As some of you know, I’m attending the James Randi Education Foundation’s annual skeptics meeting, “The Amazing Meeting” (TAM) this year for the first time. I’m excited to be here, meeting people I’ve grown to look up to for the past few years, getting thrown a shirt last night by Penn Jillette without even having to flash my moobs, gushing at idols, etc.
That said, in the absolute least bitter/arrogant way possible, and with all due respect, I’ve been amazed at the astronomy (and astronomy-related) mistakes that have made their way into talks at this conference.
Edited to Add (07/20/2012): I put an “Addendum” at the end of the post to explain a bit more about McGaha’s errors.
“Astronomy for Skeptics: Investigating ‘Lights’ in the Sky” Workshop
To be perfectly blunt, James McGaha’s workshop was bad. The workshop as a whole was scattered content-wise, not cohesive, and very little of the workshop focused on the advertised content. Besides this, roughly half of his informational statements were factually wrong.
After calming down after the workshop, I wrote down some of the main errors I remembered. Among them …
McGaha stated that the Maya didn’t have any math, they could only count, and that’s what the Long Count calendar was, just a count. True, that’s what the Long Count was, simply a count of days in multiples of 20 and 18 and 13. But the Maya – while not nearly as sophisticated as modern mathematicians despite what new-agers want to think – had a very complex mathematics system for their time. They could count, yes, but they could do things with those counts, and they could make astronomical predictions spanning hundreds of years with a good understanding of celestial cycles.
Technologically, McGaha claimed that all GPS compasses cannot actually tell direction via GPS, that they have a small magnetometer in them that must be calibrated every time. This may be true for some. Might be true for your cellphone, your tablet, and some GPS stand-alone devices. But I have a nice field GPS. It tells direction in part by simply seeing how I’ve walked the last few steps and thus taking a difference of the latitude and longitude in order to tell what direction I’m going. No calibration required. He also said that if you hold a battery close to it, it will throw the reading off. Um, no.
After he was finished doing demos with a two-inch device to a room of 300 people, he got into some photography stuff. Among many other things, McGaha consistently messed up “pixel scale” and “resolution” as well as focus and depth of field. I’m not going to get too much into the latter because I was busy with something else while he was going over it, but for the former … “pixel scale” is when you say something like how many pixels per unit of measure. Like, each pixel in a photo is 2 inches in real life of the object being imaged. Resolution, on the other hand, is how many pixels are there. A high-resolution photo is saying that it’s something like 26 megapixels versus 1.3. It may be the most out of focus, poorly imaged thing where you can’t separate two broad barn doors, but it’s still high resolution.
Later, McGaha tried to demonstrate the motions of the stars through the sky with some laser pointers. He got it wrong. He also had a graphic in his slide show trying to show how we define the coordinate system on the sky. His diagram was a bit wrong in how the celestial poles are defined (not from your local north/south, but exactly from Earth’s rotational axis projected onto the sky).
Finally, one of the last things that he talked about was how your eye tells color. He stated that your eye cannot figure out the color of a monochromatic light source directly, that it needs a comparison source to tell. That’s wrong. He also said that with a monochromatic light source, if you change the intensity, your eye will perceive a different color. Um, no. Take a 5mW and 25mW green laser pointer and your eye will see the same color, not different ones.
Ben Radford and 2012
This was a talk I went to because I wanted to see how a non-astronomer skeptic approached the topic. His half-hour talk was basically a run-down of previous failed doomsday predictions, the classes of doomsday prophetic ideas, some humorous clips and quotes from proponents of this particular one, and then a very very cursory (like, 5 minutes or so) overview of how this got started and the Mayan calendar.
There honestly (and unfortunately) wasn’t much meat to the talk, but when he did talk about the Maya, he made some mistakes. One was saying that the Long Count does end this year. This is wrong. It ends one of the 5125 parts of its cycle, but it ticks over to the next “one up digit” of it (like going from 9999 to 10,000). Another mistake was that Ben appeared not to know that this “next tick” may not be this year. It’s based on a correlation that may be wrong, and likely is based on the latest research. It could be easily off by any multiple of 52 years.
A third error in Ben’s talk was his statement that the “end date” only comes from one Mayan inscription. This was correct until a few months ago. Recently, archaeologists discovered another inscription from very roughly 1000 years ago that referred to it. Not a major issue, but it negated (or seriously minimized) his point, and for someone who is an investigator putting together a talk for a major skeptics conference, I was somewhat disappointed.
Ben also seemed to not realize that this meme did not start with recent movies and and books. It has a definite starting point in the 70s and a bit earlier with a few specific people (such as José Argüellas or John Major Jenkins or Zecharia Sitchen). He held up recent books, not the ones that started it.
I was okay with Ben not doing astronomy nor a summary of what people thought would happen. I was okay with the direction of his talk because, as I said, I wanted to see how a non-astronomer approached it. But factual errors and a lack of research from someone like Ben Radford was disappointing.
I realize this post may have sounded a bit annoyed and crotchety. But this is a skeptics conference where we’re pointing out where OTHER people are making mistakes. We should not be making our own.
Several people have asked me how McGaha got the motions of the sky wrong. Here’s a short, abridged list:
- He didn’t know which way was north in the room even though he had just been demonstrating compasses for the past ten minutes.
- Second, he was trying to show motions of the stars about the north celestial pole with laser pointers but instead of continuously rotating his hand to show them moving around the pole, he just rotated back and forth, effectively running time forwards and backwards. Having taught intro astro for people who don’t know astronomy, they WILL think that’s the actual motion if that’s how you demo it.
- Third, he said that no matter where you are on Earth, no matter what time of year, the stars will always rise 23.5° relative to straight up from the horizon. This is very wrong. For example, at either pole, stars will never rise nor set, but they will move in a circle at the same elevation in your sky.