Total Lunar Eclipse Over New Hampshire, September 27, 2015.
by Anura Guruge
As ever with any and all celestial events, I must, of course,
ADD “weather permitting” — especially in New Hampshire.
This, weather permitting, should be quite spectacular in that it is INDEED a TOTAL lunar eclipse.
So we will get to see the entire dramatic sequence
starting with the Earth’s shadow taking a BITE out of the Moon
all the way to the Moon being fully obscured …
to the Moon coming out of the shadow.
The only ‘sad’ thing is that it is going to be ‘late’ at night
— especially for kids.
Over New Hampshire the eclipse will start around 8:12 pm (Eastern).
But a total eclipse like this starts with the outer, dimmer shadow — the so called penumbra.
See diagram below.
The penumbra isn’t dark enough to take a bite.
All you will see is a shadow, that being what it is,
moving across the Moon’s surface.
The main shadow, the umbra, will touch the Moon at 9:07pm.
That is when the fun begins.
There will be a good sized bite by 9:25pm.
Half the Moon will be ‘eaten’ by 9:41pm.
Definitely worth keeping the kids up till at least 9:30.
The moon will be totally ‘eaten’ by 10:15 —
BUT maximum ‘shadow’ (darkness) will not occur till 10:47pm.
Then you get the whole sequence in reverse
with a half ‘eaten’ moon at 11:54pm.
It will be all done and dusted at 1:22 am.
A question that is bound to come up is “why don’t we have a total eclipse every month — at full moon?”
Makes sense. At full-moon, each month, we have the Sun —> Earth —> Moon alignment necessary for a lunar eclipse. BUT, we don’t get eclipses every month. At most, counting both lunar and solar eclipses, and partial eclipses as well as total, the maximum number we can have in a year is 7.
Why is that?
It all has to do with orbital inclinations. The orbit of the Earth around the Sun and that of the Moon around the Earth are not level — nor in a straight line. Both orbits are TILTED, i.e., inclined from ‘level’. So the bodies need to line up.
Get that. All to do with the 3 bodies rarely lining up.
We won’t have a total lunar eclipse in 2016. But in March 2016 we will have a TOTAL Solar eclipse!