Classical Astronomy - JUPITER AND VENUS CONVERGE

Published: Sun, 06/14/15



The day is thine, the night also is thine: thou hast prepared the
light and the sun.  Thou hast set all the borders of the earth:
thou hast made summer and winter. - Psalm 74:16-18


Hello  Friends,

In the last newsletter, I challenged the readers to take...


The 60 Second Challenge

I received seven emails out of over 3000 readers promising that they would go outside for just a minute to take a look at the sight of Jupiter and Venus converging toward each other.  Afterwards, I only got two replies, one very brief, and this one from Julie, a new reader:

We saw it last night; just as you said we would!  I even had two neighbors that were out talking, and I was able to ask them if they knew what they were looking at- the moon near Venus and Jupiter just beyond!  Thanks again for your work and your newsletter!

I'm happy to hear that, thanks Julie!  I hope that others are looking too, but just not writing.  But I'm sitting here in my chair, wondering whether or not anyone actually is looking. 


Friends, I give up a lot of weekends to create this FREE email newsletter, creating and images and describing the things that you can see in the evening sky.  All I ask in return is that you take a minute out of your busy life some evening to go outside and actually take a look for yourself!  But it's as simple as this: if you don't take a look, you're missing out on seeing God's wonders!  This June alignment of Jupiter and Venus has not occurred for 24 years, since 1991.  And this is the LAST time in anyone's lifetime that you will have this chance, since there will be no such alignment 24 years from now, in 2039.   

So I ask you again, take the challenge!  Go outside each clear night for just 6o seconds over the next two weeks and look at Jupiter and Venus!  The best part of this alignment is coming up, the actual close conjunction of Jupiter and Venus!  You don't want to miss this!  So program your phone, write it on your calendar, or hang sticky notes reminding yourself to spend a minute outside on clear nights this month, during late twilight, after sunset.  Do it with your kids, since they will never see this again in their own lifetimes!  And if anyone would please drop me an email and let me know what you see, I would be most appreciative!



For more information about topics from Classical Astronomy
discussed in this newsletter,please check out
a homeschool astronomy curriculum
(but popular with adult readers too!)


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*****  

Jupiter and Venus FINALLY Converge!
 
As we've been reporting throughout 2015, the planets Venus and Jupiter have been drawing closer together in the evening sky ever since last winter, and over the course of the spring. 

Jupiter and Venus are the brightest objects in the sky after the Sun and Moon.  These blazing planets are much brighter than any "stars" in the sky.  These planets are visible nearly all the time, most every night of our lives.  For some reason, this simple fact is not taught in the schools or reported in the media.  Most people today are not aware that the planets are among the most conspicuous objects in the sky, and are easily visible, even from the glowing lights of the city.  Thus, the bright planets are mostly unknown in our generation, even though they have been seen by all generations down through history, since ancient times. 

But you have a chance now, in 2015, to make friends with Jupiter and Venus!  All you need is a pair of eyeballs!  No telescope needed!  All you have to do is go outside and look!  It's that simple!  Yes, those two blazing "stars" in the western sky REALLY ARE Jupiter and Venus!  No, they are NOT airplanes!  And no, they are not UFOs!  Really!  Google "jupiter venus conjunction 2015" for more info if you don't believe me!!!

This newsletter has been reporting this event since last winter, when Jupiter and Venus were on opposite sides of the sky.  Throughout the winter and spring, these planets have been drawing closer together.  By the first week of June, these planets began to occupy the same part of the sky, and were both visible together at a glance, separated by only 20 degrees. 

Throughout the month of June, Venus and Jupiter have been drawing closer with each passing night.  But the closer these two planets get, the more change you will observe with each passing night!  By the evening of Monday, June 15, Jupiter and Venus will be separated by only 10 degrees!  If you hold out your fist at arm's length, Jupiter and Venus will barely fit in between that span!  But this gap between the planets will narrow noticeably every night throughout the second half of June! 
By the night of Tuesday, June 30, Jupiter and Venus will be right on top of each other!  At the precise moment of conjunction, best visible from Australia and the Pacific Ocean, Jupiter and Venus will be separated by a mere 0.4 degrees.  This is LESS than a single diameter of the Moon!  To put this into perspective, if you hold a regular #2 pencil at arm's length, the separation between Jupiter and Venus will be less than the width of the eraser!  
This is an extremely close conjunction, made even more impressive by the fact that it is a close conjunction of the two brightest planets.  Total eclipses of the Sun and Moon would be considered more outright amazing, but short of that, this close planetary conjunction is about as good as it gets.  So really, you should take a look each night at Jupiter and Venus, and decide whether you find astronomy to be a sufficiently interesting, worthwhile subject.

To understand what's going on in the sky, look closely at the above three pictures.  Notice that Jupiter stays mostly in a fixed position compared to the bright star Regulus, nearby in the constellation Leo.  Notice that Jupiter and Leo together drop a little lower toward the sunset horizon with each passing night.  These images were created specifically to depict that. 

Also notice that, in early June, Venus was lined up with the bright stars Castor & Pollux in the constellation Gemini.  But notice how Venus moves away from these two stars as it draws closer to Jupiter, and how the stars of Gemini appear to drop lower toward the horizon over the span of the month.  This is exactly the way the stars appear to move over the passing seasons.  This is how we observe the apparent movement of the Sun through the constellations.  This is the reason why the seasons change, and why the days grow longer and shorter throughout the year.

Everything would be easier to understand if we could see through the blue sky at noon.  We would then see the Sun's place among the constellations, and the entire solar system laid out before us, otherwise hidden by the blue daytime glare.  On the summer solstice, the first day of summer -- Sunday, June 21 -- we would see the Sun at the "feet" of Gemini.  This is the Sun's most northerly position of the year, and for this reason, the days are longest (but that's another story!)  We would also see Leo off to the east, with Jupiter and Venus in between Leo and Gemini, and the crescent Moon passing nearby. 
Many people ask why the famous constellation Orion can't be found in the sky this time of year.  It's because this constellation is near Gemini, and invisibly lined up with the Sun during the current month, hidden behind the blue daytime glow.  We'll see Orion again in the mornings of August and September, when the Sun moves away from Gemini, and Orion emerges from the sunrise.

(The seasonal variations in the Sun's position, and also the annual cycle of Orion and the other constellations, are explained in detail in our Signs & Seasons astronomy curriculum.  Check that out for more information.)



What's Going On Up Above? 

Suppose we could could see the solar system from a "God's eye view," looking down on the planets from above.  As the Earth circles the Sun in its orbit, the line of sight between the Sun and the background constellations is constantly changing.  At all times, the Sun appears to moving toward the east through the constellations (below).  In this way, the actual motion of the Earth appears as an apparent motion of the Sun.  But we can't directly perceive the Sun's motion.  Rather, it appears that the sunset is a fixed point on the western horizon each night, and instead, it appears that the constellations are steadily advancing toward the sunset and disappearing into the twilight glow. 

This is what we see in the pictures above, as Gemini is shown creeping toward the sunset horizon over the course of June, with Leo steadily advancing in that general direction.  In its turn, Leo will disappear into the dusk twilight over the course of the summer. 
Jupiter is a slow-moving planet, and appears to be relatively motionless compared to the constellation Leo.  So as the Sun "swallows" the constellations over the span of the months, Jupiter stays with Leo as it heads toward the place of the sunset, where it will also be "swallowed" into the twilight.  As seen from the "God's eye view," Jupiter will appear to pass behind the Sun, as seen from the Earth, and will then be on the far side of the solar system compared to our world.  Jupiter will be lined up directly behind the Sun at its superior conjunction, on August 26, 2015.  But until that time, we can still expect to see Jupiter in the evening sky, creeping each night closer to the sunset.  

Meanwhile, Venus is inside the orbit of the Earth, and always appears close to the Sun.  Thus, the motion of Venus always tracks with the apparent motion of the Sun.  So while Jupiter appears fixed in Leo, Venus keeps pace with the Sun's movement, actually scurrying a little faster than the Sun through the constellations. 

Venus emerged from behind the Sun this past winter, and was seen rising higher and higher in the dusk twilight after sunset. So Venus has literally been moving in the general direction of Jupiter, while this planet has been creeping steadily toward the sunset.  As the month of June progresses, Venus and Jupiter will be moving into alignment, where they will generally occupy the same line of sight by the end of the month (below).

However, Jupiter and Venus will actually be nowhere near each other!  Jupiter will be hundreds of millions of miles away, on the far side of the Sun, while Venus will be "only" a few tens of millions of miles away.  Venus is so much closer to the Earth, and appears brighter than Jupiter, even though Jupiter actually has a volume a thousand times larger than Venus. 

This month, on June 6, Venus reached its maximum elongation, when it was at its greatest distance from the sunset, 45 degrees.  Venus will appear to hang at about this same distance from the Sun for a couple weeks, into July.  In the meantime, Jupiter will "catch up" to Venus, so that these two bodies will move into close alignment. 
 
After its conjunction with Jupiter on June 30, 2015, Venus will begin to drop down toward the Sun once again, as it circles around between the Earth and the Sun on August 15, 2015.  But here's the REALLY COOL part... Venus will drop down toward the sunset at just about the same rate as Jupiter!  These two bodies will appear together in the evening sky for the entire month of July!  And though they'll be generally aligned the whole time, there will be a second "official" conjunction on July 31, 2015!  We'll explain more about that in next month's newsletter, hopefully in early July.  Meantime, keep your eyes on Jupiter and Venus every clear evening!  

(The orbital motions of the planets are explained in detail in our
Signs & Seasons astronomy curriculum.  Check that out for more information.)
     

Lunar Conjunctions This Month

Pay special attention to the Moon this coming week, as the New Moon emerges from the glow of the sunset, to signal the star of the Hebrew month of Tammuz.  The waxing crescent Moon will enter the scene on Friday, June 19, when it will appear below Venus and Jupiter after sunset.  By the next evening, Saturday, June 20, the Moon will be alongside Jupiter and Venus, making its closest pass to these planets.  The next night, Sunday, June 21, the Moon is near the star Regulus in Leo as summer begins for the northern hemisphere (as shown in the "solstice" graphic above).  Each of these nights are sure to offer a beautiful sight, so please do your best to see this with your family!
Again folks, please make it a point to observe these glorious sights that the LORD has placed over our heads.  And help your family and friends to see these sights too!  Forward this email to them, and share it with the members of your homeschool support group.  A summer alignment of Jupiter and Venus will not happen again in our lifetime, so don't miss it!

Til next time, God bless and clear skies,
- jay

The Ryan Family
Cleveland, Ohio, USA  

When I consider thy heavens, the work of thy fingers, the moon and
the stars, which thou hast ordained, what is man that thou art
mindful of him? and the son of man, that thou visitest him?
- Psalm 8:3-4, a Psalm of David