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(meteorobs) Starlight in your eyes
I have ran across something in the new AAVSO Manual for Visual
Observing of Variable Stars, Revised Edition January 2001 that should
be of interest to all meteor observers. On page 16;
"... The iris gradually constricts with age; children and young adults
have pupils that can open to 7 or 8 mm in diameter or larger, but by the
age of 50 it is not unusual for the maximum pupil size to shrink to 5
mm, greatly reducing the amount of light gathering capability of the
eye. The cornea and lens together, act as a lens of variable focal
length that focuses light from an object to form a real image on the
back surface of the eye, called the retina. Because the size shrinks
with age, the retina of a 60-old person receives about one third as much
light as does that of someone who's 30."
I will be 80 in May. Even if my loss were only the one third of a sixty
year old that would mean that the best site I found by my measure of 5.5
was actually 6.9 (2.5^.333 + 5.5) or essentially a 7.0 sky. That site
was the parking lot at the top of mount Pinos in the Los Padres
National Forest in Ventura County of Southern California. The
conditions were ideal in that the clouds (fog) covered the San Joaquine
Valley to the North. It is not an ideal site for meteor observing
because of the tall pine trees that surround most of the lot. I might
add that the dew was extremely heavy that night and it quickly froze to
a heavy sheet on my sleeping bag. I left early because I could not keep
my glasses clear. I have only surveyed 5 or 6 sites in Southern
California.
I am hoping to buy a camera suitable for photographing meteors and
in that way perhaps combine variable star observing with meteors. I
recognize the name of at least one other member of the IMO that does
that.
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