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.
Praise ye him, all his angels: praise ye him, all his hosts. Praise ye him, sun and moon: praise him, all ye stars of light. Praise him, ye heavens of heavens, and ye waters that be above the heavens. -- Psalm 148:2-4 IN THIS
UPDATE Venus and Mars -- Conjunctions and Opposition The Full Moon Opposition Occultation of Mars Hello Friends, We've had some beautiful fall weather this year on the normally cloud-enshrouded shores of the Great Lakes. It's so unsual to see blue skies in December, when the Sun is so low in the sky and even the noon shadows stretch long and far. I never grow tired of observing
the annual cycle of the seasons, it's an ongoing source of wonder which has blessed my life. Jupiter is shining brightly in the evening skies, high up at the meridian in the hours after dark, while Saturn has
begun declining toward the sunset. Clear skies permitting, check out the Geminid meteor shower on December 13 and 14. The waning Moon should permit
early evening darkness for meteor watching. Winter begins at 4:48 PM EST on December 21, the moment when the Sun reaches its most southerly point in the sky. This date is the winter solstice for the northern hemisphere. For a detailed discussion of the solstices, check out our Signs & Seasons astronomy curriculum. In other news, I rejoined Twitter this past week. I had a Twitter account since 2008 that I deleted in 2020 to protest Big Tech censorship. I'm hopeful that recent developments with the new owner will result in a more positive environment for free speech on this platform. If you're on Twitter, please follow me @JayRyanAstro and I'll follow you back. This will be the last newsletter for
2022, so let me wish you all a joyous and blessed Christmas, from the Ryan Family to yours! If you have not yet
done so, check out our new and improved Book Trailer video for our Signs & Seasons astronomy curriculum, and share this newsletter with your friends: 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. ***** Venus
and Mars - Conjunctions and Opposition As mentioned in the previous newsletter, the red planet Mars is currently prominent in the evening sky, and is approaching opposition. And after a long morning apparition, the blazingly bright planet Venus has passed superior conjunction and is returning to the evening sky. So what do these fancy words mean? They both describe times when planets lie along a straight line with the Earth and the Sun. Whenever planets are in conjunction with the Sun, they lie along the same line of sight as the Sun and are invisibly lost in the Sun's glare. All the planets pass through superior conjunction when they line up on the far
side of the Sun as viewed from Earth, behind the Sun's bright light. The inferior planets -- Venus and Mercury -- have times of inferior conjunction when they line up in between the Earth and the Sun, and are in front of the Sun. The superior planets -- Mars, Jupiter and Saturn -- reach opposition when the Earth is lined up between the planet and the Sun. For a detailed discussion of oppositions and solar conjunctions, check out our Signs & Seasons astronomy curriculum. The superior conjunction of Venus occurred back on October 22. Since that time, this planet has been moving out of alignment from the Sun, and
now appears to the east of the Sun, having an eastern elongation. Thus, Venus is still visible above the horizon after sunset in the dusk twilight. The faster-moving planet moves further out of solar alignment over the coming weeks and months, and will therefore be increasing in eastern elongation. As Venus increases in eastern elongation, it appears higher and higher in the evening sky after sunset. Venus shines as The Evening
Star, the brightest object visible in the sky after the Sun and Moon. In early December, the eastern elongation of Venus is only about 10 degrees. So Venus is still quite close to the Sun's glare and is not yet conspicuous in the bright dusk twilight glow. So Venus is barely above the horizon by the time the twilight dims sufficiently. But by month's end, the eastern elongation of Venus will increase to 20 degrees, and it should be an easy sight after sunset and
thereafter into the New Year. If you have clear skies on Christmas Eve -- December 24 -- make a note to check shortly after sunset when the bright planet Venus will be joined by
a very thin crescent Moon. This will be the first of a series of monthly lunar conjunctions of Venus that will continue into 2023. If the twilight is dim enough and if you have sharp eyes, try to spot the elusive planet Mercury which joins the Moon and Venus in a Christmas Eve trio, a beautiful little triangle of celestial objects. In case you forget to check on Christmas Eve, make it a point to follow Classical Astronomy on one or more social media platforms where we will (hopefully!) be posting timely reminders. The Full Moon Opposition Occultation of Mars Wow, that's a mouthful! Look at all those big words! I've never written a headline like that before because I don't recall such a unique celestial event as will occur this week on Wednesday December 7. That date is notable for the annual commemoration of the Pearl Harbor attack (and Dr. Parson's birthday) but this year it will mark a multiple combined astronomy event. As explained above, the superior planets reach opposition when the faster-moving Earth reaches a point in its orbit where it passes between the planet and the Sun. At such times, the planet is at a spot in the sky "opposite" the Sun as viewed from Earth, hence the
name. So as the Sun sets at a given location, Mars rises at the opposite point in the sky, 180 degrees away from the Sun. Mars reaches opposition about every two years or so. At opposition, Mars and the Earth are closest than at any other time. Mars
therefore appears at its brightest in the night sky. In 2022, Mars brightens to magnitude -1.9, brighter than Sirius, the brightest actual star, and approaching the brightness of Jupiter, which is the fourth brightest object in the sky after Venus, the Sun and the Moon. This year, the opposition of Mars occurs in Taurus, near the famous constellation Orion. Having a distinct rusty-red color, Mars will really stand out at this opposition in this
well-known and popular part of the sky. It also happens that the Full Moon is the opposition of the Moon, when the lunar luminary is 180 degrees away from the Sun at the opposite horizon from the sunset. The
precise time of the Full Moon opposition is 11:00 PM on December 7, while the hour of the opposition of Mars is 1:00AM, a mere two hours afterwards. The Moon and Mars will both reach opposition at almost the same time, and will both be simultenously occupying the same place in the sky. When that happens, the result is an occultation of Mars by the Moon. A lunar occultation occurs when the Moon covers over a star or planet and "hides" it for a time. (The word "occultation" comes from the Latin word which means "to hide." It is a scientific term that does not mean the same thing as "the occult" i.e., magic or the diabolical arts, even though it has the same etymology.) For a
detailed discussion of occultations, check out our Signs & Seasons astronomy curriculum. During this occultation, the Moon will draw very close to Mars, and then will touch the edge of Mars, after which will entirely cover over the planet and hide it for a time. It is not very common to have a lunar conjunction of a planet visible from the United States. It happens every few years and often occurs at rude hours in the middle
of the night. I've never heard of an occultation of Mars at opposition by a Full Moon, when both bodies are at their brightest. (The odds must be comparable to those of a Royal Fizzbin!) And as if all that's not enough, this event will be visible over most of the USA and an early hour of the evening when most folk are still up and around. So there's no excuse to pass up this sky event, clear skies permitting, of course. This linked page to the IOTA website shows the visibility of this lunar occultation of Mars over the Earth, where it is
visible over North America including much of the northern USA and all of the western USA. Occultations are really cool as the light of the planet grows dim and then winks out as the Moon covers over it. It's a neat
sight in binoculars or a telescope, especially if you can observe the precise moments of disappearance and/or reappearance. The timings of the occultation varies depending on your location. The linked page has a long list of locations around the world including times of disappearance and reappearance. The page is not set up in the most "user-friendly" manner but it includes over 1500 cities, so odds are your town is listed, or at
least the nearest metropolis. I recommend loading the page and using "Control-F" in the browser window to search for a selected town. The times are given in Universal Time (UT) as is common in astronomy circles.
This is the same as Greenwich Mean Time, which is 5 hours ahead of Eastern Standard Time. So if you live in the eastern time zone, subtract 5 hours from the indicated times to find your local times for disappearance and reappearance. For example, for my home of Cleveland, Ohio, Mars disappears at 3:26:04 UT, which is about 10:26 PM EST, and reappears at 4:05:31 UT, which is about 11:05 PM. The times of occultation also vary by location, with the duration being longer where Mars disappears along the widest part of the Moon, and shorter where Mars is closer to the edge. For example, the occultation will be long in San Francisco, California where Mars vanishes at 2:34:56 UT (or about 6:35
PM PST) and reappears at 3:55:35 UT (or about 7:55 PM PST). The timing variations are also due to differences in visual parallax between the Moon and Mars as seen from different places on Earth. This subject
is too involved to delve into here. Though I've not lately continued the "flat earth" debunking series, it's worth considering that the occultation timing calcuations are based on the assumption that the Earth is a globe 8000 miles in diameter, and that the Moon is a 2000 mile diameter sphere 240,000 miles away. Such precise numbers would not be accurate if the Earth were flat and if the Moon were a 32 mile wide ball hovering 3000 miles overhead. I hope to explain more
about parallax in an upcoming newsletter. As can be seen from the map on the above linked page, this occultation will miss the southeast, the Gulf states and the east coast. But don't be sad, friends! You will still be blessed with a VERY close lunar conjunction with Mars, which will still be a very beautiful and amazing sight in this famous part of the sky. Hope you'll still
go outside and take a peek. Please drop an email and send along a report if anyone sees this sight. Better yet, pass along any nice pix that you're able to snap. There are some unique and special events to witness in the evening sky this month, hiding in plain sight, so please share this email newsletter with your family and friends and encourage them to subscribe and stay informed. Hope you all can see these beautiful celestial Christmas presents that the LORD has placed FOR FREE in the sky above this month! Wishing everyone a blessed Christmas season and a wonderful new year ahead in 2023! 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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