Saturday, April 22, 2017

S is for summer constellations: Scorpius and Sagittarius

We’re looking for heavenly bodies in our A-Z tour during the month of April.  S is for Summer, which has two delightful constellations: Scorpius and Sagittarius.  We’ve met these guys when we looked at Orion, as their stories ties to Orion, but today we can spend a little more time on each.
Scorpius is the easiest to spot as it looks like a scorpion with two pinchers and a curved tail ready to sting.  In the summer, from North America, it is seen on the southern horizon.  It is the southern-most constellation in the Zodiac.  If you are too far north, like northern Michigan, you won’t see the full tail.  But here in Georgia, when I’m out on the water in the evening or have a clear view to the south, the pesky insect is clearly seen.  It is also in a rather dark part of the Milky Way, which is appropriate as scorpions like to hang out in dark cracks.  As we learned at Orion, the scorpion bite the great hunter, mortally wounding him, which is why you never see Orion and the scorpion in the sky at the same time. 

Not far from Scorpius is Sagittarius, a centaur, half human and half horse.  This constellation is the Comanche of the sky.  The Comanche became feared warriors not only to soldiers and settlers in West Texas, but also to neighboring tribes as they mastered the art of war from the back of a horse.  In a way, they were at one with their horse, while soldiers and even other Native American tribes used horses as transportation but would generally dismount to fight.  As there is another constellation featuring a centaur, named Centaurus, it creates some confusion. There is even a debate about which centaur is Chorion, with some saying it is Sagittarius and others saying it is Centaurus.  Chorion was married to Rhea, who was so jealous that he changed himself into a horse/man as a way to escape her, showing that there is at least 51 ways to leave your lover. 
 Although many people envision a teapot from the key stars in Sagittarius, I see a bow drawn back and aiming at the red star Antares, the heart of Scorpius.  To the east of Scorpius, Sagittarius is chasing the scorpion from the sky.  Sometime this summer, find yourself with a dark and uncluttered southern horizon and see if you can make out these constellations.  Of course, if you live in the southern hemisphere, you will find these constellations high in the northern sky.

Have you ever seen these two constellations?  

Should I have included the Sun in the letter S or is it too obvious?

Friday, April 21, 2017

R is for.... get this.... Reticulum

R is a difficult one for the A-Z heavenly body challenge.  There is only one of the eighty-eight modern constellations that begins with an R, Reticulum.  To my ears, the name sounds like something a physician might utilize in a prostate exam.  Thankfully I don’t have to worry about having it staring me in the face when I am admiring the stars as the constellation cannot be seen at all from the continental United States.  You might get a glimpse of it in the southern Hawaiian Islands from October through December, but even then it’s going to be low on the southern horizon.  The constellation is not seen at all above latitude 23 degrees north. 

Like many of the southern hemisphere constellations, Reticulum is a relatively recent addition to the lists of constellations.  It was identified in the early 17th Century, but not added to the official list of constellations until 1922.  There are no stories or myths associated with these group of faint stars that supposedly represents a net.   However, it’s not a fishnet, but the gird lines within a telescope, the reticle.   And good luck with seeing this constellation, especially without a telescope.  There are only six of the stars with a magnitude bright enough to be seen by the eye without magnification, and none of them are very bright.

In 2022, the constellation will officially be 100 years old?  Shall we throw a party?  We could all dress up like urologists.  On second thought, I’m sure I have something else scheduled.  What about you?  Would you be interested in a party celebrating Reticulum’s centennial?  

Wednesday, April 19, 2017

Q is for Queen Cassiopeia

We’re at Q in our heavenly bodies A-Z challenge tour.  Since there are no constellations or planets that begin with a Q and since I don’t really understand things like quasars (which don’t really fall under the “heavenly bodies” category as I am interpreting them), I’m going to cheat just a bit.  At Andromeda someone suggested that they bet C would be Cassiopeia, but they were wrong because I had anticipated this problem and saved Cassiopeia for now.  Today’s heavenly body is “Queen Cassiopeia,” the wife of Cepheus (we explored him under the letter K for King Cepheus).  Cassiopeia is a heavenly body in the beauty since, for she thought she was the most beautiful woman ever which, as we saw when exploring Andromeda, got her and her husband and their kingdom in trouble.   

Cassiopeia is easy to spot.  She is the W or the M  (depending on which side of the Celestial Pole the constellation is at) that circles the pole and in the middle northern latitudes can be seen all year.   She is on the far side of pole from the Big Dipper.  Although a queen, the five bright stars making up the W are not a crown as one would think…

In addition to being a queen, other cultures have seen different things.  In the Middle East, the stars have been seen as a women’s hand and a camel.  Lapplanders understood it to be a moose antler.  In Siberia, the five bright stars were seen as five reindeer (and as it is over the pole, maybe they belong to Santa, but we’re missing a few).  In the Marshall Islands, the “W” of Cassiopeia was seen as the back fins of a huge porpoise (that extended out, borrowing stars from the constellations Perseus, Andromeda, Triangulum and Aries). 

Have you ever seen Cassiopeia?  Do you think of her as a W or a M? 

P is for Perseus

P is our letter in this year’s A-Z challenge tour through the heavens.   There are nine constellations that begin with a “P”:  Pavo, Pegasus, Perseus, Phoenix, Pictor, Pisces, Piscis Austrinus, Puppis, and Pyxis.  Of those, only three are well known: Pegasus, Perseus and Pisces. There is also Pleiades, the seven sisters, which while not listed as a constellation is certainly a well known formation in the sky. Knowing it was going to be hard to pick, I covered Perseus under “F” for “flying horse.”  We could explore Pisces, which is one of the Zodiac constellations, but instead I’m going to go to Perseus.  We’re already met Perseus, who saved and then married the lovely Andromeda after he’d beheaded the horrific Medusa.  But there’s a lot more to his story.
Perseus is the son of Jupiter (you know, the god who had a thing for beautiful mortal women).  His mother was the beautiful Danae, who lived in Argos that was ruled by her father, Acrisius.  His was a dysfunctional family if there ever was one.  He was afraid that his daughter was going to kill his son, so he locked her up in a tower, not allowing her to marry.  But Jupiter, being a god, wasn’t deterred by a tower.  From their union came Perseus.  Acrisius then cast his daughter and grandson out to sea in a chest.  With the gods watching over them, they ended up on the island of Seriphos. 

While Perseus was away, the wife of Polydectes, the island’s chief, died.  He set his eyes on Danae, but she didn’t love him.  In retaliation, he made her his slave.  Of course, this didn’t please her son, Perseus, who was ready to kill Polydectes.  But instead of killing him, he acted on a dream and the aide of gods and went off to kill Medusa, one of the Gorgon sisters.  Mercury had loaned him his flying shoes and Minerva loaned him a sword and a bright shield that she suggested he use to look at Medusa, for to look at her head would mean certain death.   On the way to find the Gorgons, Perseus stopped by Atlas who was tired of holding up the earth.  Atlas gave Perseus a special helmet that allowed him to be invisible, asking Perseus to stop by and show him Medusa’s head when he was done.  Perseus cut off the head of Medusa, stopped by and showed it to Atlas (who turned to stone and became a mountain in Africa).  As he was making his way home, he saved Andromeda.  When he finally got back home, seven years later, there was a banquet where he displayed Medusa, turning the chieftain and his guests into stone.   

Perseus is best seen in the autumn sky as he leads his wife, Andromeda, up into the sky.  He is just above the Pleiades (the seven sisters).   The constellation has a number of interesting stars including Algol, a binary star that significantly changes in magnitude every 69 hours (as one star crosses in front of the other).  In the ancient world, this star which would be in Medusa’s head was seen as the winking eye of the beast. 

Late at night in mid-August is the Perseids meteors (which I wrote about under the letter M for “meteor”).  

Tuesday, April 18, 2017

The Letter O: Orion (and a bit about Ophiuchus)

Today in my A-Z challenge, we’re looking at things in sky that beings with the letter “O”.  There are three constellations u fitting this bill: Octans, Ophiuchus, and Orion.  Unless you live pretty far south of the equator, you’ve probably never heard of Octans, as it is around the Celestial South Pole.  It’s a more recent constellation, named for the tool used to determine latitude before sextants came into use.   It also doesn’t have a bright start like Polaris.  Ophiuchus, the snake handler, is found along the zodiac and is better known, but Orion is perhaps the best known constellation in the sky.   Of course, you probably didn’t know that Ophiuchus is in the Zodiac, but it is between Sagittarius and Scorpius.  It was in the Zodiacs of the Greeks and Romans and the modern scientific community, but not the one of fortune-tellers who have only 12 signs.   Although a neat constellation, it pales when compared to Orion, the most beautiful constellation in the winter sky.  
I have spoken of Orion several times in this tour, as we’ve looked at Betelgeuse   and this at Canis Major, his famous dog in the sky.  Orion is a huge constellation and from it you can find many other constellations in the winter sky.   I expect this constellation may be the most popular one in the sky, surpassing even the Big Dipper, because its position around the equator allows it to be seen by so much of the earth.

Orion drew my interest into astronomy.   As a child, I spent many nights fishing on beach during the fall.  In October, you’d see Orion rise, on his side, around 9 PM.  Later in the fall, it was early and by Christmas he’d cleared the horizon well before dark.  You can still see Orion now, shortly after dark, dropping in the Western horizon.  The most distinguishable feature of Orion are the three stars of his belt.  It’s easy to see the knife hanging off the belt, his arms and legs.  There are many bright stars in the constellation including Betelgeuse (12th brightest star in sky) and Rigel (his left foot and the 8th brightest star).

Almost every culture has a story about Orion, along with a different name.  The most common myth is that Orion was the son of Neptune and Euryale (a nymph).  He was a huge and fearless hunter who boasted that he was exterminate the animals of the earth.  Hearing this, Gaia, the goddess of earth, sent a scorpion that bit Orion, causing a mortal wound.  But he was saved by Ophiuchus, the snake handler who was also a physician.  This is all played out in the sky, as Orion is never present when the scorpion (Scorpius) is in the sky.  Furthermore, as Scorpius sets, Ophiuchus stands over the insect, trampling him.   In another story, Sagittarius, the archer, was sent to avenge Orion’s death and the archer’s arrow is pointed at the scorpion.  

Although he is not in the sky, Samuel Clemen's (Mark Twain's) brother was also named Orion.  Supposedly, their mother was interested in the stars and thereby decided to name her older son for the constellation.  The constellation Orion also appears three times in the Bible (Job 9:9 and 38:31   and Amos 5:8).