Magnetic field of the Earth

One of the labours of Hercules was surely to find a map of Earth’s magnetic field.

There’s no shortage of crude diagrams of bar magnets superimposed over cartoon globes, and plentiful plots of isogonic lines to be procured from multiple perspectives; yet for accurate depictions of the simple lines of magnetism over Earth’s surface, the offerings seem sorely slack. So just imagine how hard that would have been two thousand years before the internet.

The most common chart I see that has an actual connection to reality, is a map of isogonic lines – contours of equal magnetic …

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The origin of oxygen

There’s a bit of a persistent rumour getting around on internet and extranet circles. Actually far too many, but today’s lucky topic is the notion that plants produce oxygen from carbon dioxide.

It’s a simple enough story. We know that photosynthesis consumes carbon dioxide, and produces surplus oxygen. Since CO₂ quite obviously contains O₂, well, there’s not even anything to question.

Except that photosynthesis has a few more aspects than just these two gases, and the whole system isn’t an atomic process.[1] Fortunately you don’t need to be within arm’s reach of …

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The packaging hypothesis

Let’s suppose you have a box. Ideally this is no mere supposition but you actually have a box nearby right now. If you don’t, you’ve surely had one at some point, so in that case we’ll talk about that box.

Boxes are made for storing things. You can put all sorts of things inside your box. You could even put another box inside it.

And you needn’t stop there. Another box can go inside your boxed box, or you could even put multiple boxes alongside each other inside the original box. All manner of boxes …

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Capricorn leaves capricorn

27 May marked a momentous Monday for people who ascribe significance to the interval between 22 December and 19 January everywhere, as it was on this day that Capricorn left Capricorn.[1]

“What?”

For those suitably stocked up on the applicable jargon, it was on this date that the point on the ecliptic with right ascension 20h referenced to B1875, and demarcating the western edge of Capricornus, now has an ecliptic longitude greater than 300°. Armed with this knowledge, you can go do something else now.

“Huh?”

Okay, so we need to step back a bit. Then step back another …

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What’s great about Xiphosura

In the last few years I’ve moved more and more towards theming my general online presence around horseshoe crabs. There’s a general reason for that, and to properly honour horseshoe crabs for what they are, it deserves to be explained.

First, we have to start at the beginning. Or, the best we lesser specimens can know of the beginning. Back around the late Ordovician, at least 445 million years ago[1], there was a chelicerate currently called Lunataspis, which looked something like this:

stippled drawing of an animal with a flat, round body and narrow tail

Reconstruction of external exoskeletal morphology of Lunataspis aurora. Figure 5 from [Rudkin2008].

Fast forward 445 …

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A new, (pseudo-)static site

It’s been a long, long time coming – years, really – but at long last I have a site I can maybe take enough pride in to use seriously and keep everything together. At least, theoretically; because strictly as I write this the site for it to appear on does not quite yet exist. I have spent weeks on development and testing though, with uncharacteristic productivity, so it should be all ready to go live more-or-less pending only these words.

For a while I’ve wanted to bring my various shenanigans together in a unified site that would present it appropriately …

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Limulus lotus

It’s no secret that I like and respect horseshoe crabs – for reasons that deserve to elaborated on some time. So when someone shared this CRABTCHA, I had no choice but to respond “Front and centre where it belongs 🧘‍♂️”

Happy World Ocean Day now prove you are not a robot.

(This CRABTCHA is brought to you by @jopabinia.bsky.social and yours truly.)

spoof captcha telling people to click on images containing crabs, but the images are of various true crabs and false crabs

franz

To which came the response “I'd like to see a horseshoe crab attempt a lotus position.”

Well, challenge accepted.

A horseshoe crab on a sandy surface, with its body upright. Unless someone told you, you wouldn’t notice the lowest pair of legs are crossed.

Phone picking

Lockpicking a phone through the USB port

How to unlock a phone

A silly idea I’d had for a while, made manifest over the Easter weekend.

This particular picture holds the dubious honour of being suspected to be “AI art that somehow knew how to make hands.” Or “probably traced off a real image.”

I confess – as a possessor of two hands, I did dare to glance at them a few times throughout.