THE SOUTHWORTH PLANETARIUM
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43.6667° N    70.2667° W  Altitude:  10 feet below sea level Founded
January 1970
2021-2022: CXLIV
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THE DAILY ASTRONOMER Tuesday, July 5, 2022
July 2022 Night Sky Calendar Part II

*WEDNESDAY, JULY 13: FULL MOON: SUPERMOON! (BRONZE EVENT!)*
Is it all just hype, this "supermoon" notion?    Isn't one full moon very
like another with little variation?  Not really.  A full moon that occurs
when the moon is at or near perigee, its point of least distance- appears
slightly larger (14%) and brighter than a full moon which happens when it
is at apogee -its point of greatest distance.    This month, the moon
reaches perigee at 5:04 a.m. EDT and will be full at 2:37 p.m.   EDT.

The image below reveals the size difference between a perigean full moon
(Super Moon) and an apogean full moon (Micro Moon.)    Were one to observe
these moons simultaneously, the difference would be readily observable.
However, any full moon looks essentially the same as any other....but,
they're not.

[image: 6a0105371bb32c970b01157127906d970c-640wi.jpg]

We have a nice assortment of July full moon names from which to choose.
"Thunder Moon," "Salmon Moon," and "Buck Moon," the last of which refers to
the antlers now growing out of the heads of male deer. Celtic names for the
July full moon include "Herb Moon," and "Mead Moon."

*FRIDAY, JULY 15: MOON NEAR SATURN*
Tonight, in the constellation Capricornus, one will see Saturn just north
of the waning gibbous moon (94% illuminated). One should expect to see
Saturn close to the nearly full moon as the ringed planet will be at
opposition on August 14th. (Refer to the "Planet Watch" section.)

*SATURDAY, JULY 16: MERCURY AT SUPERIOR SOLAR CONJUNCTION*
We recognize two different types of solar conjunction: *inferior
conjunction*, when a planet passes between Earth and the Sun and *superior
conjunction*, when the planet moves to the far side of the Sun relative to
Earth. Today, Mercury moves into superior solar conjunction and will then
reappear in the western evening sky later this month.

*MONDAY, JULY 18: MOON NEAR JUPITER *Tonight one will see Jupiter close to
the waning gibbous moon (69% illuminated). Both bodies will rise by 11:30
p.m. Jupiter passes just north of the moon within the constellation Pisces
the Fish. They'll both remain in the sky for the remainder of the night.

*TUESDAY, JULY 19: PLUTO AT OPPOSITION*
Yes, it's true. Pluto isn't visible without a telescope. However, the IAU's
dire 2006 pronouncement notwithstanding, Pluto is still a planet and
therefore its opposition is noteworthy. Tonight, Earth passes between the
Sun and Pluto. We should have placed quotation marks around the word
"between," (well, we did that time), because Earth will be 33.5 times
farther away from Pluto than it will be from the Sun. Pluto's distance from
Earth will approximately equal 3.17 billion miles.

*WEDNESDAY, JULY 20: LAST QUARTER MOON*
*THURSDAY, JULY 21: MOON NEAR MARS*
One will see the waning crescent moon (38% illuminated) close to the red
planet tonight within the region between the constellations Pisces the fish
and Taurus the bull. They'll both rise by 12:15 a.m.

*THURSDAY, JULY 21: THE HELIACAL RISING OF BETELGEUSE*
A new Betelgeusian cycle begins. Marking Orion the Hunter's eastern
shoulder, Betelgeuse serves as the winter sky's prominent red supergiant
star. For the last two months, this shoulder star has appeared so close to
the Sun in our sky that it hasn't been visible. This morning, Betelgeuse
appears for the first time -albeit briefly- since it vanished into the dusk
in late May. We refer to this date of reappearance as its *heliacal rising*.

Let's imagine that you served as a Betelgeuse watcher and your job required
you to track Betelgeuse each night. On July 21st, this star rises into view
just before the brightening pre-dawn twilight obscures it. The next
morning, Betelgeuse rises four minutes earlier, so you'll be able to track
it for a bit more than four minutes before it disappears behind the glow.
Like all non-circumpolar stars (those that rise and set), Betelgeuse rises
four minutes earlier each day as a consequence of Earth's revolutionary
motion. By May, Betelgeuse begins the night well over in the western
evening sky. On May 21st, it appears briefly in the west just as the dusk
twilight dims sufficiently to render it visible. Soon after its appearance,
though, Betelgeuse sets. The next night, Betelgeuse will set just before
the sky becomes dark enough to make it visible. May 21st is considered its
date of *heliacal setting*. It won't reappear again until July 21st, when
the next Betelgeuse cycle begins anew.

[image: Orion-Betelgeuse-Rigel.jpg]




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