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From:
Edward Gleason <[log in to unmask]>
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Edward Gleason <[log in to unmask]>
Date:
Wed, 22 Jul 2020 10:52:17 -0400
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*Philomen and Baucis: *  *Hospitable hosts*
Just as the stranger was about to knock for the fifth and final time, the door
opened slowly.  Through the slit the stranger could see a single eye
regarding him sternly.  Behind the eye was a sliver of a warm,
well-furnished interior.
     "What do you want?" a gruff voice demanded.  The eye moved from the
stranger who had knocked to his larger companion standing just off to the
 left.
     "Please," the smaller stranger replied, "we are visitors to this
town.  We have neither a friend nor food.   May we humbly ask for some food
and a place to rest?"
     The door opened slightly more, enough to reveal an entire face.  At
first austere, the homeowner's countenance suddenly brightened with
amusement.  "Yeah, you may ASK!"
     He slammed the door.  The strangers heard the bolt engaged and the
listened to the  man inside make a disparaging comment to his family, all
of whom laughed gleefully at his biting remark.
     The two strangers looked upon each other sadly as they walked off
the porch.
  This reception -or lack thereof- merely confirmed what they had decided
twenty slammed doors before:  The quaint hamlet of Phyrgia was wicked and
inhospitable.  Throughout the day, both of them went from house to house:
two dirty, rag-adorned supplicants pleading for food and shelter.   Each
response seemed more hostile and cruel than the one which preceded it.
 They had been cursed, mocked, and once even swatted with a broom.    They
encountered angry grimaces for hours.     After this latest rebuff they
realized that they had visited each home except for the isolated little
cottage poised on the side of a large hill.      It didn't look like a
promising prospect: its dilapidated exterior showed its age.    However,
these two strangers were determined to try every home in Phrygia. As they
climbed the hillside, they could see crevices and bare spots on the cottage
walls:  it looked as though it were quite drafty.   Were it not for light
billows of smoke issuing from a back opening, they might have concluded
that the shack was abandoned.   As they reached the home, the men saw that
it was certainly old:  as though it could have been destroyed by a well
aimed wind gust.     Not exactly the home of people with much to offer
strangers.
      "I'll give your hand a rest," the larger stranger said to his
friend.  He knocked on the door and stood back a step, for he saw that this
door opened toward the outside, unlike all the other nicer homes in town.
 After a moment's silence, he knocked again.   He heard a rustling behind
the door and a muffled voice.   As he stood forward to knock again, the door
flew open.   The stranger was struck by the door and then by the clumsy old
fellow who had stumbled outside.
     "Hello?" the old man asked.  He recovered his balance before looking
up with fright at the large figure before him.  "Oh, my Heavens, look at
you!"
    The elderly fellow then clasped his hands and muttered nervously.
"M...m..may I help you?"
    The stranger told him that he and his friend were new in town, quite
tired and hungry.  "May we humbly ask for food and rest?"
    "Well," the man answered after a prolonged gulp. "of course.  Please
come in.  Both of you."
     The two strangers followed the twitching little man into his small,
but curiously neat domicile.  It was a single room with a bed in the corner,
a fire stove, cauldron and bench in the other corner.  Between both corners
was a door looking out onto a wide expanse of sloping green.   A small bare
shelf hung on one wall.  A rickety table and some chairs occupied the room's
center.  The home had little else besides. "You're most kind," the larger
man said as the two entered the home and closed the door.
     "Not at all," his host replied with an uneasy smile.  "I make it a
personal rule never to refuse the requests of seven foot tall strangers.
 Make yourselves comfortable." he said, gesturing to a bench located next
to their fire and  cauldron.   "Baucis!" he called to the open back door.
"We have visitors!"
        A rather elderly woman, who had been out back tending to the couple's
one goose, hobbled into the house.    She smiled warmly at the seated
guests.   "Welcome," she said, stepping forward with a handful of cabbage
leaves.   "Philemon, you old satyr, you didn't tell me you were expecting
visitors."
         "I wasn't, but, um, here they are.  They're hungry, tired and, um,
" he reduced his voice to a  completely audible whisper, "tall."   He
raised his hand well above his head for emphasis, in case his wife wasn't
sure what he meant.
         "Then, we should feed them well, indeed,"  Baucis told him.
 "Dinner will be ready in a few moments.  I'm afraid we can offer you only
cabbage soup and wine."
         The strangers both nodded "That is most gracious of you," the larger
one replied, smirking slightly.
         "How can I help?" Philemon asked, grabbing and then accidentally
dropping two wine cups from the shelf.   "Oh, dear," he said, stooping
slowly down to retrieve the cups.
         Suppressing her exasperation, Baucis told her husband to
stoke the fire
while she prepared the soup and wine, the latter of which was little more
than vinegar diluted with water.
         Philemon managed with great effort to build up the fire.   He
spent a few minutes  blowing on the embers and then a few more coughing on
the ashes, some of which fell in great clouds upon the smaller stranger.
 Horrified, Philemon muttered profuse apologies to his ashen-legged guest
as he frantically tried to wipe the ashes off the amused man's lap.   After
nursing the pain from a couple of violent knee swats, the smaller
stranger gently
but firmly grabbed Philemon's hands, assuring him that he needn't bother,
for he was not at all offended.
         The meal arrived a few minutes later. During the dinner the
strangers spoke rarely, preferring instead to listen with amusement to the old
couple speak of themselves.   They were poor farmers who had lived in that
house for more than fifty years.  They bought it for a pittance soon after
their wedding. They spoke of  their fondness -wholly unreciprocated-
of the neighbors
whom they had often invited to dine with them.  None ever accepted, hence
their joy at receiving these two men, whose names they had neither
requested nor received.  The old couple noticed that when the strangers did
converse, they spoke Latin and Aeolic Greek more eloquently than anybody
they had ever met.  The visitors switched between both languages
seamlessly, as though drawing the two tongues together into an elegant
tapestry of sound.   Baucis was particularly delighted by their
conversation, regretting that they didn't speak more.
           At one point, as the strangers spoke, Philemon watched his wife
finish her cup of wine.   Being enthralled by the visitors, she didn't
notice her husband as he went to fill some of her cup with his own.
(Something he did almost each night.)    The elegant sound tapestry was
torn by Philemon's uncharacteristically loud shout.  "Heavens!"
           The three others lurched back a bit, both startled and a bit
appalled by this sudden exclamation.
           "What is the matter!?"  Baucis demanded.
           Philemon merely pointed to the cup she had just drained.
           It was full again.
           Being aware of her husband's generous nature and knowing that he
refilled her wine cup every night, she merely replied, "Yes, I see it.
Thank you, my dear."
           "I didn't put any wine in your cup."
            Baucis looked at her cup, full to the rim.  Unlike the wine
that she had poured into the cup earlier, this wine was of the finest
vintage: its aroma, itself, seemed  intoxicating.   The elderly couple cast
grave expressions toward the visitors.  Even in the ancient world, most
people hardly ever encountered any supernatural phenomena.    This simple
old couple on a hillside certainly never had.   A cup that filled itself
with rich wine was a special sign.   A sign, they wrongly assumed, of
divine displeasure.
            They reacted as most people with no experience in mystical
realms would react.
            "We humbly beg your pardon!" Philemon pleaded, hoisting himself
up faster than one would think such an elderly man could manage. In haste,
he toppled over the soup bowl, splattering cabbage soup to the ground.
Even the generally imperturbable Baucis trembled as she rose from the
 table.  The strangers regarded them both curiously.
            Philemon aplogized profusely for the meal, confessing that it
was not the finest food they had to offer.  "We have been mean and meager
to our guests,"  he said to the sky.  "We implore the gods to forgive us
our stinginess. We have a goose we can prepare for their dining."
            "I'll fetch it!" Baucis said, moving swiftly toward the back
door.
            The next few minutes were a pandemonium of chaos.   The old
couple chased the terrified goose into the house.   Being much younger and
fearful , the goose ran for its life with the two desperate humans pursuing
it as quickly as their fragile bones would allow them.    They shouted at
it, grabbed at it, and once tried to corner on the bed, only to have it
flee between Philemon's legs with a flutter of dislodged white feathers.
The strangers looked at each other and laughed aloud.  This wild goose
chase was certainly one of the most amusing displays they had ever
witnessed.
            After the goose fled outside again, the couple stood breathless
by the bed.    The strangers arose to address them.
            "You needn't bother to feed us any more," the larger one
assured them.  "I am certain the gods are not displeased with you."
            "They're not?" Baucis asked, her wrinkled old man shaking by
her mouth.
            "No, we're not," the smaller stranger said with a chortle.
The rags the man had worn dissolved, revealing elegant clothing:  gold
emblazoned tapestries that the two had formed earlier with their voices: a
trick which only the Olympians could perform.
            "You have been hosts to the gods," the larger visitor
announced.  "I am  Zeus, your servant, and this is my companion, Hermes."
            After a moment of open mouthed silence, the old man, not
knowing the proper greeting for a visiting god, diverted his eyes and
spoke. "Ah....h...hello there..."
            Baucis kept her eyes locked on them and simply bowed with an
arm pressed against her chest.
            Zeus approached them  "Despite your poverty, you have been
generous.   Despite our strangeness, you have been hospitable.   I am
the guardian
of all lonely travelers and you have been most kind to us.  I am indeed
most pleased."   Both Zeus and Hermes bowed to them.  Zeus summoned them to
follow him outside their front door.  They saw, to their shock, a large
lake where the village had stood merely an hour before.   The light of
the setting
sun made it look like an ocean of amber.
            "What happened?"  Philemon asked breathlessly.
            Hermes waved his hand toward the submerged village.  "This day
was destined to bring a flood  covering the land.   We visited each home
and were turned away by the selfish and wicked.    Only one home received
us:   yours.   While the others were succumbing to the deluge, we were
dining.  The flood moved up this mountain, but we arrested its ascent.   Of
all Phrygia, only you two remain."
             The elderly couple looked down upon the water which covered
their neighbors: those folks who had universally regarded them with either
cold suspicion or open ridicule.
             Baucis sniffed silently to herself.  Philemon bowed his head
and wiped his eye.   A strong hand was laid upon his shoulder.  "Let's go
back inside."
             Once inside, Zeus offered them their greatest wish.    They
told him that they wanted to become his priests and to spend the rest of
their lives together.    Zeus granted this request at once.   Baucis and
Philemon were moved to a great palace, where, surprisingly, they lived for
many more years as attendants to the king of the gods.
             One day, far in the future, at the onset of a slightly chilled
evening similar to the one on which they had first encountered Zeus and
Hermes years before, they were standing together admiring the sunset.
Suddenly, they both felt their feet becoming rooted to the ground.  Bark
was growing rapidly up their bodies.   Knowing that their extraordinarily
long lives as humans were drawing to a close,  Philemon and Baucis reached
for each other just as their arms were transforming into branches.
Philemon smiled at his wife's face just before it became covered by bark.
He softly whispered, "You never thanked me for marrying you."  Philomen and
Baucis  became an oak and lime tree, which often grow together and share a
trunk.  It was a custom for people to drape wreaths over their branches as
a tribute to the elderly couple's kindness and generosity.

THE SOUTHWORTH PLANETARIUM
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Altitude:  10 feet below sea level
Founded January 1970
Julian Date: 2459053.16
2019-2020:  CLXXXII

THE DAILY ASTRONOMER
Wednesday, July 22, 2020
Remote Planetarium 69:   The Drake Equation

So, now we ask a question:   how many advanced races exist in the Milky Way
Galaxy?  We recognize that we are at something of a disadvantage when
addressing this issue because we know of only one life bearing planet and
we're living on it.    The importance of asking this question pertains to
the search for extraterrestrial life.   If life is exceedingly rare so that
a given spiral galaxy like the Milky Way might only harbor a few
life-bearing worlds, we shouldn't expect to detect any life at all, at
least not with the methods currently available to us.     However, if life
is so common that millions or even hundreds of millions of life- bearing
worlds are scattered throughout the galaxy, we should find a trace of at
least one of them before long.       Yet, how can we begin to take a census
of the Milky Way's advanced races?

We can't.
However, we can try to estimate the number through use of the "Drake
Equation," a mathematical marvel that combines science and speculation.
 It was formulated by radio astronomy pioneer Frank Drake (1930 -  ) who
has been searching for extraterrestrial signals for many decades.

[image: oodrake.jpg]

If you're feeling a bit uneasy, don't be.   The aim of today's lesson is to
work through the Drake Equation piece by piece.

*N      =  number of advanced civilizations in the Milky Way Galaxy*
This is the quantity we're trying to determine with all these values.   As
we shall see, N can vary widely from person to person, depending on their
assumptions about some of the factors within the equation.       We know
that the minimum value of N is 1 because of Earth.  Of course, some might
insist that based on human behavior the minimum could be zero.   Well, bah
humbug to that bunch.

*R   = rate of star formation in the galaxy*
According to recent estimates, about three solar masses of material are
converted into stars each year.   That material is not necessarily
transformed into three stars.    Remember that most stars are less massive
than the Sun.    This matter could be turned into as many as seven or eight
stars.      Or, perhaps, just one star more massive than the Sun.
Also, statistics is a tricky business.     Some years will experience more
star formation than others.    We remember also that star formation
requires millions of years.   By star formation, we refer to the point at
which the star becomes active by thermonuclear fusion reactions.

*fp = fraction of stars with planets*
Based on what astronomers have discovered so far, we can assume that many
stars have planets.      Analysis of the Kepler Space Telescope findings
shows that one in six stars has an Earth-sized planet in a tight orbit.
About twenty percent have a "Super Earth" in orbit around them.  (A Super
Earth is one that is more massive than Earth but considerably less massive
than gas giant planets.)

*ne  =  number of planets within a star's "ecoshell" or habitable zone*
Astronomers estimate that 40 billion worlds within the Milky Way Galaxy are
likely revolving within the habitable zones of their parent stars.   Eleven
billion of these might be orbiting Sun-like (G type) stars.    These
estimates are all based on the Kepler Space Telescope findings.   Data
collected from future missions might induce astronomers to modify these
estimates to some extent.

*fl  = fraction of those planets on which life develops*
Now we've careened headlong into the realm of speculation.
Unfortunately, the data point available in our own solar system.  As we
learned earlier this week, Venus, Earth and Mars are all within the Sun's
habitable zones.   However, Earth alone contains life.  That gives us a 1:2
ratio of life-bearing worlds to non-life bearing words in the solar
system.   Were that ratio to apply to other solar systems, we could assert
that life proliferates throughout the galaxy.    Our estimate becomes even
more optimistic if we find conclusive evidence that life actually did
develop on Mars early in its history.  That discovery would support the
notion that life arises quickly when conditions are conducive to its
inception.   Of course, it would also suggest that life can be readily
snuffed out, as well.

*fi  =  fraction of living species that develops intelligence*
Now we're truly limited.      Based on our solar system, the rate of
intelligent life developing on a life-bearing world is one hundred percent.
A beautiful 1/1 fraction.   Approximately 3.7 billion years ago, the first
traces of primordial life developed on the young, toxic Earth.  Now, we're
in the age of space stations and 5 G networks.   This fraction will remain
wholly unknown, unless, of course, some alien emissaries visit Earth and
present us with a comprehensive list of life-bearing worlds and intelligent
life-bearing worlds.    On the other hand, if we accept that microbial life
did arise on Mars before it was eradicated, then this fraction becomes
1/2.       Both fractions, however, are predicated only on our own solar
system and therefore might not be indicative of the galaxy in general.

*fc = fraction releasing detectable signals into space*
Well, we know we did, although we needed 3.7 billion years to develop the
capability.         During that immense amount of time, Earth sustained
asteroid bombardments and snowball Earth epochs, to name just two of the
perils life has confronted over the course of Earth's natural history.
  The greatest mass extinction, the Permian-triassic event, occurred 250
million years ago.    That mass extinction devastated 96 percent of all
ocean species and a majority of the other life forms, as well.     Earth
life literally required millions of years to recover from that extinction
event.       It is possible that life on other worlds was completely
destroyed by some great extinction.    We just know that life on Earth
survived.

*L  = length of time releasing detectable signals*
Two ways to approach this last value.    First, radio was invented in the
late 19th century.  By the 1940's humans developed atomic bomb technology.
 Not much later the nuclear stockpile we amassed was so large it could have
wiped out Earth life ten times over.    Humans were transmitting signals
for slightly more than half a century before they were at risk of
self-annihilation.          Secondly, many modern radio signals don't
propagate like the original waves did.      Many of today's broadcasts are
not broadcasting into space anymore.   Even if the outer space broadcasting
ended altogether today, humans have been transmitting detectable signals
for more than a century.       Again, Earth is our only data point and
might not be representative of other life-bearing planets, if they exist in
the first place.

The Drake Equation is not intended to settle the issue of how many advanced
civilizations exist in the galaxy. Instead, it provides us with a method by
which to estimate that number: one that will likely remain unknown for an
immensely long time.

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