This is the
Classical Astronomy Update, an email newsletter especially
for Christian homeschool families (though everyone is welcome!) Please feel free to share this with any interested
friends.
For I am persuaded, that neither death, nor life, nor angels, nor principalities, nor powers, nor things present, nor things to come, Nor height, nor depth, nor any other creature, shall be able to separate us from the love of God, which is in Christ Jesus
our Lord. -- Romans 8:38-39 IN THIS UPDATE Jupiter and
Venus Approach Hello Friends, Thanks very much to all of you for reading this email newsletter! In this every changing internet landscape, email newsletters are mostly a thing of the past. Email is old news, for dinosaurs like me. Seems like nobody reads email anymore, people today instead stare at a talking head on a podcast. While it might be fun to do something like that, I'm still
basically a 20th century kind of guy, a product of the previous millennium. Email is fine but I would much rather curl up with a good book (paper book that is, anyone remember those? wood pulp? non-volatile storage media?) rather than spend even more hours staring at a screen. So anyway, for these reasons I appreciate all of you who have hung in there with this email newsletter. And I welcome all of you who have recently joined this list. As long-time subscribers know, I won't load up with your inbox with marketing pitches like all those other email newsletters from homeschool hustlers. It's just me and
my computer, your friendly neighborhood author/self-publisher/shipping clerk, doing what I have always done in creating this newsletter for 26 years, 21 of those years written especially for homeschoolers. The subscriber list
shrinks a little every time I send a newsletter. People unsubscribe or are automatically removed for a bounced email address, and only a few new subscribers sign up to take their place, since email is a fading medium. So if you like this work, please forward this newsletter to any friends who might be interested, whether or not they are homeschoolers. And if you are a homeschooler, please circulate this in your co-op or other circles. If you're on social media, you can
post a link to our our archive of previous editions. Thanks! It's always amazing how quick the time goes by. Seems like it took a fair chunk of time in life to reach 30, but the last 30 have disappeared so quickly, piling up behind in the rear view mirror. Scripture is so true and this verse is increasingly relevant: Whereas ye know not what shall be on the morrow. For what is your life? It is even a vapour, that appeareth for a little time, and then vanisheth away. – James 4:14 You read that verse when you're young and you think you understand the basic concept, but it's head-spinning to actually watch your own life vaporize like that. Anyway, the point is, you lose track of time when it flies by so rapidly. I've tried to write a fresh newsletter each time and not cover the same ground over and over. I've done many newsletters about planetary conjunctions over the years, and conjunctions of Jupiter and Venus are the most fun since they are both
such dazzlingly-bright objects, and their celestial alignments are conspicuous and beautiful. But I usually don't retread the mechanics of why this happens, since it seems like I've done that many times in the past. Well imagine my surprise when I saw that the last time I explained all that was in 2015, eight years ago! A lot of subscribers have come and gone in the meantime, so it was well past time to revisit the subject. 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!) Visit our archive of previous editions of the Classical Astronomy Update newsletters, going back to 2007. *****
Jupiter and Venus The bright planet Jupiter passed opposition back on September 26, when it was opposite the Sun (hence the name), rising above the horizon as the Sun vanishes at sunset.
Jupiter has been exclusively an evening sky object since that time. As with all the other superior planets, including Mars and Saturn, Jupiter has been inexorably creeping a little closer toward the sunset with each passing night, being left behind by the faster-moving Earth. Lately Jupiter has been to the west of the meridian at sunset. But in its own separate cycle, the blazingly-bright planet Venus emerged from behind the Sun at its superior conjunction back on October 22, and has been rising higher above the sunset with each passing night. These two bodies are drawing closer toward each other and will soon "meet in the middle," lining up in a beautiful
planetary conjunction. As seen in the pic below, Jupiter and Venus were about 20 degrees apart on February 15, which is about a handspan held at arm's length, the distance between your thumb
and pinky. But these bright bodies will quickly close the gap over the next two weeks. They'll be only about 10 degrees apart this week -- the width of a clenched fist. If you somehow cannot pick out
these bright bodies on your own, watch for the waxing crescent Moon as it passes this pair on the evenings of Tuesday, February 21 and Wednesday, February 22. Jupiter and Venus will draw close more quickly the following week until they are perfectly aligned on the evening of Wednesday, March 1 when they are only a half-degree apart, a mere lunar diameter. So what's going on? What are the "celestial mechanics" behind this planetary line-up? Jupiter is a slower-moving planet than Earth,
circling the Sun in 12 years. The Earth moves 12 tmes that fast in its orbit. So Jupiter remains relatively static in its position among the zodiac, currently poking along through the constellation Pisces, as viewed from the Earth. Because of the Earth's orbital motion, the line-of-sight between the Sun and the background constellations is always shifting, resulting in an apparent movement of the Sun. So the Sun appears to be moving into a position where it will
align with Jupiter in Pisces. But as seen from the Earth, it appears that Jupiter and Pisces are drawing closer to the sunset over the weeks and months. It's all a matter of perspective. (For more info on these topics, please check out Signs & Seasons, our homeschool astronomy curriculum) Jupiter will draw close to the sunset over the remainder of the winter and finally disappear into the sunset. Jupiter will invisibly line up
on the opposite side of the Sun at its superior conjunction on April 11. But we'll lose sight of the bright planet weeks before that alignment. Meanwhile, as mentioned above, Venus had its own superior conjunction
back on October 22, and the faster-moving planet has been moving out of alignment ever since, appearing further away from the Sun and therefore higher above the sunset over the recent weeks and months. So as Jupiter has been dropping lower toward the sunset, Venus has been rising up to meet it. If we could see the invisible orbits of these
planets, we would see the plane of the solar system with Venus circling toward the east as it draws further away from the Sun. But due to the Earth's orbital motion, Jupiter and the background constellations of Pisces and nearby Pegasus are moving west, setting up the planetary rendezvous as their two lines-of-sight converge. So if you have any clear evenings over the next two weeks, make sure to go out
every clear night to observe the buildup to this conjunction. It is most interesting to observe the planetary cycles in action over time, and not just poke your head out on the single night of the actual conjunction. It's exciting to view the
nightly changes in these planetary positions! (Well I think so anyway, but maybe I don't get out much!) But here's the rub -- you have to actually get up out of your comfy chair and slip on your shoes and actually GO OUTSIDE! Don't try to
cheat by looking through a window! That is not as good a view! Take the Classical Astronomy 60 SECOND CHALLENGE and devote at least a full minute of your evening to observing this wondrous pair. Go out in the fading
glow as night falls and look to the west, maybe a half hour after sundown. And while you're at it, take some time to look around at the LORD's beautiful world and enjoy the wonderful ambience of twilight, "brief arbiter 'twixt day and night" according to John Milton, this shortest and most mysterious time of day. The planetary cycles were a source of fascination for millennia by our pre-industrial ancestors, in the days before TV, smartphones and blockbuster popcorn movies with whiz-bang CG special effects. Because of the awe and wonder they felt while gazing at the sky, the ancients recorded the timings of these celestial lineups and began the formal process of empirical study of the sky, which led eventually
to the Scientific Revolution and the modern hi-tech world we enjoy today. It's an historical irony that modern science has created a comfortable wall of technology, an artificial barrier that has severed our natural connection to the starry sky, which
was a familiar part of human life down through all previous centuries of history. Many a scientist began his or her career as a child witnessing the majesty of the celestial clockwork. Maybe your child will also follow this tradition? Further to
previous newsletters (see the archive), the occultation series between the Moon and Mars has ended for the time being, though there will be another in September. But there
will still be the usual monthly lunar conjunctions with Mars. So after the waxing crescent Moon aligns with Venus and Jupiter, be sure to follow its eastward progress across the sky as it approaches Mars when it waxes to First Quarter on Monday, February 27, the day of conjunction. Let me know if your family is able to view any of these beautiful alignments. 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
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