A Curious Celestial Configuration - By Contributing Astronomy Editor, Dan Matlaga

Welcoming Back Professor Dan 

With some timely information regarding the night sky TOMORROW NIGHT!  

Read on:

If at 10:30 p.m.your southeastern sky is clear the night of Saturday, May 21^st you can see a curious meeting of four objects forming a square close to the horizon.  Figure 01 illustrates the view. 

ENLARGED THE PICTURE AS MUCH AS POSSIBLE, STILL A LITTLE TRICKY TO SEE THE NAMES.
THEY ARE (LEFT TO RIGHT, TOP 2): THE MOON AND MARS AND (LEFT TO RIGHT, BOTTOM 2):  SATURN & ANTARES

The four objects are the Moon, Mars, Saturn and the bright star Antares. The field of view in Fig. 01 is sufficiently large to include the South and East cardinal point designations, this to signify the scale of the quadrangle.

The moon is the brightest object of the four; the brightest because it is near. The moon reflects only 7% of the sunlight that strikes its surface.  It is really a poor reflector.  The Earth reflects 30%, Mars 29%, and Saturn 47%. The Moon, a quarter the size of the Earth, is but a quarter million miles from the Earth.  That is, a beam of sunlight reflected off the moon’s surface will take but 1.3 seconds to reach your eye.

One month out of 24, Mars, half the size of the Earth, is opposite the sun in our sky and is said to be “in opposition.”  In the present cycle, Mars will be in exact opposition May 22nd, just one day after this night’s observation. As you view Mars, the light that strikes your eye left Mars 4.25 minutes ago.

Saturn is the sixth planet from the Sun.  Nine and a half earths would have to be lined up to equal the diameter of Saturn. The light from the planet Saturn takes 1.25 hours to reach the Earth.  

Note where Saturn is on May 21^st.  Come back 29.6 years later. During that time Saturn would have appeared in front of each 12 zodiacal constellations. In 29.6 years it will be back in the same position you see it on May 21^st. Where will you be 30 years from now?

Mars looks like a red star, Antares is a red star. It is one of the largest stars visible to the naked eye. If Antares were the size of a baseball, our nearly one million mile diameter Sun would be scaled to smaller than the period at the end of this sentence.  Antares “surface” temperature is about 5,700 degrees.  The Sun’s surface temperature is 10,000 degrees.  How can Antares be so bright at a distance of 600 light years and so cool? Place Antares where the Sun is and the planets Mercury, Venus, Earth and Mars would orbit inside the star.  There are many square miles of surface area on Antares pumping out the red light. Antares is in fact 11,000 times brighter than the sun.

The word “Antares,” comes from the Greek.  It translates as: “the enemy of Mars.” Ares was the Greek word for Mars, while the prefix “An” can loosely be translated as “Anti.”  The idea was every two years Mars and Antares ride the sky together. The tension was… “which of the two will be the brighter red?”  You can judge for yourself who wins this time.  Or, to be honest, you can wait a few nights when the bright Moon’s light is no longer part of the picture. 

Thanks Dan!  I, for one, will be sure to check all of this out tomorrow night and I'm sure all of our Kabrini Message astronomy buffs (and there are many!) will, too.

Venus is Bright - By Contributing Astronomy Editor, Dan Matlaga

Aphrodite - Venus, Goddess of Love

How bright is Venus?

Venus is so bright...

...If you are observing from a dark sky site,Venus will cast shadows.

...Venus is the third brightest regular object in the sky.  The Sun and The Moon are the only two regular objects that can outshine Venus.

...Venus can be seen in broad daylight.

It is easy to see the planet Venus during the daylight hours because Venus is now brighter than the blue sky.

Four panels illustrate how simple it is to find Venus while the Sun is in the sky.

Go outside at 8:15 or so and face the West.  The two bright star looking objects are the planets Venus and Jupiter,  Venus is the one on the left, brighter and slightly higher than Jupiter.  Walk around so you can place Venus next to some landmark on your Western horizon.  Mark the spot  you are standing with a brick, stone chalk mark or whatever.

Next night stand on the same marker, look to the West but do this at 8:00 or fifteen minutes earlier than the first viewing.  You will find Venus will be above where you saw it a day earlier.

Walk around so Venus is once again lined up with a marker on your local horizon... a tree branch,  telephone pole,  neighbors house, or something. Mark where you are standing.

The third night repeat the same steps but now at 7:45.

The forth evening the sun should be above the horizon at 7:30.  If at first you can't see Venus keep looking.  Within 15 minutes it should appear where you saw it on the third evening attempt.

If you keep repeating these observations you may be able to continue until Venus will be visible to you at 5 or 4:00 late afternoon.  

The times given are for Tempe Arizona.  We do not have daylight saving time. We have too much sunlight for such childish things.  

Note:  Your first observing evening should correspond to a time when Venus is visible with a few background stars in your sky.

Editor's Note:  And lastly...Just for fun...here's what Frankie Avalon had to say about Venus back in 1959!                                                                                                                                  

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Venus, Mars and the Moon - February 20, 2015 - PART 3 - by Contributing Astronomy Editor, Dan Matlaga

              

FIGURE 1

If you were watching the western early evening skies this past week you would have seen the decreasing separation between the planets Venus and Mars (Figure 1). Minimum separation occurs Friday evening with the addition of the thin crescent moon.

FIGURE 2

The view of the western early evening sky of February 20 is illustrated in Figure 2.  Venus outshines both the moon and Mars.  Although the moon is represented in Figure 2, it does not register at the resolution of the figure, though the moon will be easily visible to the casual observer facing west.

FIGURE 3

A pair of binoculars might enhance the naked eye view.  Figure 3 is the view through a pair of 7X35 binoculars.  This is a popular size of binocular.  The first number "7" designates the magnification of the binocular. The size of the large lenses furthest from your eye while using the binocular provides the diameter of the lenses in millimeters, in this case "35" millimeters or roughly 1.5 inches.

 Note the image of the moon.  It consists of a bright crescent.  That bright crescent is the part of the moon illuminated directly by the sun, light from the sun reflected off the moon to earth.  The rest of the moon has an ashen look.  The ashen light is the result of light from the sun striking the earth, reflecting off the earth to the moon, then reflecting off the moon to the earth and into your eyes.  Not bad for the moon which reflects on average only 12% of sunlight, and is therefore a very dark object. This view of the moon has been described as: "The old moon wi' the new moon in her arms."

The scene before your eyes the evening of the 20th is somewhat of an illusion. Venus, Mars and the Moon are not that close in space.  We can illustrate this using the speed of light. A beam of light can travel 8 times around the earth in one second, yet that same beam of light takes about 8.3 minutes to travel from the sun to the earth. We say then the sun is 8.3 light minutes away from the earth. On the 20th of February the sunlight reflected off the moon takes but 1.2 seconds to reach the earth, Venus nearly 12 minutes and the reflected sunlight from Mars takes 18 minutes.

This is the third of four submissions concerning the planet Venus in the western evening sky. As you observe the Moon, Venus and Mars this evening, you might take a second to look directly east.  The brilliant star like object hovering directly above east is the planet Jupiter.  

The very close appearance of Venus and Jupiter above the western horizon the evening of June 30th will be the 4th of 4 postings.  

The separation between Jupiter and Venus is decreasing already. Look tonight to the west at Venus, then to the east at Jupiter... the June 30th event has begun! 

"Close Approach " of Venus and Mercury PART 2, by Contributing Astronomy Editor, Dan Matlaga

                                    January 20-22, 2015

 

FIGURE 01

Let's examine Figure 01, depicting the southwest backyard sky at about 6:15 p.m. on January 20, 2015. This is a time when a half-dozen stars are visible in your evening sky. Features include the positions of the Moon, Mercury, Venus and Mars.

A line drawn from the "S" which stands for South and to the "W" which stands for West would be the horizon if you were standing on a boat in the middle of the ocean. 

The Moon in our setting is just above the South-West horizon.  It is an eleven hour moon.  At 7 a.m. this morning the moon and sun were on the same north south line. The moon travels around the earth such it moves its own diameter each hour, or as viewed in the sky, half-degree each hour. At the time of our diagram, the moon has separated from the sun by 5.5 degrees.

Technically above the horizon, practically it would be very difficult to observe the 11-hour moon this close to the horizon, even though you were trying to observe it atop a large sand dune in the middle of the Sahara.  Only 0.4 percent of the moon is illuminated.  Figure 02 illustrates how little this is.

FIGURE 2

The illuminated crescent part of the moon does not present a continued light line, but is broken up in places due to the moon's crater walls seen edge on.

The brightest image in our sky is the planet Venus. It is the anchor in this our second posting of four; since our last posting of January 10th, when Venus and Mercury were very close in the sky.  Now, just ten days later, Mercury has peeled off to the west and below Venus. 

Mars is above Venus.  It will be interesting to watch from one evening to the next as their separation decreases.

                                    January 21, 2015

Just 24 hours later, we note from comparisons of last evening sky to this, the increasing separation between Venus and Mercury. (Fig. 03)

FIGURE 3

Last evening the Moon was 11 hours old. This evening it is 11 hours old plus 24, or 35 hours old.  It has increased from 0.4 percent illumination last evening to 1.3 percent this evening. (Fig.04)

FIGURE 4

This evening marks the first evening when the crescent moon is an easy target for the backyard observer.  Finding the moon's position is aided by its close proximity to the planet Venus. Two nights and three days ago the moon was an equally visible object in the morning sky immediately before sunrise.  Two nights and three days equal 72 hours. It took the moon 72 hours to pass from the morning sky to the evening sky. Half of 72 is 36.  We have a 35 hour moon this evening in good agreement of a standard two nights and three days traditional description of the dark of the moon, when the moon is not visible to the unaided eye.  

The Greek goddess of the Moon was Artemis. As the goddess of transitions she was a goddess of birth and death.  The crescent moon mythically died two nights and three days ago but now reborn as a crescent in this evening sky. A Greek word to describe a thin crescent moon is the word "Cynthia," abbreviated as "Cindy." Parents in search of a name for their newborn find Cynthia listed as another name for the Moon goddess Artemis.  This is a translation I would expect from a high school guidance counselor or worse yet, from a gym coach. An appropriate sense of the name Cynthia is: "She who hunts among the clouds."

The separation of Venus and Mars continues to decline.

                               January 22, 2015

This is the evening sky at about 6:20. (Fig. 05)

FIGURE 5

Note the position of Mercury. It is getting very low and by month's end will rise and set at the same time as the sun.

In just 24 hours the moon has changed its position from the west of Venus to the west of Mars. If we could pace the apparent distance the moon traveled from last evening to this evening, multiply it by 29.5 times, we would have marked a great circle around the sky. We would find the moon back to the same phase as tonight. This number is near the 30 day cycle of the month.  The month does indeed get its length from this, the Synodic cycle of the moon.

The moon is 9 percent sunlit. (Fig. 06)

FIGURE 6

I refer to this phase of the moon as the Romantic Moon, because it will take the moon 2.5 hours to set; more than enough time to accomplish the tasks at hand.

"Close Approach " of Venus and Mercury by Contributing Astronomy Editor, Dan Matlaga

The illustration shows the "close approach" of  the Planets Venus and Mercury at 6p.m. January 10th and 11th.  The apparent close planetary images is an illusion.  The planet Venus, on the far side of the Solar System is emerging from behind the Sun while Mercury is on the same side of the solar system as the Earth and will pass between the Sun and Earth on the 29th of January.

 It is the pairing of the fainter Mercury with the brighter Venus that makes the planet Mercury an easier target for backyard observing. This is the first of Venus paring with four celestial objects worth noting.  It was these apparent motions of the Sun, Moon and five visible planets that had a profound effect on human culture. 

Watch this space!

Orion - Part 2 - By Contributing Astronomy Editor, Dan Matlaga

We pick up at the point where we left off in the Orion Part I Post of March 6th

The Great Goddess and the Constellation Orion

With the absence of the evening moon, we can address an interesting aspect of these evening skies.

If you can locate but one constellation in the sky, chances are you can find the constellation Orion.  Orion's signature of three bright stars marking the giant's belt is unmistakable.  It is important to remember Orion is found by three bright stars.  It comes into play in another submission to the topic of Orion and the Great Goddess.

Orion has just about every award a constellation could hope for.  It has more bright stars than any other constellation, looks most like the object it is supposed to be and its position in the sky guarantees it is visible from every inhabited part of the earth.

In addition, consider the constellated scene composed of Orion the Hunter, Taurus the bull, and Canes Major, the large hunting dog of Orion.  Is there a more dramatic stage of constellations?

There is Orion with his unbreakable bronze club poised high over his head.  A shield of lion skin is all that separates him from Taurus.  The charging bull with head lowered and horns locked into position is but a second or two from putting an end to our giant hunter.  Can you imagine the ensuing battle of cosmic proportions?!  What fertile ground wheeling nightly over our heads for Greek storytellers, playwrights, and authors of epic poetry!

Actually you will have to use your imagination.  There are no stories, songs or poetry to come down to us from classic Greece that describes Orion in a bull fight.  It is certainly possible these items were simply lost to us.  "Lost to antiquity," was a popular phrase used in texts a century ago; though we do have another who brandishes a club and lion skin.  The constellation Hercules is a late Spring constellation made of dim stars.  We do have stories of how Hercules obtained his club, how the first of his twelve labors was to slay the Nemean lion whose skin according to some, he wears and is just short of covering Hercules's derriere.

Surely we can speak of legends of Orion and his trusty dog Canis Major.  Of the hunt Orion and Artemis shared, Canis Major must have been instrumental in the basic feature of tracking and cornering wild animals as part of his hunting dog duties.  In my half-century of reading Greek and Roman mythology all that I have been able to come up with regards Orion and his dog:  "Orion has a stick.  He throws it into the sky.  The dog grabs it and buries it.  That is where the first grapevine grows in Greece."  Where is even the merest dimension a hunting dog this animal is supposed to supply?  Lassie was more active every Sunday evening.

Here are the three boasts of Orion:

1. He is so tall he can wade across the Aegean Sea.

2. He is such a great hunter he can kill every living thing on Earth.

3. He is so strong he can tear out an Ash tree with his bare hands and carry it down  the mountain.

Quite an impressive list for our giant hunter.  Unless you begin to address the constellation at the giant hunter's feet.  It is Lepus, the rabbit or hare.  Why would a giant of this magnitude be content with the timid rabbit at his feet?  Planetarium lecturers, authors of constellation books and others who have a difficult time understanding metaphor have no trouble with this pair. "Of course there is a rabbit at the feet of the hunter... the hunter must have something to hunt and so there is the rabbit."  We have no Greek plays, songs, or epic poetry where Orion fights a rabbit.

The mythology we do have of Orion appears to be bits and pieces of other stories that have been spliced together to form what we call the mythology of Orion.  They do not form a coherent story of the life of Orion. In their popular 630 page text used in university mythology classes Mark Morford and Robert Lenardon devote 19 lines to Orion.  Less than a half-page, with no mention of a bull, dog or rabbit.  It is as though the constellated Orion and the mythology of Orion have less in common than what we learned in grade school, planetaria and books about constellations.

Here is a list of constellations around Orion known to the classic Greeks.  Beginning from the north and moving clockwise we have:

• Auriga - the charioteer holding a mother goat and two or three kids
• Taurus - the bull
• Eridanus - a river
• Lepus - a rabbit or hare
• Canis Major - a large dog
• Canis Minor - a small dog
• Gemini - the twins Castor and Pollux

Let's change the list to nine items of a charioteer, a mother goat and three kids, a bull, a river, rabbit, large dog, small dog, twins.  With the items disassociated from the constellated world, ask anyone who understands Greek mythology:  "What do these nine items have in common?"

If they really do understand Greek mythology, it should take something in the order of a second or two to respond: "Simple... these are all symbols of the goddess Artemis."

It will take several more submissions to explain how Artemis is a better fit for the stars of Orion and surrounding Greek constellations.

Stay tuned...more to come soon.  Thanks Dan!