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Re: (meteorobs) Dec 22nd

Hi, list:

I'd like to thank Cindee for posting the article about the big, bright full
moon.  I've been getting calls about it for days.  Personally, I think it's
mostly hype, and there are some things a  group of sky watchers ought to
know before they get too excited.

It's true that the moon will appear bigger and brighter than average on
December 22.  The question is -- will it really be noticeable?

As it turns out, according to my copy of "Voyager for the Mac" software, the
apparent magnitude of the full moon on the 22nd will be -13.1.  The apparent
magnitude of the November full moon was ... -13.1.  I doubt that the
difference of less than a tenth magnitude will be detectable visually.  In
addition, according to the 1999 Astronomical Almanac, the December full moon
will only be about 4 seconds of arc larger than the November full moon,
again a difference that should not be detectable by the human eye.  I
suspect that if you had the November and December full moons in the sky side
by side, you wouldn't be able to tell them apart.

The full moon in May was the smallest and dimmest of 1999 because the moon
was near apogee.  Even so, it was only about 3 or 4 tenths of a magnitude
dimmer than December's full moon, and only about 4 minutes of arc smaller.
Norton's Star Atlas 2000 gives 4 arcminutes as the resolving power of the
normal human eye, so I wonder if even those differences would be noticeable,
particularly in comparison with 7 month old memories of the May full moon.
I know that some people can split the components of Epsilon Lyrae, about 2
arcminutes apart, but I'm still skeptical about the differences between full
moons being noticeable to casual observers.

It's interesting to note that a year ago, the November full moon also had an
apparent magnitude of -13.1, and was actually LARGER in apparent size than
the full moon of December 22.  I don't recall anyone even noticing it,
probably because they didn't have the power of suggestion working on them.

As for this happening only nine days before the official end of the
millennium, that period won't happen for another year.  The next millennium
won't actually start until 2001, and why the media insists on celebrating it
a year early is beyond me.

But that's even farther off topic than the full moon, so I'll shut up now
and go back to waiting for the Quadrantids.

Dave Hostetter
Curator of the Planetarium
Lafayette (LA) Natural History Museum & Planetarium

----- Original Message -----
From: <CindeeMcC@aol.com>
To: <meteorobs@jovian.com>
Sent: Wednesday, December 15, 1999 10:12 PM
Subject: (meteorobs) Dec 22nd


>
> I was curious what shower is to occur on the 22nd, particularly since I
> recieved this from a friend today & thought the group would find it
> assumingly of interest, so I pass it on.
> Cindee
>
> This is a short edited version of an article which appears in this month's
> Discovery Magazine. This has not been released on line as yet.
>
> Millennium Dance: The Sun, Moon, and Earth create a Y2K, Cosmic style
> by Bob Berman.
>
> A better time to celebrate a truly once in a thousand year event arrives
some
> nine days earlier than the official end of the millennium. This year's
> December 22 winter solstice coincides with a full moon, a combination that
> happens only every 3 decades or so...But that's not the only celestial
oddity
> for the day:
>
> The moon also reaches perigee, its closest point to the Earth. So this
> solstice, which brings together the year's lowest sun and longest night,
> comes at the same time as the closest moon - and a full moon to boot. The
> last time the full moon, lunar perigee, and winter solstice fell on the
same
> day was in 1866. But even then, the moon merely reached its closest
approach
> of the month.
>
> On December 22, the moon will be at its nearest point of the year. It's
the
> kind of event that would have drove "primitive" cultures bonkers!! And
> believe it or not, there's more...The day of Earth's maximal tilt (when
the
> axis is directed most fully away from the sun) will also combine with a
very
> CLOSE sun...which reaches its nearest
> point to the earth, 12 days later.
>
> The confluence of all these forces at "the very least" will brew up huge
> proxige an tides, also called "closest of the close moon" tides. They will
> extend a few, but crucial, inches farther then normal, ranging from
reaching
> the boardwalk highs, to lows that uncover rarely exposed marine life. If
you
> add a low pressure storm at sea scenario to this to this day, unusually
> strong tides could go over the edge and even
> earthquakes occur more often during strong tide effects.
>
> The cosmic culprits responsible for all this drama, the moon and sun,
occupy
> opposite ends of the sky on December 21-22. A full moon will rise just as
the
> sun goes down in its leftmost position of the year along the horizon. This
> exceptionally
> plump moon will seem a full 14% wider then than it appeared at apogee, its
> farthest point from the Earth.
>
> Long ago and early on in the experience of using calendars, years end
always
> coincided with the winter solstice. That changed during the switch from
the
> Julian to the more accurate Gregorian calendar, beginning in the sixteenth
> century. What seems to have been lost was a much more appropriate time,
from
> a celestial point of view, to celebrate the passing of 1,000 years, when
on
> December 22, the sun, moon, and Earth perform a truly, genuinely once in a
> millennium dance.
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