Unfortunately, there are still some drivers out there who apparently don’t know how to treat pedestrians with the respect that they deserve.
But this little dog is doing his best to set them straight.
The other day, Beqa Tsinadze happened upon a curious scene in the town of Batumi, Georgia. There, at a clearly marked crosswalk, a group of young kids were waiting for cars to yield so they could safely cross the road.
Photo Credit: Beqa Tsinadze
Regrettably, though, it seems that many drivers weren’t eager to extend that courtesy without being told to.
So, that’s exactly what this dog did — taking on the role of crossing guard on the kids’ behalf. The moment was captured on video.
The thoughtful dog tackled the situation like a pro. But apparently this wasn’t just a one-time thing.
Tsinadze shared another video of the same dog stopping traffic and escorting yet another group of kids across the street.
Photo Credit: Beqa Tsinadze
Though it’s unclear why the pup came to adopt the role of crossing guard, it may be as a way of saying thanks.
According to Georgian media, the dog arrived to the area as a helpless stray a few years back, and has since endeared himself to members of the community who have taken it upon themselves to care for him.
The report above states that the dog goes by several names among folks in the neighborhood who know him — but there’s no doubt that you’d be safe in calling him a very good boy.
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Another wonderful report.
I’m sorry, I ought to write more but I would only be waffling!
Interesting article about calculating a dog’s age.
It’s a well-known ‘calculation’ that a dog’s age is seven years for every human year. But it’s wrong; the scientific result is more complex.
But rather than me say it, I’ll hand it over to Christian Yates of the BBC who on the 6th January this year published an article on this subject.
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Your pet clearly ages faster than you do, but new research is giving us a much clearer idea of just how old your dog really might be.
By Christian Yates, January 6th, 2020
If your dog has been alive and kicking its paws about for a decade, the widely held belief is it has aged as much as a human would have done over 70 years. This conversion factor – each year of a dog’s life accounting for seven human years – comes from dividing human life expectancy of around 77 by the canine life expectancy of around 11.
The underlying assumption is that each calendar year a dog lives through is equivalent to seven human years at any stage of a dog’s life. But new research suggests that things aren’t so simple. And if we look at some basic developmental milestones, it’s clear why.
For example, most dog breeds reach sexual maturity between the ages of six and 12 months – the upper end of that range corresponding, by the traditional conversion, to a human age of seven. And at the other end of the spectrum, although unusual, some dogs have been known to live for over 20 years. Under the “factor-of-seven” conversion rule, this would equate to an unfathomable 140 human-equivalent years.
New insights into how dogs age suggest our pets move into middle age more rapidly than most owners might suspect (Credit: Getty Images)
To make matters more complicated, dogs’ life expectancy depends significantly on the breed. Smaller dogs tend to live significantly longer, suggesting that they age more slowly than bigger dogs.
All of this raises the question of what exactly we mean by age. The most obvious way to describe it is simply the length of time that has passed since birth. This is known as the chronological definition of age.
When it comes to comparing animal ages across species, the biological definitions of age are far more useful than their chronological counterparts
However, there are other descriptions. Biological age, for example, is a more subjective definition, which relies on assessing physiological indicators to identify an individual’s development. These include measures like the “frailty index” – surveys that take into account an individual’s disease status, cognitive impairments and levels of activity.
Rather than celebrating chronological age, looking at the levels of methylation on a dog’s DNA is a much more accurate measure of aging (Credit: Getty Images)
For example, if you’ve spent a lot of time eating junk food and smoking cigarettes instead of taking exercise and eating healthily, the chances are your biological age will exceed your chronological age. Or, you might be a 60-year-old with the body of a 40-year-old if you’ve looked after yourself well.
A dog’s life
When it comes to comparing animal ages across species, the biological definitions of age are far more useful than their chronological counterparts. Knowing a hamster is six weeks old doesn’t give you a good picture of that animal’s life stage, even if you know the life expectancy of a hamster is only three years. Learning that a hamster has reached an age where it can reproduce gives a much better picture of its level of maturity.
In their first year of life, puppies grow up so quickly that they age the equivalent of 31 human years (Credit: Getty Images)
In particular, “methylation” – the addition of methyl groups (a carbon atom bonded to three hydrogen atoms) to DNA – seems to be a good indicator of age. Many prominent physiological markers, such as the development of teeth, seem to occur at the same levels of methylation across different species. So by matching the levels of methylation in Labrador retrievers and humans, the researchers derived a formula to map dog age to its human equivalent.
That formula is: human equivalent age = 16 x ln(dog’s chronological age) + 31.
Here “ln” represents a mathematical function known as the natural logarithm. The logarithm function is well-known in the non-linear scales for energy released during earthquakes (Richter) or for measuring sound (decibels). It comes in useful for measuring quantities whose sizes vary over many orders of magnitude. It’s even possible that a logarithmic experience of the passing of time might explain why we perceive time speeding up as we get older.
A handy short cut is to remember that the first dog year counts for 31 human years
In the graph below, you can see how the natural logarithm works to convert the years a dog has lived (dog age) into the equivalent human age in the red dashed curve. The curve suggests that dogs mature extremely rapidly at first, but that their ageing then slows down, meaning that most of their lives are experienced as a form of protracted middle age.
A handy short cut is to remember that the first dog year counts for 31 human years. Then, after that, every time the dog’s chronological age doubles, the number of equivalent human years increases by 11. So eight calendar years represents three “doublings” (from one to two, two to four and then four to eight) giving a dog age equivalent of 64 (that’s 31 + 3×11).
This useful approximation is plotted as the black curve on the conversion figure below. The green line represents the discredited factor-of-seven rule that suggests unrealistic ages at the higher end of the dog age spectrum.
In eight calendar years a dog will approximately age the equivalent of 64 years (Credit: Christian Yates)
Most dog lovers will already have suspected that the human-to-dog age relationship is non-linear, having noticed that, initially, their pets mature much more quickly than the linear factor-of-seven rule suggests.
A more sophisticated refinement to the factor-of-seven rules has suggested that each of the dog’s first two years correspond to 12 human years while all subsequent years count for four human equivalents. The blue curve in the above figure, which represents this ad hoc rule, shows better agreement with the new logarithmic law.
In practice the new molecular insights into human-to-dog age conversion encapsulated by the logarithmic law suggest that dogs move into middle age even more rapidly than most dog-owners would have suspected. It’s worth bearing in mind, when you find that Rex is reluctant to chase the ball like he once did, that he’s probably got more miles on the clock than you’ve been giving him credit for.
Christian Yates is a senior lecturer in mathematical biology at the University of Bath. He is also the author of The Maths of Life and Death.
This articleoriginally appearedon The Conversation, and is republished under a Creative Commons licence.
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I don’t know about you but I found this article extremely interesting.
Playing a game of fetch with a dog means they are following a human social cue to recover the ball. But fetch isn’t just for dogs, wolf puppies are down to play too, which means they can also understand human communication cues, according to a new study.
Credit Wikipedia Commons
The findings, published in the journal iScience, were made after researchers put 13 8-week-old wolf puppies from three different litters through a series of tests usually used to assess dog-puppy behavior. Three of the pups were interested in playing fetch with a stranger, which included bringing a ball back when encouraged to.
The discovery was quite a surprise for the team as it was believed that the cognitive abilities necessary to understand communication cues given by a human were presented in dogs only after humans domesticated them 15,000 years ago. Dogs differ from wolves physically, genetically and behaviorally.
“When I saw the first wolf puppy retrieving the ball, I literally got goosebumps,” said Christina Hansen Wheat of Stockholm University in a press release. “I immediately knew that this meant that if variation in human-directed play behavior exists in wolves, this behavior could have been a potential target for early selective pressures exerted during dog domestication.”
Wanting to learn more about the effects of domestication on behavior, Hansen Wheat and her team raised wolf and dog puppies from the age of 10 days and put them through various behavioral tests. In one of them, the pup was thrown a ball by an unknown person, encouraging the wolf to get it and bring it back.
Expectations of the wolf pups catching on weren’t high, with the first two litters showing no interest in the balls, let alone of playing fetch. But everything changed with the third litter. A few of the puppies went for the ball and even responded to the social cues and brought it back.
“It was very surprising that we had wolves actually retrieving the ball,” said Hansen Wheat. “I did not expect that. I do not think any of us did. It was especially surprising that the wolves retrieved the ball for a person they had never met before.”
In the past, other research showed that domesticated and non-domesticated species will follow human gestures if a food reward is given, Hansen Wheat and her team said. But in those cases, the animals were previously trained to follow the cues or knew the person conducting the study.
While the new research has a limitation over the size of its sample, it could reassess our interpretation that understanding human social cues came from domestication. Instead, it could be possible that this behavior can be traced back to an ancestral population before wolves were domesticated into dogs.
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Despite this being the twenty-first century there are still things being discovered that cause us humans to be amazed.
Such as this story about the young wolves, way before they evolved into dogs.
The following was sent to me by Chris Gomez, brother of Dan, who I have known for nearly as long as Dan (and that’s a long time)!
The article appeared on ZME Science was published on the 15th January. It contains material that I, for one, didn’t know and I suspect I’m not the only one.
Have a read.
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Why do dogs have whiskers?
Whiskers allow dogs to “see” things that are literally under their noses.
Many mammals, including canines, have whiskers. Some dog owners think these whiskers are just longer unruly hairs that can be groomed and even snipped off entirely — but this would be a huge mistake. The whiskers, technically known as “vibrissae”, serve important specialized functions that help dogs sense the world around them and coordinate their movement.
Humans sense touch through millions of sensory receptors that line the skin and deeper tissue. Unlike humans, the follicles of the coarse hairs protruding from a dog’s muzzle, jaw and above its eyes are also packed with nerves that relay sensory information.
Essentially, these whiskers allow dogs to sense objects and the world around them as humans do with fingers.
What are a canine’s whiskers good for
Credit: Wikimedia Commons.
The tactile sensation is made possible thanks to Merkel cells, which are specialized skin receptors associated with nerve terminals. A dog’s mouth and snout are very rich in Merkel cells, according to a study published in the journal Veterinary Science.
According to researchers, these tactile hairs serve a variety of functions. For instance, the whiskers allow dogs to gather information from subtle changes in air currents about size, shape, and speed of nearby objects. Ultimately, this allows canines to see their surroundings better, even in dark. It’s well known that vision isn’t a dog’s strong point, so their vibrissae greatly assist them — especially when dealing with close objects (dogs are farsighted). Whiskers beneath the chin allow dogs to “see” objects obstructed by their snouts.
Whisker’s positioned immediately above the eyes are particularly important for vision. When an object or strong airflow causes these whiskers to flex, dogs will reflexively blink in order to protect their eyes.
It’s not clear whether dogs use their whiskers for food acquisition. However, if they’re anything like rats, seals, and walruses — all related species that have been shown to use their whiskers to find food — dogs might very well use their sensing hairs for this purpose, too.
A dog’s whiskers can also serve an important role in communication with other canines or other species. Like many other mammals, when a dog is threatened it will automatically flare its whiskers, pointing them in a forward direction. This signals to predators and other aggressive animals that the dog is ready to defend itself and respond with violence.
Dogs may use their whiskers to also disperse pheromones, keep their head upright when swimming, and monitor their environment.
About 40% of a canine’s visual cortex (the part of the brain responsible for processing vision) is devoted to mapping information from whiskers. They’re that important!
What you need to know about your dog’s whiskers
Credit: Pxfuel.
Although they might look similar, vibrissae are distinct from body hair. The main difference is that a dog’s whiskers are directed by the nervous system and contain nerves.
Unlike cats, which have four rows of whiskers on either side of a cat’s face, the placement of a dog’s whiskers is less predictable. Some have a multitude of vibrissae, others may have few or even none. You should find them above the eyes, on both sides of the muzzle, above the upper lip (pointing down) and beneath the dog’s chin.
According to scientists, there are no breed-specific differences in canine whiskers. An exception may involve hairless breeds, which have no whiskers at all.
That being said, you should never trim your dog’s whiskers. Some pet owners believe their dogs’ whiskers should be groomed and snip them for aesthetic purposes.
This practice won’t hurt the dog, because there are no pain receptors found in whiskers. However, given the multitude of functions they serve, a whisker-less dog will become confused, disorientated, and less able to navigate its spatial surroundings. If you cut your dog’s whiskers in the past out of ignorance, know at least that they will grow back naturally.
In summary, dogs use their whiskers as a sort of radar to detect objects that they cannot properly see with their own eyes.
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Apart from the fact that the photographs are gorgeous there is much material that is good to know. For instance, I never knew there were no breed-specific differences in canine whiskers. Just hadn’t thought about it before.
Yesterday and today are days where it’s my turn to do the neighborhood watch patrols. I left for the first patrol a little after 9am yesterday and when I was going up Livingston Drive there was a guy walking his Corgi. Now it’s the second time we have met and I stopped and let the sweet dog come up to my outstretched hand and sniff my fingers. John, not his real name, mentioned that he was slowly adapting to a life of love and affection in stark contrast to the beatings the dog received in his previous life. John was a real hero!
Here’s another example of goodness beyond description. Taken from The Dodo.
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Dog Found On Side Of Road Immediately Snuggles Her Rescuer
Photo Credit: Kris Lenker
Kris Lenker and her husband were driving home from work last week when they spotted something on the road ahead.
They assumed, being out in the country, that the small, tan animal was a baby deer — but as they got closer, they realized their mistake. “We slowed down and realized that it was a dog,” Lenker told The Dodo.
Lenker hopped out of the car and called to the dog, but the nervous pup took off down a pathway. Lenker followed close behind, tempted to turn around. “I couldn’t see her anymore and we almost left,” Lenker said. “I just had a feeling, though.”
Photo Credit: Kris Lenker
Lenker found the dog hiding behind a fence, and after a few minutes of gentle pets, the nervous dog decided to take a chance. “She wrapped her front paws around my neck and let me carry her back to the car,” Lenker said. “She was absolutely terrified, but I could tell she trusted me … It just felt like we were brought together for a reason.”
Shortly after the dog entered the car, her demeanor changed. It was as if she knew she was finally safe. “I just pet her and told her I had her,” Lenker said. “That is when she just collapsed into a ball in my lap. It’s like relief just hit her. She rode the rest of the way home in my lap like that.”
Photo Credit: Kris Lenker
While she decompresses and regains her strength, the dog, whom the couple has named Reba, is hanging out in a warm bathroom. When she’s up to it, she’ll get to meet her new dog siblings, who will show her the rules of the house.
And Reba is still just as affectionate as the first day they found her: “Belly rubs are her favorite, and she doesn’t hesitate to ask for them!” Lenker said. “She rolls on her back and paws at us until we give in.”
Reba was initially resistant to being rescued, but now she doesn’t want to leave — even to go outside for potty training. She demands that her mom carries her outside and back in every time.
Photo Credit: Kris Lenker
“I think she is still afraid she will be left out there,” Lenker said.
It’s only been a few days, but already Reba has been putting on weight and learning what it means to have a real family. “Her energy level is so much better and she is the biggest love bug,” Lenker said. “All she wants to do is snuggle us and give us kisses. It’s her favorite thing to do.”
Lenker believes they were truly meant to have Reba as part of their family. “She wouldn’t let anyone get near her, but she let us take her,” Lenker said. “She trusts us so much and we have fallen in love.”
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“She trusts us so much and we have fallen in love.” What a fabulous end result.
There are so many loving people out there that would do the same. It’s an honour to present this account.
It was published on the Majestic Animals website and I hope republishing it is OK.
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Dog accidentally runs half-marathon after being let out for pee, finishes 7th
Sports are great for the health and running is the best way to keep you in a good shape. But I just can’t imagine to train hard for a 13 miles marathon, only to have a dog beat you. Well, that is exactly what happened with most of the Elkmont Trackless Train Half Marathon runners, in Alabama.
Ludivine, a 2 years old Bloodhound was out for a pee when she spotted all those guys running. And since there wasn’t any rule to say that only humans re allowed to participate, the quick thinker pup joined the marathon. Surprisingly, that wasn’t all as the doggy not just finished the run, but she even got a medal.
The adorable dog who finished seventh in the race, even had some pit stops!
She finished in just over an hour-and-a-half. Her owner April Hamlin said:
“All I did was open the door, and she ran the race on her own accord. My first reaction was that I was embarrassed and worried that she had possibly gotten in the way of the other runners. She’s laid back and friendly, so I can’t believe she ran the whole half marathon because she’s actually really lazy.”
Jim Clemens, who finished fourth in the half marathon said, “Every time I thought she had dropped off to go back home, I would hear her coming back up to me and she would race past me up to the two leaders. She would run off to romp through the streams and into yards to sniff around for a while.”
After the week I’ve had, I so needed this story! Check the video below!
I have written quite a few times about the eyes of dogs but never the wolf.
This was sent to me by Julie Thomas-Smith, the wife of my best friend, Richard Maugham, and it is just beautiful.
It comes from the Wolf Conservation Center and when one goes across to that website then one reads:
A wolf’s eyes have the power to speak a great language. Did you know that wolves possess certain ocular characteristics that allow them to communicate with other members of their species using their eyes alone? One can guess that this gives a new meaning to the common phrase “puppy-dog eyes!”
But all dog owners know that the odds of anxiety or depression if you have a dog or two around one are greatly reduced.
I’m chairing a discussion on depression at our local Humanists and Freethinkers group in eighteen days time; on January 18th, 2020. The core of my talk is a TED Talk given journalist Johann Hari in July of 2019.
This is how the talk is introduced.
In a moving talk, journalist Johann Hari shares fresh insights on the causes of depression and anxiety from experts around the world — as well as some exciting emerging solutions. “If you’re depressed or anxious, you’re not weak and you’re not crazy — you’re a human being with unmet needs,” Hari says.
There are sufficient numbers of people who follow this blog that it is likely that this talk will really engage a few of you. It’s twenty minutes long and very interesting!
Science has maybe found a clue to the ancestor of the dog and the wolf.
For an animal that means so much to us humans, the origins of the dog are still uncertain. Indeed, as this interesting article shows, the origins of the wolf are uncertain.
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Was This 18,000-Year-Old Puppy Frozen in Siberian Permafrost the Ancestor of Wolves, Dogs or Both?
DNA tests on the well-preserved remains can’t determine whether the little canine was wild or domestic
(Sergey Fedorov/NEFU)
By Jason Daley, smithsonianmag.com
Dec. 3, 2019, 10 a.m.”>December 3, 2019
Meet Dogor, an 18,000-year-old pup unearthed in Siberian permafrost whose name means “friend” in the Yakut language. The remains of the prehistoric pup are puzzling researchers because genetic testing shows it’s not a wolf or a dog, meaning it could be an elusive ancestor of both.
Locals found the remains in the summer of 2018 in a frozen lump of ground near the Indigirka River, according to the North-Eastern Federal University in Yakutsk. Parts of the animal are incredibly well-preserved, including its head, nose, whiskers, eyelashes and mouth, revealing that it still had its milk teeth when it died. Researchers suggest the animal was just two months old when it passed, though they do not know the cause of death.
The pup is so well-preserved that researchers at the Centre for Palaeogenetics in Sweden were able to sequence the animal’s DNA using a piece of rib bone. The results found that Dogor was male, but even after two rounds of analysis the team could not determine whether he was a dog or a wolf.
“It’s normally relatively easy to tell the difference between the two,” David Stanton, a Centre for Palaeogenetics research fellow, tells Amy Woodyatt at CNN. “We have a lot of data from it already, and with that amount of data, you’d expect to tell if it was one or the other. The fact that we can’t might suggest that it’s from a population that was ancestral to both—to dogs and wolves.”
The find is exciting, regardless of whether Dogor turns out to be a common canine ancestor, an early dog, or an early wolf. Hannah Knowles at The Washington Post reports that Dogor comes from an interesting time in canine evolution, when wolf species were dying out and early dogs were beginning to emerge.
“As you go back in time, as you get closer to the point that dogs and wolves converge, [it becomes] harder to tell between the two,” Stanton tells Knowles.
(Sergey Fedorov/NEFU)
The history of just how and when dogs split from wolves is unresolved. There’s a general agreement among scientists that modern gray wolves and dogs split from a common ancestor 15,000 to 40,000 years ago, explains Brian Handwerk previously for Smithsonian.com. How dogs became dogs, however, is contested. Some research suggests that dogs were domesticated by humans once, while other studies have found dogs were domesticated multiple times. Exactly where in the world wild canines became man’s best friend is also disputed. The origin of the human-animal bond has been traced to Mongolia, China and Europe.
Scientists disagree about how dogs ended up paired with people, too. Some suspect humans captured wolf pups and actively domesticated them. Others suggest that a strain of “friendly,” less aggressive wolves more or less domesticated themselves by hanging out near humans, gaining access to their leftover food.
Dorgor’s DNA could help unravel these mysteries. The team plans to do a third round of DNA testing that may help definitively place Dogor in the canine family tree, report Daria Litvinova and Roman Kutuko at the Associated Press.
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This is incredibly interesting, don’t you think?
Hopefully I will hear of that third round of DNA testing and, if so, will most definitely share it with you.
Posted by Deborah Byrd in Astronomy Essentials | Earth|December 15, 2019
December solstice 2019 arrives on December 22 at 4:19 UTC.
That’s December 21 for much of North America. High summer for the Southern Hemisphere. For the Northern Hemisphere, the return of more sunlight!
Ian Hennes in Medicine Hat, Alberta, Canada, created this solargraph between a June solstice and a December solstice. It shows the path of the sun during that time period.
Late dawn. Early sunset. Short day. Long night. For us in the Northern Hemisphere, the December solstice marks the longest night and shortest day of the year. Meanwhile, on the day of the December solstice, the Southern Hemisphere has its longest day and shortest night. The 2019 December solstice takes place on Sunday, December 22, at 04:19 UTC (That’s December 21 at 10:19 p.m. CST; translate UTC to your time).
No matter where you live on Earth’s globe, a solstice is your signal to celebrate.
When is the solstice? The solstice happens at the same instant for all of us, everywhere on Earth. In 2019, the December solstice comes on December 21 at 10:19 p.m. CST. That’s on December 22 at 04:19 Universal Time (UTC). It’s when the sun on our sky’s dome reaches its farthest southward point for the year. At this solstice, the Northern Hemisphere has its shortest day and longest night of the year.
Just remember: you’re translating from 04:19 UT on December 22. For example, if you live in Perth, Australia, you need to add 8 hours to Universal Time to find out that the solstice happens on Sunday, December 22, at 12:19 p.m. AWST (Australian Western Standard Time).
Day and night sides of Earth at the instant of the December 2019 solstice (December 22, 2019, at 04:19 UTC). Image via EarthView.
What is a solstice? The earliest people on Earth knew that the sun’s path across the sky, the length of daylight, and the location of the sunrise and sunset all shifted in a regular way throughout the year. They built monuments such as Stonehenge in England – or, for example, at Machu Picchu in Peru – to follow the sun’s yearly progress.
But we today see the solstice differently. We can picture it from the vantage point of space. Today, we know that the solstice is an astronomical event, caused by Earth’s tilt on its axis and its motion in orbit around the sun.
Because Earth doesn’t orbit upright, but is instead tilted on its axis by 23 1/2 degrees, Earth’s Northern and Southern Hemispheres trade places in receiving the sun’s light and warmth most directly. The tilt of the Earth – not our distance from the sun – is what causes winter and summer. At the December solstice, the Northern Hemisphere is leaning most away from the sun for the year.
At the December solstice, Earth is positioned in its orbit so that the sun stays below the North Pole horizon. As seen from 23 1/2 degrees south of the equator, at the imaginary line encircling the globe known as the Tropic of Capricorn, the sun shines directly overhead at noon. This is as far south as the sun ever gets. All locations south of the equator have day lengths greater than 12 hours at the December solstice. Meanwhile, all locations north of the equator have day lengths less than 12 hours.
For us on the northern part of Earth, the shortest day comes at the solstice. After the winter solstice, the days get longer, and the nights shorter. It’s a seasonal shift that nearly everyone notices.
Earth has seasons because our world is tilted on its axis with respect to our orbit around the sun. Image via NASA.
Where should I look to see signs of the solstice in nature? Everywhere.
For all of Earth’s creatures, nothing is so fundamental as the length of daylight. After all, the sun is the ultimate source of all light and warmth on Earth.
If you live in the Northern Hemisphere, you can notice the late dawns and early sunsets, and the low arc of the sun across the sky each day. You might notice how low the sun appears in the sky at local noon. And be sure to look at your noontime shadow. Around the time of the December solstice, it’s your longest noontime shadow of the year.
In the Southern Hemisphere, it’s opposite. Dawn comes early, and dusk comes late. The sun is high. It’s your shortest noontime shadow of the year.
Around the time of the winter solstice, watch for late dawns, early sunsets, and the low arc of the sun across the sky each day. Notice your noontime shadow, the longest of the year. Photo via Serge Arsenie on Flickr.Meanwhile, at the summer solstice, noontime shadows are short. Photo via the Slam Summer Beach Volleyball festival in Australia.
Why doesn’t the earliest sunset come on the shortest day? The December solstice marks the shortest day of the year in the Northern Hemisphere and longest day in the Southern Hemisphere. But the earliest sunset – or earliest sunrise if you’re south of the equator – happens before the December solstice. Many people notice this, and ask about it.
The key to understanding the earliest sunset is not to focus on the time of sunset or sunrise. The key is to focus on what is called true solar noon – the time of day that the sun reaches its highest point in its journey across your sky.
In early December, true solar noon comes nearly 10 minutes earlier by the clock than it does at the solstice around December 22. With true noon coming later on the solstice, so will the sunrise and sunset times.
It’s this discrepancy between clock time and sun time that causes the Northern Hemisphere’s earliest sunset and the Southern Hemisphere’s earliest sunrise to precede the December solstice.
The discrepancy occurs primarily because of the tilt of the Earth’s axis. A secondary but another contributing factor to this discrepancy between clock noon and sun noon comes from the Earth’s elliptical – oblong – orbit around the sun. The Earth’s orbit is not a perfect circle, and when we’re closest to the sun, our world moves fastest in orbit. Our closest point to the sun – or perihelion – comes in early January. So we are moving fastest in orbit around now, slightly faster than our average speed of about 18.5 miles per second (30 kilometers per second). The discrepancy between sun time and clock time is greater around the December solstice than the June solstice because we’re nearer the sun at this time of year.
Solstice sunsets, showing the sun’s position on the local horizon at December 2015 (left) and June 2016 (right) solstices from Mutare, Zimbabwe, via Peter Lowenstein.
The precise date of the earliest sunset depends on your latitude. At mid-northern latitudes, it comes in early December each year. At northern temperate latitudes farther north – such as in Canada and Alaska – the year’s earliest sunset comes around mid-December. Close to the Arctic Circle, the earliest sunset and the December solstice occur on or near the same day.
By the way, the latest sunrise doesn’t come on the solstice either. From mid-northern latitudes, the latest sunrise comes in early January.
The exact dates vary, but the sequence is always the same: earliest sunset in early December, shortest day on the solstice around December 22, latest sunrise in early January.
And so the cycle continues.
Solstice Pyrotechnics II by groovehouse on Flickr.
Bottom line: The 2019 December solstice takes place on Sunday, December 22, at 04:19 UTC (that’s December 21 at 10:19 p.m. CST; translate UTC to your time). It marks the Northern Hemisphere’s shortest day (first day of winter) and Southern Hemisphere’s longest day (first day of summer). Happy solstice, everyone!
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Well for many in the Northern Hemisphere the worst of the winter weather is yet to come.
Learning from Dogs 