The Humble Pie Report

by Brian Dunning
July 28, 2026

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Once again, I hang my head in shame, and dedicate an episode to corrections of errors made in previous episodes. Most of you seem to have your acts together pretty well, so I rarely get away with getting something wrong — not for very long, anyway. People send in corrections all the time, probably catching about a half dozen a month, and every time one of them checks out, I add it to a list and put out an episode like this one every time I have enough to fill a show. However, probably half the corrections sent in are themselves wrong, which costs me time and effort to double check. But as you can probably imagine, listeners’ favorite corrections to make are corrections to my corrections. So listen to today’s show closely, and if I’m getting the same thing wrong twice in a row. I’ll tell you right now: I’ve eaten my humble pie more than once.

Let’s get started out in the far reaches of the solar system:

Galileo or Cassini?

Episode #1,025 was a pop quiz testing your knowledge of weird things about space, including some wacky conspiracy theories. Among these was the belief that NASA once tried to explode Jupiter and turn it into a sun by crashing a probe into it — a probe powered by a radioisotope thermoelectric generator (RTG), which is filled with plutonium; and which the conspiratorially fluent but scientifically illiterate believe makes it a nuclear bomb ready to explode at any moment. The probe in question, I said, was Cassini. Listener David wrote in:

Hello - I am listening to episode #1025, the Pop Space Quiz. Regarding Question 1 about Jupiter: Either the conspiracists are really confused, or you made a mistake. NASA's Cassini spacecraft was a Saturn orbiter that carried an atmospheric probe from the European Space Agency. There was an earlier similar NASA mission, Galileo, that was a Jupiter orbiter with an atmospheric entry probe. Both were powered by RTGs. Both orbiter spacecraft ended their missions by entering their planet's atmosphere and burning up — and neither Jupiter nor Saturn has turned into a star.

It so happens that David is a lunar and planetary scientist at the John Hopkins Applied Physics Lab and also a premium subscriber, so I deigned to actually read his correction. The funny thing is I actually did a whole episode about that conspiracy theory — “The Lucifer Project” way back in episode #143 — where I got that right. You’d think I could have at least looked at my own article for basic reference. Anyway, I’ve no idea how I managed to name the wrong probe — I meant Galileo, not Cassini. Thanks, David!

Orders of Magnitude

Episode #1,019 was about a device with the completely irrelevant name of Thunderstorm Generator. It does not generate thunderstorms or anything else; it’s a rehash of a very old idea for slightly improving the combustion of old carbureted engines. It’s sold by a guy with an extremely sketchy history of duping investors, so we can guess what his business model is here. Listener Jon wrote in:

In the Thunderstorm Generator episode there is a reference to 124 mm. I think it should be 124 nm. Thanks for your publications and best wishes.

And sure enough, he was right — in the recording, I said “millimeters” when it was supposed to say “nanometers” — I think what happened is my autocorrect changed nm to mm and I didn’t catch it. That can happen when I’m recording; I’m in a whole different mindset from when I’m writing, and can easily make such errors without noticing. This was in reference to wavelengths of light. Light with a wavelength of 124 millimeters wouldn’t be light at all; it would be Wi-Fi. Such is the risk of making an error of six orders of magnitude.

Is It Hard or Easy to Fall into the Sun?

Episode #1,003 was about weird science findings, one of which is the fact that it takes much less energy to fling an object from the Earth to outside the solar system than it does to drop it into the Sun. It seems counterintuitive, because you’d think the Sun has enough gravity to pull anything in that’s coming even roughly in its direction. But no, you have to aim just right — otherwise you’ll miss and the Sun’s gravity will slingshot you into a wild eccentric orbit. In fact, I said the speed needed to slow an object down from the Earth’s orbital speed to a dead stop, so it would fall straight into the Sun, was so critical that you couldn’t miss it by more than 1 km/h.

Well, quite a few of you wrote in with this error. The Earth scoots along on its orbit at a speed averaging around 200,000 km/h, so you can imagine that 1 km/h is an incredibly precise amount. Far more precise than necessary. I had done the math in a back-of-the-envelope kind of way, and so many people caught my laziness that I went back and did it properly. In fact, you need to slow an object down to a dead stop as the Earth goes zipping away on its orbit, but you can miss by up to 5,160 km/h in either direction (too fast or too slow) — the Sun is big enough that your object will fall in and hit it. That’s a range of 10,320 km/h compared to my original 1 km/h. This time I was off by only four orders of magnitude. Yay! I’m getting more and more accurate.

Actually, I’m getting less accurate — since this episode was earlier than the one where I was off by six.

Polyvagal Vaguery

Episode #816 was about Polyvagal Theory, a heavily marketed trend in therapy that combines psychotherapy with some quasi-physiological neurology — and also attracts scads of unlicensed “polyvagal coaches” who sell their own notions of it. It’s kind of complicated, so check out that episode if you want the details.

Anyway it involves the vagus nerve. Listener Joe wrote in:

You state the Vagus Nerve is part of the Sympathetic Nervous system (“Fight or Flight”) but it's actually the Parasympathetic nervous system.

I already knew this (ICU Nurse here) but Chat GPT helped me just summarise. Whilst the episode correctly points to the vagus as the cause of Hiccups, it's not part of the sympathetic nervous system.

And right Joe is. Going back to my notes for that show, I see a tornadic jumble of sympathetic, parasympathetic, vagal and vagus and mobilized and immobilized and everything else. And, not being an autonomic neurologist, they are all Greek to me; so I’m happy to have scored 9 out of 10 on this one.

DNA on the Shroud of Turin!

Episode #795 was about the Shroud of Turin — not about whether it’s genuine, because all existing evidence makes it very clear that it’s a recent forgery created as a fundraiser by six French clergymen — but about why it became an immortal topic of debate. During the episode, I talked briefly about the stains claimed to be blood from Jesus himself, but which have conclusively been proven to be tempera paint. And, I said, tempera paint doesn’t contain DNA.

But then listener Allan came along with this to say:

Hello Brian —

After years of listening to your correction episodes and feeling left out and half-witted that I never catch any gaffes myself, I think I finally have one to contribute. It's been a long time coming, so you know it's going to be earth-shattering:

I was listening to an old episode, #795, about the Shroud of Turin. At about 5:49 In that episode you state, “...and the bloodstains have been chemically identified as tempera paint, and so don't contain any DNA...”.

But of course tempera paints do indeed contain DNA. Just not human DNA. An important component of classically made tempera paint is egg yolk, and while there is actually more DNA material in the egg white (yes, I had to look that up), egg yolks do absolutely contain chicken DNA.

I know, I know. How did this planet continue to revolve with such an enormous error unresolved.

Well, I have no excuse for this one. It never even occurred to me that tempera paint might have chicken DNA in it; I just assumed it came from minerals or wax or oil or whatever old paints came from — a set of candidate compounds which probably should have included organic matter but did not.

Upon receiving Allan’s note, I looked it up, and sure enough, old tempera was made using egg yolks as the binder for matte finishes — and while modern tempera uses starch or polyvinyl alcohol instead, traditional temperas are still available for the purists, chicken DNA and all. So — color me corrected. Thanks Allan, and congratulations on finally getting one in!

Not Your Grandfather’s Griffins

Episode #442 was about griffins, mythological creatures from Middle Eastern and European cultures — basically the head and wings of an eagle on a lion’s body. This episode was guest written and hosted by paleontologist Ryan Haupt, and at the time (2014), the common wisdom was that the legend of the griffins arose from misidentified Protoceratops bones.

But a year or so ago, Ryan emailed me that things had changed in the intervening decade, and he sent me a 2024 article from Popular Science that summed things up. Two paleontologists from the University of Portsmouth had focused serious attention on this claimed explanation, and found that each of its bits fell apart under scrutiny. So today, we no longer have a tidy explanation for the griffin mythology — but neither do we have a newer one to replace it. So I’ve updated Ryan’s transcript to link to the new article.

In short, here are three fatal flaws discovered with the old legend:

1. We used to think Central Asian nomads searching for gold had come across the protoceratops bones. Yet gold has never been found near a protoceratops site.
   
   
2. Fossils typically just have a small bit protruding from the ground, and it looks very much like an ordinary rock to the inexperienced eye. To expose a whole bone in order to form the foundation of the folklore would have required a tremendous amount of work — not just work, but skill with handling fossil bones.
   
   
3. Griffin art is a poor match for protoceratops. Nothing that looks like a protoceratops fossil has been found in ancient literature, and art depicting griffins shows they were the size of a cat — which is hardly the impression you’d get if you were shown a protoceratops femur, nearly the size of a human’s.

Based on these and other details, it seems there’s just no way that actual history can support the hypothesis of early protoceratops fossils being responsible for griffin mythology.

And so we close another round of error corrections. Thanks to all of you whose submissions keep Skeptoid on the straight and narrow, and help it remain the valuable resource that it is. But please, give me a break just this once, and don’t bury me with corrections to the corrections? My belly is full of as much humble pie as it can hold.

By Brian Dunning
Follow @BrianDunning