light shield to set up 
at your site. Observers have used folded refrigerator boxes, Chinese 
curtains, blankets draped on railings and fences, jackets with 'snout' 
hoods. 
    One fetching possibility is an el platform, practicly unique to 
New York. These sit six or so meters off of the street, above almost 
all street-level lights, and are themselfs modestly lighted. View form 
the ends, away from the canopy. 

Sky exposure
 ----------
    Your site must face the part of the sky where the Milky Way runs! 
Be wisely of compass directions at the site, particularly if the 
street grid is skewed against them. Study a street map. Ideally you 
want the entire zone as much as the instant day and hour allow, so you 
can catch any part of the Milky Way. Recall from above that it shines 
out in isolated spots here and there. You could miss one by an ill-
placed obstruction. 
    Such an ideal place may be found in an open part of a park or 
higher rooftop or even a shaded corner on a hill. In praticality, 
you'll use the location of opportunity, which may well occlude major 
parts of the sky. Just try to get a much of the Milky Way path in your 
sky exposure as possible with preference for the high altitudes, where 
the air is clearer and darker. 

Dark adaption 
 -----------
    It's impossible to get really dark adapted anywhere outdoors in 
New York. You can achieve a good adaption, sufficient for hunting for 
the Milky Way, by closing your eyes for a minute or two while shielded 
from local lights. If feasible, lie in a lawnchair or sit against a 

 Continued in next message.

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