Why a few little sparks?

What am I doing

but striking a few little sparks

when what the occasion demands is a comet?

~ Seamus Heaney, interviewed in The Art of Poetry No. 75

 


Notes:

  • Photo: First photograph of a comet. Image obtained by Jules Janssen on June, 30, 1881 (via The Future of the Past)
  • Post Inspired by Maurice Vlaminck: “I seem initially to have followed Fauvism, and then to have followed in Cézanne’s footsteps. Whatever – I do not mind… as long as first of all I remained Vlaminck.” (via CozyHuarique)
  • Heaney Quote via Schonwieder

Miracle. All of it.

duck-cold-winter

A small child next to us looked down at her snow-covered boots, then pointed to a duck that stood on the ice on the bank and asked her mother an extremely good question: “Why don’t his feet get cold?”…

It’s this: The bigger the temperature difference between two objects when they touch, the faster heat will flow from one to the other. Another way of putting that is to say that the more similar the temperatures of the two objects are, the more slowly heat will flow from one to the other. And that’s what really helps the ducks. As all that frantic paddling was going on, warm blood was flowing down the arteries of each duck’s legs. But those arteries were right next to the veins carrying blood back from the feet. The blood in the veins was cool. So the molecules in the warm blood jostled the blood vessel walls, which then jostled the cooler blood. The warm blood going to the feet got a bit cooler, and the blood going back into the body was warmed up a bit. Slightly farther down the duck’s leg, the arteries and the veins are both cooler overall, but the arteries are still warmer. So heat flows across from the arteries to the veins. All the way down the duck’s legs, heat that came from the duck’s body is being transferred to the blood that’s going back the other way, without going near the duck’s feet. But the blood itself goes all the way around. By the time the duck’s blood reaches its webbed feet, it’s pretty much the same temperature as the water. Because its feet aren’t much hotter than the water, they lose very little heat. And then as the blood travels back up toward the middle of the duck, it gets heated up by the blood coming down. This is called a countercurrent heat exchanger, and it’s a fantastically ingenious way of avoiding heat loss. If the duck can make sure that the heat doesn’t get to its feet, it has almost eliminated the possibility of losing energy that way.

So ducks can happily stand on the ice precisely because their feet are cold. And they don’t care.

~ Helen Czerski, from “Why Ducks Don’t Get Cold Feet” in  Storm in a Teacup: The Physics of Everyday Life

 


Notes:

  • Image Credit: wsj.com – Agence France Presse / Getty Images
  • Inspired by Albert Einstein’s quote: “There are only two ways to live your life. One is as though nothing is a miracle. The other is as though everything is a miracle.”
  • Related Posts: Miracle. All of it.

Miracle. All of it.

comet-45p-honda-mrkos-pajdusakova

Comet 45P/Honda–Mrkos–Pajdušáková was first discovered 13 orbits ago in 1948 and has returned to the inner Solar System. It is physically ancient. It spends most of its time near the orbit of Jupiter and last neared the Sun in 2011. Over the past few months, Comet 45P’s new sunward plummet has brightened it considerably. The comet is currently visible with binoculars over the western horizon just after sunset, not far from the much brighter planet Venus. Comet 45P was captured last week sporting a long ion tailwith impressive structure. It will pass relatively close to the Earth early next month.”


Notes:

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