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Subject:
From:
Edward Gleason <[log in to unmask]>
Reply To:
Edward Gleason <[log in to unmask]>
Date:
Wed, 28 Sep 2016 14:34:51 -0400
Content-Type:
multipart/related
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My apologies.
I have no idea why the article split itself into two parts.

E. G


​
*2.   Earth is farthest from the Sun in winter, which explains the coldness*

Actually, Earth is closest to the Sun during our winter.  We're farthest
from the Sun around early July.  Earth, like all the other planets in our
solar system, travels along an elliptical orbit.  Consequently, our
planet's distance from the Sun changes continuously.   Earth reaches its
greatest distance, aphelion, around July 4th and its point of least
distance, perihelion, around January 3.    At aphelion, Earth's distance
from the Sun is about 94.5 million miles.   At perihelion, the distance is
91.5 million miles.     Three million miles is quite a distance difference,
but it isn't enough to have much of an effect on our weather.


​Martian landscape.   Image: NASA

*3.  Mars is the coldest of the four inner planets*
This is probably the biggest surprise.  The coldest of the four inner
planets is Mercury, the closest planet to the Sun!     While the sunlit
side of Mercury bakes at about 800 degrees F, the dark side freezes at
temperatures around  -300 F!    Mars lowest temperatures, which occur
naturally at the poles, plunge down to about -225 degrees F.    Mercury
rotates very slowly, only once every sixty days.   So, its night lasts
about one Earth month long.  Mercury has no atmosphere to retain the heat
it absorbs during its long day, so it experiences extreme radiational
cooling.        Even though Mercury is much closer to the Sun than Mars,
Mercury's nights are long, dark and extremely cold.     Oh, and when the
Sun sets on Mercury, it goes dark almost instantly!

__________________________________________________________________
*FROM THE CATACOMBS OF INFINITE KNOWLEDGE*
*"The Goldbach Conjecture"*

Prussian mathematician Christian Goldbach (1690-1764) developed a
conjecture that now bares his name, "The Goldbach Conjecture."  It simply
states that

*"Every even number greater than 2 can be expressed as the sum of two
primes."*

For instance,    4 is the sum of the two primes,  2 and 2.
                           6 is the sum of 3 and 3
                           8 is the sum of 3 and 5
                          10 is the sum of 5 and 5

and so on.

While mathematicians have verified this conjecture for all even numbers up
to 40,000,000,000,000,000, they haven't proven it directly.     Verifying a
conjecture up to a certain value is not the same as proving it, because
mathematics is so tricky than a counterexample to this conjecture could be
tucked away quite far up the number line.    While Goldbach's Conjecture
could very well be true for all numbers, proving it has remained one of
mathematics' great unsolved problems.
__________________________________________________________________


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