Morning Moonset ‘Eclipses’ Eclipse – April 4 2015

If we take the definition of the verb form ‘eclipse’ to mean  ‘to block’, then we have the time and place set for our location in Mississippi Mills on the morning of April 4 2015. We didn’t get to see the very short umbral eclipse that happened this morning because the moon had already set:

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Moonset happens before Total Eclipse – courtesy Stellarium

 

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Eclipse plot courtesy Sky and Telescope

Here’s the situation:

 

As you can see from the lunar plot, the Total Eclipse portion (when the moon is entirely blocked by the earth’s shadow, the umbra  ) occurred at  11:54 UT or Universal Time. For Eastern Daylight Time we subtract 4 hours making it 7:54 am.  By then, the moon had set. Even the partial eclipse might have been difficult to view because the moon was close enough to the horizon to be blocked by terrestrial features.  You will notice also that the time for Total Eclipse is short because the moon is not aligned centrally in its passage through the umbral circle. It really traces a short chord. The moon’s orbit is inclined to the ecliptic by 5.14 degrees. So we don’t get a lunar eclipse occurring on every full moon. In this case, it was also a miss due to the fact that the moon was not high enough off the horizon at our location in eastern Ontario. One would have to be in a more westerly location to view the event.  For more information visit http://en.wikipedia.org/wiki/Orbit_of_the_Moon