Skies partially clear for eclipse tonight

The early departure of rain from the North Bay on Wednesday and a partial clearing of local skies improves chances for seeing a total lunar eclipse Wednesday night, the National Weather Service said.

Conditions are a bit shaky, with partial cloudy skies expected, but “I think there might be a window - albeit a narrow window - for viewers of the eclipse,” forecaster Bob Benjamin said.

The next rain is not expected until Thursday morning, preceded by a cloud bank moving in late Wednesday - arriving after the eclipse, with any luck, Benjamin said.

“I think we might be just about right,” he said.

A lunar eclipse occurs when the sun, earth and moon align so that the earth blocks sunlight from reaching and reflecting off the full moon.

Wednesday’s eclipse is the last total lunar eclipse until Dec. 21, 2010.

The moon will move first into a partial shadow of the earth, causing a partial eclipse beginning at 5:43 p.m.

The moon will be in complete shadow - and thus total eclipse — from 7:01 p.m. to 7:51 p.m., when indirect sunlight filtered through the earth’s atmosphere will make it appear reddish.

The moon will then shift back into partial eclipse until 9:09 p.m.

The moon will be low in the sky, within about 20 degrees of the horizon, so astronomers recommend viewers watch from a hill or other high point with an unobstructed view of the eastern horizon.