(meteorobs) Insult to injury for the Geminids

[Bruce McCurdy]

> I caught something on the weather channel I had not realized. Not only 
> does the full moon occur practically at the Geminid peak (1647 UT Dec 12), 
> but is also at the closest perigee of the next year (2138 UT Dec 12, 
> Dec+27).

    Wayne: Not just of the next year, it's actually the closest perigee 
between 1993 and 2016. It's a "perfect storm" of Full Moon occurring near 
both lunar perigee and Earth's perihelion. This has the effect of maximizing 
the Sun's influence in the gravitational equation.

> So the moon is the largest and the brightest. It is also at the highest 
> Declination of the next year, at the time when the ecliptic is at it's 
> highest elevation for the Northern Hemisphere.

    Again, not just of the next year, it's the highest declination full Moon 
until the early 2020s. That cycle peaked in 2006 and will again in 2025. So 
it will be very large, very bright, and very high in the sky, rising very 
early and setting very late. At "high moon" it will be about as prominent 
and dominant as possible for northern hemisphere observers. Further 
exacerbating the problem for this observer and no doubt others, is the 
arrival of this winter's snow cover, still bright and fresh. All we need is 
a little high haze and maybe a nice aurora!

    The only good news is that the Moon near perigee is absolutely speeding 
eastward (and slightly south as well), which has a retarding effect on 
moonrise times in subsequent days. Thus the tiny window for early evening 
earth-grazers on Sunday that Joe Rao mentioned. At my latitude the window 
between the end of astronomical twilight and moonrise is all of 11 minutes! 
Given that the Moon is actually within the borders of Gemini at the time, 
it's surprising there is any window at all.

    Bruce
    *****