(MTN News-Helena)  Eagle eyed sky watchers, set your alarms early on Wednesday morning, as a “penumbral” lunar eclipse will slip across the sky.

In this week’s weather wise, the changes to the moon will not be as prominent as a typical lunar eclipse.

Look at the full moon on Wednesday morning, and you may notice that it is slightly darker than a normal full moon.  Observant people will recognize the shadow, while other’s won’t spot anything at all.

This is a different type of lunar eclipse, called a penumbral eclipse.  In this setup, only the outer shadow of the earth is cast over the moon. This eclipse is much more subtle, and much more difficult to observe than either a total or partial eclipse of the moon.  There never is a dark bite take out of the moon as in a partial eclipse.  This eclipse will never progress to reach the dramatic minutes of totality.

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At best, at mid eclipse, very observant people will notice a dark shading on the moon’s face.  35% of all eclipses are penumbral, another 30% eclipses are partial, and the final 35%  go all the way to becoming total eclipses of the moon.

So don’t expect  the moon to become blood red when a total lunar eclipse occurs.  However, in the early morning hours on Wednesday, beginning around 4:00 am, peaking at 5:47 am, and lasting until the moon sets, some of you may recognize the subtle and still cool coloring of a full moon in the outer shadow of the earth.


Reporter: Curtis Grevenitz