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Oversky for November 2003: EXCELLENT ECLIPSE   Message List  
Reply | Forward Message #165 of 610 |
Oversky for November 2003: EXCELLENT ECLIPSE, MEDIOCRE
METEORS
Posted by Erich Landstrom, NASA JPL Solar System
Educator

The Moon is like a diva; if she’s not the star of the
show, then she upstages everyone else. This month it’s
especially true. There’s a total lunar eclipse at 8 PM
on November 8th, when the Moon changes colors before
our eyes. But then there’s the Leonid Meteor Shower on
November 18th, when there is so much moonlight, the
Moon will outshine all but the brightest meteors.

On Saturday, November 8th, North Americans experience
a TOTAL LUNAR ECLIPSE. Lunar eclipses occur whenever
the full Moon passes through the Earth’s shadow. The
shadow blocks most of the Sun’s light from reaching
it, but a little light, passing over the edges of the
Earth where sunrise and sunset is occurring gets bent
by Earth’s atmosphere in toward the shadow, making our
diva’s face flush. Luna’s Saturday evening performance
begins around 6:30 PM and ends around 10 PM. The Moon
begins entering the umbra (the darkest part of Earth’s
shadow cone) at 6:32 PM. The first blush starts on the
northeast corner, near the crater Pythagoras (I say
“corner” and “Pythagoras,” but despite popular
misconception, the ancient Greeks knew the Earth was
round and not flat thanks to eclipses. The shape of
curved shadow told them the Earth must be a sphere).
The Moon will be totally eclipsed at 8:06 PM, at
deepest eclipse at 8:19 PM, and will begin to exit the
umbra at 8:31 PM. By 10:05 PM, it will have completely
exited the umbra and be back to its usual frosty self.
To review: eclipse starts at 6:32 PM, totality between
8:06 and 8:31 PM, show over at 10:05 PM.

Each eclipse is unique in how the Moon reflects the
reds and oranges that tint the twilight sky during a
totality. Anything in the air – hurricane clouds,
volcanic dust, and forest fire ash – can affect the
eclipse’s coppery coloration, changing the Moon’s
muted grays in a range from dark brown to a freshly
minted penny. Astronomers use a five-point scale of
brightness (L = 0 being darkness and L = 4 being the
brightest) known as the Danjon scale to measure how
dark the shadow makes the Moon appear. The November
issue of SKY AND TELESCOPE magazine has more pertinent
information, or you can visit the website of the
essential magazine of astronomy at
www.SkyandTelescope.com/. This should be an excellent
eclipse.

But during November’s other great sky event, the Moon
spoils the show in the predawn morning of Tuesday the
18th. On November 18-19, the Earth transits though the
tail of Comet Temple-Tuttle. Plowing into the bits and
pieces of the comet's cloud of dust causes a
spectacular light show known as the LEONID METEOR
SHOWER, when the grit and gravel incinerate in the
Earth's atmosphere due to friction. Meteors are the
flashes of light caused by cometary debris hitting our
upper atmosphere and vaporizing (and phenomena related
to the ablation such as ionization). A combination of
the dusty debris crashing down at 71 km/sec, and the
relative velocities of the Earth, at a tangent heading
toward the constellation Leo, make the meteor shower
appear to radiate from the "sickle" of Leo the Lion.

The celestial fireworks show should be returning to
normal this year, producing 10-20 meteors per hour
after having storm-level displays of 1,000 per hour in
the last five years. But the Moon manages to upstage
the meteor shower, by being in the wrong place at the
wrong time. She positions her spotlight right in the
midst of Leo on the 17th and 18th, a fat waning
crescent phase that outshines the meteors and nearby
Jupiter. At best, this will be a mediocre meteor
shower.

LUNAR ALMANAC NOVEMBER 2003 (All times are Eastern
Time)
November 2 & 3: Moon by Mars
November 8: Full Moon (8:13 PM); total lunar eclipse
November 10: Moon at apogee (406,301 km); lower high
tides, higher low tides.
November 13 & 14: Moon by Saturn
November 16: Last Quarter (11:15 PM)
November 18 & 19: Moon by Jupiter
November 23: New Moon (5:59 PM); solar eclipse visible
over Antarctica and Australia
November 23: Moon at perigee (356,812 km); higher high
tides, lower low tides.
November 25: Moon by Venus
November 30: First Quarter (12:16 PM)
Tip: The full moon's diameter measures about 1/2 of
one degree in the night sky.

SOLAR ALMANAC NOVEMBER 2003 (All times are Eastern at
the 80 deg. N. longitude of West Palm Beach. Add 20
minutes to each time for each 5º west.)
November 1: Sun Rise: 6:29 AM EST, Sun Set: 5:37 PM
November 15: Sun Rise: 6:39 AM EDT, Sun Set: 5:29 PM
November: Sun Rise: 6:50 AM EDT, Sun Set: 5:26 PM
--------------------------------------------------------------------------------

PLANET PLACEMENT
VENUS (mag. -3.9) is caught in claws of Scorpius the
Scorpion, low in the west at sunset.
MERCURY (mag. -0.5) keeps close to Venus in Libra low
in the west after sunset.
MARS drops another magnitude (from mag. -1.2 to -0.4)
as it moves through Aquarius. Its ginger glow is
easily visible after sunset in the south, under the
“circlet” of Pisces.
SATURN shines (mag. -0.2) between the kneecaps of
Castor and Pollux, the Gemini Twins, visible high in
southwest at dawn.
JUPITER beams brightly (mag. -2.0) at the hind feet of
Leo in the southeast before dawn.
EARTH eclipses the Moon the night of the 8th, and
eclipses the Sun on the 23rd.

Join the "science giant" Erich Landstrom on SCIFI
OVERDRIVE radio program for science fiction, and
science fact stranger sounding than fiction. It’s like
Paul Harvey, with pointy ears. Listen to a broadcast
Monday mornings on the Business Talk radio network and
at www.scifioverdrive.com over the Internet!


=====
Erich Landstrom, NASA JPL Solar System Educator
Solar System Educators Program http://www.ssep.org
[Hands-on teacher training workshops sharing NASA's
missions of research, discovery and exploration!]

Science fiction & science fact stranger than fiction.
Listen Monday mornings on http://www.SCIFIOVERDRIVE.com

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Sun Oct 19, 2003 8:29 pm

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Oversky for November 2003: EXCELLENT ECLIPSE, MEDIOCRE METEORS Posted by Erich Landstrom, NASA JPL Solar System Educator The Moon is like a diva; if she’s...
Erich Landstrom
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Oct 19, 2003
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