TGT #24W- When Does The Year Actually End? - Start of the Year Moongazing, & More!
TGT 12/15/24: Sky Planning Calendar--Moon Passes Every Evening Planet, or Covers It (Hello, Mars, Bye, Mars!), Ditto Seven Sisters; Deeper Looks--The New Year is Not When You Think (Yikes!)
Cover Photo - 2:42 PM, Happy New Year! (Huh?)
In This Issue:
Cover Photo — 2:42 PM, Happy New Year! (Huh?).
Welcome to Issue 24W!
Sky Planning Calendar —
* Moon-Gazing - Moon Passes or Covers Up Four Brightest Planets, Mars, and Pleiades Spectacularly!* Observing—Plan-et - Mercury Maxes in the Dawn, Venus in the Evening dark; Saturn’s Last Good Month—-and The Same for its Rings.
* Border Crossings - Which Sagittarius Do You Want?Deeper Looks — Is There An Astronomical Way to Know When 2024 Actually Ends?? (Cover Story)
Welcome to The Galactic Times Newsletter-Inbox Magazine #24W!
Greetings, Galactic Timers!
The Fall Tour of book talks on the Marquis de Lafayette and HIS Tour of the USA 200 years ago, the Southeastern part specifically, has ended, but the Winter Tour begins late January and through April. I get 5 whole weeks to rest and recuperate and catch my breath for the New Year. For more Lafayette info, click here to go to https://www.hermograph.com/lafayette . Hopefully TGT will be back on its start/midmonth schedule in mid-January.
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Speaking of New Year, when exactly does the New Year begin —or conversely, when does 2024 END? Is there an astronomical event that dictates when a year begins and ends? There is, there was, and there isn’t. See the Deeper Looks story of this issue.
During the 27 days that this issue will cover, from the Winter (Northern hemisphere) Solstice to January 16th, the evening sky is dominated by close passages of the Moon to bright planets, sometimes covering them up for observers somewhere, and even over a star cluster. Three planets position themselves for peak viewing (one’s already there), and one is about to have more than its final hurrah. See the Sky Planning Calendar.
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We’re ending the year with an online survey. It would be good to know your thoughts on our various articles and columns, and other things. It would be greatly appreciated if you could fill in the anonymous (if you choose) survey that is online here by January 10th. If you complete the survey and leave your email address, you will receive an e-coupon for discounts on the Hermograph Press store (www.hermograph.com/store) for your time. Thanks in advance!
Go to the survey HERE…..
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* Not a Subscriber? Please hit the link..right… below:
Enjoy!
Publisher — Dr. Larry Krumenaker Email: newsletter@thegalactictimes.com
Sky Planning Calendar
Moon-Gazing
Moon passages by a star, planet or deep sky object are a good way to find a planet or other object if you’ve never located it before.
December 22 Last Quarter Moon.
December 24 The Moon is at Apogee, its far point in its orbit, and also at the location of the bright white star Spica. At some point in the morning, depending on where you are, they will be 0.2-degrees apart, less than half a Moon diameter. Most North Americans will find it the Moon to the right of the star.
December 28 The slim crescent Moon is barely a tenth of a degree south of the summer star Antares, in the dawn, see simulation above. It is covered up if you are in the FAR northern parts of Russia, North America, or Europe. Nearby is Mercury, rising at the same time as Antares, circa 5:40 AM though they will be easier to see as they rise higher into the sky.
December 30, 2024 New Moon. The end of the lunar phase cycle today is a good time to end the lunar month/calendar year/solar year in sync.
January 3, 2025 The Moon begins a two-week passage near four bright planets, in some cases OVER the planet, and even a star cluster. If you get/got a telescope for the holidays, this is a good time to learn to find these objects AND even watch them disappear or reappear. Today you can find brilliant Venus 1.4-degrees away from the Moon, and about at its maximum possible distance from the Sun—47-degrees. See below.
January 4 The Moon’s second passing by a bright planet, Saturn—the least bright of all right now—by 0.7-degrees (the Moon is sized within a bit of a half-degree, for comparison) is tonight. It will pass over the ringed planet for observers in Florida, much of Latin America, and part of Europe. Look NOW as the planet will not only disappear from the evening sky in around a month, but this will be your LAST TIME to see the Northern (upper) side of the Rings until 2039. Again, see below.
January 6 First Quarter. This will be a larger than average half-moon because….
January 7 ….the Moon will be at Perigee, its closest point to the Earth.
January 9 Starting from evening twilight hours through about 9 PM Central Time (adjust for your time zone location), the Moon will go through the main asterism of a mini-dipper that the brightest stars of the Pleiades star cluster form. With a telescope, watch the stars as the Moon approaches them….and blink out before the lit part of the Moon actually gets to them. Now you see them, whoops! Now you don’t.
January 10 The Moon passes widely past the King of the Planets, Jupiter, by five whole degrees, the third passage in this sequence.
January 13 Full Moon.
January 13-14 The most spectacular of the planetary cover-ups (occultations) this month is the fourth passage, the Moon over Mars. In some places the Moon passes 0.2-degrees south of it, but for virtually all of North American, plus Western Africa, you can watch Mars get covered up slowly by the Moon’s bright edge, and even more fun, try to figure out where on its other bright edge it will come out. The Moon is only a few hours past Full so there is no real dark limb to the Moon. This will begin around 8PM Central Time or after by up to a half hour, end from minutes to an hour or more later.
Observing---Plan-et
==Mars Spectacularly Covered Over by Moon==
==Planets to the Max—Solar Elongations and Oppositions==
Mercury almost has the dawn to itself, with only reddish Mars up on the opposite western side of the sky. Mercury reaches its maximum distance from the Sun, 20-21-degrees to the West of it, on December 25th, Christmas Day. If you get up really early, around the start of morning twilight to check for Santa’s speedy delivery, take a peek in the East for Mercury, the planet named in honor of the speediest Greek god, and also the god of merchants, who should all be genuflecting this day towards him. Talk about a star in the East…..
Seven degrees to its south (right) will be summer star Antares. In fact, the two briefly share the dark morning pre-twilight skies as Mercury rises before twilight begins, a rarity, from December 17 to 29th. It remains easily visible and actually brightening as the weeks progressed even as it drops deeper into the solar glare. The crescent moon is close by on December 28th. Mercury remains visible all of January.
Venus is Queen of the Night now, reaching its maximum distance from the Sun of 47-degrees on January 9th, remaining that bright star in the West for hours into the evening, and during this whole issue time and for two more months. The Moon passes nearby on January 3rd, a photogenic event. In a telescope it is a featureless, slightly gibbous moon-shape but it slims down to a half-moon appearance at Greatest Elongation day, and a thick crescent thereafter. Over this time span of January easily watch it approach Saturn.
Earth has two key dates this month.
December 21—Shortest day for latitude 40 degrees North…AND….Solstice occurs at 3:20 AM US Central Time. See our Deeper Looks article below on the connection of solstice and year’s ending.
January 4—Perihelion, when the Earth is closest to the Sun. For those who didn’t get the lesson in elementary school, this is when Northern Hemisphere weather is coldest (more or less) because the Earth’s north pole is tipped away from the Sun. So unlike camping around a fire, it isn’t the Earth’s distance from the Sun that controls the average temperature, it is that the Earth’s north pole is pointing away from the Sun, which diffuses the amount of heat/energy per square area. This is opposite to the Southern Hemisphere which DOES have its Pole pointing towards the Sun.
Coincidentally, Earth gets hit by the peak of the Quadrantid meteor shower occurs on January 3rd, a very strong but extremely short duration shower. Total time, 14 hours—7 on each side of the peak which can number over 100 per hour but the rate rises and falls rapidly on each side of the peak. This year the peak is around 9AM so look in the pre-dawn hours to get anything. The Moon will not interfere with meteor watching but clearly the Sun will. Clearly this year the shower peak is good for North America’s West Coast and further beyond in the Ocean.
Meteor showers get their names from the constellation they appear to radiate out of, so what is the Quadrantid constellation? It is an obsolete constellation, Quadrans Muralis, the Quadrant, a constellation that went out of existence in the early 1800s. Named for the pre-telescopic era measuring device shaped as a ninety-degree quarter-circle, it was located between the upper part of Bootes the Herdsman and the handle end of the Big Dipper.
Mars is the final planet to enter the evening sky show. It rises at the end of evening twilight on New Year’s Eve and it will reach Opposition to the Sun on January 15-16th. Then it will rise as the Sun sets, and vice versa, up all night. Interestingly, it is at its closest to Earth on the 12th. Why? Because Mars’ orbit is even more eccentric (non-circular) than Earth’s and our orbital axes are not in line. So it is actually moving away from us when it is exactly opposite the Sun, i.e. when there is a straight line from Sun to Earth to Mars.
As mentioned above, the Moon covers over the Red Planet in a spectacular way on the night of the 13th-14th.
Jupiter is visible ALL night, at least until December’s end after which it sets at or before morning twilight starts. The Moon passes nearby to Jupiter on the 10th. But anytime is a good time to use a telescope to see Jupiter’s cloudy atmosphere and even (new Christmas) binoculars can track its 4 bright moons.
Saturn sets well before local midnight. The Moon passes it on the 4th. The planet only has another month or so to be part of the evening sky show. More importantly, the thin rings you see in your telescope are getting thinner….because of perspective. As we will have our Equinox in March, when the Sun goes from South of our Equator to North, so does Saturn, relative to Earthly views. In March the rings go edgewise to Earth and we will no longer see the Northern side of the Rings of Saturn. For the next 14 years we will see the underside, the Southern side, of the Rings when they appear in future months. Unfortunately, that edge-on ring appearance when the planet will resemble a paler shade of Jupiter will occur as Saturn is too close to the Sun in our sky. Look now, and compare in the dawn sky in six months.
Border Crossings
The Sun is naturally at its lowest point, the Solstice, on the 21st. It has been in Sagittarius since December 18th and will remain there this whole issue date, until January 18th when it enters Capricornus.
Astrologers have the Sun in Sagittarius on the December 21st issue date of this Galactic Times. However they say it enters Capricornus the next day, until the 19th of January when, after one day of overlap with astronomy, it ‘enters’ Aquarius. Right….
Deeper Looks: Is There An Astronomical Way to Know When 2024 Actually Ends??
The calendar says the year—any year—ends when December 31st ticks over to January 1st, at local midnight. We are so used to it that we give it no particular thought at all. But why then? Is that even accurate?
No, to the second question.
The official clock on this planet is in Greenwich, England—known as Universal Time, UT, or Greenwich Mean Time, GMT—so when the Big Apple falls in the Big Apple, the new year is actually already 5 hours old. OK, you can have one official moment for all the computers and astronomers to agree on. But why that date?
It wasn’t always.
And that brings us to the natural end date in the past.
The Sky Motion of the Sun
Astronomically, the date of the Winter Solstice in the Northern Hemisphere was a natural fit for ending/beginning years. The Winter Solstice is the date of the Sun’s lowest noon altitude and diurnal passage in the sky, the least amount of daylight in our 24 hours of day, and the lowest amount of Sun’s energy we’re going to get.
Plants that we need to live on have died, it is cold, water turns to undrinkable ice in the North, animals hibernate, and so on. To more primitive cultures, getting ol’ Sol to not sink any further was believed to be a necessary act to avoid extinction and doing it with celebrations, worship, rites was the way to convince it to reverse its descent. And those always worked. The Sun would begin a slow climb up back to higher altitudes the next day. Thus a new year could begin that date.
But it wasn’t always December 21st for the Solstice either. It should have been, in modern parlance, December 31st, but our calendar, first officially legislated was in Roman times, the Julian Calendar named for Julius Caesar. The Roman calendar was 365 days long, but that doesn’t synchronize well with Earth’s rotation; the year is actually 365.25 days—approximately. So, every four years a new day would have to be inserted into the calendar, our Leap Year day, to bring the calendar and those four quarter-days back in line. But even that was not quite right because Earth actually rotates in 23 hours, 56 minutes and 4 seconds, as referenced to the stars. That four minutes difference adds up over the centuries. Leap days can be added in, and sometimes not, during the first year of a new century to account for them, but it still doesn’t quite align with nature or the sky.
By the Middle Ages, the passage of solstices and equinoxes, and the facts of weather and nature were days apart, in some ways, months. Pope Gregory XIII in 1582 added ten days to the calendar, setting off massive protesting. “We want our ten days of life back!” Countries were slow to adopt the calendar change; we might today worry about converting Zoom meeting times across time zones, here we’re talking about which day in your Julian or Gregorian calendars do we meet? Some countries did not adopt the Gregorian calendar until well into the 1900s!!
But this ten-day addition pushed the End of Year to a new date, December 31st, and not when the Solstice actually happened.
Thus we lost the astronomical connection, right?
Not completely. But it’s gotten more complicated.
A Point in Our Orbit
If the Earth’s rotation period is measured by when a star is, say, at its highest altitude above ground, on two consecutive Earth rotations, is there an equivalent for the annual revolution period?
Yes.
Several equivalents.
Since New Year’s Eve (or Day) is no longer equivalent to Solstice Day, what can we use? By analogy to how we define Earth’s rotation, can we define our revolution period as the time it takes to get to the day the Earth returns to the same orbital position the year started in? Yes, sort of.
Orbital position is measured as the Earth’s heliocentric position, how far around the Sun we are in a 360-degree longitude-like coordinate. In the sky visible from Earth, we look to the Sun (metaphorically speaking), and measure its geocentric coordinate (its Ecliptic longitude) which arbitrarily starts on where the Sun is as seen from Earth on the Vernal Equinox. That is the 0-longitude point in the sky, the so-called First Point of Aries. But we, planet Earth and Sun, are 180-degrees opposite each other, in a similar system, the solar system’s heliocentric longitude 180 then. We need the two coordinates for December 31st when the clock ticks over to January 1st.
A computer program called MICA from the US Naval Observatory—the American equivalent to Greenwich Observatory—can calculate that. As 2024 turns to 2025 the Earth is at heliocentric longitude 100 degrees, 28 minutes of arc (there are 60 minutes of arc per degree) and 12.6 seconds of arc (60 of those per minute of arc), written as 100d 28m (or 28’) and 12.6s (or 12.6”). You’ll find the Sun 180-degrees around the sky from this, at Ecliptic longitude 280-degrees and change.
Aargh, that’s not always the case, though. Other years it is at slightly different longitude values. That extra day thing still gets in the way.
But perhaps we can agree on a standard place, the average place that Earth is, on New Year’s Eve/Day. The extreme range from 2025 to 2029 turns out to be from 100d 28m 12.6s down to 99d 41m 15s. The mid-point thus comes out to be 100d 4m 30s in Earth’s heliocentric longitude.
So 2025 will begin when the Earth reaches heliocentric longitude 100d 4m 30s. And that’s midnight in Greenwich, UK. Right?
Wrong again.
And the Party is When?
That’s actually 2:42 PM, New Year’s Day 2025. A late picnic lunch that London-area afternoon. 8:42 AM in New York. Fireworks at breakfast.
This year, 2024, actually began at 10:42 AM UT on December 31st— in 2023—in the official time capital of the world. 4:42 AM in New York, almost 24 hours earlier before the Big Apple falls in Times Square!! So technically, 2024 had no official moment of New Year’s!! It started in 2023, ends in 2025.
But wait, it gets worse. It also depends on your definition of a year!
Our Sidereal Year (fixed star to fixed star) as we had defined it is 365.256363 days. Translation, the extra quarter day is actually 6 hours…and 9 minutes long.
If you measure the year from Equinox to Equinox (or the equivalent of Solstice to Solstice) the Tropical Year is 365.242189 days, only an additional 5.81 hours more than 365 days, an extra 5 hours and 48 minutes. We get to the next Equinox earlier, and twelve minutes short of a quarter day. The change is caused by the precessing, like a tipped-over spinning top, of the Earth’s axis, which changes very slowly the position of where the axis points in the sky, currently near Polaris, the North star.
But it also changes all the constellations’ locations—everywhere—including along the Sun’s path in the sky, the Ecliptic, and those well-known Zodiac constellations. That First Point of Aries? It is in Pisces these days. This motion is small but continuous, and cumulative. That’s why the constellations as discussed in the Border Crossings article every issue rarely match the horoscope signs.
Oh, wait, the Earth’s orbit ALSO slowly precesses, and in the opposite direction. We measure this by two consecutive passages of the Earth reaching perihelion twice, its closest point in its elliptical orbit to the Sun. That is 365.259 days in an Anomalistic Year, or an extra 6 hours and 13 minutes. The next Perihelion occurs January 4th this coming 2025. Have another New Year celebration!!
And all these extra motions-the changing tilt of the polar axis, the precession of the Ecliptic and pole, the precession of our orbit—add together.
So what? Well, if you don’t account for these plus and minus minutes, your celebration moment cumulatively gets way off, until at least the next Leap Day. Even so, we’ll someday need a new (Papal?) calendar correction if we don’t.
Meanwhile, Happy New Year, whenever you want to celebrate it…….
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And Finally….
Til next issue (on January 17, 2025),
Happy holiday, whatever holiday makes you happy!
Dr. Larry Krumenaker