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Edward Gleason <[log in to unmask]>
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Edward Gleason <[log in to unmask]>
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THE SOUTHWORTH PLANETARIUM
207-780-4249      www.usm.maine.edu/planet
70 Falmouth Street     Portland, Maine 04103
43.6667° N                   70.2667° W
Founded January 1970
Julian date:  2457694.16

                   "Whatever it is, do it simply because you love it and
you'll do it forever. "





THE DAILY ASTRONOMER

Monday, October 31, 2016

Week 9 Night Sky Calendar:

October 31 - November 6, 2016



Halloween is a cross-quarter day, defined as a day approximately mid-way
between successive seasonal points.   The calendar recognizes four such
days.     Imbolc, or Ground Hog's Day (Feb 2), marks the mid point between
the winter solstice and vernal equinox.     Beltane, or May Day (May 1),
 is the cross quarter day between the vernal equinox and summer solstice.
 Lammas (August 1) is the CQ day between the summer solstice and autumnal
equinox.    Finally, Halloween, All Souls' Day or Samhain (pronounced
"Sow-en") is October 31/November, the cross-quarter day between the
autumnal equinox and winter solstice.


We have reached autumn's mid point and are bracing ourselves for winter's
arrival.     Despite the horrors of cutting winds and pelting ice that
attend the season, it does offer some pleasing aspects.   Principal amongst
these are the celestial sights we can now behold in the early evening.
Venture out this week and see the Pleaides Star Cluster poised on the back
of Taurus the bull.      Orion and his retinue of encircling creatures
(Lepus the Hare, Canis Major the Great Dog,   Monoceros the Unicorn, Canis
Minor the Little Dog) soon follow.     Meanwhile this week, one will see
the moon appear to pass close to Saturn, Venus and Mars.  The Equation of
Time reaches its annual maximum (we'll explain) and, of course, we turn our
clocks back to standard time on Sunday.




*Taurus and the Pleiades.**    Early this evening one can find Taurus the
Bull and the Pleiades rising in the eastern sky.  Even though we're still
in mid-autumn, the winter constellations are now rising in the early to
mid-evening.*






*MONDAY, OCTOBER 31:    VENUS AT APHELION*Planets follow elliptical, not
circular, orbits.   Therefore, a planet's distance from the Sun changes
constantly.    A planet veers from perihelion (its least distance) to
aphelion (its greatest distance).   Today, Venus reaches aphelion and will
be 67.7 million miles from the Sun.



*WEDNESDAY, NOVEMBER 2:   MOON 3.7 DEGREES NORTH OF SATURN*

This planet-moon appulse won't be particularly easy to see.  The waxing
crescent moon will be 8% illuminated and will set with Saturn soon after
astronomical twilight.    If you're seeking Saturn, you might want to look
into the western evening sky tonight as the thin crescent moon will help
you locate it.





*WEDNESDAY, NOVEMBER 2: EQUATION OF TIME IS AT A MAXIMUM FOR 2016*

The Sun appears to rise in the east, set in the west, and it reaches its
highest altitude, called "upper culmination," above the southern horizon.
   It is often said that the Sun reaches upper culmination at noon.
However, this statement is not precisely correct for most of the year.
Only on four days will the Sun be at upper culmination exactly at noon.
On other days, the Sun will either have already passed upper culmination by
noon or will not have yet reached it.    The amount of time separating
upper culmination and civil noon is indicated by the "equation of time"
chart featured below.   Here, "equation" means "correction."  When the
equation of time is zero, (April 15, June 12, Sept 1 and Dec 24), the Sun
reaches upper culmination at noon.   When the equation of time is positive,
the Sun will have reached upper culmination before noon.   When the
equation of time is negative, the Sun won’t have yet reached upper
culmination by noon.    Today, the Sun reaches its maximum equation of time
value (16.5 minutes). The Sun is at upper culmination at 11:43.5 a.m.

[image: cid:image002.jpg@01D1EFDE.8C95F0F0]

*Equation of time graph:**     The red curve indicates the 'equation of
time' throughout the year.   When the red line is below the mid-line
(0.00), the Sun has not yet reached the meridian at noon.  When the red
line is above the mid-line (0.00), the Sun reached the meridian
before noon.  When the red line is on the mid-line, the equation of time is
0.  For instance, on Feb 11, the equation of time is at a local minimum of
approximately -14 minutes.  On November 2, the equation of time is at its
maximum for the year of  16.5 minutes.      *


*THURSDAY, NOVEMBER 3: MOON 6.8 DEGREES NORTH OF VENUS  (BRONZE EVENT!)*Even
though we no longer send monthly sky calendars, we still confer "medals" to
the different events each month.   The most noteworthy event is the "gold
event," the second most noteworthy is "silver" and the third is
"bronze." (Events of extreme importance are labeled 'platinum.'  We don't
necessarily have a platinum event every month.)   We recognize that this
system is subjective and what's important to us might not necessarily be as
important to others.     This month's bronze goes to the moon-Venus appulse
this evening.  Seeing the crescent moon close to brilliant Venus is always
pleasing to the eye.   See these two bright worlds together tonight!


*SUNDAY, NOVEMBER 6, 2016:   MOON 5.3 DEGREES NORTH OF MARS*

The moon is 39% illuminated tonight and will be poised just "above"
Mars.     Although it is not as bright as Venus, Mars is not difficult to
find owing to its distinctive reddish hue.   One can easily locate Mars
tonight merely by first finding the waxing crescent  moon.


*SUNDAY, NOVEMBER 6, 2016:    REVERT BACK TO STANDARD TIME (PLATINUM
EVENT!!!!)*
Daylight Savings Time ends this morning at 2:00 a.m.     Set your clocks
back an hour.  Just remember the mnemonic "Spring forward, fall back).
Daylight savings time was devised by Benjamin Franklin to avenge the insult
of never having been elected president.   It is fortunate that we adjust
our clocks in this manner every spring to counteract the early morning
darkness. We will likely continue to retain the miracle of Daylight Savings
Time until some genius eventually invents electric lighting.

*PLANET WATCH*


*MERCURY (Host constellation:  Libra)*

Mercury is not visible until late November, when it will emerge in the
western evening sky.     Mercury passed into superior solar conjunction on
October 27th.  For three weeks following this conjunction, Mercury will be
too close to the Sun to be visible.     VERDICT:    Don’t bother to search
for Mercury until around Thanksgiving week, when it will high enough in the
west for viewing.  It will return just before Thanksgiving week, but will
be exceedingly difficult to observe.



*VENUS:  (Host constellation:   Ophiuchus)  PICK PLANET!*

As far as brightness is concerned Venus enjoys all the advantages.  Its
pervasive clouds reflect  about 67% of the sunlight it receives. It is
closer to the Sun than Earth, so the incidental sunlight is more intense.
It is also one of the closest planets to Earth, so the reflected light
isn't as diminished as it would be were it farther away.  Also, Venus is
almost as large as Earth, so its reflective surface area is larger than the
other two terrestrial planets, Mars and Mercury.     Venus is often the
pick planet because of these advantages.      Venus remains a bright beacon
in the western evening sky throughout November.    VERDICT:   Easy to see
if one ventures outside soon after sunset.  Venus is one of those celestial
bodies that appears during civil twilight.    Seek it out in the early
evening western sky.



*MARS  (Host constellation:   Sagittarius)*

Careful observers will notice something rather peculiar about Mars.    It
sets around the same time (9:30 p.m.) each night through November, just as
it did for most of October.   This occurs because Earth and Mars are moving
relative to each other in such a way so that Mars' position relative to the
Earth-Sun line remains the same…at least for now.         VERDICT:   Even
though it is nearly 100 times dimmer than Venus, Mars is still a conspicous
sight in the western evening sky.   It will also remain visible for about
two hours after Venus sets.




*JUPITER (Host constellation:  Virgo)*The second brightest planet, Jupiter
outshines all the night sky stars, but rises in the early morning eastern
sky.     In fact, Jupiter is currently the only visible planet in the
morning sky.    Jupiter rises a few minutes earlier each day and slowly
brightens throughout the year.    VERDICT:   If you're up before dawn,
treat yourself  to some delectable eye candy.    If you'd rather remain in
beautiful communion with your bed, you can wait to see Jupiter at more
decent hours later this winter.




*SATURN  (Host constellation:  Ophiuchus)*We lose Saturn just after mid
month.    One might observe the sixth world low in the southwestern evening
sky during the first three  weeks of November.    Otherwise, it will be
lost to sight.    Saturn passes through superior solar conjunction on December
10th and then will return to the pre-dawn eastern sky by late December.
VERDICT:  Try to find Saturn before November 23rd.  After that, wait until
the end of the year.


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