Ghost Peloton

For reasons which I suspect have more to do with wrangling Provinces than anything else, the Tour de France traditionally starts in another country entirely. This year: Yorkshire (which is a country, yes. Obviously).

To kick off the celebrations marking the event, this weekend saw a mad spectacle of an arts performance, Ghost Peloton. 36 illuminated riders choreographed to a backdrop of music and a film featuring more cyclists and dancers. It was glorious. You missed it, sorry.

Continue reading Ghost Peloton

The black holes have arrived!

A ball bearing illustrating the Schwartzchild radius of the Earth.
A ball bearing illustrating the Schwartzchild radius of the Earth.

I’ve ordered a handful of 18mm steel ball bearings for a demo that isn’t a demo, it’s merely a handling object, but handling objects can also have power and impact.

Hold out your hand and feel the weight of this ball on your palm. It’s pretty heavy. The metal is dense. Now imagine the impossible.

Imagine that all of this room is squashed and squeezed into the ball. It’s pretty tightly packed and much more dense. Now imagine the whole building is inside this ball. Hardly conceivable, but we’re not there yet. The stuff we’re made of contains lots of gaps – tiny gaps we can’t see, but gaps nonetheless. If all those gaps were filled in with more stuff we could squeeze even more mass into the ball. The whole city. The country. The entire world.

If the whole Earth, everything in it and everyone on it, were so densely packed that it could fit inside this steel ball, it would be a black hole. So dense that nothing could escape the pull of gravity.

It’s incredible how powerful something can be when brought down to an intimate, handle-able size.

The Earth has a Schwartzchild radius of 9mm. If the Earth was a black hole it would comfortably fit inside my wedding ring. That’s amazing.

Footnote: Please make sure you read Dave Ansell’s comment below. We’re not aware that any black holes the mass of the Earth exist. Black holes with larger mass would not need to be so dense.

Demos as political theatre

I’ve finally caught up with the BBC’s Challenger dramatisation of Richard Feyman’s last great adventure, which features this famous and terrific piece of science theatre. It’s sometimes referred to as an ‘experiment,’ which of course it wasn’t, really – the outcome was known and expected, and hence it’s a demonstration.

For our purposes, what it does rather neatly is illustrate the power of showing rather than merely telling, and remind us that such power is not limited to the realm of education. Challenger is plotted somewhere between a tense political stand-off and an engineering whodunnit, with Feynman’s famous O-ring demo as the climax. That a demonstration can serve such a rôle in a movie is something from which we should take heart. Sure, the circumstances were extreme, but if you ever find yourself doubting that demos can be dramatic: well, there’s a demo as the key moment in a drama. Appropriately enough for Feynman: QED.

Challenger is viewable on iPlayer for a few more days, and will doubtless be kicking around on torrent sites for a while longer, or if you’re not in the UK.

ISS Photography

Time was, if you washed up on a desert island and wanted to predict celestial events to avoid being turned into stew, you had to judge things just right so your preferred island happened to lie in the path of a suitable eclipse. Thanks to advances in technology, you can now predict much more frequent and widely-visible, albeit less spectacular, heavenly events. Like visible ISS passes, for example.

I took this photo from the bit of grass opposite my house in northern England, July 2010. It’s a one-minute exposure, and yes, that streak of light has people in it.