anti-blue moon?

JRS: In article , dated Wed, 17 Nov 2004
02:14:50, seen in news:sci.astro.amateur, Brian Tung
posted :
As many of you know, the interpretation of a blue moon as the second
Full Moon in a month arose as a misinterpretation of a passage from an
...
If any Sky and Telescope editors are reading this, I'd love to write
an article on this. Wink, wink.

How about, if not already done, writing on the lowest latitude from
which the Moon (Full Moon?) can be seen in the North?

One answer is 90 deg S, of course; the Moon can be seen in the North
(where else?) from there, and can be seen in the North from any less
southerly latitude up to about that of the Columbiad.

But I'm thinking of sightings from further North than there.

The Moon is up for [over] half of the time to an observer at the North
Pole, and is inevitably in the South from there. Let the observer take
a pace backwards, though, and the Moon is then in the North for him.
How far back must he go before the Moon, still in the North, is
completely invisible?

ISTM that he goes to the Arctic Circle, adjusted by +-5 degrees or so
for the tilt of the Moon's orbit (and that is AIUI an adjustment
culminating in early 2006), increased by the usual refraction (hope for
cold dry weather, to maximise that), increased by half of the Moon's
angular radius, diminished more as the Moon is not at infinity,
increased by the effects of whatever local topography is available, and
adjusted in any other necessary manner.

In particular, can this be seen from any part of the UK, such as Muckle
Flugga?

--
© John Stockton, Surrey, UK. Turnpike v4.00 MIME. ©
Web URL:http://www.merlyn.demon.co.uk/ - FAQqish topics, acronyms & links;
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Well, here in New Hampshire (latitude 43 or so North), the Moon is
always south of the east/west Meridian.

Were we talking about the Sun, the answer to your question would
be the anywhere south of 1/4 degree north of the Tropic of Cancer (23
degrees N latitude). At the Tropic of Cancer the Ecliptic (the path
the Sun takes) is at zenith on the summer solstice. The Sun is about
1/2 degree of arc in diameter, so go half that distance further north
and you're at the limit where any of the Sun will be north of the
east/west meridian that passes through zenith.

The Moon doesn't travel exactly along the Ecliptic, so the furthest
north place where you can see the Moon to the north of the
east/west meridian will be a bit north of the Tropic of Cancer.

-Paul W.

On Tue, 23 Nov 2004 22:41:17 +0000, Dr John Stockton
wrote:


How about, if not already done, writing on the lowest latitude from
which the Moon (Full Moon?) can be seen in the North?

One answer is 90 deg S, of course; the Moon can be seen in the North
(where else?) from there, and can be seen in the North from any less
southerly latitude up to about that of the Columbiad.

But I'm thinking of sightings from further North than there.

The Moon is up for [over] half of the time to an observer at the North
Pole, and is inevitably in the South from there. Let the observer take
a pace backwards, though, and the Moon is then in the North for him.
How far back must he go before the Moon, still in the North, is
completely invisible?

ISTM that he goes to the Arctic Circle, adjusted by +-5 degrees or so
for the tilt of the Moon's orbit (and that is AIUI an adjustment
culminating in early 2006), increased by the usual refraction (hope for
cold dry weather, to maximise that), increased by half of the Moon's
angular radius, diminished more as the Moon is not at infinity,
increased by the effects of whatever local topography is available, and
adjusted in any other necessary manner.

In particular, can this be seen from any part of the UK, such as Muckle
Flugga?

On Tue, 23 Nov 2004 22:41:17 +0000, Dr John Stockton
wrote:

How about, if not already done, writing on the lowest latitude from
which the Moon (Full Moon?) can be seen in the North?

If I'm not mistaken, on December 25th, 2004 at about 23:33 local time
the full moon will be visible from almost 50° North (49° 46' N, or
thereabouts).

Wayne Hoffman
33° 49" 17' N 117° 56" 41' W
"Don't Look Down"

http://users.adelphia.net/~w6wlr/

On Tue, 23 Nov 2004 21:01:48 -0800, I wrote:

If I'm not mistaken, on December 25th, 2004 at about 23:33 local time
the full moon will be visible from almost 50° North (49° 46' N, or
thereabouts).

But then, after a closer read of the OP, I realize my comment doesn't
address the question. Oh well...

Wayne Hoffman
33° 49" 17' N 117° 56" 41' W
"Don't Look Down"

http://users.adelphia.net/~w6wlr/