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Moon Phases


BobbyO

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BobbyO, 

 

Long time, no posting - I could have sworn that I threw some numbers up here but apparently not.  This is really just to start setting a baseline, as I am sure that the sample size is too small to be meaningful.

 

I used the encounter information that I most recently vetted - New York, Vermont, western Mass, and Western CT.  That is a total of 331 encounter reports.

 

The moon phase (my $0.02) not going to be important during the day, so narrow it down to encounters occuring during dusk, nighttime, and dawn, and two where even the general time of the encounter is unknown - that drops our sample down to 172 encounter reports.

 

Of these, only 93 reports include specific information about the moon phase OR the date OR enough information where one or t'uther can be inferred w/a reasonable degree of certainty.  

 

Now before providing any more numbers, there is another area of potential error/disparity.  The "full moon" only lasts one day.  But many casual observers don't distinguish between the true full moon and the moon seen, let's say, 1 day before or 1 day after the full moon.  Similarly, when does a waxing quarter moon become a waxing gibbous moon?  The date ranges that various researchers select for each category may introduce some slight errors.  In addition, there's a huge problem created if a database does not have the option of leaving the date blank (when the date of an encounter is unknown) but instead uses a default date (e.g. the first of any given month) and then sets the moon phase according to that default date. 

 

Back to the numbers - of the 93 encounter reports in which a moon phase was given or could be identified: 

12     occurred during the new moon + 3 nights after

18     occurred during the waxing quarter moon (two nights before, the QM, and 1 night after)

18     occurred during the waxing gibbous moon (the next 4 nights)

13     occurred during the 2 nights before the full moon, the night of the full moon, and 2 nights after the full moon)

  7     occurred during the waning gibbous moon (the next 4 nights) 

12     occurred during the night of the waning quarter moon and the 3 nights after the waning quarter moon

13     occurred during the last 4 nights of the moon cycle

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Admin

Thanks all for the kind words.  I have trouble remembering all the phases, so here is a handy chart from the SSR:

 

post-338-0-20399800-1424308179.png

 

BobbyO, I do have a question...  I want to run the same stats for our research area in WV.

 

Do you count the First Quarter and Last Quarter moons in your stats? 

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G, 

 

Not really sure if I'm reading your post above as intended, but that chart does illustrate the issue of where to assign encounters.  (I just throw the new moon in w/the waxing crescent, so we're not really talking about any different phases.)  

 

As with bigfoot, I do not claim to be an astronomy expert.  Relying on the expertise of the internet (Yahoo! Answers to be exact), I verified that "technically" the First Quarter, Full, Last Quarter and New moons occur at specific times and then pass immediately.  Since, it takes the moon 29.5 days to cycle through it's phases, each of the 8 phases above (in your post) have to cover just under 4 nights (29.5/8 = 3.6875 nights f/each phase).  All of my phases cover 4 nights, except the full moon, which is 5 and thus I end up with 29 nights/moon phase.

 

I use Star Date Online to verify moon phases, but often when sitting there looking at the moon phase for a specific date, it's fairly hard to tell whether it should be a waxing crescent or a waning gibbous or what not.  That's why I set myself specific criteria for each phase.  That way, when I find the correct date, I get accuracy and consistency in assigning the correct moon phase.  Since the SSR is tied to something (I have no idea what) that does this automatically, it also gets accuracy and consistency.   

 

I'm pretty sure BobbyO does distinguish between first and last quarters.  Originally, I didn't as the amount of light is the same (other factors being equal) regardless of which quarter moon it is.  But he convinced me otherwise (during this thread) and so I went back and reworked my moon numbers. 

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That would be the Guy above this post ( Gigantor ) who flies under the radar yet without him, what we are doing wouldn't be possible so he really IS the man, and Redbone too who is putting in some serious hours currently that will be absolute priceless where the long term goal is concerned.

 

Thank you for the kudos :geek:

 

Here is all of the BFRO data that was complete on January 08th compared to what is done today! You may have to click on the image to see the animation because of the size. On Jan 08 I had completed Missouri, Iowa, Illinois, Minnesota, Wisconsin, and Michigan. Since then I have completed North and South Dakota, Nebraska, Kansas, Indiana, Ohio, Montana, Wyoming, and Colorado. I'm presently plugging away at New Mexico and Nevada, with Utah, Idaho and Arizona to follow.

 

The states I've done (with exception of Michigan and Ohio) probably don't have enough sample size for proper moon phase analysis but maybe we can combine neighboring states where possible.

post-21915-0-03091300-1424312122_thumb.g

Edited by Redbone
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^^^^

"...but maybe we can combine neighboring states where possible."

 

Redbone,

 

Looks like you'd have to search each state individually, write down the totals by moon phase, and then add it up when you get all the states you want.  I don't see a function that allows a multi-state search. 

 

EDIT: Forgot to add that you can search w/in a given number of miles of a certain lat/longitude, which would be similar to a multi-state search. 

Edited by Trogluddite
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Admin

I use Star Date Online to verify moon phases, but often when sitting there looking at the moon phase for a specific date, it's fairly hard to tell whether it should be a waxing crescent or a waning gibbous or what not.  That's why I set myself specific criteria for each phase.  That way, when I find the correct date, I get accuracy and consistency in assigning the correct moon phase.  Since the SSR is tied to something (I have no idea what) that does this automatically, it also gets accuracy and consistency.

I think we are on the same page. The relevant point is how much moonlight there is in a given night, first/last quarter moons produce the same amount of light, my question is do you categorize those to more light or less light?

For the SSR, I used a published NASA formula, it's just math, to calculate the moon phase. It doesn't take into account the inclination of the earth, so it's accurate to +-20 hours or so.

 

I'm pretty sure BobbyO does distinguish between first and last quarters.  Originally, I didn't as the amount of light is the same (other factors being equal) regardless of which quarter moon it is.  But he convinced me otherwise (during this thread) and so I went back and reworked my moon numbers.

hummm... so do you classify sightings that occur during first/last quarter as more light or less light? since those two phases put out 50/50 or so... that's what I'm not sure about.

Edited by gigantor
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^^^

BobbyO and Hiflier made a point earlier in this thread (or maybe elsewhere, I forget which) that it's not just the amount of light (e.g., a quarter moon), but whether the amount of light is increasing or decreasing relative to the amount of light the prior night.  There was also a chart that showed that lion attacks occurred more frequently in the waning phases than in the waxing counterparts.  The theory being that humans forgot, night to night, that there would be less light and thus become easier prey.  

 

I realized that I didn't know enough about the topic.  Originally, I just used three categories - 1) gibbous/full moon (you can go out and read by it, which I've done), 2) quarters moons, and 3) new/dying moon (so dark you can't see your hand in front of your face).  I tweaked it into my current categories after reading the earlier comments in this thread and the darn lion attack chart, which really seemed to indicate that either the prey or the predator acted differently in the waxing moon phases.  

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That makes sense, kinda like assigning a weight to each phase based on which direction it's heading. Wonder what kind of metric we can get out of that...

 

I have to go back and read the whole thread...

Edited by gigantor
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SSR Team

 

Now before providing any more numbers, there is another area of potential error/disparity.  The "full moon" only lasts one day.  But many casual observers don't distinguish between the true full moon and the moon seen, let's say, 1 day before or 1 day after the full moon.  Similarly, when does a waxing quarter moon become a waxing gibbous moon?  The date ranges that various researchers select for each category may introduce some slight errors.  In addition, there's a huge problem created if a database does not have the option of leaving the date blank (when the date of an encounter is unknown) but instead uses a default date (e.g. the first of any given month) and then sets the moon phase according to that default date. 

 

Absolutely and I completely agree, but......

Like so much within analysis of many thing, we have to draw a line somewhere in order to be able to calculate.

There must be a day when a waning crescent turns in to a last quarter moon and that day that is decided would be the day that we calculate from, otherwise we'd just have one continuous moon cycle.

Yes that can/could increase the potential for error/disparity like you say but overall, we would be talkng about a tiny % if any of reports that fall on those days.

It's the same with all analysis, as long as you are transparent and you clarify the details of the data set you are studying and what it is for all to understand, then you're fine as of course it would be understood that you can alter the specific focus areas of analysis which would then alter the results anyway.

Clarity is key.

Thanks all for the kind words.  I have trouble remembering all the phases, so here is a handy chart from the SSR:

 

attachicon.gifmoon-phases.png

 

BobbyO, I do have a question...  I want to run the same stats for our research area in WV.

 

Do you count the First Quarter and Last Quarter moons in your stats?

I do.

I include the first quarter as a phase that is one of the lightest phases as is it one of the four phases that would emit the brightest light, and I include that last quarter as one of the darkest moon phases as it, as it wanes, is one of the phases that emits the least light.

But you don't have to, this is what I'm getting up with the above post.

To save that potential for error/disparity, you could choose to leave out those specific phases, or any specific phases if you wanted to.

You just have to make sure that you clarify and are transparent with that when you release the data results.

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SSR Team

I'm pretty sure BobbyO does distinguish between first and last quarters. Originally, I didn't as the amount of light is the same (other factors being equal) regardless of which quarter moon it is. But he convinced me otherwise (during this thread) and so I went back and reworked my moon numbers.

Here we go G, bingo.

Trog would leave those phases out initially in his analysis as he wanted to reduce that potential for error/disparity that he talked about.

My belief however when including them is that ultimately, these moon phases are important as they increase/decrease light emission/omission and like I said before, like with all analysis we have to draw a line somewhere in order to calculate.

Here's a chart that shows the % of light which I hope would make things clearer as to why I add these phases.

http://www.calendar-365.co.uk/moon/moon-calendar.html

You can see that from the last quarter ( I include as one of the darkest moon phases as the day after we have 41% brightness ), light would decrease day by day and from the first quarter ( I include as one of the brightest moon phases as the day after we have 53% brightness ) light would increase day by day.

Edited by BobbyO
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This is really good stuff. The more I read the more I learn. Once again thanks to all for putting in the work to get us to where we can work with it. 

BobbyO I agree with your response to my question. When we look at the general profile most of us assign to BF intelligence is certainly high on the list of attributes he carries. If we are right and they do take advantage of this it simply adds to their "mojo"

Knowing when a few nights of maximum darkness are approaching is an advantage to be pressed whenever possible...whether it is to hunt or to move a family group through a danger zone and avoid detection by us.

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...

I include the first quarter as a phase that is one of the lightest phases as is it one of the four phases that would emit the brightest light, and I include that last quarter as one of the darkest moon phases as it, as it wanes, is one of the phases that emits the least light.

....

Is this accurate?  In either the first or last quarter, approximately the same amount of moon surface is reflecting light back at the earth.  It is getting darker night-to-night, but if you lay the two phases out parralel to each other, starting from 0% surface reflecting (the night before the new moon) and running up to 100% surface reflecting (the full moon), the same phases, whether waxing or waning, have the same amount of surface area reflecting light back toward the earth, don't they?

 

Seriously ... they do right?  (Now I'm wondering if I can still find my 8th grade science teacher around...)

 

So allowing for other factors - clouds, degree of rise over the horizon, etc - the amount of light is the same, its just increasing as the moon waxes (poetic) and decreases as the moon wanes. 

 

Edited to update after reading the next post and chart:

 

Actually, the strange thing in that chart is that it shows the waning phases as having a greater percent illumination than the waxing phases.  (see days 16 and 17, then 19 and 20).  No wonder I flunked out as an astrology major. 

Edited by Trogluddite
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Admin

You are not taking into account the craters and surface features of the moon. The "sea of tranquility" reflects less light than the mountain ranges.

 

Really Trog?  are you serious?

 

:o

Edited by gigantor
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Question for BobbyO and gigantor -

 

Just as the 24 hour cycle is broken into light and dark periods we call day and night, the dark period is usually split into parts when the moon is above the horizon and parts when it is not.

 

Do the illumination values you're using when comparing BF activity take into account whether the moon is above the horizon and visible or not at the the time of the activity or only the moon phase?

 

MIB

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Only the moon phase. Visibility of the moon from the witness perspective would require knowing the exact time of the sighting, the witness's longitude / latitude at the time of the sighting, then calculating the earth's inclination relative to the moon at the time.

 

It's not feasible because we almost never have the exact time, but also because of the other variables.  There is a formula for calculating it, but the sighting reports often don't include enough info to make it worth while.

 

Then, there is the weather, what if it's overcast?

Edited by gigantor
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