The first attempt at a rational explanation appears to

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Transcript The first attempt at a rational explanation appears to

Santa has 31 hours of Christmas to work with,
thanks to the different time zones and the
rotation of the earth, assuming he travels east to
west (which seems logical). This works out to
822.6 visits per second.
Visible sunlight is white. Most natural materials absorb
some sunlight which gives them their color. Snow,
however, reflects most of the sunlight. The complex
structure of snow crystals results in countless tiny
surfaces from which visible light is efficiently reflected.
What little sunlight is absorbed by snow is absorbed
uniformly over the wavelengths of visible light thus giving
snow its white appearance.
The winter solstice is the time when the Sun reaches it’s
southernmost rising and setting points in the northern hemisphere
and the Suns apex at noon is at it’s lowest point of the year. The
days are shortest and the nights are longest.
December 25th was the date of the winter solstice in the calendar
Julius Caesar devised for Rome in 46BC. Today the winter
solstice usually occurs on December 21st. Although Caesar used
a 365 1/4 day year, a year is actually a little shorter, and this
made the solstice occur a little earlier over the years. There was a
discrepancy of 1 day in 128 years.
It may be hard to believe, but electric Christmas lights have been
in use since the late 1800s. Martin Luther is credited with the idea
of putting lights on a tree. As he walked home one evening, he
was taken with the beauty of the stars seen through the
evergreens and he decided to replicate the sight by placing lighted
candles on his evergreen Christmas tree.
Three years after Thomas Edison invented the electric light bulb in
1879, his associate, Edward Johnson, put electric lights on a tree.
Then, in 1895, President Grover Cleveland set up a lighted
Christmas tree in the White House and the general public began
to notice. So began the tradition.
The first attempt at a rational explanation appears to have
been put forward by the German astronomer and astrologer
Johannes Kepler in the early 17th century.
Kepler, on observing a nova (exploding star) which was
visible in 1604, advanced the view that the Star of Bethlehem
may have been a nova occurring near a bright planet or
planets in conjunction (in proximity as seen from the earth).
Ginger has been used for thousands of years.
Greek bakers were making gingerbread more
than four thousand years ago (though probably
not in the shape of little men). Ginger's name
comes from a Sanskrit word meaning hornshaped (probably referring to the shape of the
root), but its distinctive flavor comes from
chemistry, from aromatic compounds called--what
else?--gingerols.
christmas colors in the sky
What is an aurora?
An aurora is a special interaction of three important features of
a planet: the atmosphere, the magnetic field, and the
surrounding space plasma.
Why are auroras different colors?
When plasma particles strike our atmosphere, they excite atoms into higher energy states. When
these atoms relax back to the lower energy state they emit energy in the form of light waves.
Different atoms are capable of emitting different wavelengths of light. For example, red and
yellow-green auroras are due to the relaxation of oxygen, while nitrogen is responsible for blue
auroras. Nitrogen may also emit red light, which is sometimes seen as the lower border of auroral
arcs.
Auroral spectra (color compositions) depend highly on the altitude at which they occur. Certain
altitude ranges are more conducive to the relaxation of specific atmospheric atoms than others.
(Auroras occur above about 90 kilometers.) For example, excited oxygen has more of a chance to
relax above 200 kilometers (where collisions are rarer due to low atmospheric density) so you see
red auroras higher in the sky.
Auroras are usually seen about 20 degrees from either
magnetic pole. The magnetic field lines that contact the Earth
there are connected to the processes that accelerate plasma
particles during the interaction of the solar wind with the
Earth's magnetic field. Since plasma must follow magnetic
field lines, most of this accelerated plasma reaches the
atmosphere at high latitudes.
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Where did the Christmas tree tradition originate?
Germany
Israel
New England
Scandinavia
What country did poinsettias originally come from?
The U.S.
Cuba
Mexico
Brazil
3. The candy cane legend says that it originated with a candy
maker from where?
A. Indiana
B. Mexico
C. Germany
D. Turkey
The reindeer is a hooved animal related to the other kind of deers lat:
cervus that can be found in most parts of the world, but not as closely as
a quick look at a reindeer might make one think since the reindeer in
some respects is unique. Most of the special characteristics have
developed as an adaption to the arctic and sub arctic, such as the broad
hooves which enable the reindeer to walk on and dig in deep snow after
food. The fact that some may fly is highly debated in the scientific world.