Monday, March 26, 2012

Internet lunacy

I received an email the other day from someone who asked about the Moon being lit from the bottom.  This was a problem for him.  Why?

Here's the Moon calendar for April 2012.  Note how the waning and waxing crescent Moons are shown with the horns of the crescent pointing either left or right (e.g. April 18 & 24).

Photo : Bresson Thomas


To the right is a nice picture of a waxing crescent moon in its "proper" orientation.

So, what's the problem?  Well, the letter writer stated that he saw the moon lit from below in May 2010 and thought this odd.

Hey, what the fuck's going on here? The crescent is tilted!

Upon searching for a reason on the Internet, he evidently ran into a lot of "conspiracy" theories regarding this and was wondering what my thoughts were.  I did a Google search myself, to see what the big deal was, and stumbled upon a whole slew of discussion board posts, blog articles, and YouTube videos mentioning how people saw the Moon sideways one night or another and thought it was a sign of the coming apocalypse and Christian rapture, an indication of a polar shift (whatever the fuck that is), or the effects of a some rogue planet coming into our solar system (relating, of course, to the mythical Mayan 2012 doomsday).

Good Lord!  Since I was so horrified by these results, I thought I'd write a blog post rather than only respond to the letter writer.  What horrified me?  Not the fact that the Moon was "tilted", it looks like that all the time as anyone who routinely observes the Moon knows full well.  What horrified me was the huge amount of rampant stupidity on the web about this fact.

Here's an example...  Check out this YouTube video from a show on Biblical prophecy.  Scroll ahead to 08:40 in the clip (unless you're a masochist and want to watch it all).  Oh my God!  The Moon's fucking rotated!  And scientists are covering it up!  It's a sign of the apocalypse!  They even mention a paper by an Italian scientist (Dr. Iorio) who talks about the eccentricity of the Moon.  As the guy on the video (L.A. Marzulli) says "Basically, the thumbnail sketch is this... we're looking at the lunar surface doing things that is [sic] eccentric, that normally we don't see" (10:14-10:24).

So, what exactly did Dr. Iorio write?  The paper can be seen here.  Here's my thumbnail summary.  For the past 38 years, scientists have been bouncing lasers off reflectors left by the Apollo astronauts in order to very accurately measure the distance to the Moon and its rate of recession from the Earth.  He claims that these measurements have indicated that the Moon's orbit has become more eccentric during this time.  What does that mean?  Well, when one object orbits another, it doesn't orbit in a perfectly circular orbit, it instead orbits in an elliptical shape.  A fellow named Johannes Kepler figured this out around 1609 and Isaac Newton showed how this is due to gravity around 1687.

The shape of an elliptical orbit is mathematically described by its eccentricity, a value between 0 (a circle or special case of an ellipse) and 1.0 (a line or infinitely stretched ellipse parabola).  The eccentricity of the Moon's orbit, for example, averages 0.0549.  So the moron on the video doesn't understand what eccentricty even means - it has nothing to do with the lunar surface, it describes the shape of the orbit.  The paper by Dr. Iorio claims that the eccentricty has increased over the past 38 years by a value of 9 ± 3 x 10-12 / year.  Keep in mind the average eccentricty of the Moon is 0.0549 (rounded off) and the amount of change claimed in the paper is 0.000000000009.  Very, very small.  He mentions that a trans-Neptunian object (something orbiting out past Neptune) may cause this perptubation, but then goes on to say:

"On the other hand, the values for the physical and orbital parameters of such a hypothetical body required to obtain the right order of magnitude for de/dt are completely unrealistic. Moreover, they are in neat disagreement with both the most recent theoretical scenarios envisaging the existence of a distant, planetary-sized body and with the model-independent constraints on them dynamically inferred from planetary motions."

In other words, it's not fucking likely.  That means that this YouTube video on supposed lunar changes which claims (starting at 1:00) that "The astronomer [Dr. Iorio] does say that these shifts are being caused by a larger planet in our solar system." is a complete lie.  He claimed exactly the opposite!  That it was a "completely unrealistic" scenario!

I could go on and on.  Do a Google search on "sideways Moon" and you'll see for yourself.

Of course, no one who is inclined to believe that this is all a sign of the end times will believe me, but there is a simple explanation.  The Moon calendar I printed above is an idealization.  The Moon will not look exactly like that in the sky.  The orientation of the Moon depends on the Earth-Moon-Sun geometry AND your position on planet Earth.

To understand Earth-Moon-Sun geometry, go back and read my previous post about the phases of the Moon.  Also keep in mind that the Moon's orbit around the Earth is tilted by about 5° from the ecliptic (the path of the Earth around the Sun).  Add to that the tilt of the Earth's axis (23.5°) that gives us our seasons and the path of the Moon through our sky is slightly different every night of the year.  There are certain times when the Moon is setting almost vertically and will thus be lit from underneath by the setting Sun.  It's still the same side of the Moon as always that's lit, just that the geometry of the Earth, Moon, and Sun are a little different.  Here are some examples using Stellarium (go download and play with it, it's fun!).

The waxing crescent from last January 26 at 6:00 pm in the mid-Hudson Valley
The Moon is almost totally sideways!

The waxing crescent in the mid-Hudson Valley on April 25, 2012 at 9:00 pm
Note how the Moon is still tilted a bit


The waxing crescent in the mid-Hudson Valley on June 23 at 9:30 pm
The Moon is even more upright now

In all three of the above images, the red line is the ecliptic, the path of the Sun and planets through our sky (the Moon, as mentioned previously is tilted with respect to the ecliptic so is sometimes to one side of it and sometimes to the other).

What if we changed our latitude?  What if we observe the moon on June 23 from Florida instead of New York?

Miami, Florida on June 23, 2012 at 9:30 pm
Note how the Moon is a bit more tilted than in New York

Hey, what if we went to higher latitudes instead of lower latitudes?

Somewhere up in Northern Quebec on June 23, 2012 (still light at 9:30 pm!)
Note the Moon is more upright here at a higher latitude

The orientation of the Moon depends on time of year and latitude from where you observe it.  For a crescent Moon, if the ecliptic is near vertical, the Moon will be rotated and lit from below from the Sun below the horizon and if the ecliptic is tilted a lot (like the figure directly above), the Moon is lit from more of an angle and will have more of an upright appearance.

What really pisses me off is not that someone sees something they think is odd.  It's perfectly normal for people these days to have no experience with how things look in the sky given our pervasive light pollution, general apathy about the natural world around us, and electronic nightime diversions.  People don't even know what the Moon looks like anymore.

What pisses me off is the widespread belief that either:

a.  Scientists (or the millions of astronomy enthusiasts out all the time with telescopes) are morons and wouldn't notice the fucking Moon is flipping around in the sky, or

b.  There is a worldwide conspiracy among scientists not to tell people that the fucking Moon is flipping around in the sky.

I'm always amazed at how little some people know about how the world works.  I'm not just talking about the Moon's movements or appearance, but about how there are millions of amateur astronomers who observe the sky all the time and how scientists are mostly professors at colleges and universities who couldn't (and wouldn't) keep a secret about some crazy Moon rotation caused by aliens, Jesus, or mysterious rogue planets.  Scientists are normal people with families and mortgages who drink beer and watch TV like everyone else.  They're not like the evil geniuses you saw on cartoons when you were a kid.

Our civilization is doomed.  Not from Jesus coming back to punish wicked people like me or alien invasions or Mayan prophecies of natural disasters.  I'm sure those reading my blog know why I think civilization is doomed so I don't even have to say it, do I?

9 comments:

  1. I do know why civilization is doomed - alcoholic geologists!!
    I am sharing this on Facebook and with my students. Too funny!

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  2. You're a man ahead of our times .... "The waxing crescent in the mid-Hudson Valley on April 25, 2012 at 9:00 pm Note how the Moon is still tilted a bit" and "Somewhere up in Northern Quebec on June 23, 2012....." Let Steve predict the future!

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    1. Stellarium predicts the future. Newtonian mechanics, dude, it works!

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  3. It's actually a parabola, rather than a line, that has eccentricity equal to one.

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    1. You are correct (been a long time since I studied conic sections). Thanks.

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  4. I agree with the Newtonian prediction, it's the photos that impressed me. Anyway, I enjoy reading your blogs and might have to stop being anonymous if I'm to keep commenting. I've also really enjoyed some of the links to other writers, especially for math....and Fibonacci series, slug cats....still trying to get a grip on the simple stuff, many years after school and university.

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  5. Excellent! A completely factual article with half a dozen 'fuckings' AND a 'de/dt'. A rare triple combo. When I was at school the physics teacher told us over and again. "Science happens all the time. Open your bloody eyes!" That was generally when someone asked a fatuous question that could be answered by looking out the window.

    Now I live in New Zealand and I've just looked out the window. OMG! The Moon is upside down! We're all doomed!

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  6. I live in England and luckily we don't suffer too much with the religious crack-pots that you seem to. Keep the blood pressure down and don't let them get to you. Love the blog; great explanations and pictures which have helped with my 'scientific' understanding.
    Many thanks!

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  7. I live in England and thankfully don't suffer as much as you with religious crack-pots. However I have an uncle in the mid-west, so I feel your pain; keep the blood-pressure down and the blogs flowing. Loved the explanations and the pictures which have helped develop my understanding of the Moon. Many thanks!


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