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web

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I see a pattern here welcome stargazers

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Undine Rigas astronomer from the
 
Cincinnati Observatory

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and I'm James all very director the key
 
cassava pop planetarium in Gainesville

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Florida

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next week we get to experience the
 
second total lunar eclipse at the 2014

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2015 te trade

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you might be asking yourself what's a
 
tetrapod well

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they're very rare in this week's episode
 
will tell you why

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well also give you the lowdown on the
 
October 8th lunar eclipse

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let's show you here's how eclipses work

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celestial bodies cast to shadows a
 
darker

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inner shadow called the Umbra and a
 
lighter outer shadow called the penumbra

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your location with respect to the
 
shadows will determine the kind of

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Eclipse you can see

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the geometry of the lunar eclipse is
 
quite simple

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first the moon must be in the four-phase
 
putting

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earth between the Sun and Moon when
 
Earth Moon and Sun

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align perfectly we get a clips because
 
the moon's orbit is tilted by about 5

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degrees with respect to the Earth's
 
orbit around the Sun

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the earth Moon and Sun rarely align
 
however

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when they do the moon passes through the
 
earth's shadow says

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earth is so much larger than the moon
 
our entire shadow can cover the moon

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how high above or below the Earth's
 
shadow the moon passes

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determines the type a lunar eclipse we
 
can see if the moon only passes through

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the earth's penumbra

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we have what's called a penumbral lunar
 
eclipse this causes only a slight

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dimming up the moon is

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almost a noticeable to the average moon
 
watcher if only part of the moon passes

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through the

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Earth's ombra the darker inner shadow we
 
have what's called

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a partial lunar eclipse thus causes a
 
noticeable darkening

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obey portion on the moon surface however

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if the moon passes completely into the
 
earth number we have a total

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lunar eclipse now few members six months
 
ago

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we had a total lunar eclipse on income
 
tax day

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April 15 well it may surprise you to
 
know

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that there is an almost six months
 
pattern for clips is

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we call these eclipse seasons the moon's
 
orbit around the Earth is tilted

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appearing almost like a dinner plate
 
that is tilted with respect to a dinner

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table

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the points of intersection between the
 
moon's orbit in the plane of the Earth's

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orbit are called nodes

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if the New Moon and full moon occur when
 
the moon is that one of these nodes

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we get an eclipse as the Earth orbits
 
the Sun

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it carries them in with it these points
 
of intersection allow the Sun

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moon and earth to align it almost six
 
month intervals so for example

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in April 2014 the New Moon and full moon
 
were aligned with the Sun and her

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and we experienced a total lunar eclipse
 
and two weeks later

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there was a solar eclipse if we advance
 
time six months to October

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the New Moon full moon again the line
 
with the sign in earth

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and on October 8 we will see another
 
total lunar eclipse

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and two weeks after that on October 23rd
 
there'll be a partial solar eclipse

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although the six-month pattern eclipses
 
happens rather frequently

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it's rare that you get four total lunar
 
eclipse is in Iraq

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we call this a tetra at a tetrad is in
 
effect caused by the shape of the

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Earth's orbit around the Sun

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combined with the timing the clip
 
seasons and the sequence a tech trends

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varies over time

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for example between 1582 in 1908

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there were no te tracked but there are
 
17 tetrapod between 1909 and 2156

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the previous to trad occurred in 2003 24

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and the next to tread water current ill

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okay we've got our sky set up for
 
Wednesday morning October 8th 2014

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the mall enter the PIN number at 4:15
 
a.m.

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Eastern Daylight Time but you won't
 
notice anything exciting happen until

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almost 5:15 a.m. when the moon begins to
 
enter the number

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to tally begins at 6:25 a.m. Eastern
 
Daylight Time

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so if you happen to live on the east
 
coast the United States

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the moon will be setting just as
 
totality begins

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so you only get to see the beginning of
 
this eclipse

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however if you live near the west coast
 
you'll get to see the whole thing

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but don't worry stargazers since this is
 
a test trad you get two more

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opportunities to see a total lunar
 
eclipse

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we'll have another on April 4th 2015 and
 
the last thing will happen on September

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2050 all the lunar eclipses after that
 
will be either partial

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or penumbral you have to wait until 20
 
18 for the next total lunar eclipse

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so make sure you set your alarm clocks
 
and remember to

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keep looking up me