The Moon, Earth's Shadow and Dawn

By the time I set up a refractor telescope, tripod and digital camera, it is 4:16 a.m. Saturday. No problem, I think, the partial eclipse is supposed to begin seconds before 4:17, according to a NASA web site. But the top of the moon looks darker. My first image, taken at 4:16, shows the moon’s north polar region is already several minutes into the shadow of our planet.

[One of more than 175 moon photos I took during the eclipse. This was shot at 4:16 a.m. I determined the moment by comparing the camera’s time stamp with the correct time on the Internet]

I stand on the sidewalk near our front lawn, peering at Luna between power lines. Because of trees and lines, my telescope will need to be moved several times in the next hour and a half, as the celestial show progresses.
The moon is brilliant silver with the dark splotch of the shadow, the umbra, at top. Below that splotch was a light brown curving region, almost like a mild tarnish, where the penumbra extends. The penumbra is a shaded swath surrounding the umbra.

It’s only about 13 degrees above the southwestern horizon. Much higher, to the southeast, Jupiter presents a mighty blaze. Almost all the stars have been effaced by the coming down.

The moon slides further into Earth’s shadow and the brown is darker, dramatically dimming the moonlight. It is en route to setting, by line of sight dropping ever deeper into the densest part of the atmosphere, so the additional miles of air pollution through which the light travels probably contribute to the darkening.

[The view at 4:22 a.m.]

I wish I had brought a folding chair outside. I could go in and get one. But I don’t want to miss any of the show by leaving the telescope for even a minute. And I might wake Cory.

A robin chirps and rechirps, seeming to evoke the morning. The neighborhood is growing a little lighter. There’s something magical about early dawn when the sun’s indirect glow is gradually brightening the land. The sun remains far below the horizon but it forms a brighter nimbus over the mountains to the east. More robins greet the day, joined by other songbirds. A neighbor’s car starts and he pulls into the street, heading toward the city.

This is a period I rarely get to enjoy, although I’m outside frequently enough at the time. When I’m in the desert with my main telescope I usually snooze from the end of astronomical darkness through the morning. I would have removed the finder and guide scopes, taken the cameras off, and taped on the telescope’s dust cover with electrical tape. I would have blocked the opening in the rear cell against dust, using a camera lens cover taped into place.

And I would be lying in the driver’s seat of our Jeep (seat pushed back and as flat as it can adjust) bundled in a blanket and trying to warm up. Maybe I’d have the engine running and the heater on, maybe also an oldies station on the satellite radio, before I switch off the motor and sleep. And I would have been too busy and tired to enjoy the dawn.

This morning, the weather is so warm that I take off my jacket and hang it on the porch railing. The curvature of the Earth is readily apparent in its shadow across the moon’s midriff. The ancients must have known the Earth is round, if they ever watched a lunar eclipse and understood what they were seeing. Or did they think the moon was a ball and the Earth a flat disk, so its shadow projected across the moon would be curved? Unlikely. They must have realized both are round.

[4:57 a.m.]

Around 5, the moon is a grungy crescent. Most of the surface is hidden by the umbra and the rest is a deep brown. The umbra covers the upper half, down past the craters Kepler and Copernicus, protruding into the Ocean of Storms.

I dramatically increase the exposure because the moon has lost so much light that it is almost invisible in the camera’s screen.

Now the morning is too bright for comfort. I can see homes and stores, intersections, trees and cars. I have shifted to our front yard and the telescope is pointing barely above the roof line of a house across the street. What if a policeman drives by and spots me? What if the paper delivery car pulls up? What if someone leaves that particular home for work? I imagine myself showing the officer my photos trying to convince him I’m not a Peeping Tom. An exhausted jogger in running shorts and T shirt drags past on the sidewalk, walking, his hands dangling.

[At 5:10 a.m. about as much of the moon is obscured as it will be during this partial eclipse]

I need to move again to aim at the target. I am on the sidewalk when the moon finally starts slipping below my view, a dark orange-brown swath wedged between a roof and a chimney.

[Last of the setting, eclipsed moon, between a roof and a chimney at 5:38 a.m.]

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