Skyglow

1

Sometimes Leonard wakes me at two in the morning to watch the gibbous moon swallowed by Grouse Mountain. On winter nights, moonrise starts left of the butcher’s abandoned camper trailer where once this retired neighbor, vanished now, wiggled his ten blocky fingers at me and said, “Thirty years, and not a one lost,” his wife rolling her eyes beside him.

Leonard and I are only temporary here, too, sporadic suburban migrants who will drive hours past slow rivers of fly fishermen, their fly lines like gossamer against the rocks, and then climb the deep shadows of Rainbow Pass to alight for a few days at the rim of this small canyon someone long ago named Phantom, an Indian princess, Dark Flower, it’s said, still heard weeping—if we would only listen—for her dead betrothed.

According to The Bortle Dark-Sky Scale, a chart created to quantify the effect of light pollution on the “observability” of celestial objects, the darkest sky measured at zenith, the most direct point over our heads, is ranked Class 1.

“Theoretical,” the editors at Sky and Telescope call this sky. “An observer’s Nirvana.”

It seems that even at 9,600 feet altitude, even if our atmosphere were not a morass of human-made spill light and light trespass, the earth itself lights the visible sky with airglow, “planetary emissions.” Electrons lost in the ultraviolet of daylight recombine at night with oxygen and nitrogen atoms to create a green lambent halo from equator to pole, a halo so beautiful that one of the space station astronauts tweeted it to the unseeing world below.

To hope to see the faint and the far-flung celestial objects in the night sky, one must learn the art of dark adaptation, to quicken the sensitivity of the eye to the dim starlight that exists within this partial darkness. To hasten dark adaptation, you must use what’s called “averted vision” and look askance at the object so that its light hits the most sensitive area of the eye and, thus, becomes visible. The risk, though, is that the light might hit the “blind spot” where “the optic nerve” is said to “exit the eyeball,” and then, as if you were blind, nothing of the object will be seen.

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Finally, light shuts, the last of it caught in the long flat clouds at sunset that Mother calls “weird,” but now, one year after moving to Denver and 15 years after my father’s death, she adds the word “beautiful.”

“I’ve never seen that before,” she tells me. “All that gold light held in the clouds.”

My mother watches the sky from a ninth-floor apartment in the middle of a town turned bedroom community to Denver. At night the lighted town-scape I sometimes watch with her is a tatting of shielded luminaires and pole mountings, a river of headlights, and an orange skyglow of illuminated baseball parks.

The eastern sky from my mother’s window is a Class 7 on the Bortle Scale, suburban/urban transition, where the whole background of the night sky is a dim white, the Milky Way—that collective star glow that Leonard and I gaze at in the thin air above our mountain cabin—nearly invisible. The 110 deep-sky objects a French astronomer named Messier recorded back in the 1800s with the equivalent of a child’s toy telescope today have vanished from our sight. “Pale ghosts” is how Sky and Telescope describes what is left to see in this Class 7: diffuse nebular, globular, and galactic clusters of stars nicknamed Andromeda, Butterfly, and the Seven Sisters, and the Beehive Cluster, its starlight 400 million years old and traveling 577 years to reach us, only to be dimmed by our excess light.

Science also tells me that I can see 19 quadrillion (that’s 15 zeroes tacked on after the 19) miles or a little more than 3,200 light years away. Mother peers out her window when I tell her this and half-jokingly says this is not quite what she can see. Low-pressure glaucoma. Macular degeneration. [End Page...