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Old December 8th 18, 08:35 AM posted to sci.astro.amateur
Paul Schlyter[_3_]
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Default Lat/Long and timekeeping system for Mars

On Fri, 07 Dec 2018 11:15:41 -0500, Davoud wrote:
Davoud:
*Figuratively speaking. Due to macular degeneration I do not

look
through telescopes any more.


Paul Schlyter:
Don't you look at the sky with your naked eyes either anymore?


I do, of course. But if you understood what MD does to vision,


I looked it up on Wikipedia, but it's found under AMD = age-related
macular degeneration. Ah, those abbreviations...

especially in low-contrast lighting (and I sincerely hope that you
never understand that!) you would know why I don't spend a lot of

time
gazing with my naked eye or through a telescope.


Last evening I looked at Orion's sword with my naked eyes. Invisible
with direct vision, a blur with averted vision. Polaris is

invisible to
my eyes in conditions when others can easily see it. I can't see it
except under the very best seeing conditions, usually in the wee

hours
of the morning.


I'm sorry to hear about your eyesight problems. It seems like you
still have central vision under bright circumstances though, such as
daylight, or inside under a sufficiently bright lamp.

But the seeing must be really really bad if it visibly affects your
naked-eye views.


You can use the sky itself as a sidereal clock by finding out on
which RA your local meridian is.


Been there, done that, from the mid-60's through the 80's. That

sort of
exercise is a valid hobby, but it's not my hobby. I like to pretend
that I'm playing with the big boys. I know that they don't walk

outside
at the Keck observatory and determine the RA of the meridian

visually
and then go back in and aim their telescopes accordingly. They do

what
I do: click on an object on a computer representation of the sky and
then click the "GOTO" icon. That has the advantage of being a big

time
saver in my environment in which poor weather greatly constrains
observing time.


It's an interesting fact that modern professional astronomers rarely
know the constellations. They don't need to since they just dial in
the coordinates of the object they want to observe with their big
GOTO telescopes. Or they may not even observe themselves,
professional observers observe for them. That's rational for
optimizing the use of available observing time of course, but it
certainly make you lose contact with the skies. It's like if a
professional geographer didn't know where Switzerland or China or USA
were situated without looking them up on a map, and if he wanted to
go there, he just dialed in the geographical coordinates on the GPS
of his self-driving car or self-flying plane and then let it take him
there.