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:  2457741.16

               "Keeping a watchful eye on a complex sky"

THE DAILY ASTRONOMER

Wednesday. December 21, 2016

Finishing 2016

The DA is about to embark on an utterly undeserved vacation.  It is undeserved because we love astronomy with such a fanatical ardor that every day is like a vacation spent reclining next to a sea of mocha latte.     All the same, after today, the DA will go on hiatus until January 2, 2017! As we have almost 90 Pandora parchments left  to answer and nearly as many Messier objects  to visit before the school year slams to a shattering end in early August, we will hit the ground at a full sprint on 1-2-2017.

The last article of 2016 is devoted to the last of the noteworthy sky events of this most interesting year.      We can't truly count this post as a bona fide night sky calendar because it covers less than a week and we list only three events.   Two of them aren't even visible and one will prove exceedingly difficult to see!   So, we end on an ebb, but promise a lot more flow in the new year

TUESDAY, DECEMBER 27:  MOON 3.6 DEGREES NORTH OF SATURN

The very old moon (3%) hovers just north of Saturn in the eastern pre-dawn sky.  Saturn is just now appearing after its month-long absence.   Saturn is not one of the brightest planets and therefore not particularly easy to observe.    This morning, however, the waning crescent moon will guide you to find this magnificent ringed world as it slowly ascends against the twilight

WEDNESDAY, DECEMBER 28:   MERCURY AT INFERIOR CONJUNCTION

Do you remember the transit of Venus?   Strangely, even though it seems like it happened a decade in the past, it occurred May 9, 2016   At that time, Mercury  was also at inferior conjunction, meaning that it was between the Sun and Earth.   However, Mercury had just passed a "node," an intersection point between its orbit and Earth's.    Consequently, we could see Mercury crossing the Sun: an event called a transit.     This December inferior conjunction will not produce a transit, as Mercury will be nearly 2.5 degrees north of the Sun.    We won't see Mercury this week, but at least we'll now where it is!    (Note: the next transit of Mercury occurs on November 11, 2019)

THURSDAY, DECEMBER 29:  NEW MOON

New moon is also called "conjunction."  As is true with Mercury on December 28th, the moon will be between Earth and the Sun today.     When the moon is at or near a node during this conjunction, we;ll experience a solar eclipse.    NOTE:  We are already preparing for the "Great American Eclipse" on August 21, 2017.  While the Sun will only be partially eclipsed in Portland, the totality path will literally slice across the USA.     You will hear far more about this eclipse in 2017!

The DA concludes 2016 now and is anxiously awaiting 2017.

Thank you for subscribing to this service.   We hope you derive as much pleasure from reading these articles as we derive from sending them.

Thank you also for your feedback, your correspondence, your toleration for our errors, and for spending time in the DA classroom each day.

On behalf of everybody at the Southworth Planetarium, may you and yours enjoy a splendid holiday and may 2017 prove rich, sweet and bountiful.

Cheers!

Edward