Saturday: Listen,
do you want to know a secret? Do you promise not to tell? Whoa oh, oh. The
Beatles certainly didn’t write this song about the Barringer meteorite crater
in Arizona. Astronomers are studying this 50,000-year-old impact to learn more
about our planet’s violent history as well as the physics of impacts throughout
the solar system. If you’d like to be let in on some of these secrets, go to http://goo.gl/sqbBe.
Sunday: I
know you’re staying up late to train yourself to wait up for Santa. So look out
a south-facing window at 1 a.m. and see Sirius, the brightest star in the
nighttime sky, as high as it ever gets in the sky. It is two and a half fists held
upright and at arm’s length above due south.
Monday: Today
is Saturnalia, an ancient Roman festival in honor of their god Saturn, the god
of agriculture and time. The holiday featured a break from work and school, a
public banquet, and private gift giving. Some of these customs influenced the
secular aspects of Christmas celebrations. Celebrate Saturnalia at 6 a.m.-alia
by viewing the planet Saturn, two fists above due southeast.
Tuesday: Jupiter
is nearly two fists above the east-northeast horizon at 5 p.m. Wow – night sky
observations at 5 p.m. It must be getting close to winter.
Wednesday:
Venus is one fist above due southeast at 7 a.m. Even though the sky is fairly well
lit by the nearly rising Sun, Venus is bright enough to be easily seen. The
bigger challenge is Mercury, a half a fist to the lower left of Venus and just
above the horizon.
Thursday: Tonight’s
first quarter moon is in the constellation Pisces the fish.
Friday: At
3:12 a.m., the Sun reaches its lowest point in the sky with respect to the
background stars. This point is called the Winter Solstice. During the day that
the Sun reaches this point, your noontime shadow is longer than any other day
of the year. Also, the Sun spends less time in the sky on the day of the Winter
Solstice than any other day making this the shortest day of the year. Even
though it is the shortest day of the year, it is not the day with the latest
sunrise or the earliest sunset. The latest sunrise is during the first week in
January and the earliest sunset is during the second week in December. The Sun
is at its southernmost point with respect to the background stars on the day of
the winter solstice. This means the Sun spends the least amount of time above
the horizon on that day. But, the Sun rise and set time depends on more than
its apparent vertical motion. It also depends on where the Sun is on the
analemma, that skinny figure-8 you see on globes and world maps. During the
second week in December, the Sun is not quite to the bottom of the
analemma. But, it is on the first
part of the analemma to go below the horizon. During the first week in January,
it is on the last part of the analemma to rise above the horizon. For more
information on this, go to http://goo.gl/wE9nP.
The
positional information in this column about stars and planets is typically
accurate for the entire week.
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