You’ve no doubt seen the recent news about the discovery of a giant prehistoric claw, from a 2.5m sea scorpion (Jaekelopterus rhenaniae if you must know). BBC News has the full story, but suffice to say the creature evolved about 400 million years ago and probably lived in a river or swamp.

The find has led to speculation that ancient invertebrates were much larger than previously thought (something to do with elevated oxygen levels in the atmosphere). And there was me thinking that all those horrible insects in King Kong were just fantasy – watch this space for discoveries of giant ape jaw-bones.

In the meantime, here’s an animated version of the scorpion alongside a human – roughly to scale, though the human looks a bit confident for my liking.

When objects are drawn as overlapping in Moovl, then they are joined by invisible ’springs’. This is what the ‘tight-loose’ slider controls. Make the objects very ‘loose’ and the springs that join them together will be slack. Make the objects ‘tight’ and the objects will stick close together and interact strongly.

You can use this property to build visible ’springs’ by joining small objects together, eg small circles or triangles. Although clearly younger children need to explore the properties of springs using real objects, Moovl allows experimentation and prediction (Unit 3E: Magnets and Springs from the QCA Science Scheme of Work gives practical examples and activities).

In the drawings here I’ve used series of small triangles and circles joined together to form ’springs’. I think the ‘robot on a trampoline’ amply demonstrates my point…

Inspired by NASA’s recent spacewalk to repair the International Space Station I created a little Moovl experiment…

I created three identical men. Then I made the one on Earth quite heavy (for gravity) and quite sticky (to simulate air resistance). I made the one on the Moon lighter, and slippier. Then I made the one in space ultra-light and ultra-slippy.

As you would expect the Earthman managed a small jump, and came to rest quickly. The Moonman jumped higher and took longer to settle back down. And the spaceman… well, let’s just say I’m still looking.