Monday, May 21, 2012

Birding

I went to a retirement party the other evening for my good friend Dick Grant. Dick is a passionate birder and carver of bird sculptures, and he made a few remarks about birding. Of binoculars he said: "They not only let you see things better; they let you see things you didn't even know were there."

What a tiny little window it is we have on the world with our unaided senses. Natural selection endowed us with just enough perceptual apparatus as was appropriate to our size and needs. The needs for our survival as animals in the wild.

But Dick is not an animal in the wild. He has self-awareness, curiosity, and a keen sense of beauty. Binoculars extend his senses, open wider the window of the senses. He sees things that the rest of us don't even know are there.

Our eyes evolved to make use of available light, which was basically that part of the radiation of a yellow star that makes it through the Earth's atmosphere. But now we have climbed above the atmosphere, with instruments sensitive to parts of the electromagnetic spectrum that our eyes are blind to. We not only see better, we see things we never knew were there.

Consider the image above, of the Cygnus X star-forming region in the constellation Cygnus, made with the European Space Agency's Herschel Infrared Space Observatory (click, and again, to enlarge). A 3.5-meter reflecting telescope and instruments cooled to near absolute zero (so it won't be observing its own heat). A two-month journey to a gravitationally stable station around the second Lagrange point in the Earth-Sun system (far enough away from Earth not to be sensitive to Earth's own heat).

This is binoculars to the nth power.

How big a part of the sky? A dozen full Moons could line up across the image. A great window of the night through which we see with our unaided eyes only a sprinkling a stars.

The colors in the image, though beautiful, are false. What you are seeing here is heat from cool gases. Gases roiling and streaming as stars and planetary systems are born. 4500 light-years away in the arms of the Milky Way Galaxy. 500 light-years wide; the Sun and our nearest neighboring star Alpha Centauri are as far apart as those little pairs of bright spots on the right.

What a universe! In the heart of the Swan.