THE SOUTHWORTH PLANETARIUM
70 Falmouth Street      Portland, Maine 04103
(207) 780-4249      usm.maine.edu/planet
43.6667° N    70.2667° W  Altitude:  10 feet below sea level Founded
January 1970
2021-2022: CXVIII
"There is no greater agony than bearing an untold story inside you."
-Maya Angelou

THE DAILY ASTRONOMER Wednesday, May 4, 2022
May 2022 Night Sky Calendar Part II


Named after Maia, the Roman goddess of growth, May marks the last full
month of spring. (Up here, it marks the first half month of spring.) As we
learned yesterday, the month of May ushers out the winter constellations
while drawing the summer constellations into greater prominence. In other
celestial matters, May 2022 will bring us the Eta Aquarid meteor shower, a
gathering of the moon, Mars and Jupiter, and, of course the TOTAL LUNAR
ECLIPSE on the night of May 15/16. As you might expect, this last event
will take up most of the oxygen in this first part of the May 2022 night
sky calendar.

*FRIDAY, MAY 6: ETA AQUARID METEOR SHOWER PEAKS*
Only active around the first week in May, the Eta Aquarid shower produces
about 40 bright, fast meteors at its peak. Although it is not considered a
major shower, the Eta Aquarids are noteworthy because of their progenitor
comet: none other than the famous Halley's Comet. When one observes such a
meteor, one is watching a fragment of Halley's Comet perish in a spasm of
light. The best time to watch for this meteor shower is after midnight, the
time when our part of the planet is turning in toward the densest part of
the meteoroid stream.
Fortunately, the waxing crescent moon (28% illuminated) will set at 10:46
p.m. that evening.

*SUNDAY, MAY 8: FIRST QUARTER MOON*

T*UESDAY, MAY 10: MOON NEAR REGULUS*
[image: qRrdXLHgSrmtVB46miY5cC.jpg]
One will see the waxing gibbous moon (66% illuminated) close to Regulus,
the brightest star in Leo the Lion.   The moon will appear to move to the
north of this star.

*THURSDAY, MAY 12, 2022: BRILLIANT ISS FLY-OVER*
The International Space Station will pass almost directly overhead on the
morning of May 12, 2022. The chart below shows the ISS path through the sky
during this "fly-over" event.
[image: PassSkyChart2.png]

*Time-table:*
4:21:50 a.m.    The ISS rises WNW
4:27:16 a.m.    The ISS attains its maximum altitude of 82 degrees.  At
this time, the ISS will also attain its maximum brightness of magnitude
-3.9: just about as bright as Venus!
4:32:40   The ISS sets  SE.

Although we'll see the ISS fly over dozens of times in May 2022, the May
12th early morning fly over will be the brightest of them all!
*SUNDAY, MAY 15, 2022: TOTAL LUNAR ECLIPSE (PLATINUM EVENT!!!!) *Tonight,
the full moon will move through the inner part of Earth's shadow, a dark
region known as the* umbra. *

[image: 320px-Lunar_eclipse_chart_close-2022may16.png]
First, the eclipse will occur on the night of May 15th. Actually, it will
begin on May 15th and end on May 16th. Refer to the time table below.

*May 15 - 9:32 p.m. PENUMBRAL ECLIPSE BEGINS*
Earth's shadow is divided into two regions: the light, outer part
of Earth's shadow, called the 'penumbra,' and the inner region called
the 'umbra.' The penumbral eclipse begins when Earth first touches
the penumbra. The moon passes completely into the penumbra before it
reaches the umbra. Honestly, unless you're one of those mystical poetic
types who can actually tell the difference between a whisper of a breeze
and a caressing zephyr, you won't notice much during the penumbral part of
a lunar eclipse. Perhaps the brilliant moon's pallor is rendered a
few phantoms less vibrant, but even that is a stretch.

*May 15    -    10:27 p.m. PARTIAL ECLIPSE BEGINS*
This is when the 'action' starts. The umbra is the dark interior shadow.
Once the umbral eclipse begins, we'll see Earth's curved shadow against the
moon. We'll watch the shadow migrate across the moon until the moon is
completely immersed in Earth's shadow.

*May 15    -    11:29 p.m. TOTALITY BEGINS*
Totality begins when the moon is completed inside Earth's umbra. The moon
will not be wholly lost from sight. Instead it will appear reddish, because
Earth's atmosphere scatters blue light, but directs red light into its
shadow. (We see a blue sky during the sky because of this effect.) The
eclipsed moon will reflect this reddish light back to us, producing the
ominously named 'blood' moon. One effect that we think is absolutely
magnificent is the 'spherical moon' phenomenon. During totality, the color
differential across the moon's facade lends it a spherical appearance. The
moon actually appears as a crimson sphere in space, as opposed to the full
moon's usual disc-like appearance.

*May 16    -    12:11 a.m.   MAXIMUM ECLIPSE*
When the distance separating the center of the shadow and the moon's center
is at a minimum.

*May 16   -   12:53 a.m.       TOTALITY ENDS*
At this moment, the moon starts its exit from the umbra.  We will see a
thin sliver of the moon emerging from the inner shadow.

*May 16  -    1:55 a.m.    UMBRAL ECLIPSE ENDS*
For all intents and purposes, the show is now over.  The moon completely
leaves the umbra and appears, well, like a full moon again, except that it
remains immersed in the penumbra.

*May 16 -    2:50 a.m.    PENUMBRAL ECLIPSE ENDS*
The eclipse event is now technically over.  Of course, the moon's
brightness is hardly diminished during this last hour because the penumbra
is so faint.

Part III tomorrow
___________________________________
In honor of May 4th day:
STAR WARS ASTRONOMY

A LONG TIME AGO IN A GALAXY FAR, FAR AWAY
This famous opening line prompts the question:  could alien life have
existed a long, long time ago?   We know that advanced life forms cannot
exist without an abundance of complex molecules that, themselves, are
composed of "heavy elements," such as oxygen, phosphorous, carbon, and
others.*      Only the simplest elements, primarily hydrogen and helium,
existed during the Universe's infancy.     The first generation of
stars manufactured
the "metals," defined astronomically as the elements heavier than helium.
These stars, being the highly massive population III, would have exploded
as supernovae, thereby enriching the galaxy with an infusion of all the
heavy elements.     This chemically rich material would have then become
incorporated into other star/planet systems. On these heavy element laden
planets the first life might have developed. The life might have evolved
from the simplest prokaryotic cells to a galaxy-dominating empire. We
assume, based on Earth's evolutionary time frame, that such a process would
have required at least five to six billion years.   As humans haven't yet
become a star faring race, we haven't the faintest idea how long such a
progression would require.   After all, humans haven't yet ventured more
than a quarter of a million miles from Earth. We're a long way from zipping
between star systems.

The upshot of it all is that the Universe might well have produced mighty
empires in distant galaxies that have long since vanished.  We can't know
if they existed, of course, but we can at least be confident that the
necessary chemical building blocks have existed in the cosmos for billions
of years.

The assumption we've made is that we're actually now observing the "Star
Wars" galaxy as it was when all that transpired on film was happening.   If
it all occurred a billion years ago, the galaxy is a billion light years
away from us.    Then, again, there is a slight possibility that we're over
thinking it.


LASER GUNS
As impressive as these weapons appear, we certainly hope they weren't
expensive, because they truly don't work well.     Let's assume you are
surrounded by a doom of storm troopers,** but, fortunately, you're armed
with a laser gun.   You fire indiscriminately at your assailants, some of
whom deftly dodge the rays, while others are slain by them.    Then, of
course, you realize: these accursed beams are moving very slowly!   A beam
of light travels at more than 186,000 miles a second in a vacuum and at
nearly the same speed in air.  If the storm trooper can avoid the beam, it
is traveling thousands of times slower than lasers actually travel.     It
is true that a laser pulse can fry a nervous system and make short work of
storm troopers, even though they are completely enclosed in the most
expensive armor the Empire can buy.   However,  someone should tell the
Empire engineers to remove the anchors from the beams because the light is
moving like its 145 years old and doesn't really care any more.

WARP SPEED
Remember that scene when Han Solo was piloting the Millennium Falcon and
then floored it to light speed?  Well, how could one forget!    The
pinpoint stars rapidly elongated to luminous lines converging to the middle
distance.    If I might include a brief personal recollection.   I remember
my brother, Richard, took me to see the 1977 Star Wars movie and just
before Han et al accelerated to warp speed, he nudged me and said, "Watch
this!"    I did and was, of course, astonished and said, to the delight of
nearby viewers, "Wow, Dic, tell him to do that again!"    Now, had I known
then what I pretend to know now, I would have instead said, while
pedantically waggling an index finger, "Now, Richard, you realize that if
those oddly dressed people were actually traveling on board a vessel
traveling at light speed, they wouldn't be able to converse because time
stops at light speed.   The Theory of Special Relativity tells us that time
dilates on any moving object and that dilation relates directly to the
speed.  The faster the vessel, the greater the dilation.   If the
Millennium Falcon had achieved light speed, time would stop.   Of course,
the ship's mass also increases with increased speed, so its mass would
essentially become infinite at light speed, which would preclude it from
attaining that velocity."

And, we agree....the "Wow, Dic, tell him to do that again!"  was the far
less annoying thing to say.


RULING THE GALAXY
Alexander the Great would have liked this: he would never have run out of  to
conquer.   In the Star Wars Universe, the Empire ruled an entire galaxy
with a particularly hard iron fist.     Such domination would have
necessitated the development of a particularly advanced hyperspace travel
and communication infrastructure.     Let's imagine that someone wants to
govern the Milky Way Galaxy.   According to recent estimates, our one
galaxy contains more than 200 billion stars and, perhaps, an equal or even
greater number of planets.    Quite a lot of real estate to have under
one's dominion.  One would require untold trillions of minions to do one's
bidding and one would also need the means by which to convey the latest
dictates instantaneously to all your myriad underlings.     If you were
constrained by light speed, you wouldn't be able to maintain order.  Let's
just say a planet full of troublesome upstarts on the other side of the
galaxy starts to go all Libertarian on you and resists the Empire.    You
decide to send them a placating message of "Shut up and deal with it!" Even
if the message travels at light speed, it would require tens of thousands
of years to reach them, by which time the original agitators will have long
since perished. So, too, would you.

Of course, there is always the Von Neumann machine method.     An advanced
alien race constructs a vessel capable of traversing great distances and
self replication.  As it travels through the galaxy, it visits various
planets and mines raw materials from which it manufacturers components to
construct a copy of itself.  Once completed,  this copy proceeds to also
make copies of itself.  These, in turn, would be self replicating so that
after a comparatively brief time, perhaps 200 million years, Von Neumann
drones could be swarming through the galaxy.     Let's be cheerful and
further assume they've also been programmed to conquer inferior races
(i.e.  all of us) and, being incapable of empathy, have no compunction
about slaying the disobedient.    Perhaps through the agency of these
surrogates, a race could conceivably become both prevalent and
domineering.   Good luck collecting the taxes, though!


Then again, maybe the Star Wars franchise is just brilliant science fiction
designed to delight audiences, inflame imaginations, and enrich the movie
studios.  That is just fine by us because there is nothing more electric
and elating than escapist escapades into the remotest hollows of outer
space.




*The vast majority of life forms consist primarily of six elements: carbon,
hydrogen, nitrogen, oxygen, phosphorus and sulfur.   As we lack any
knowledge of extra terrestrial life forms, we cannot know if these elements
will be as predominant in alien beings.

**Yes, there are collective nouns specific to storm troopers and yes, I
actually took the time to look it up and yes, somebody else took the time
to make one up and then post it on line and yes, if you were a socially
awkward geek type you'd also have plenty of spare time at night to learn
collective noun words such as a doom of storm troopers, a shortage of
dwarves, a debauchery of hedonists, a metamorphosis of ovoids, a wiggle of
Elvis impersonators (you can't unsee that), a tabula rasa of empiricists
and, G-d help us, a handful of palm readers.
______________________________________________________

To subscribe or unsubscribe from the Daily Astronomer:
https://lists.maine.edu/cgi-bin/wa?SUBED1=DAILY-ASTRONOMER&A=1