An essay about the 2020 winter solstice!
Winter solstice 2020 in the Northern Hemisphere will be at 2:02 AM on Monday, December 21. That is our local Pacific Time which is 8 hours behind UTC.
So in UTC terms that is 10:02.
For some reason I have always regarded the Winter solstice as special, no doubt because in the Northern Hemisphere it is the time for the shortest day! It is the start of the new year!
What you need to know about this year’s winter solstice and the great conjunction
December 18, 2020
By William TeetsActing Director and Astronomer, Dyer Observatory, Vanderbilt University
Editor’s note: Dr. William Teets is the director of Vanderbilt University’s Dyer Observatory. In this interview, he explains what does and doesn’t happen during the winter solstice on Dec. 21. Another cosmic phenomenon is also going to occur on the same day called “the great conjunction,” where Saturn and Jupiter, both of which can be seen with the naked eye, will appear extremely close to one another.
What happens on the winter solstice?
The winter solstice this year happens on Dec. 21. This is when the Sun appears the lowest in the Northern Hemisphere sky and is at its farthest southern point over Earth – directly over the Tropic of Capricorn. For folks living at 23.5 degrees south latitude, not only does this day mark their summer solstice, but they also see the Sun directly over them at local noon. After that, the Sun will start to creep back north again.
The sequence of images below shows the path of the Sun through the sky at different times of the year. You can see how the Sun is highest in the Northern Hemisphere sky in June, lowest in December, and halfway in between these positions in March and September during the equinoxes.
The winter solstice is the shortest day in the Northern Hemisphere but not the day with the latest sunrise and earliest sunset. How is that possible?
The winter solstice doesn’t coincide with the latest sunrise or the earliest sunset. Those actually occur about two weeks before and two weeks after the winter solstice. This is because we are changing our distance from the sun due to our elliptical, not circular, orbit, which changes the speed at which we orbit.
If you were to look at where the Sun is at exactly the same time of day over different days of the year, you would see that it’s not always in the same spot. Yes, the Sun is higher in the summer and lower in the winter, but it also moves from side to side of the average noontime position, which also plays a role in when the Sun rises and sets.
One should also keep in mind that the seasons are due to the Earth’s axial tilt, not our distance from the Sun. Believe it or not, we are closest to the Sun in January.
What is ‘the great conjunction’?
Saturn and Jupiter have appeared fairly close together in our sky throughout the year. But on Dec. 21, Saturn and Jupiter will appear so close together that some folks may have a difficult time seeing them as two objects.
If you have a pair of binoculars, you’ll easily be able to spot both planets. In even a small telescope, you’d see both planets at the same time in the same field of view, which is really unheard of. That’s what makes this conjunction so rare. Jupiter and Saturn appear to meet up about every 20 years. Most of the time, however, they’re not nearly as close together as we’re going to see them on Monday, Dec. 21.
For a comparison, there was a great conjunction back in 2000, but the two planets were separated by about two full-Moon widths. This year, the orbits will bring them to where they appear to be about one-fifth of a full-Moon diameter.
We have been encouraging folks to go out and look at these planets using just their eyes between now and Dec. 21. You’ll actually be able to see how much they appear to move over the course of a single day.
The next time they will get this close together in our sky won’t be for another 60 years, so this is going to be a once-in-a-lifetime event for many people. In fact, the last time they got this close together was in the year 1623, but it was really difficult, if not impossible, to see them then because they appeared much closer to the Sun and set soon after it. Go back another 400 years to 1226 and this would have been the last time that we would have had a good view of this type of conjunction.
What advice would you give to people who want to see the great conjunction?
If weather permits at Dyer Observatory, we’ll be streaming a live view of the conjunction from one of the observatory’s telescopes, and I’ll be available to answer questions. Even if you don’t have a telescope or a pair of binoculars, definitely go out and check out this very rare alignment with your own eyes. Remember that they set soon after sunset, so be ready to view right at dusk!
ooOOoo
From the introduction that was received by email:
I want to include another piece on the conjunction. It comes from the introduction to that item above: It’s been a tough year. To many of us, every day during the coronavirus pandemic has felt incredibly long. Perhaps it will come as a relief that Monday will be the shortest day of the year. December 21 will also bring a rare cosmic phenomenon. If the sky is clear over the next few nights, look out just over the southwest horizon. You may see Jupiter and Saturn coming together and then drifting apart in an event known as “the great conjunction.” Although this occurs once every two decades, the last time they came this close, and we Earthlings got such a clear view, was in 1226.
I also want to include a copy of an article on the website belonging to KRCC that talks of the Great Conjunction.
Why The Jupiter And Saturn Conjunction During The 2020 Winter Solstice Is Extra Special
The conjunction of Jupiter and Saturn appears over Cheyenne Mountain in Colorado Springs. Jupiter appears brighter and to the lower right of Saturn. Saturn, to Jupiter’s upper left, has a slightly golden hue. Photo taken December 5, 2020. The planets will be closer than they have been observed from earth in over 800 years on the Winter Solstice
A rare celestial event will help mark the Winter Solstice in the northern hemisphere on Monday, Dec. 21.
Jupiter and Saturn are currently appearing very close together from an earthly vantage point. These two gas giants are in conjunction, an occurrence that happens every 20 years or so.
This one though, is extra special.
“Really, really close conjunctions like this one are quite rare,” said Hal Bidlack with the Colorado Springs Astronomical Society. “We haven’t been able to observe Jupiter and Saturn this close since the year 1226. And we won’t see them again this close for decades and decades to come.”
The two planets were last about this close together in the year 1623. But the pairing occurred while the planets were close to the sun from earth’s perspective, Bidlack said, and the sight was basically washed out in the sun’s glare.
In reality, Saturn and Jupiter are hundreds of millions of miles apart.
“On the 21st they will appear so close that if you held a dime on edge at arm’s length, that’s how close they would be together,” Bidlack said.
From Colorado Springs, sky gazers only need to look toward Cheyenne Mountain to catch a glimpse. Elsewhere in Colorado, Bidlack said folks can look to the southwestern skies, low near the horizon.
The pair sets around an hour and a half after the sun does, about 4:39 p.m. on Monday.
The planets will begin to separate when viewed from Earth, and will eventually disappear altogether from the night sky until reappearing in the morning sky in early 2021. See more skywatching tips from NASA.
If you have managed to stay on today’s post until near the end you would have seen the following: “We haven’t been able to observe Jupiter and Saturn this close since the year 1226. And we won’t see them again this close for decades and decades to come.”
Just about 800 years ago since this last happened.
If you can, go outside with a telescope or a pair of binoculars and watch the sight! That time of the sunset is 4:39 PM Pacific Time. I think that wherever you are in the world starting to watch as soon as it is dark would be a good idea.
You all understand that this blog, while predominantly about our special doggie friends, never hesitates to wander away from matters canine if I think it will be enjoyed by all you good people.
You will also all appreciate that August is the month where in the USA, on August 21st, there will be a total eclipse of the sun.
The reasons why I didn’t hesitate to republish a recent post that was presented on Mother Nature Network.
ooOOoo
What to see in the night sky in August
While the total solar eclipse is the highlight, there are other celestial fireworks to look forward to this month.
Celestial events for August 2017 include a total solar eclipse, Perseid meteor shower and the rise of the Sturgeon Moon. (Photo: Michael Seeley/Flickr)
Welcome to August, a month defined by loud cicadas, pool parties, humidity and children fretting about an impending return to school. When it comes to celestial happenings, however, there is no larger star this month that our own moon. From a partial lunar eclipse to the first coast-to-coast solar eclipse in almost a century, the moon will be the cause of most eyeballs drifting towards the heavens over the next several weeks.
Below is a small sampling of some of the night and day celestial events to look forward to this month. Wishing you all clear skies!
The rise of the full Sturgeon Moon (Aug. 7)
The full Sturgeon Moon is so-named for the fish that are easily caught in August and early September. (Photo: Paul Kline/flickr)
August’s full moon, nicknamed the Sturgeon Moon, will rise for the U.S. Eastern Seaboard on the evening of Aug. 7 at 8:05 p.m.
The Sturgeon Moon gets its name from the species of fish native to both Europe and the Americas that is easily caught this time of year. Other nicknames include the Corn Moon, Fruit Moon and Grain Moon. In countries experiencing winter, such as New Zealand, native Māori called this full moon “Here-turi-kōkā” or “the scorching effect of fire is seen on the knees of man.” This reference is to warm fires that glow during the Southern Hemisphere’s coldest month.
Partial lunar eclipse (Aug. 7 & 8)
Observers in Africa, Asia and Australia will see August’s partial lunar eclipse in its entirety. (Photo: Forrest Tanaka/flickr)
As a kind of consolation prize for missing out on this month’s total solar eclipse over North America, those living on the continents of Africa, Asia and Australia will bear witness to a partial lunar eclipse. Spectators in Europe will catch the tail end of the eclipse as the moon rises around 7:10 p.m. on Aug. 7.
This phenomenon occurs between two to four times a year when the moon passes through a portion of the Earth’s shadow. Because the shadow cast is more than 5,700 miles wide, lunar eclipses last much longer than solar eclipses. In some instances, totality can occur for as long as 1 hour and 40 minutes. As a reference, maximum totality for the Aug. 21 solar eclipse will top out a mere 2 minutes and 42 seconds. The longest, at over 7 minutes, won’t take place until the year 2186.
This month’s partial lunar eclipse is the last of the year. Next year, total lunar eclipses will take place in January and July.
Perseid meteor shower (Aug. 12)
A composite shot of last year’s Perseid meteor shower over Turkey. Notice how the path of the meteors appears to race from the constellation Perseus. (Photo: NASA)
Regarded as one of the best celestial light shows of the year, the Perseid meteor shower occurs from July 17 to Aug. 24 and peaks on the evening of Aug. 12.
The shower, sometimes creating as many as 60 to 200 shooting stars per hour, is produced as Earth passes through debris left over from the orbit of Comet Swift-Tuttle. This 16-mile-wide periodic comet, which completes an orbit around the sun every 133 years, has been described as “the single most dangerous object known to humanity.” This is because every instance of its return to the inner solar system brings it ever closer to the Earth-moon system. Though astronomers believe the comet bears no threat for at least the next 2,000 years, future impacts cannot be ruled out.
If the comet were to hit Earth, scientists believe Swift-Tuttle would be at least 27 times more powerful than the asteroid or comet that wiped out the dinosaurs. For now, you can take in the beauty of the debris from this harbinger of doom by looking north towards the constellation Perseus. Because the moon will be three-quarters full, you’ll need to search out a nice dark sky to escape any light pollution from urban environments.
Total solar eclipse (Aug. 21)
A total solar eclipse as captured over the Southern Hemisphere in November 2012. (Photo: NASA Goddard Space Flight Center)
Total solar eclipses occur when the new moon moves between the Earth and the sun and casts its shadow on the planet. This shadow is comprised of two concentric cones –– the larger penumbra, which from Earth only shows the sun partially blocked, and the much smaller umbra, which blocks the sun completely. It is within this latter cone that totality will occur, giving spectators on the ground what’s considered by many to be a “once-in-a-lifetime” experience.
The Great American Eclipse will actually first start out in the Pacific (at this point, it will actually, unbelievably rise while completely eclipsed!), making landfall on the Oregon community of Lincoln Beach at 10:16:01 a.m. (PDT). From there, the moon’s shadow will continue to race across the U.S. The point of greatest eclipse, where the axis of the moon’s shadow passes nearest to the center of Earth, will take place in Hopkinsville, Kentucky and last 2 minutes and 40.1 seconds. In celebration of the event, the town has temporarily renamed itself “Eclipseville,” and expects anywhere from 55,000 to 150,000 tourists to visit in advance of Aug. 21.
The next total solar eclipse over the U.S. will take place on April 8, 2024.
New moon (Aug. 21)
August’s new moon will not only create a show during the day, but also leave the heavens to glow unimpeded by night. (Photo: Coconino National Forest/flickr)
Fresh after wowing the U.S. during the day with its solar theatrics, August’s new moon will give way to dark skies for the next several nights. This is the perfect opportunity to grab a blanket and head outside into the still-warm summer evenings to enjoy the heavens in all their glory. With some remnants of the Perseids still visible, it will also offer a chance to catch some of the faintest shooting stars.
Look for Earth’s shadow (All year)
The Earth’s shadow and ‘Belt of Venus’ as captured above Mauna Kea, Hawaii. (Photo: Jay El Eskay/flickr)
Ever wonder what causes the beautiful bands of color in the eastern sky at sunset or the western sky at sunrise? The dark blue band stretching 180 degrees along the horizon is actually the Earth’s shadow emanating some 870,000 miles into space. The golden-red portion, nicknamed the “Belt of Venus,” is Earth’s upper-atmosphere illuminated by the setting or rising sun.
Now that you know about this phenomenon, choose a night or morning sometime to try and pick it out. You’ll need a western or eastern horizon that’s fairly unobstructed to get a clear view of our planet’s huge curved shadow.
Looking ahead to September
On Sept. 15, the Cassini spacecraft will end its 20-year mission to Saturn with a dramatic death dive into the ringed planet. (Photo: NASA)
As fall beckons, the biggest event next month will be the dramatic death dive of the Cassini spacecraft into Saturn. Taking place on Sept. 15, Cassini will make discoveries about Saturn right up until its fiery conclusion, with unprecedented photos and data captured and transmitted during its final moments.
ooOOoo
It is going to be quite a month!
Oh, and for those of you that want to know the timings of the eclipse over North America there is a useful reference site here, from which I republish the following table.
Eclipse Start & End: Local Time for US States
The eclipse will begin over the Pacific Ocean at 15:46 UTC, which corresponds to 8:46 am Pacific Time. It will reach the coast of Oregon at Lincoln City, just west of Salem, at 9:04 am local time. The eclipse will reach its maximum point here at 10:17 am.
From here, the Moon’s central shadow will move inland. The following table shows when the Moon will begin to move in front of the Sun and the moment it completely covers the Sun, as seen from some locations along the central path of the eclipse. All times are local.
Please note that this list includes only a small selection of locations where the total eclipse will be visible. You can look up more locations in our Eclipse Database or via the Eclipse Map.
Enjoy your nights out there! And let your dogs howl their hearts out!
Does rather serve to remind us of our place in the scheme of things.
This stunning image was taken by the Cassini-Huygens probe. Many of the images taken by NASA are available for download from the DVIDS website, which is where this one was found. (But also do visit the Ciclops website.)
The title of the photograph is:
A View of Earth from Saturn
Although the Earth Observatory typically reserves ”Image of the Day” space for publishing data and images acquired by Earth-observing satellites, we are sometimes so enthralled by the spectacular images acquired by spacecraft observing other parts of the solar system that we want to share these ‘otherworldy’ views with our visitors. And if you are looking for remotely sensed images of the Earth, this view is the most remotely sensed image we have ever published!
This beautiful image of Saturn and its rings looks more like an artist’s creation than a real image, but in fact, the image is a composite (layered image) made from 165 images taken by the wide-angle camera on the Cassini spacecraft over nearly three hours on September 15, 2006.
Scientists created the color in the image by digitally compositing ultraviolet, infrared, and clear-filter images and then adjusting the final image to resemble natural color. (A clear filter is one that allows in all the wavelengths of light the sensor is capable of detecting.) The bottom image [the one above. Ed.] is a closeup view of the upper left quadrant of the rings, through which Earth is visible in the far, far distance.
On this day, Saturn interceded between the Sun and Cassini, shielding Cassini from the Sun’s glare. As the spacecraft lingered in Saturn’s shadow, it viewed the planet’s rings as never before, revealing previously unknown faint rings and even glimpsing its home world. Seen from more than a billion kilometers (almost a billion miles) away, through the ice and dust particles of Saturn’s rings, Earth appears as a tiny, bright dot to the left and slightly behind Saturn.
Although it might appear that Earth is located within Saturn’s outermost rings, that positioning is just an illusion created by the enormous distance between Cassini and Earth. When Cassini took this image, the spacecraft was looking back at Saturn from a distance of about 2.2.million kilometers (about 1.3 million miles). The Sun was millions of additional miles beyond, hidden behind Saturn. On September 15, Earth’s orbit had brought our home planet to a location slightly behind and to the left of the Sun from Cassini’s perspective. The Website of the Cassini Imaging Central Laboratory for Operations (CICLOPS) provides more detailed information about this image. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency, and the Italian Space Agency.
Trying to find that faint image of Planet Earth in the above photograph is a challenge, even for those with much younger eyes than mine.
However, with a little bit of jiggery-pokery I was able to crop and enlarge the photograph, see below:
Planet Earth is in the ’10 o’clock’ position in the photograph, about half-way from the centre of the enlarged segment towards the top-left corner of the picture, just outside the outer white ring.
That’s us. All that we have ever been. All that we ever will be. Just that small white dot.
Acting Director and Astronomer, Dyer Observatory, Vanderbilt University
Learning from Dogs 