*THE SOUTHWORTH PLANETARIUM*




*207-780-4249 <207-780-4249>       www.usm.maine.edu/planet
<http://www.usm.maine.edu/planet> 70 Falmouth Street  Portland, Maine 04103
43.6667° N,                    70.2667° W Founded January
1970               "The Sun is middle aged and look how active it is!"*





*THE DAILY ASTRONOMERMonday, May 2, 2016 May 2016 Night Sky Calendar*


*Now, May begins!   Astronomically, we're entering the second full month of
Spring.   In New England, we're simply continuing to trudge through late
winter.     Of course, this month, the Mercurian transit is the big news.
We’ve been focusing on it ad nauseum for the last couple months and are as
giddy as a gadflys on green glens that this event is about to actually
happen.    If that transit is not enough to slack our astronomical thirst,
we'll also experience a Martian opposition, a meteor shower consisting of
Comet Halley fragments and the summer stars are rising as the winter
patterns exit stage west.*

*On occasion, we'll post a photo and caption of a constellation that is
either leaving or about to traipse onto our evening stage.  *


*Moreover, we're also posting Monday's "Daily Astronomer" on Saturday
evening, so it will be in your e-mail inboxes before we move into May.  *



*THURSDAY, MAY 5:  ETA AQUARID METEOR SHOWER PEAKS (BRONZE EVENT!) Remember
Halley's comet?   It is currently moving slowly away from the Sun, but will
turn around on December 9, 2023 in preparation for its 2061 return to the
inner solar system.   If you're not inclined to wait so long for its next
performance, you can at least see pieces of the famous comet!  The Eta
Aquarid meteoroids are fragments of Comet Halley suspended in space.  When
Earth ploughs through this stream, the particles descend through the
atmosphere and produce the lights we perceive as the  Eta Aquarid meteors.
These are so named as they appear to emanate from a point near Eta Aquari,
a star within the constellation Aquarius.    Eta Aquarid meteors and the
Orionid meteors (October) both originate from Comet Halley.  It might be
awhile before we see the most famous comet of them all, but at least we can
see pieces of it slicing through the sky tonight.   Expect 10 - 30 meteors
an hour, moving rapidly with persistent streams.   As the moon is almost
new, viewing conditions are favorable.*



*FRIDAY, MAY 6:  NEW MOON Beginning of lunation cycle 1155.*



*SUNDAY, MAY 8: MOON 0.47 DEGREES NNW OF ALDEBARAN We'll see Taurus the
Bull's alpha star very close to the waxing crescent moon.     On the other
side of the world, the moon will appear to "occult" Aldebaran.  An
occultation is the movement of a closer body directly in front of a more
distant one.     The moon can only occult four "first magnitude," (the
brightest) stars:   Aldebaran (Taurus), Antares (Scorpius), Regulus (Leo)
and Spica (Virgo)*


*MONDAY, MAY 9:  TRANSIT OF MERCURY (PLATINUM EVENT!!!!)*

*For those who've just joined, we assign celestial events "medals."  The
event we deem to be the month's most important event gets the "gold," the
second more important is "silver," and the third is designated "bronze,"
However, on occasion we will award the very special events the "platinum."
The transit of Mercury is just such an event.    For the first time since
November 2006, Mercury will appear to move in front of the Sun.    *


*The following is a time table of the event:*

*CONTACT I:                        7:13:29 a.m.              (The moment
when Mercury touches the Sun.  We then see Mercury moving in front of the
Sun.)*

*CONTACT II:                      7:16:41 a.m.               (The first
moment when Mercury is entirely visible against the Sun.)*

*GREATEST TRANSIT:      10:57:46 a.m.             (The moment when Mercury
is closest to the Sun's center.)*

*CONTACT III :                    2:38:05 p.m.             (The last moment
when Mercury is entirely visible against the Sun.)*

*CONTACT IV:                     2:41:17 p.m.              (The transit
ends.)*

*The next transit of Mercury occurs on November 11, 2019.*

*If you would like more information about this event, please consult the
Southworth Planetarium's "Transit of Mercury" module:
http://usm.maine.edu/planet/da-april-11-2016-mercurian-transit-module
<http://usm.maine.edu/planet/da-april-11-2016-mercurian-transit-module>*


*[image: cid:image002.jpg@01D1A2D1.991C5350]*

*Goodbye, Orion.    The giant hunter loiters over in the western, early
evening sky and by the middle of the month, will vanish in the twilight.
Expect Orion to return to the eastern, pre-dawn sky by early August*


*MONDAY, MAY 9:  JUPITER STATIONARY*

*Planets never stop!  Instead, a planet's migration across the sky will
appear to halt as a consequence of Earth's orbital motion.   A planet's
"prograde" motion is west to east.  Its "retrograde" path is west to east.
A superior planet -one that is farther from the Sun than Earth- will appear
to halt and then go retrograde prior to reaching opposition, when the
planet on the far side of Earth relative to the Sun.    The retrograde
motion will continue for awhile after opposition before the planet "halts"
again before resuming prograde motion.   Jupiter was at opposition on March
8th and, almost two months later, its motion will once again be west to
east.*



*THURSDAY, MAY 12:  MOON 4.7 DEGREES SOUTH OF BEEHIVE CLUSTER See the moon
less than five degrees south of Prasepe, the Beehive Star Cluster.     The
only prominent feature in Cancer the Crab, this star cluster resembles a
faint, luminous circle just to the east of Leo the Lion's sickle asterism.
 The moon will almost be at the quarter phase, so it will not wholly
obscure the star cluster.  *


*[image: cid:image003.jpg@01D1A2DB.F6655A70]*
*A close-up view of the Praesepe Star Cluster.  It is also known as the
"Beehive Star Cluster" as it resembles a bee swarm when observed
telescopically.*


*FRIDAY, MAY 13:  FIRST QUARTER MOON*

*FRIDAY, MAY 13: SUN ENTERS TAURUS*

*Now, spring begins in earnest. The westernmost of the winter
constellations is concealed by the Sun. Taurus the Bull is associated
mythologically with both the famous Minotaur and the bull that sired it.
The Sun continues its ascent into the sky  and will reach its solstice apex
within five weeks. Taurus is one of  the thirteen constellations through
which the Sun appears to travel each  year. The ecliptic constellations are
TAURUS THE BULL, Gemini the  Twins, Cancer the Crab, Leo the Lion, Virgo
the Maiden, Libra the  Scales, Scorpius the Scorpion, Ophiuchus the Serpent
Charmer,  Sagittarius the Archer, Capricornus the Seagoat, Aquarius the
Water  Bearer, Pisces the Fish and Aries the Ram. The Sun will enter
Gemini  the Twins on June 21st.*

*SUNDAY, MAY 15:  MOON 1.9 DEGREES SSW OF JUPITER (SILVER EVENT!!)*

*The gibbous moon joins Jupiter in the evening sky.  They will both set
after midnight.    One will have no trouble whatsoever finding brilliant
Jupiter poised "above" the gibbous moon tonight.     *


*WEDNESDAY,  MAY 18:   MOON 4.9 DEGREES NNE OF SPICA Spica, the alpha star
in Virgo the Maiden, is one of the four very bright stars which the moon
can occult (See May 8th).  Tonight, one will find the gibbous moon north of
Spica.   *


*See the moon to the north-northeast of Spica tonight.  Spica represents
the ear of wheat that Virgo holds in her right hand.  Virgo is the daughter
of Demeter (Roman: Ceres), the goddess of the harvest.  *



*SATURDAY, MAY 21:   FULL MOON*

*Today's full moon is a "blue moon," but not in the traditional sense.   By
convention, a blue moon is the second full moon in a single month.    We
know that there are not two full moons in May 2016.   However, this spring
we will have four full moons!   March 23, April 22, May 21 and June 20th.
(The June 20th full moon occurs less than half a day before the solstice.)
Most seasons have only three full moons.  However, in seven out of nineteen
years, a year will have thirteen full moons, so that one season must have
four.   This year, spring has four full moons.  The third of these four
seasonal full moons is called a "blue moon."   The first mention of this
definition was in a 1937 Maine Farmers' Almanac!    This full moon is a
"blue moon," but perhaps not the blue moon with which most people are
familiar.*



*SUNDAY, MAY 22:  MARS AT OPPOSITION (GOLD EVENT!!!)*

*We've been watching Mars growing brighter over the last couple of months.
Now, the red planet glows at its maximum brightness for 2016 as it moves
into opposition.   A planet is at opposition when Earth passes directly
between it and the Sun.   Around this time. the planet is at its closest
point to Earth.   Mars will actually be closest to Earth on May 30th, as
Earth is presently moving toward aphelion, its greatest distance from the
Sun.   Therefore, even after the opposition, Earth will continue to move
slightly closer to Mars.  By May 30th, Mars and Earth will reach their
minimum separation distance of 46.7 million miles.      As Mars is
comparatively close to Earth, it will appear as bright as Jupiter!  (For
more information, consult our "Planet Watch" segment.)*



*SUNDAY, MAY 22:  MOON 3.2 DEGREES NORTH OF SATURN*

*See Saturn and the waning gibbous moon tonight.  They'll rise in the mid
evening and remain visible all night.    Although Saturn won't be as
brilliant as Mars or Jupiter, it is increasing in brightness as it
approaches its June 3rd opposition.     *

*Now that May has arrived, the Summer Triangle will rise in the late
evening, just as Orion and his entourage set in the western sky.   The
Summer Triangle consists of the three stars  Deneb, Vega and Altair.  Deneb
marks the tail of Cygnus the Swan.  Vega represents the tip of Lyra the
Harp.   Altair is the eye of Aquila the Eagle.   *



*SUNDAY, MAY 29:  LAST QUARTER MOON*


*PLANET WATCH*



*MERCURY (ARIES-TAURUS) is not visible during the first half of May, except
for the May 9th transit.   During the second half of May, Mercury ascends
in the eastern early morning sky and brightens dramatically. VERDICT: Well,
if you miss seeing Mercury moving across the Sun's face, at least you can
observe it in the pre-dawn sky.    Best to wait until the last week of May.*



*VENUS:  Not visible.   While Venus does return to our evening sky in very
late July, one should wait until early August to find it.  VERDICT:   Well,
nothing to see here, we fear.*



*MARS: (PICK PLANET!)  (LIBRA-SCORPIUS)  The red planet glows bright this
month.  On the 22nd, Mars is at opposition and at its brightest for
2016.    By month's end, Mars rises around sunset and sets around sunrise.
  VERDICT:  This is the best time of the year to see our neighbor world!
Look up almost any time of night this month and Mars will likely be up
there somewhere.*



*JUPITER: (LEO)  Generally, Jupiter outshines all the planets, save
Venus.   By the third week of May, Mars is equally bright.   Jupiter sets
after midnight and remains a brilliant evening sky planet.    VERDICT:  The
giant planet is easy to see this evening and in the post-midnight western
sky.    Look beneath Leo and see Jupiter!*



*SATURN: (SAGITTARIUS) The most distant naked eye planet is growing
brighter this month as it approaches its June 3rd opposition.  Even though
it is fainter than Mars and Jupiter, Saturn is still conspicuous.  Saturn
rises in the early evening and will be almost at opposition by month's
end.  VERDICT:   Saturn is another easy planet to find. It won't dazzle you
like Jupiter or Mars, but will still be pleasing to the eye, particularly
if you have a telescope.*



*PLANETS IN ORDER OF DESCENDING BRIGHTNESS*



*MAY 1:*

*JUPITER - MARS - SATURN*



*MAY 30:*

*JUPITER/MARS (TIED) - SATURN - MERCURY*