Wednesday, January 5, 2011

A Swarm of Fireflies

Many a night I saw the Pleiads, rising thro' the mellow shade,
Glitter like a swarm of fireflies tangled in a silver braid.

- Alfred, Lord Tennyson, 1837-8, Locksley Hall

The Pleiades, about 425 light years away, are also called the "Seven Sisters" and were once used as a vision acuity test. How many individual stars can you see with the naked eye? The record is 18. I see no more than a fuzzy spot unless I turn slightly away and peer at them with peripheral version. Then I seem to discern individual stars.

 Last evening I walked outside at about 6:30 p.m. and thought I'd go into the backyard and view the Pleiades, one of my favorite celestial objects. But I did not have to leave the back porch. M45, as it is also called, had risen above the roof of the house, almost due east at that hour and I had the favor of the garage to block the wind as I gazed at this otherworldly sight.
 A telescope would be a great enhancement but having none I can draw the stars apart with the camera lens alone. The photo above is shown at a full 12 megapixels and this frame is cropped from the larger image. Amazingly, this technique brings individual stars into focus. In fact it also shows some of the intervening nebulosity of that cluster.
 I could have moved the camera beyond the tree but I though the branches added a nice contrast. Besides, the night was cold and I was content in the shadow of the garage. Why move? The spot was nearly perfect.

Here then is the entire frame. It's reduced, of course, to fit better on a computer monitor, but it shows the sky essentially as I saw it. The Pleiades are about midway across the frame and just above the dark roof, nestled in among the limbs.

 The second constellation I learned as a child was Orion. It is so obvious with its three-star belt. It is just below the Pleiades but still down behind the house. The first constellation I learned? The Big Dipper, of course. I can remember my grandfather pointing it out in Bear Lake, Michigan. "Follow those two stars to Polaris - the North Star," he'd say. And I could never be lost again, neither in the sky nor on the ground.
 What great signposts are these stars! Nearly constant, they are a great comfort to me on any clear night, winter especially, when I can step outside anywhere and be greeted by these old friends.