712Rxjt4sPL._AC_SX522_.jpg
Paris:  Troy's downfall
A few nights before she gave birth to the infant Paris, Queen Hecuba, wife of the Trojan king Priam, awoke from a nightmare.  In her horrific dream, she was delivered of a flaming torch instead of a child.     Believing the nightmare to have been prophetic, Hecuba consulted the seer Aesacus.  After hearing the dream's details, Aecacus revealed that Hecuba's child would bring about Troy's downfall and should be dispatched immediately after birth.  Moreover, on the very day that the baby Paris was born, Aesacus announced that he had experienced a prophetic dream himself the night before in which Apollo declared that a child brought forth in the morning would end up destroying Troy and should be slain at once to preserve the kingdom.   Although King Priam believed Aesacus, he could not slay the infant.  He instead instructed his wife to do away with the child. Also unable to kill her child, Hecuba summoned their chief herdsman, Agelaus and pleaded with him to bring the child to his home and smother him.      Having looked on the baby, Agelaus was also moved to pity and could not abide by the queen's instructions.    Instead, he left the baby on Mount Ida, knowing full well that such exposure would end the infant's life.   However, a she-bear soon found the child and suckled it over many days.  Nine days after Agelaus removed the baby, Priam asked him to provide proof that he had killed the child as instructed.    When he returned to Mount Ida, the herdsman was astonished to discover the baby was very much alive in the very place where Agelaus had left him.       The herdsman decided to bring the infant home and raise him as though he were his own.    On arriving home, he killed a small dog and cut off its tongue.  He brought the tongue to Priam and assured him that it belonged to the slain infant.    The kindly Agelaus lovingly reared the child, named Paris.    Unsurprisingly, he grew to be uncommonly strong and handsome.      As a young man, Paris developed two passions:  the nymph Oenone and Agelaus' bulls.      Oneone became Paris' first lover and were, for a while, deliriously happy.     Paris was also happy to train Agelaus' fighting bulls, for he was unnaturally gifted at animal husbandry.  One of these bulls was by far the strongest and fiercest of them all.   It defeated all the other bulls in the battles that Paris had arranged them for to fight.     This bull proved so strong that Paris offered a crown of gold to any bull capable of defeating his bull.    Hearing of this challenge, Ares transformed himself into a bull and accepted the challenge.  Being a god in disguise, Ares won the battle.     Although suspecting the bull to have been of divine origin, Paris awarded the crown to Ares at once.  By this action, Paris demonstrated that his was an honorable nature.   Consequently, he was chosen to arbitrate one of the mythological Universe's most famous disputes.  Ironically, in so doing, Paris would show himself to be quite dishonorable, indeed.   The dispute involved the goddesses Hera, Athena and Aphrodite.  They all sought to possess a golden apple that Eris, goddess of discord, tossed into the crowd that had assembled to witness the wedding of Peleus and Thetis.  Eris was the only goddess not invited to the wedding.   The Olympians snubbed her because she tended to sow discord wherever she wandered, as was her wont.    She avenged this slight by throwing in a golden apple attached to the label "For the fairest."  She knew that all the goddesses were so insufferably vain that they would all vie for it.   And, indeed, the three most powerful goddesses all wanted it for themselves.   They went first to Zeus and asked him to decide which of them would receive it.   Realizing that by selecting one goddess, he would incur the implacable hatred of the other goddesses, Zeus declined to make the decision.    Instead, he instructed them to visit Paris, a Trojan shepherd, and have him choose.     Paris was naturally dumbfounded when he saw three goddesses materialize in front of him while he was tending the flocks.     Hera explained why they had appeared and what they wanted of him.   "You are to decide which of us shall have this," Aphrodite said, handing him the golden apple.  Paris looked at them all closely for quite some time.   Being young, brash and bold, he even had the audacity to ask them all to appear before him without apparel.   So adamant were each of them to win the contest, they consent to this impertinent request.    As Paris remained undecided even after this more intimate scrutiny, they all resorted to bribes.     Hera offered him to make him King of the lands we now call Europe.   Athena promised him profound wisdom and preternatural military skill.   Aphrodite offered him the world's most beautiful woman.       The viral Paris promptly gave Aphrodite the apple, much to the chagrin of the other two goddesses, of course.Thus ended the now notorious "Judgment of Paris."   Aphrodite assured him that she would fulfill her promise.   Unfortunately, complications arose because the most beautiful woman was Helen, wife of the Spartan King Menelaus.   Paris went to Oenone and declared that he was leaving her for another.    Having been trained in prophecy as well as the healing arts, the nymph knew in advance what was going to transpire.   'If you are ever injured, come to me to be healed," she offered.       Guided by Aphrodite, Paris then sailed to Sparta and approached Menelaus' palace.     Here, the sources diverge.   By one account, Helen spied Paris, fell in love with him at once and left with him willingly.  In another account, Paris entered the home and, seeing that Menelaus was nowhere to be found, abducted Helen.      In either case, Paris spirited Helen away back to Troy, much to Menelaus' displeasure.       He resolved to fetch her back, but first he had to summon all the men in Greece who had been Helen's suitors.      Prior to selecting Helen's husband, her father, King Tyndareus, made them all swear an oath to protect the sanctity of Helen's marriage, no matter who was chosen, so as to avert any violence that would have otherwise ensued following his selection.     So, after Helen was taken, all the former suitors were oath-bound to mobilize forces to launch an assault on Troy.    During the ten-year long siege that followed, Paris showed himself to be cowardly.   On two separate occasions, Menelaus challenged Paris to a duel so as to settle the matter between them, thereby ending the war.  During the first encounter, Paris fled from the enraged Menelaus.   During the second encounter, Paris does fight, for the other Trojans had chided him mercilessly for his cowardly retreat during the first encounter.   Menelaus rapidly disarmed Paris and would have slain him had Aphrodite not conveyed Paris back to the safety of his bedchamber.    Much later Paris was confronted by Diomedes, another powerful Greek warrior.   However, when Diomedes approached him while wielding a sword, Paris withdrew a bow and shot an arrow into Diomedes' foot.         Remarkably, much later in the Trojan War, Paris fired an arrow that killed Greece's most powerful warrior, Achilles.      Again, Paris shot the arrow toward his opponent's foot and it struck Achilles' heel, his only spot of vulnerability.     When Achilles was a baby, his mother, Thetis, dipped him in the River Styx to render the child invulnerable to all wounds.  However, she held onto Achilles' heel when he was submerged, thereby preventing the water from touching it, hence the phrase "Achilles' Heel," in reference to a person's greatest vulnerability.      Paris' arrow slew the mighty Achilles.   Toward the war's end Paris was struck by Philoctetes' arrow.   Helen brings him to Oenone and begs her to heal her first husband.  "You told him to see you if he were ever wounded," Helen reminded her.  "Yes," Oenone said sneeringly, "so he wouldn't seek the help of any other healer while he was wounded and could still be saved.   He spent his last precious moments traveling to see me, the one he abandoned for you.   A terrible waste of time, would you not agree?"    Horrified, Helen grabbed Paris so as to find another healer, but found that Paris had already died.      We know that the Greeks prevailed and Helen was restored to Menelaus.        In one version of this most famous tale, right after Paris kidnapped Helen, Athena, still embittered at having lost the apple to Aphrodite, replaced Helen with a cloud that assumed her shape and exhibited the same behaviors.   She delivered Helen to Egypt, where she remained in hiding during the war.      So, how ironic was it that a 10 year war was waged and an entire civilization was destroyed all because of a kidnapped cloud?

THE 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: 2459065.16
2019-2020:  CLXXXVIII

THE  DAILY ASTRONOMER
Monday, August 3, 2020
Remote Planetarium 75:  Nebulae  Part I of II

The article pertaining to nebulae turned out to be so image laden that it is necessary to divide it in two.      It turns out that if an e-mail contains too much data, the system rejects it.    Ironically, today's lesson doesn't contain much text. Nor will tomorrow's.     They are more akin to photo galleries with captions.  All the same, I hope you'll find it helpful.   

Were one to conduct a whirlwind tour of the galaxy, one would notice not only a vast abundance of stars, but also a great assortment of nebulae:   gaseous "clouds" scattered throughout the Milky Way's spiral arms.     Before we proceed to the galactic scale, it would be helpful for us to explore these nebulae and learn how they differ.      


Reflection Nebulae:

300px-Reflection.nebula.arp.750pix.jpg
The remarkable celestial object pictured above, called the "Witch Head Nebula," (IC 2118), is an example of a reflection nebula.     Rigel, Orion's brightest star, is close to this collection of gas and dust.      Dust grains within the nebula reflect Rigel's light, making it appear bluish.    The blue color is partially caused by the way dust grains more effectively scatter blue light than red light.  

pleiades-nov-2018-Fred-Espenak-Arizona-e1542547236557.jpg
The Maia Nebula envelopes the Pleiades Star Cluster in Taurus the Bull.   The stars within the cluster cause the surrounding gas to glow, much like a fireflies illuminate a fog bank.  Astronomers once believed that the gas was a residue of the 120-million year old cluster's birth nebula.  Now they have realized that the Maia Nebula consists of a dark nebula through which the Pleiades is currently traveling.

Reflection nebulae are the easiest to comprehend.    The gases are literally reflecting the light of nearby stars.

Emission Nebulae:

Whereas a reflection nebula glows by the light of nearby stars, emission nebulae generate their own light through a process called fluorescence.   During this process, the gases within the nebula absorb high energy radiation and then re-emits it at longer wavelengths

Fluoresce_Jablonski.gif
In this simplified model, a material absorbs incoming, high energy radiation.  It then emits energy at a longer wavelength/lower frequency.      


M42-Orion-Nebula-2-5-2016.jpg

 The above image shows us the Great Nebula located in Orion's sword.   Embedded within this gaseous cocoon is a small star cluster called the Trapezium.    With an estimated age of 300,000 years, this relatively young cluster imparts copious UV rays into its surroundings.   The UV radiation is absorbed and visible light radiation is emitted.     The Great Orion Nebula is 1,300 light years away and spans about 26 light years.  Thousands of stars are forming within this vast stellar nursery.     

Tomorrow, we'll focus on the remaining nebula types: primarily the nebulae formed by the death of stars.

To subscribe or unsubscribe from the Daily Astronomer: