Exposing PseudoAstronomy

April 2, 2014

Podcast Episode 105: A Fission Origin for the Moon, Part 1


Could the Moon have formed
By budding off a young Earth?
Or, does that not work?

I know Graham’s not going to be happy, but I’m putting off the Pioneer Anomaly episode for at least another two. Instead, this is the first of a two-parter on the fission model of solar system object formation. You might be thinking that this is a repeat of Episode 53 (lunar formation, though I’m sure you know all the episode subjects by heart), but it’s not. I go much more in-depth into the historic context, evidence for it at the time, but subsequent problems and why no scientist accepts it today (though some pseudoscientists do, which is what I’ll be talking more about in Part 2).

Due to time constraints (lots of cleaning, a “for realz” job interview with USGS tomorrow, and various other things), there is only the main segment and a New News related to Episode 85 (blood moons) — if it’s visible from your location, don’t miss the total lunar eclipse in two weeks!!

Oh, and the Reality Remix interview should be posted on their website, and I’ll be posting it shortly. I suggest clicking on the link for non-Flash users, it might work significantly better.

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October 12, 2013

Podcast Episode 89: Remaining Issues with Lunar Formation, Interview with Robin Canup


What are the problems
With current models of the
Earth’s Moon’s formation?

Another slightly late one, this is the long-anticipated “what’s left in lunar formation?” episode, a follow-on to Episode 53: Lunar Formation and Origins, put up almost exactly one year ago. The episode is an interview with a leading researcher in the field, Dr. Robin Canup, and it’s about a half hour long.

The next episode is still slated to be about the claim that alleged UFO-contactee Billy Meier knew about Jupiter’s rings before scientists did. I expect the comments on that post might fill up, but I’ll note now that no comments to THIS blog post will be allowed on IF they are about Billy Meier material UNLESS they are a suggestion for a puzzler. Generic Meier conversations will be allowed on the next post about Episode 90.

Also, I’m starting to roughly plan out Episode 100. If you have Skype and are good at making stuff up for a few minutes that’s related to anything discussed so far on the podcast, please let me know and you might get on the first three-digit episode.

October 16, 2012

Podcast #53: Lunar Formation and Origins


This was a listener-requested episode, how the moon formed. There isn’t too much pseudoscience in this one, though a few references are made to misconceptions in Mike Bara’s new book. And some misunderstandings by Bob Novella from episode 350 of The Skeptics’ Guide to the Universe podcast.

Since I was trying to get this episode out quickly, several of the normal segments are not present, but I did have a bit of another run-in with David Nabhan, the very “passionate” guy from episode 50 on lunatic earthquakes. If you have maybe 10-15 minutes to kill, I highly recommend reading the exchange starting part-way down that thread on October 4.

January 28, 2012

Talks at Science Conferences Doesn’t Mean They’re Science


Introduction

My work load is starting to diminish from the 80 hrs/week as I prepare to head off to, um, “lovely” Houston next week for a conference on Early Solar System Bombardment (as in big chunks of rocks hitting other, bigger chunks of rocks).

The small conference – such that it’s called a “workshop” officially – has all the abstracts posted online, and I was browsing and downloading them today. I then came across abstract #4008, entitled, “Questions About Lunar Origin.” It’s by Fred S. Singer, and he’ll be talking about it on Wednesday evening during the poster session.

Innocuous Title

The title itself is fairly innocuous, and scientists know that there are questions about how the moon formed the way it did. Of course, if this were like “Intelligent Design” and their “teach the controversy,” then Singer would likely advocate teaching students that there is just as much evidence that the moon was (1) captured, (2) formed in Earth orbit originally, (3) was flung off Earth, (4) was formed when a Mars-sized object hit Earth, or (5) was put here by space aliens.

But I get ahead of myself.

Reading the Abstract

First off, the abstract is not in standard format. Almost all the rest of us put our abstracts in the same, required format by the conference, but there are always some people who think they’re special and don’t have to do what the rest of us do. But I’m not bitter or anything.

The abstract, I think, can be classified as a rant. The first three paragraphs read like a “Woe to the people who accept the impact hypothesis of lunar formation, but if you do …”

The remainder is a list of “12” questions that actually have many questions within them where he basically shows that he does not know how science operates. They read like “… well how do you explain THIS?! Huh!?”

I’m not going to bore you with reiterating everything from his two-page abstract, but I want to point out a few examples just to give you an idea of how pseudoscience works. This is really one of the first very clear-cut examples I’ve seen where someone is arguing about astronomy who is not a creationist in a very creationist way – by pointing out examples of apparent contradiction or lack of consensus in the literature as a way to argue that it’s all wrong, no one knows what they’re talking about, therefore he’s correct.

Example 1

3. At what stage of terrestrial accretion does the hypothetical impact occur? Early or late? Different papers give different answers.

4. What is the mass of the impactor? Twice lunar or more like that of Mars? Different papers give different answers.

These “two” questions are clear examples of, first, not citing your sources (he refers to “different papers give different answers” but he does not give those different answers nor does he list those different papers). Second, it’s pointing out what could sound like major issues to someone who does not know about the subject, but to those that do, it just seems silly.

For #3, the answer is “we don’t know” but we do have constraints. Dating of lunar rocks puts the moon’s formation at no later than 4.527 billion years ago (source). The age I’ve seen for Earth is about 4.54 billion years old (source). Quibbling over whether this was early or late-stage terrestrial accretion (when the planets formed) to me does not seem to actually be an issue in the literature. Hence why it’d be nice to see his “different papers.”

For #4, the canonical mass I’ve always heard is “Mars-sized.” Mars is about 45% the diameter of Earth, while the moon is around 25%. If they were the same density (they’re not), then the mass difference would be the ratio of their diameters cubed (0.45/0.25)^3 ≈ 5.8x different). Mars is actually 10.7% the mass of Earth while the moon is 1.2% Earth’s mass … meaning that Mars is 8.7x the mass of the moon.

Fred is arguing that the factor of 4.4x in range (2x Moon to 1x Mars) is apparently a major issue here. It’s not. There is absolutely no way to know the mass of the original impactor. The range comes about because of different potential impact models (I assume … if I had his “different papers” then I could look). If you have a different velocity or impact angle, you need a different initial mass. If you have a different initial mass for Earth, you’ll need a different mass for the impactor. A difference of a factor of 5x does not seem to me to be a deal killer.

Example 2

6. What happens to the splashed-out material from the impact; how many particles escape and how many return on ballistic orbits? Whence comes the angular momentum for a bound lunar orbit? How and where does “captured” material assemble and what exactly is the initial lunar orbit?

Asking “this” question is missing the point. Dr. Singer has had a varied career in science over the years, but from reading this question I doubt he’s ever done any N-body modeling (the kind of code where you have many particles and you simulate how they interact). If he had, then the question about “how many particles escape” is nonsensical. For example, if you had a simulation with 1 million particles and 10,000 escaped and 50,000 returned on ballistic orbits and the rest did something else, then I just gave you the numbers there. But then if you ran a simulation with 10 million particles you’ll get a completely different answer. Maybe he means “how many” in terms of a fraction?

The “how and where” of the moon’s formation in the impact hypothesis is a head-scratcher. The answer has pretty much always been that it “assembles” in orbit of Earth, actually fairly close to the planet, and the “how” is through normal processes of agglomeration (stuff hits other stuff and sticks).

The exact initial lunar orbit is kinda like a creationist asking, “What was the exact functionality and makeup of the very first cell?” We don’t know, but we can make educated guesses based on modeling and observations of what we see now. He’s asking unanswerable questions in their specificity, but ones that have been answered to most peoples’ general satisfaction.

Final Thoughts

The point of this post is to teach a little astronomy while also pointing out, as the title suggests, that presence at a science conference does not mean what you’re doing is science. Creationists actually have a habit these days of going to geology conferences, presenting something, and then coming back and saying, “See! We presented at a scientific conference even!”

Similarly, this is not to imply that there are no questions about the moon’s origin (as I mentioned above), nor observations that do not fit with the “Big Splash” model that is currently in favor. If you want to bring those points up, that’s fine. But going back and asking questions that are already answered, or cannot possibly be answered to your desired specificity, is not the way to argue your case.

And look, I got through that entire thing without mentioning that Dr. Singer is also a climate change denier.

Update: Singer was the only person to present today who was a no-show. No him, no poster.

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