[HPforGrownups] Full moon question for the folklorists

[Shaun Hately]

No: HPFGUIDX 97492

On 1 May 2004 at 23:19, Silverthorne wrote:

> Silverthorne:
> Oh, I'm not arguing THAT point--What I'm playing at is the fact that the sun
> *is* up at the same time as the full moon sometimes--and that's what I'm
> wondering about. The full moon is UP *before* the sun sets--and yet the were
> wolf legends never seem to take that into account....so it still begs the
> question--does the sun counter act the effects, or is it simply that
> folklore doesn't take that into account since it's basically all about
> 'darkness' and 'evil' (something normally associated with 'evil' things way
> back when the legends first started)? And if Rowling (or *any* author for
> that matter) were to take the fact that the full moon can rise *before*
> sunset (or stay in the sky *after* sunrise), then how would they explain the
> descrepency? It's still a full moon--it's still reflecting visible light
> Earthwards--so the werewolf would still see it, and would, in theory, still
> be 'hit' with it. So why doesn't it make them change then?

I can think of a few possible reasons.

The one I would personally favour is the idea that the moonlight is 
'drowned out' by the 'sunlight'. If the sun is visible, it will 
always be the dominant lightsource in the sky.

Using the lux as a measure of illumination, the light of the full 
moon is roughly equal to 0.27 lux. The illumination of the sun is 
equivalent to anywhere from 32,000 to 100,000 lux - from memory, 
it's around 30,000 lux at sunset or sunrise.

What this means is that *if* the sun is in the sky, it's light will 
always be at least 100,000 times brighter than the light of the 
full moon (and, yes, I know it doesn't seem the difference is that 
much - but that comes down to the way we see light and our brains 
interpret it). Put another way - if the sun and a full moon are 
both in the sky, between 99.997% and 99.999% of all the light from 
natural sources will be coming from the sun.

I don't think it's unreasonable to assume that a light source 
100,000 times brighter drowns out and renders meaningless the 
lesser light source.

However, at night, it's a totally different kettle of fish.

The full moon (at zenith on a clear night) is about 0.27 lux.

A starlit sky (absent the moon) is about 0.001 lux.

So at night, the full moon is 270 times brighter than all other 
natural sources combined.

Or put another way, 99.6% of all light is coming from that full 
moon.

(Just to avoid a possible question, even if the bright planets are 
visible in the sky, they produce very little illumination - Venus 
at its brightest yields about 0.0001 lux - not enough to 
appreciably effect these numbers).

So, if I had to come up with an explanation, I'd start by looking 
at the dominance of different light sources. During daylight, the 
light of the sun simply washes out the light of the moon, to an 
extent it can't have a lycanthropic effect. 

> Which goes back to my original post--what constitutes a 'full' moon for a
> were wolf? If its number of days, then we have an inaccuracy (because Lupin
> is not a were that whole time). If it's activated by 'the phase of the full
> moon', then it's still inaccurate, because the moon is not always
> convieniently full at night, high over head--and it further begs the
> question of what happens to weres on the oppostie side of the planet from
> the 'full' moon? Do they 'beg out' on that month since they aren;t actaully
> expsoed to it? Appearently not.

Just for the record - while technically speaking full moon is an 
instant, most astronomers generally consider it to be about 3 days 
- one night either side of the actual night of totality - when they 
need to use a looser definition. But this is constantly debated.

References I've seen to various withcraft, and astrological 
traditions, tend to focus on either a three day or six day period. 
But I'm a long way from being any type of expert on that.

Personally I think three days is a reasonable 'guess', but an 
author can do what they like. 
 
> And then, again, the ultimate werewolf question--if it's activated by
> *seeing* the full moon--as most legends nowadays tend to ascreibe to (as
> does Rowling with her cinematic treatment of Lupin changing when the moon
> came out from behind a cloud), then the hole there is that they *should*
> change when they see the moon--even if it's up during daylight
> hours....which is why I ask....why is that not thought of?

Probably because if JKR took into account everything we come up 
with, she'd be a stark raving maniac by now (-8



Yours Without Wax, Dreadnought
Shaun Hately | www.alphalink.com.au/~drednort/thelab.html
(ISTJ)       | drednort at alphalink.com.au | ICQ: 6898200 
"You know the very powerful and the very stupid have one
thing in common. They don't alter their views to fit the 
facts. They alter the facts to fit the views. Which can be 
uncomfortable if you happen to be one of the facts that 
need altering." The Doctor - Doctor Who: The Face of Evil
Where am I: Frankston, Victoria, Australia