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.
Peace I leave with you, my peace I give unto you: not as the world
giveth, give I unto you. Let not your heart be troubled,
neither let it be afraid. - John 14:27
IN THIS UPDATE
A Few Words About Orion
The "Maximum" Maximum Elongation of Venus
Hello Friends,
Hope everyone is doing well in this difficult time. The current CoronaVirus situation can offer today's generation a glimpse into crises of the past, including Biblical lessons of how great empires can be suddenly laid low. Whatever the actual extent of the viral threat, it is evident that the American (and world) condition has changed a lot in a short period of time. It seems that the USA might also require an
economic recovery in 2020 along with a health recovery.
Whatever the turmoil in the world or in my own life, I often go outside and observe the sky. No matter the troubles on Planet Earth, the Sun, Moon, stars and planets still continue serenely along in their silent cycles, rising and setting, changing with the seasons. They are a stable, unchanging presence in an unstable world of change.
These same celestial bodies shined down in centuries past upon the Black Death, world wars, famines, and woes that are as yet unknown to Americans. They are a reminder to me that they were placed above by Supreme Mind who is working out a plan and that His ways are not our ways. As we contemplate all the problems of the world, we can draw assurance, peace and comfort from observing these movements of of these bright
objects in the heavens.
We pray that you all remain healthy in the coming season, and that this season passes quickly.
On another note, now that travel is limited, we all have more time to observe the sky than ever before! For my own part, I've lived the "social distance" lifestyle for many years, having been a homeschool dad that worked from home since 2005. I'm somewhat amused that people across the USA have now entered my little world! Hey, it's not so bad! You can catch up on your reading, and take time to follow the
weather from day to day, and observe the spring blossoms of the plant life as they burst forth and grown in your own yard.
You can also have a chance to step outdoors and study the cycles of the Sun, Moon, stars and planets. Springtime can be a great time to study the sky. You can watch the days grow longer, and observe the Sun climbing higher into the noon sky. There are many such outdoor activities in our Signs & Seasons curriculum. You
can do them with your kids or even by yourself for your own education. And unlike your favorite restaurant or movie theater, the Classical Astronomy Store will remain open through the duration of the CoronaVirus alert!
A Few Words about Orion
Long time readers of this newsletter and our Signs & Seasons curriculum know that the constellation Orion is a popular subject and a common tool used for teaching a number of astronomy lessons. Like many of you, Orion is my personal favorite constellation, being the most conspicuous star pattern in the sky, perhaps after the
Big Dipper. Orion is unique in so many ways, from it's distinct human shape, to the amazing three stars of Orion's Belt, which is practically a miracle in itself, as we explained in this article.
My own little world was rocked this fall by the dramatic dimming of Betelgeuse, the brightest star in Orion, accordingly designated as α Orionis. For several months, Betelgeuse grew progressively faint, dimming from being the 11th brightest start in the sky to
fainter than nearby Bellatrix, which is the 27th brightest star in the sky.
Having been well acquainted with this star for over 50 years, since I was 8 years old, I found it utterly alarming to observe such a dramatic drop in brightness. According to mainstream science, Betelgeuse will one day explode in a supernova, sometime in the next 100,000 to one million years, according to theory. But scientific theories have a way being proved wrong in the fullness of time. Like many, I feared
that the dimming was a precursor to such a celestial explosion, that the supernova of Betelgeuse would occur now, this year.
As impressive and historic as such a sight might be, it would forever alter the pattern of Orion. The starry Hunter would then be missing a shoulder, and would no longer resemble a human figure. This would forever destroy the familiar star pattern that has been famous in all cultures down through all human history. Orion is prominently mentioned in the writings of the Ancient Greeks, and even older writings,
such as the Book of Job, arguably one of (if not the) oldest extant works of human literature....
Canst thou bind the sweet influences of Pleiades, or loose the bands of Orion? - Job 38:31
I would have been saddened to be a member of the last generation of humanity to know Orion as he has always been known.
Thankfully, Betelgeuse recently began to brighten again, after reaching its faintest in February, 2020. I was cheered just this week to notice that Betelgeuse is once again visibly brighter than Bellatrix. Betelgeuse is known to be variable star, but the recent drop was a historically long and deep period of dimming, the most extreme since the development of photometric measurements in the 19th
century.
No one knows for sure what happened, but a contending theory is that Betelgeuse expanded and shed a layer of hot gas, which cooled into a dark layer of dust that obscured the visibility of the star. Whatever the actual cause, since Betelegeuse is 700 light years from our solar system, the event would have occurred 700 years ago, around the time when Dante was writing The Divine Comedy, and only recently visible on
Earth.
This is another visible lesson for me that there is a profound order to our world, a master plan to things, of which our lives are but a small part, and that we can be assured of our place in the unfathomable will of our Creator.
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.
*****
The "Maximum" Maximum Elongation of Venus
I hope everyone has been enjoying the sight of the blazingly bright planet Venus in the dusk twilight after sunset, shining brilliantly as the Evening Star. Perhaps you have not noticed Venus since it is not at its usual spot hovering above the treetops. Rather, Venus has been soaring high in the evening sky, nearly halfway to the meridian, towering above the landscape. And then Venus has remained
high in the sky after night falls, shining brightly in the night sky for several hours before sinking low and setting.
If you've been an observer of Venus for a while, you might notice that this is unusual behavior for the brightest planet. Venus is usually seen low in the west, grazing the treetops, and then quickly disappearing as night falls.
The current circumstances of Venus occur only every 8 years, and we can think of this as the "maximum" maximum of Venus.
Venus is currently at maximum elongation, a point in its regular cycle when it is furthest from the Sun. The "elongation" of the Moon or a planet is the angular distance from the Sun, as seen from the skies of Earth. The maximum elongation of an inferior planet (i.e., Venus or Mercury) is when the planet is at a point in its orbit that it forms the maximum angular distance from the Sun, appearing furthest
away from the Sun in the sky. (For a detailed explanation of elongations, see our Signs & Seasons curriculum.)
When this happens in the evening, it is called a maximum eastern elongation because Venus extends away from the sunset toward the east. (Conversely, in the morning, it is a maximum western elongation, because the planet extends away from the sunrise toward the west.) At either maximum, Venus can appear over 45 degrees away from the Sun, or halfway to the meridian.
In the cycle of Venus, there are 5 maximum eastern elongations every 8 years. These occur about every one year, seven months apart. There was an evening max in March, 2012, then in November, 2013, followed by June, 2015, then January, 2017, and again in August, 2018, and now back to March in 2020.
March is also the month of the vernal equinox, or the first day of spring for observers in the northern hemisphere. At this spot in the sky, the ecliptic (or the path of the planets) is inclined at a steep angle compared to the celestial equator, which is the frame of reference for the sky. The Sun was at the point of the vernal equinox on March 19, 2020. (Again, all these concepts
are explained in detail in our Signs & Seasons curriculum.)
Anyway, like the Sun, Moon and all the other planets, Venus is always near the ecliptic. But in the evenings of the spring, the ecliptic is steeply inclined toward the north. So when a maximum eastern elongation occurs on a date near the vernal equinox, the path of Venus is very steep to the horizon, and just about sticks straight up above the treeline. So this is the "maximum" maximum eastern elongation of
Venus, which occurs on March 24, 2020. At this time, Venus is nearly halfway to the zenith, the point in the sky directly overheard!
Evening maxes can be pretty high in January, but when they occur in June, August and November, Venus tends to be much lower to the horizon, and this results in the more familiar circumstance of spotting the Evening Star low above the treeline in the dusk twilight after sunset. So take a look in the next week or two (weather permitting) to see Venus at the highest point it will be until 2028.
After this week, Venus will begin to descend in the evening sky, as the planet begins to align with the Sun. Venus will be gone from sight before Memorial Day, as it aligns with the Sun at its inferior conjunction on June 3, 2020. After that date, Venus will reappear in the dawn sky before sunrise, and will once again become the Morning Star.
There is a comet appearing in the sky, Comet ATLAS. It remains to be seen whether this will become a visible comet. If so, I hope to write a newsletter about it. You can check out our Facebook Page for regular updates.
Once again, the Ryan Family wishes you good health and happy days ahead in 2020!
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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