Even if you never look at a calendar,
you can see that autumn is here just by looking at the angle of
the sun in the daytime sky. It rises a tiny bit lower each day,
no longer directly overhead at noon, as it is in summer. It is
now about halfway between the zenith and it's lowest point in
the sky, which it will reach at the winter solstice in December.
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Human beings,
vegetables, or cosmic dust, we all dance to a mysterious
tune, intoned in the distance by an invisible player.
Albert Einstein
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Also after sunset, one can see that summer is gone by the
constellations that are seen rising in the east. No longer are
the summer constellations
Cygnus, the Swan, and
Lyra, the Lyre, the
first ones to appear. By sunset now, they are directly overhead,
or even past zenith on their way down. The fall beauties such as
Andromeda and Persius are the first to rise in the east, soon
followed by Pleiades, Taurus, the Bull, and Auriga. If you stay
out past midnight, you will also see Orion, the Hunter, and even
Gemini, the Twins, some of winter's best.
Since the fall and winter
constellations and sky objects of interest will be just the same
as last year, instead of describing them all again, I refer you
to the
2007 Autumn Equinox Comet Hunter.
The only exceptions are the planets, which do change their
positions. See the
Sky Highlights section
below to find out which planets are visible this fall and where
to look for them. Instead, I would like to share with you a
silly, but [99%] true, little story about an amazingly lovely
phenomena that occurs in the night sky more often during this
time of year:
The Aurora Borealis.
Being a chemically injured female involved in a predominately
male hobby poses a few challenges for an amateur astronomer. But
on one cold October night some of those challenges actually
became a blessing.
Despite the cold weather, several
of us had gathered at our usual observing place in a state park,
hoping to see a predicted aurora borealis, often called the
"Northern Light." Since I do not reside in Alaska or Canada, an
aurora is a very rare treat.
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When the Sun shrinks to a
dull red dwarf, it will not be dying. It
will just be starting to live and everything
that has gone before will merely be a
prelude to its real history.
Arthur C. Clarke
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While waiting (and hoping for!) the aurora to begin, I set up a
telescope to have a look at Saturn. It was very beautiful, the
rings and several cloud bands in full view. After checking out a
few other favorite objects in the sky and walking around to take
a peek at what others were looking at through their 'scopes, I
was freezing, an of course, needed to use the bathroom badly. It
seems being out in the cold has that effect on gals, but not so
much on the guys! Having multiple layers and socks on, plus coat
and boots, I decided to do what I usually do, to wait as long as
possible. Soon we started to see some auroral activity in the
north sky. Our site was surrounded by trees, so we couldn't see
the sky down near the horizon, but there were some definite
shades of green and pink and purple visible in the sky between
and above the trees.
By this time I REALLY had to go! But being a female with all
those layers of clothing on it wasn't practical to just take a
walk in the woods like the guys do. It's very dark in those
woods and one little "mistake" could send me home - it was much
too cold be be . . . shall we say, "damp" and remain outdoors.
Being chemically injured, the Port-A-Potty was not usable
either; it always reeked of cherry air freshener, the kind that
would stick to the hair and clothing. Therefore, I have my own
little private spot - a picnic table right behind a huge tree
with a trunk much wider than me, to hide behind. The perfect
place to perch and carefully do what one must, well hidden from
the group. It is fairly far from our observing site though,
which is why I usually put off going there for so long.
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Lie on your back
and look at the stars.
Jackson Brown, Jr. (from Life's
Little Instruction Book)
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So I began the trek up a hill and
around a bend to my little spot at the top of the hill. Near the
hilltop there is a large open clearing. Once there, I looked up
and was greeted with the most spectacular aurora I had ever
seen! The sky was so beautiful it took my breath away. The whole
northern sky had become a glowing curtain of reds, purples,
pinks, blues, and greens. The colors were so bright, and
constantly changing, moving and there were numerous long
vertical pillars of shimmering ghostly white light dancing up
and down between the curtains of color. The sky seemed alive
with majestic beauty. The moment I caught my breath I started
yelling, "Hey guys, you gotta come up here now! You have to see
this!
Luckily they didn't hear me because
just then my Guardian Angel tapped me on the shoulder and said,
"Ahem! Don't you think you should do what you came up here to do
before calling the men?" Ah, yes, I had almost forgotten, and
there sat my picnic table and tree in plain view under that
brightly glowing sky.
Well, I got that problem taken care of as quickly as possible,
although it seemed to take forever, and hurried back down the
hill to get the group, since they were not able to hear me
calling to them.
Thankfully the aurora was still
going in all it's glory when we all got back up the hill.
Watching their faces the guys looked up in amazement was almost
as delightful as looking at the sky. Some had stopped dead in
their tracks the moment they saw the sky, mouths open in awe.
Once every one got their chins off their chests, we all began
talking in hushed, awed tones about the different colors we were
seeing, and about how some of the brighter stars could be seen
shining through the shimmering curtains of color and light.
Finally, the aurora faded away. On
the way back down the hill, one fellow turned to me with a
puzzled looked and asked, "Deb, how did you know to come up
here? We weren't seeing anything like that down at the site!" I
just smiled and shrugged my shoulders.
Another guy in our group had
brought his digital camera, and his photos of that aurora were
published in a national magazine.
The aurora borealis, or "Northern
Light" as it is often called, naturally are visible most often
in northern latitudes, nearer to the North Pole where they
originate. In places like Alaska and Canada, the are more common
sights that in the lower U.S. But that does not mean that you
won't be able to see one if you live in a more southerly
latitude. The aurora in my story was seen as far South as
Arizona, Texas, and Florida.
Auroras are caused by the increased sunspot activity and solar
winds. Where the sunspots are large or numerous, auroras are
also larger and cover more area of the sky. They are often
predicted about a day of so in advance by people who watch and
record the sun 's activity. Here is a great site that you can
check to see if an aurora is expected on any given night and how
far south it is likely to be visible.
Space weather and another website that
contains many gorgeous photos of auroras as well as links to the
best information about them is
Michigan Tech Aurora Page.
I can't promise that we will see an aurora south of Canada this
year, but we can keep our fingers crossed and hope that the sun
is busy making one for us. The aurora in my story occurred in
October of 2004 and was followed by an even more spectacular one
in November. I haven't seen one like those since so I think we
are due one. :-)
Sky Highlights:
Meteor Showers
Orionids - October 2 through November 7 peak -peak October 21,
around 4am.
radiant - near left shoulder of Orion caused by Halley's comet
rate - 10-15 per hour
Leonids - November 14-21 peak- November 17, near dawn
radiant - constellation Leo caused by- comet Temple - Tuttle
rate - variable, much lower in recent years then previously
Geminids - December 7- December 17
peak - December 14, around 2 am radiant - constellation
(Gemini caused by - an object named
3200 Phaethon, believed to be an extinct comet rate - 120 to 160
per hour)
note: if you will only watch
one meteor shower this year, the Geminids is the one to pick.
They are usually bright yellow in color and have long trails.
They are also a little slower morning than many meteors, making
them easier to catch sight of. The show starts early in the
evening, as soon as Gemini is up. This will likely be best
meteor shower of the year.
Ursides-December 17 through December 26 peak - December 22
radiant - Ursa Minor - the Little Dipper rate - 1- per hour
Explanation of Terms:
peak - the night/morning and
approximate time when the highest number of meteors can be seen.
Dates given begin at midnight
radiant - the area of the sky from which the meteors
appear to come.
caused by - the object, usually a comet, whose debris
that earth passes through during the shower. The pieces of
debris burn up once they enter the earth's atmosphere. This
burning debris is what we see as "shooting stars."
rate - the maximum number of meteors that it is possible
to see during the peak night/morning. Keep in mind that the
rates given are for perfect conditions - no clouds, no moon, and
very dark skies.
Moon Phases
New Moon - November 27, December 27, January 4, January
26 February 25
First quarter - November 6, December 5, January 11,
February 2, March 4
Full Moon - November 13, December 19, January 18,
February 9, March 11
Last (3rd quarter) - November 19, December 19, February
16, March 18
Mercury- look to the east near the horizon around 5 am in
October and November. Mercury will look like a tiny red star,
but doesn't twinkle and has a distinct rusty red color, similar
to Mars.
Venus - Very bright yellow, the brightest "star" in the
sky. Look for it low in the western sky at dusk. It will be in
the constellation Capricornus during November. Venus will
visible in the early evening throughout fall and early winter,
it will be higher in the sky and stay up longer and longer as
fall progresses.
Mars - Look for this bright rusty red planet in the
constellation Ophiuchus during November. You can see it setting
low in the western sky, below Venus until the end of November
around dusk.
Jupiter - Look for this bright yellow or white planet in
the constellation Sagittarius, low in the southwestern sky. It
is almost as bright as Venus. Jupiter will be visible from dusk
till it sets in the west around 6pm in December.
Saturn - Look for Saturn in the constellation Leo as it
rises in the east. It will rise a tiny bit earlier each night
through fall and winter, and so by the end of November it will
rise by around 1 am and closer to 10 pm by the end of December.
Conjunctions
November 30 - Jupiter will be just 2' [degrees] to the upper
right of Venus tonight, that is the width of 2 full moons. Look
for the pair of planets low in the western sky around 7 or 8 pm.
Comet Hunter is an
avid astronomer who has courageously coped with chemical injury
for many years.
Email Comet Hunter your
star gazing questions.
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