THE SOUTHWORTH PLANETARIUM
70 Falmouth Street      Portland, Maine 04103
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43.6667° N    70.2667° W  Altitude:  10 feet below sea level Founded
January 1970
2021-2022: LXXXVII "It is clear to everyone that astronomy at all events
compels the soul to look upwards, and draws it from the things of this
world to the other."  -Plato

THE DAILY ASTRONOMER
Monday, March 7, 2022
March 2022 Night Sky Calendar Part II


*FRIDAY, MARCH 18: FULL MOON*
Heavens, the many names that have been conferred onto winter's last full
moon. The "worm moon," in reference to the creepy crawlers burrowing their
way out of the thawing soil. The "sap moon," alluding to the seasonal flow
of tree fluid or also to those of us naive enough to expect spring-like
weather soon. Other seasonal full moon sobriquets include "the death moon,
" (ho ho ho), "Chaste moon," (I don't want to know) or the "Vernal equinox
moon," which, of course, makes no sense at all.

*SUNDAY, MARCH 20: VENUS AT GREATEST WESTERN ELONGATION (47 degrees from
the Sun) *
Greatest elongation marks the time when an inferior planet appears as far
from the Sun as possible in our sky. A planet appears in the eastern
pre-dawn sky at greatest western elongation and in the western evening sky
at greatest eastern elongation. This is definitely the best month of the
year to see Venus (See Planet Watch)

*SUNDAY, MARCH 20: VERNAL EQUINOX!! (GOLD EVENT!!!)*
*5:37 a.m. *
*SPRING IS BORN!!*
 The infant spring will  soon wail, run, and keep us awake with its
incessant noise making, while old man winter will be interred in a
neglected grave, much to our unbounded delight.    Astronomically, the
ascending Sun intersects the celestial equator today.     Throughout the
year, the  Sun appears to move along an undulating curve that alternately
descends below and then ascends above the celestial equator, the projection
of Earth's equator onto the sky.

To understand why the Sun appears to vacillate between a high and low point
during the year, we need to view our planet from a position outside its
orbit. Earth's axis is tilted relative to the vertical by 23.5 degrees.
 (See graphic below.)    As the planet revolves around the Sun, the
orientation of the Sun relative to the north and south poles is constantly
changing.   When Earth reaches the Summer (June) solstice, the north pole
is aligned as close to the Sun as possible.   Consequently, the Sun's
altitude above the southern horizon is highest.    Six months later, the
North Pole is aligned away from the Sun as much as possible and the Sun's
altitude is lowest.      Conversely, in June, the south pole is pointed
away from the Sun and in December, the south pole is aligned close to the
Sun.


*The revolving Earth.    If Earth were not tilted on its axis, the Sun's
altitude wouldn't change throughout the year.   However, Earth's axis is
tilted relative to the vertical by 23.5 degrees.  As Earth revolves around
its parent star., its poles shift alignments relative to the Sun.  In the
winter, the northern hemisphere points away from the Sun and in the summer,
the northern hemisphere is directed toward the Sun.       On both
the vernal and autumnal equinoxes, neither pole is aligned toward the Sun,
which shines directly on the equator.        Image:  National Weather
Service*

On the equinoxes, neither pole is aligned toward the Sun, which appears to
shine directly on the equator. This date is called the equinox, from the
Latin term "aequinoctium," meaning "equal night."   Because Earth is
neither uniformly dense nor perfectly spherical, the Sun doesn't fall on
the planet evenly and we will not have twelve hours of daylight on
the equinox.

*MONDAY, MARCH 21: VENUS AT DICHOTOMY*
Venus at what?
Venus at dichotomy: half lit, half dark from our perspective. Or, if you
prefer, a quarter Venus. Like all bodies in orbit around the Sun, Venus is
always half illuminated. However, we rarely ever see a half-lit Venus
because its orientation relative to Earth always changes. Look through a
telescope or binoculars at Venus today and you will see Venus as "D "
shaped.

*FRIDAY, MARCH 25: LAST QUARTER MOON*

*MONDAY, MARCH 28: VENUS, MARS AND SATURN WITHIN A CIRCLE 5.3 DEGREES IN
DIAMETER (SILVER EVENT!!)*
As we'll learn in the "Planet Watch" section, one will have to look into
the pre-dawn eastern sky to find planets this month. This morning one will
see Venus, Mars and Saturn "clustered" together. A beautiful sight for
those who love to observe planets.

*WEDNESDAY, MARCH 30: MOON NEAR JUPITER* One could almost consider this
event to be "academic." Academic events are either not visible or scarcely
visible. One will see the waning crescent moon (1% illuminated) close to
Jupiter very low along the eastern horizon. An observer MIGHT see these two
bodies this morning just before the brightening twilight obscures them, but
they'll both be difficult to see. Good luck!



PLANET WATCH

*A prefatory note:  *  All the visible planets are currently congregating
in the early morning eastern sky.

*MERCURY*
*Host constellations:  Early month - Capricornus; Mid month - Aquarius;
Late month - Pisces, then Cetus*
By virtue of its proximity to the Sun, Mercury always remains close to it
in our sky.  This month, Mercury inches closer to the Sun in the eastern
pre-dawn sky.   This fleet-footed planet flits swiftly between the morning
and evening skies.  For most of the month, it remains in the early morning
sky.  By the last week of March, however, it vanishes and will emerge in
the evening sky next month.  VERDICT:   Mercury watchers are accustomed to
frustration. However, to minimize that frustration, seek it out early this
month.

[image: McCoy_experiencing_cordrazine_frenzy.webp]
*WAIT A MINUTE!!  How can Mercury appear in the constellation Cetus?! Cetus
is not part of the zodiac!*
Oh, I was wondering if you'd notice that.    We know that the Sun can only
pass through the thirteen constellations comprising the Zodiac:   Pisces,
Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpius, Ophiuchus,
Sagittarius, Capricornus and Aquarius.   However, the planets, though
confined to a band centered on the zodiac, are not quite as constrained.
Planets can veer slightly away from the zodiac into adjacent
constellations.  In theory, according to Belgian astronomer Jean Meeus*,
planets can occupy 24 constellations.   Of course, most of the time, one
will find them in the zodiac patterns.


*VENUS: PICK PLANET!* *Host constellation Sagittarius - month's beginning;
Capricornus - starting from the month's second week*
A gorgeous sight for early risers! This Dantean sphere of flame and tumult
dazzles and delights in the eastern pre-dawn sky. Although Venus'
brightness dims slightly throughout the month (magnitude -4.4 on March 1;
-4.2 on the 31st), it remains an eye-pleasing spectacle for those intrepid
enough to venture outside before Sunrise. VERDICT: Who needs a warm bed
when you can stand before a pre-dawn goddess?

*MARS*
*Host constellation Sagittarius - month's beginning; Capricornus - starting
from the month's second week*
One must feel an immense amount of sympathy for Mars: the dim, awkward
older brother standing in the shadow of its brilliant and beguilingly
beautiful sister Venus. While Venus mesmerises the masses, Mars merely
exudes a moderately bright glow that commands scant attention. Of course,
through the month Mars brightens as it continues to draw closer to Earth.
(Magnitude 1.4 on March 1st; 1.1 on March 31st.) Despite this brightening,
Mars will appear about 130 times dimmer than Venus. VERDICT: Be a balm to
Martian feelings and give it a glance or two in those moments when Venus'
allure might wane.
*JUPITER*
*Host constellation: Aquarius*
Well, what can one say? After having served so dutifully as our evening sky
beacon, the giant Jovian has snuck behind the Sun for a well-deserved
hiatus. This bloated behemoth will insinuate itself into the pre-dawn
eastern sky toward month's end, but remain exceedingly difficult to see.
VERDICT: Breathe. Be one with Jupiter's absence. If you must behold the
behemoth, you might snatch a glimpse in the pre-dawn by month's end.
Otherwise, wait until April when Jupiter joins the morning sky throng of
planets.

*SATURN*
*Host constellation: Capricornus*
As you can probably guess, Saturn is also to be found in the early morning
sky. Though dimmer than Mercury and Venus, it shines a bit brighter than
Mars. The Ring Lord world tends to shine less brilliantly than the other
because of its distance. In fact, the mean distance separating Saturn and
Jupiter is about equal to the distance separating Jupiter from the Sun. The
gas giants have certainly been allotted ample amounts of space. VERDICT:
Seek out Saturn while you're admiring Venus, pretending to care about Mars
and trying to locate Mercury.


*Not to be confused with the Belgian ice hockey player of the same name.



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