Notes for Em


Time lapse of lightfoil in motion.I’m going to have to become some sort of physicist. Damn. I hate math.

No, actually, I don’t; I’m just a pathetic mathematician. Or, more accurately, not a mathematician at all. But that’s beside the point. Except, damn. I’m going to have to become some sort of physicist.

I suppose I shouldn’t be surprised. Some of the questions my brother and I asked thirty years ago probably astounded my father the way my daughter can absolutely befuddle me. “What,” she asked, not too long ago, “is a solar sail?”

Seven, by the way. Now eight.

Of course I told her about this far-flung idea of using a laser to push a spacecraft, and how the vessel could reach speeds near light. You know, stuff from fifteen years ago.

But I had no idea.

A BBC article brings me up to speed with lightfoil, which is a cool word despite the fact that no superhero will ever use it as a name:

Just as air causes lift on the wings of an aeroplane, light can do the same trick, researchers have said.

The effect, first shown in simulations, was proven by showing it in action on tiny glass rods.

Like the aerofoil concept of wings, the approach, published in Nature Photonics, works by making use of the radiation pressure of light.

The results are of interest for steering “solar sails”, a spacecraft propulsion based on the same force.

Each photon – or packet of light – carries its own momentum, and this “lightfoil” works by gathering the momentum of light as it passes through a material.

This radiation pressure has been considered as a fuel-free source of propulsion for long-distance space missions; a “solar sail” gathering up the momentum of the Sun’s rays can get a spacecraft up to a significant fraction of the speed of light.

But until now, no one thought to use the pressure in an analogue of an aerofoil, said Grover Swarzlander of the Rochester Institute of Technology (RIT).

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Cool science stuff


So, anyway, I was impressed over the weekend at how many people asked me whether I had heard about the octopus and the coconut. It’s one of those nifty things science brings us from time to time. Dr. Julian Finn, to the one, told BBC’s Rebecca Morelle he “nearly drowned laughing” when he first witnessed the behavior. But I admit I like Brendan Kiley‘s description for Slog:

An octopus goes for a walk.Octopuses continue their long tradition of freaking out human beings—now they’re using tools, excavating buried coconut halves (discarded by humans), tucking them under their … undersides, and “stilt-walking” them away to use as shelter ….

…. They escape from their aquariums, they grab birds from the land and into tidal pools, they solve puzzles, they recognize human faces, they occasionally attack divers, and now they build little houses for themselves.

Maybe the Haida were right all along: Octopuses are the people of the sea.

I just think it’s cool that we can add them to the list of tool-using animals. But, as with the crows, there is something a little unsettling about an animal that both uses tools and remembers who you are.

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Rumble in the deep? Fire down below?


Okay, so this is pretty cool. Jonathan Amos reports for the BBC:

Extraordinary video has been obtained in the Pacific Ocean of the deepest undersea eruption ever recorded.

The pictures show lavas bursting into the water at the West Mata submarine volcano, which is sited about 200km (125 miles) south-west of the Samoas.
The US Jason robotic submersible had to descend over 1,100m to acquire the high definition video.

The vehicle found microbes and a specialized volcano-dwelling shrimp thriving in hot, acidic waters.

“It’s an extraordinary environment,” said Joseph Resing, a chemical oceanographer at the University of Washington and the Joint Institute for the Study of the Atmosphere and Ocean in Seattle, US.

“You have molten lavas at 1,400C producing acidic fluids – the sulphur dioxide makes these fluids as acidic as pH1.4 – and yet microbes are thriving,” he told BBC News.

“The magmatic gases sustain and provide energy for microbial life, and then the microbes provide energy for the shrimp.

“We see them very close to the volcano – within metres.”

Dr Resing has been describing the volcano’s behaviour here at the American Geophysical Union’s (AGU) Fall Meeting, the world’s largest annual gathering of Earth scientists.

Not only is it the deepest eruption, but it is also among the hottest; the volcano, say researchers, expels boninite lava, which is apparently really hot.