THE USM SOUTHWORTH PLANETARIUM
207-780-4249 www.usm.maine.edu/planet
70 Falmouth Street Portland, Maine 04103
43.6667° N 70.2667° W
Altitude: 10 feet below sea level
Founded January 1970
Julian date: 2458638.5
"I'm a Fungi and people lichen me."
-Written on a T-Shirt and probably not taken from
"Women Who Run with the Wolves."
THE DAILY ASTRONOMER
Tuesday, June 4, 2019
June 2019 Night Sky Calendar Part II
MONDAY, JUNE 17: FULL MOON
Well, of course, June's full moon is called the "Honey moon." It's also
called the "Short night" moon as it tends to occur around the time of the
summer solstice. We also call this month's full moon the "Strawberry
Moon." Understandably, the full moon in June is associated with
flowers, fruits, honey, and all the signs of a warm, verdant world.
TUESDAY, JUNE 18: MERCURY 0.2 DEGREES NORTH OF MARS
We love it when planets come together. When planets come together,
however, the close proximity is just an eye trick. Mercury will be 85
million miles from Earth tonight, while Mars will be more than 232 million
miles from the Sun. Both worlds will be about 24 degrees from the
setting Sun in the western evening sky. Mercury will be the brighter of
the two. Mars will also exhibit a subtle reddish tint.
WEDNESDAY, JUNE 19: MOON NEAR SATURN
Some observers in southern most South America and Africa will observe a
lunar occultation of Saturn: the moon will appear to move directly in
front of the sixth planet. While we won't see such an occultation here,
we'll still observe the waning gibbous moon (95% illuminated) close to
Saturn.
FRIDAY, JUNE 21: SUMMER (JUNE) SOLSTICE! (GOLD EVENT!!!)
At 11:54 a.m. EDT on June 21, 2019, astronomical summer will begin! Summer
will end at 3:50 a.m. on Monday, September 23rd. As this event also
marks the beginning of astronomical winter in the southern hemisphere, the
proper name for today's event is the June Solstice. The word "solstice"
means, "sun still," as the Sun appears to linger around either solstice
point prior to changing direction.
[image: winter-summer-solstice-sites-in-greece-nasa-12-21-2005.jpg]
Over the course of a year, the Sun's rise positions vacillate between two
extremes, the winter solstice position in the southeast and the summer
solstice position in the northeast. The Sun rises due east on both the
vernal and autumnal equinoxes. Were we sufficiently patient and if we
had more than twenty clear mornings a year, we could follow the Sun's
progression by marking its changing rise locations. In the image above, we
see the difference between Sun rise positions from the perspective of a
town in New Mexico.
[image: 5b1978101ae66221008b4e23.jpg]
The Sun's position is always changing because our tilted Earth is
continually moving around the Sun. The graphic above shows Earth revolving
around the Sun (certainly not to scale!). During the December solstice,
the northern hemisphere is directed away from the Sun as much as possible.
During the June Solstice, our hemisphere is directed toward the Sun. As
Earth never stops in its motion, the Sun's rise and set positions are not
precisely the same on successive days. A small shift occurs. Around the
solstices, this daily shift is so small as to be barely perceptible, hence
the "Sun still" concept.
After today, the Sun's rise position will move southward until reaching the
winter solstice point on December 21 at 11:19 p.m. EST. The gradual
decrease in daylight duration will serve a sobering reminder of autumn's
inevitable arrival, just as the gradual increase of daylight throughout the
winter serves as a hopeful sign that warmer weather is only eight months
away.
SUNDAY, JUNE 23: MERCURY AT GREATEST EASTERN ELONGATION
It is a bit confusing at first: when an inferior planet (one closer to the
Sun than Earth) is at eastern elongation, it will be visible in the western
evening sky. When the planet is at western elongation, one will find it in
the eastern pre-dawn sky. Tonight, Mercury is about 25 degrees east of
the setting Sun and so will be somewhat easier to see in the evening sky.
Mercury can never venture more than 28 degrees from the Sun from our
perspective. Even when at greatest elongation, Mercury is still not an
easy planet to observe.
TUESDAY, JUNE 25: LAST QUARTER MOON
PLANET WATCH
MERCURY will be easier to see toward the end of the month, around the time
of greatest eastern elongation (June 23rd.) Look for Mercury in the
western evening sky! VERDICT: Best to wait until around mid month.
Although, one might want to catch a glimpse of Mercury on June 4th when it
appears close to the moon.
VENUS remains a pre-dawn eastern planet throughout the month. However,
this dazzling world will vanish in midJuly, only to return to the western
evening sky in September. VERDICT: one never wants to miss an opportunity
to see the brilliant planet Venus, even if it is low along the eastern
horizon.
MARS is about to leave the stage, as least for awhile. The red world will
vanish into the dusk by the second week of July. The fourth world will
remain out of sight until mid October, when it will return to the pre-dawn
eastern sky. Mars and Venus will be trading places! VERDICT: Mars
is slightly easier to see than Mercury, but only just. If you want to
see Mars, look into the western evening sky sometime during the first half
of June. Mars remains visible all month, but is easier to see in early
June than late June.
JUPITER (PICK PLANET!) We give Jupiter the crown because it will be at
opposition on June 10th. Jupiter will be visible throughout the night and
is at its brightest for 2019! VERDICT: A perfect time to behold the
behemoth world as it will be bold, bright, and up all night!
SATURN will likely be next month's pick planet as it will be at opposition
on July 9th. Presently, the Ring World rises in the early evening and will
remain visible for the rest of the night. Even though the rings aren't
visible with the unaided eye, Saturn is still a lovely celestial sight for
the sky watcher. VERDICT: While next month will be better for
Saturn watching, one will not have to stay up late to see the magnificent
planet Saturn.