Why the New Year begins on January 1

Children in Hong Kong wear 2018 glasses during New Year’s Eve celebrations. Image via Kin Cheung/ AP/ Aljazeera.com.

The date of a new year isn’t precisely fixed by any natural or seasonal marker. Instead, our celebration of New Year’s Day on January 1 is a civil event. That’s despite the fact that, for us in the Northern Hemisphere where the amount of daylight has ebbed to its lowest point and the days are getting longer again, there’s a feeling of rebirth in the air.

Our modern celebration of New Year’s Day stems from an ancient Roman custom, the feast of the Roman god Janus – god of doorways and beginnings. The name for the month of January also comes from Janus, who was depicted as having two faces. One face of Janus looked back into the past, and the other peered forward to the future.

To celebrate the new year, the Romans made promises to Janus. From this ancient practice comes our tradition of making New Year’s Day resolutions.

Best New Year’s gift ever! EarthSky moon calendar for 2018

Janus the doorkeeper via tablesbeyondbelief.

January 1 hasn’t been New Year’s Day throughout history, though. In the past, some New Year’s celebrations took place at an equinox, a day when the sun is above Earth’s equator, and night and day are equal in length. In many cultures, the March or vernal equinox marks a time of transition and new beginnings, and so cultural celebrations of a new year were natural for that equinox. The September or autumnal equinox also had its proponents for the beginning of a new year. For example, the French Republican Calendar – implemented during the French Revolution and used for about 12 years from late 1793 to 1805 – started its year at the September equinox.

The Greeks celebrated the new year on the winter solstice, the shortest day of the year.

Today, although many do celebrate New Year’s Day on January 1, some cultures and religions do not. Jews use a lunar calendar and celebrate the New Year on Rosh Hashana, the first day of the month of Tishri, which is the first month of their calendar. This date usually occurs in September.

Most are also familiar with the Chinese New Year, celebrated for weeks in January or early February. In 2018, the Chinese New Year of the Dog begins on February 16.

By the way, in addition to the longer days here in the Northern Hemisphere, there’s another astronomical occurrence around January 1 each year that’s also related to Earth’s year, as defined by our orbit around the sun. That is, Earth’s perihelion – or closest point to the sun – happens every year in early January. In 2018, perihelion comes on January 3.

Image credit: NASA

We don’t celebrate New Year’s Day on January 1 for this reason, but it would make sense if we did. Perihelion – our closest point to the sun in our yearly orbit – takes place each year around January 3. Image via NASA

Bottom line: The reason to celebrate New Year’s Day on January 1 is historical, not astronomical. The New Year was celebrated according to astronomical events – such as equinoxes and solstices – eons ago. Our modern New Year’s celebration stems from the ancient, two-faced, Roman god Janus, after whom the month of January is also named. One face of Janus looked back into the past, and the other peered forward to the future.



from EarthSky http://ift.tt/2iSC5Ag

Children in Hong Kong wear 2018 glasses during New Year’s Eve celebrations. Image via Kin Cheung/ AP/ Aljazeera.com.

The date of a new year isn’t precisely fixed by any natural or seasonal marker. Instead, our celebration of New Year’s Day on January 1 is a civil event. That’s despite the fact that, for us in the Northern Hemisphere where the amount of daylight has ebbed to its lowest point and the days are getting longer again, there’s a feeling of rebirth in the air.

Our modern celebration of New Year’s Day stems from an ancient Roman custom, the feast of the Roman god Janus – god of doorways and beginnings. The name for the month of January also comes from Janus, who was depicted as having two faces. One face of Janus looked back into the past, and the other peered forward to the future.

To celebrate the new year, the Romans made promises to Janus. From this ancient practice comes our tradition of making New Year’s Day resolutions.

Best New Year’s gift ever! EarthSky moon calendar for 2018

Janus the doorkeeper via tablesbeyondbelief.

January 1 hasn’t been New Year’s Day throughout history, though. In the past, some New Year’s celebrations took place at an equinox, a day when the sun is above Earth’s equator, and night and day are equal in length. In many cultures, the March or vernal equinox marks a time of transition and new beginnings, and so cultural celebrations of a new year were natural for that equinox. The September or autumnal equinox also had its proponents for the beginning of a new year. For example, the French Republican Calendar – implemented during the French Revolution and used for about 12 years from late 1793 to 1805 – started its year at the September equinox.

The Greeks celebrated the new year on the winter solstice, the shortest day of the year.

Today, although many do celebrate New Year’s Day on January 1, some cultures and religions do not. Jews use a lunar calendar and celebrate the New Year on Rosh Hashana, the first day of the month of Tishri, which is the first month of their calendar. This date usually occurs in September.

Most are also familiar with the Chinese New Year, celebrated for weeks in January or early February. In 2018, the Chinese New Year of the Dog begins on February 16.

By the way, in addition to the longer days here in the Northern Hemisphere, there’s another astronomical occurrence around January 1 each year that’s also related to Earth’s year, as defined by our orbit around the sun. That is, Earth’s perihelion – or closest point to the sun – happens every year in early January. In 2018, perihelion comes on January 3.

Image credit: NASA

We don’t celebrate New Year’s Day on January 1 for this reason, but it would make sense if we did. Perihelion – our closest point to the sun in our yearly orbit – takes place each year around January 3. Image via NASA

Bottom line: The reason to celebrate New Year’s Day on January 1 is historical, not astronomical. The New Year was celebrated according to astronomical events – such as equinoxes and solstices – eons ago. Our modern New Year’s celebration stems from the ancient, two-faced, Roman god Janus, after whom the month of January is also named. One face of Janus looked back into the past, and the other peered forward to the future.



from EarthSky http://ift.tt/2iSC5Ag

2017 SkS Weekly Climate Change & Global Warming Digest #52

Happy New Year!... Story of the Week... Analysis of the Week... Toon of the Week... Quote of the Week... Coming Soon on SkS... Poster of the Week...  SkS Week in Review... 97 Hours of Consensus...

Happy New Year!

2017 Poster 52 

Happy New Year from the all-volunteer, SkS author team!


Story of the Week...

How We Know It Was Climate Change

Houston Floding_Hurricane Harvey Sep 2017 

Flooding south of Houston in September in the wake of Hurricane Harvey. Credit Barbara Davidson for The New York Times

This was a year of devastating weather, including historic hurricanes and wildfires here in the United States. Did climate change play a role? Increasingly, scientists are able to answer that question — and increasingly, the answer is yes.

My lab recently published a new framework for examining connections between global warming and extreme events. Other scientists are doing similar research. How would we go about testing whether global warming has influenced the events that occurred this year?

Consider Hurricane Harvey, which caused enormous destruction along the Gulf Coast; it will cost an estimated $180 billion to recover from the hurricane’s storm surge, high winds and record-setting precipitation and flooding. Did global warming contribute to this disaster?

The word “contribute” is key. This doesn’t mean that without global warming, there wouldn’t have been a hurricane. Rather, the question is whether changes in the climate raised the odds of producing extreme conditions. 

How We Know It Was Climate Change, Opinion by Noah S Diffenbach, Sunday Review, New York Times, Dec 29, 2017


Analysis of the Week...

The President Doesn't Care to Understand Global Warming

President Trump raises his hand toward a camera. President Trump departs for holiday travel to his Mar-a-Lago estate on Dec 22

President Trump departs for holiday travel to his Mar-a-Lago estate on Friday, December 22

In the first novel ever written about Sherlock Homes, we learn something peculiar about the London detective. Holmes, supposedly a modern man and a keen expert in the workings of the world, does not know how the solar system works. Specifically he is unfamiliar with the heliocentric Copernican model, which, upon its slow acceptance in the 17th century, revolutionized Western thought about the place of our species in the universe.

“What the deuce is it to me?” Holmes asks his sputtering soon-to-be sidekick, Dr. Watson. “You say that we go ’round the sun. If we went round the moon it would not make a pennyworth of difference to me or to my work.”

Brains are a kind of “little empty attic,” says the detective, and they should be filled only with furniture that’s useful to one’s line of work. Holmes doesn’t doubt the Copernican model; he simply has no use for it in solving murder cases. “Now that I do know it,” he adds, “I shall do my best to forget it.”

Thursday night, as record lows gripped most of the country’s northern half, President Trump clarified that he does not understand another revolution in our knowledge of the natural order of things: the theory of human-driven climate change.

The President Doesn't Care to Understand Global Warming by Robinson Meyer, The Atlantic, Dec 29, 2017 


Toon of the Week...

2017 Toon 52 


Quote of the Week...

I like to think of the Earth’s climate like a heavy train. A train cannot stop quickly; the brakes have to be applied far ahead of an obstacle. The ocean is our “climate train.”

US government climate report looks at how the oceans are buffering climate change by John Abraham, Climate Consensus - the 97%, Guardian, Dec 26, 2017 


Coming Soon on SkS...

  • On its hundredth birthday in 1959, Edward Teller warned the oil industry about global warming' (Ben Franta)
  • 2017 was the hottest year on record without an El Niño, thanks to global warming (Dana)
  • SkS Year in Review (Baerbel)
  • Guest Post (John Abraham)
  • New research this week (Ari)
  • 2018 SkS Weekly Climate Change & Global Warming News Roundup #1 (John Hartz)
  • 2017 SkS Weekly Climate Change & Global Waming Digest #1 (John Hartz)

Poster of the Week...

 2017 Poster 52


SkS Week in Review... 


97 Hours of Consensus...

97 Hours: John Mitchell 

 

John Mitchell's bio page and Quote source

High resolution JPEG (1024 pixels wide)



from Skeptical Science http://ift.tt/2C175bu

Happy New Year!... Story of the Week... Analysis of the Week... Toon of the Week... Quote of the Week... Coming Soon on SkS... Poster of the Week...  SkS Week in Review... 97 Hours of Consensus...

Happy New Year!

2017 Poster 52 

Happy New Year from the all-volunteer, SkS author team!


Story of the Week...

How We Know It Was Climate Change

Houston Floding_Hurricane Harvey Sep 2017 

Flooding south of Houston in September in the wake of Hurricane Harvey. Credit Barbara Davidson for The New York Times

This was a year of devastating weather, including historic hurricanes and wildfires here in the United States. Did climate change play a role? Increasingly, scientists are able to answer that question — and increasingly, the answer is yes.

My lab recently published a new framework for examining connections between global warming and extreme events. Other scientists are doing similar research. How would we go about testing whether global warming has influenced the events that occurred this year?

Consider Hurricane Harvey, which caused enormous destruction along the Gulf Coast; it will cost an estimated $180 billion to recover from the hurricane’s storm surge, high winds and record-setting precipitation and flooding. Did global warming contribute to this disaster?

The word “contribute” is key. This doesn’t mean that without global warming, there wouldn’t have been a hurricane. Rather, the question is whether changes in the climate raised the odds of producing extreme conditions. 

How We Know It Was Climate Change, Opinion by Noah S Diffenbach, Sunday Review, New York Times, Dec 29, 2017


Analysis of the Week...

The President Doesn't Care to Understand Global Warming

President Trump raises his hand toward a camera. President Trump departs for holiday travel to his Mar-a-Lago estate on Dec 22

President Trump departs for holiday travel to his Mar-a-Lago estate on Friday, December 22

In the first novel ever written about Sherlock Homes, we learn something peculiar about the London detective. Holmes, supposedly a modern man and a keen expert in the workings of the world, does not know how the solar system works. Specifically he is unfamiliar with the heliocentric Copernican model, which, upon its slow acceptance in the 17th century, revolutionized Western thought about the place of our species in the universe.

“What the deuce is it to me?” Holmes asks his sputtering soon-to-be sidekick, Dr. Watson. “You say that we go ’round the sun. If we went round the moon it would not make a pennyworth of difference to me or to my work.”

Brains are a kind of “little empty attic,” says the detective, and they should be filled only with furniture that’s useful to one’s line of work. Holmes doesn’t doubt the Copernican model; he simply has no use for it in solving murder cases. “Now that I do know it,” he adds, “I shall do my best to forget it.”

Thursday night, as record lows gripped most of the country’s northern half, President Trump clarified that he does not understand another revolution in our knowledge of the natural order of things: the theory of human-driven climate change.

The President Doesn't Care to Understand Global Warming by Robinson Meyer, The Atlantic, Dec 29, 2017 


Toon of the Week...

2017 Toon 52 


Quote of the Week...

I like to think of the Earth’s climate like a heavy train. A train cannot stop quickly; the brakes have to be applied far ahead of an obstacle. The ocean is our “climate train.”

US government climate report looks at how the oceans are buffering climate change by John Abraham, Climate Consensus - the 97%, Guardian, Dec 26, 2017 


Coming Soon on SkS...

  • On its hundredth birthday in 1959, Edward Teller warned the oil industry about global warming' (Ben Franta)
  • 2017 was the hottest year on record without an El Niño, thanks to global warming (Dana)
  • SkS Year in Review (Baerbel)
  • Guest Post (John Abraham)
  • New research this week (Ari)
  • 2018 SkS Weekly Climate Change & Global Warming News Roundup #1 (John Hartz)
  • 2017 SkS Weekly Climate Change & Global Waming Digest #1 (John Hartz)

Poster of the Week...

 2017 Poster 52


SkS Week in Review... 


97 Hours of Consensus...

97 Hours: John Mitchell 

 

John Mitchell's bio page and Quote source

High resolution JPEG (1024 pixels wide)



from Skeptical Science http://ift.tt/2C175bu

Does a supermoon have a super effect on us?

A merge of two images: moon from Wikimedia Commons and Superman emblem, via layoutsparks.com

EarthSky’s 2018 lunar calendars are here! Get yours while they last.

The term supermoon denotes a new or full moon that occurs at roughly the same time the moon is nearest Earth in its monthly orbit. We’re coming up on the “most super” supermoon of 2018 on January 1 (January 2 for Asia, Australia, New Zealand), which will light up the nighttime from dusk to dawn.

An astrologer, not an astronomer, coined the term supermoon, and it has come into wide usage only recently. It’s an example of modern folklore, largely accepted and spread by a now-global community, via word of mouth and the Internet.

Some might suppose that a supermoon has some kind of effect on people on Earth. But does it? I decided to calculate the values of different influences on individuals at the extreme of lunar perigee, the point at which the moon is closest to Earth and, presumably, has the greatest effect on our planet.

Image courtesy of Jim Fisher.

Astronomers use the term perigee to describe the moon’s closest point to Earth, from Greek words peri meaning “near” and gee meaning “Earth.”

In astronomy and other sciences, a related term – perigean tides – refers to the higher tides that can occur when a new or full moon and the month’s perigee coincide, as they fairly frequently do. Simply put, an extra-close new or full moon causes higher-than-usual perigean tides.

What’s more, given the change in distance between the moon’s farthest and closest points, the full moon can appear as much as 14% larger in the sky and 30% brighter to our eyes than at minimum size and brightness.

These changes do not come all of a sudden from month to month, however, and without anything with which to compare them, the changes in the moon’s size or brightness are hard to quantify by simple observation. To notice the difference, you would need to see the apogean (smallest) full moon and the perigean (largest) full moon side by side. For most of us, that’s only possible through photography or through some form of direct measurement, although careful observers have claimed to be able to discern a supermoon’s extra large size with the eye.

During the time of a supermoon – or any new or full moon – our satellite is in line with the sun. At that time, the sun and moon’s gravitational effects combine. For reasons we won’t discuss here, the sun’s gravitational effect on Earth (as in influencing the tides) is only about half that of the moon. For this discussion, we will simply ignore the sun’s influence.

When the moon is closest to the Earth, its gravitational pull is at its peak.

So the question becomes, how much does the moon’s gravitational influence on Earth vary from minimum (apogee, or farthest point from the planet) to maximum (perigee)?

I won’t bore you (or scare you!) with the math, but the variation from minimum lunar pull to maximum pull is roughly 23 percent. That sounds like a lot. However, it amounts to  less than 2 ten-thousandths of the mass (or less precisely, the “weight”) of the moon.

Join the Virtual Telescope Project in Rome for an online viewing of the January 1, 2018 supermoon.

More importantly from an astrological perspective (I presume, since I decidedly am not an astrologer) would be the effect on a human being. Consider an 80-kilogram (176-pound) human being. The maximum difference between apogean and perigean moons is about 73 milligrams, or about 1/14th the mass of an ordinary paper clip.

If you factor in the solar gravity effect for a supermoon, or full moon closest to Earth, this effect may rise to about 110 milligrams, roughly equivalent to about 1/9th the mass of a paperclip.

In either case, the effects are imperceptible, and far smaller than those encountered in other everyday situations, such as being near a mountain or even a large building.

But, you might counter, I said earlier than an extra-close full moon causes higher-than-usual perigean tides. The tides are a very different situation from human beings. Tides work through what is called a differential gravitational effect. Specifically, the force of gravity exerted on the part of the Earth opposite the moon (the far side of Earth, as seen from the moon) is slightly less than the force of gravity exerted on the part of the Earth directly beneath the moon (the Earth’s near side, as seen from the moon) at any given time. Why? Because there’s an additional distance – about 8,000 miles – from one side of Earth to the other. The force of gravity weakens rapidly with increasing distance, producing the differential.

The result of this differential gravitational effect of the moon is that our planet is stretched slightly, along a line between the Earth and moon. The body of the Earth is fairly rigid, so it does not stretch much, but the oceans are much more easily moved. Thus the effect piles up water on either side of Earth, and these piles of water – created by the differential gravitational effect – are the tides. Note that, on average, the tidal effect is quite small. It raises tides only a few feet across an 8,000-mile-wide planet Earth.

Technically, the same effect acts on your body as well, since one side is farther from the moon than the other. However, the difference in distance is on the order of one foot, rather than thousands of miles. Thus the differential is millions of times less, and the effect on a human body infinitesimally small and irrelevant.

Supermoons are important because they focus attention on the moon, and nature in general. But the bottom line is that any physical effects of supermoons are not exactly super. There is no reasonable evidence that they cause super disasters. The effects that people may attribute to them are psychological rather than physical.

There are several supermoons this year and every year. To learn about supermoons in general try this EarthSky post: What is a supermoon?

Enjoying EarthSky? Sign up for our free daily newsletter today!

Will Saunders caught the moonset – at nearly the crest of the moon’s full phase – from Monument Valley, on the Utah-Arizona border.

Bottom line: Sure, the moon (and sun) creates the tides. And an extra close moon can create higher-than-usual tides. But this doesn’t mean that an extra close new or full moon – a supermoon – has an effect on human beings. In fact, the effects of a supermoon are imperceptible, and far smaller than those encountered in other everyday situations, such as being near a mountain or even a large building.



from EarthSky http://ift.tt/12HZwhf

A merge of two images: moon from Wikimedia Commons and Superman emblem, via layoutsparks.com

EarthSky’s 2018 lunar calendars are here! Get yours while they last.

The term supermoon denotes a new or full moon that occurs at roughly the same time the moon is nearest Earth in its monthly orbit. We’re coming up on the “most super” supermoon of 2018 on January 1 (January 2 for Asia, Australia, New Zealand), which will light up the nighttime from dusk to dawn.

An astrologer, not an astronomer, coined the term supermoon, and it has come into wide usage only recently. It’s an example of modern folklore, largely accepted and spread by a now-global community, via word of mouth and the Internet.

Some might suppose that a supermoon has some kind of effect on people on Earth. But does it? I decided to calculate the values of different influences on individuals at the extreme of lunar perigee, the point at which the moon is closest to Earth and, presumably, has the greatest effect on our planet.

Image courtesy of Jim Fisher.

Astronomers use the term perigee to describe the moon’s closest point to Earth, from Greek words peri meaning “near” and gee meaning “Earth.”

In astronomy and other sciences, a related term – perigean tides – refers to the higher tides that can occur when a new or full moon and the month’s perigee coincide, as they fairly frequently do. Simply put, an extra-close new or full moon causes higher-than-usual perigean tides.

What’s more, given the change in distance between the moon’s farthest and closest points, the full moon can appear as much as 14% larger in the sky and 30% brighter to our eyes than at minimum size and brightness.

These changes do not come all of a sudden from month to month, however, and without anything with which to compare them, the changes in the moon’s size or brightness are hard to quantify by simple observation. To notice the difference, you would need to see the apogean (smallest) full moon and the perigean (largest) full moon side by side. For most of us, that’s only possible through photography or through some form of direct measurement, although careful observers have claimed to be able to discern a supermoon’s extra large size with the eye.

During the time of a supermoon – or any new or full moon – our satellite is in line with the sun. At that time, the sun and moon’s gravitational effects combine. For reasons we won’t discuss here, the sun’s gravitational effect on Earth (as in influencing the tides) is only about half that of the moon. For this discussion, we will simply ignore the sun’s influence.

When the moon is closest to the Earth, its gravitational pull is at its peak.

So the question becomes, how much does the moon’s gravitational influence on Earth vary from minimum (apogee, or farthest point from the planet) to maximum (perigee)?

I won’t bore you (or scare you!) with the math, but the variation from minimum lunar pull to maximum pull is roughly 23 percent. That sounds like a lot. However, it amounts to  less than 2 ten-thousandths of the mass (or less precisely, the “weight”) of the moon.

Join the Virtual Telescope Project in Rome for an online viewing of the January 1, 2018 supermoon.

More importantly from an astrological perspective (I presume, since I decidedly am not an astrologer) would be the effect on a human being. Consider an 80-kilogram (176-pound) human being. The maximum difference between apogean and perigean moons is about 73 milligrams, or about 1/14th the mass of an ordinary paper clip.

If you factor in the solar gravity effect for a supermoon, or full moon closest to Earth, this effect may rise to about 110 milligrams, roughly equivalent to about 1/9th the mass of a paperclip.

In either case, the effects are imperceptible, and far smaller than those encountered in other everyday situations, such as being near a mountain or even a large building.

But, you might counter, I said earlier than an extra-close full moon causes higher-than-usual perigean tides. The tides are a very different situation from human beings. Tides work through what is called a differential gravitational effect. Specifically, the force of gravity exerted on the part of the Earth opposite the moon (the far side of Earth, as seen from the moon) is slightly less than the force of gravity exerted on the part of the Earth directly beneath the moon (the Earth’s near side, as seen from the moon) at any given time. Why? Because there’s an additional distance – about 8,000 miles – from one side of Earth to the other. The force of gravity weakens rapidly with increasing distance, producing the differential.

The result of this differential gravitational effect of the moon is that our planet is stretched slightly, along a line between the Earth and moon. The body of the Earth is fairly rigid, so it does not stretch much, but the oceans are much more easily moved. Thus the effect piles up water on either side of Earth, and these piles of water – created by the differential gravitational effect – are the tides. Note that, on average, the tidal effect is quite small. It raises tides only a few feet across an 8,000-mile-wide planet Earth.

Technically, the same effect acts on your body as well, since one side is farther from the moon than the other. However, the difference in distance is on the order of one foot, rather than thousands of miles. Thus the differential is millions of times less, and the effect on a human body infinitesimally small and irrelevant.

Supermoons are important because they focus attention on the moon, and nature in general. But the bottom line is that any physical effects of supermoons are not exactly super. There is no reasonable evidence that they cause super disasters. The effects that people may attribute to them are psychological rather than physical.

There are several supermoons this year and every year. To learn about supermoons in general try this EarthSky post: What is a supermoon?

Enjoying EarthSky? Sign up for our free daily newsletter today!

Will Saunders caught the moonset – at nearly the crest of the moon’s full phase – from Monument Valley, on the Utah-Arizona border.

Bottom line: Sure, the moon (and sun) creates the tides. And an extra close moon can create higher-than-usual tides. But this doesn’t mean that an extra close new or full moon – a supermoon – has an effect on human beings. In fact, the effects of a supermoon are imperceptible, and far smaller than those encountered in other everyday situations, such as being near a mountain or even a large building.



from EarthSky http://ift.tt/12HZwhf

Full moon obscures Quadrantid meteor shower

View larger. | In 2014, as the Quadrantids were flying, those at far northern latitudes were seeing auroras. Photo by Tommy Eliassen.

The Quadrantid meteor shower is 2018’s first major meteor shower. The unfortunate news is that, in 2018, the closest and largest full moon of the year nearly coincides with the peak of this annual meteor shower. Although the Quadrantids have been known to produce some 50-100 meteors in a dark sky, their peak is extremely narrow. Peaks of the Perseid or Geminid meteor showers persist for a day or more, allowing all time zones around the world to enjoy a good display of Perseids and Geminids. But the Quadrantids’ peak lasts only a few hours. So you have to be on the right part of Earth – preferably with the radiant high in your sky – in order to experience the peak of the Quadrantids. What’s more, the shower favors the Northern Hemisphere because its radiant point is so far north on the sky’s dome. Follow the links below to learn more about the Quadrantids in 2018.

Peak dates for the Quadrantid shower in 2018

Where is the Quadrantids’ radiant point?

The Quadrantids are named for a constellation that no longer exists.

Quadrantid meteors have a mysterious parent object.

Barry Simmons in Lake Martin, Alabama captured this Quadrantid meteor on the morning of January 3, 2014. Thank you, Barry.

Barry Simmons in Lake Martin, Alabama captured this Quadrantid meteor on the morning of January 3, 2014. Thank you, Barry.

Peak dates for the Quadrantid shower in 2018 In 2018, the Observer’s Handbook 2018 published by the Royal Astronomical Society in Canada gives the peak as January 3 at 21 hours UTC. The International Meteor Organization seems to be in close agreement, listing 22 hours UTC as the peak. Keep in mind the prediction of the Quadrantid peak represents an educated guess, not an ironclad guarantee. So you see … this shower is a gamble!

If that prediction of the peak holds true, the northeastern part of North America could have a good shot at viewing the shower on the morning of January 3 – if not for the almost-full waning gibbous moon. If you’re game, try your luck in the predawn hours on Janaury 3 and 4.

From mid-northern latitudes, the radiant point for the Quadrantid shower doesn’t climb over the horizon until after midnight.

Where is the Quadrantids’ radiant point? All other things being equal, for any meteor shower, you are likely to see the most meteors when the radiant is high in the sky. In the case of the Quadrantid shower, the radiant point is seen highest in the sky in the dark hour before dawn.

The radiant point of the Quadrantid shower makes an approximate right angle with the Big Dipper and the bright star Arcturus. If you trace the paths of the Quadrantid meteors backward, they appear to radiate from this point on the starry sky.

Now for our usual caveat. You don’t need to find the meteor shower radiant to see the Quadrantid meteors.

You just have to be at mid-northern or far-northern latitudes, up in the wee hours of the morning and hope the peak comes at just the right time to your part of the world. The meteors will radiate from the northern sky, but appear in all parts of the sky.

The now-defunct constellation Quadrans Muralis, for which the Quadrantids are named. Image via Atlas Coelestis.

The Quadrantids are named for a constellation that no longer exists. Most meteor showers are named for the constellations from which they appear to radiate. So it is with the Quadrantids. But the Quadrantids’ constellation no longer exists, except in memory. The name Quadrantids comes from the constellation Quadrans Muralis (Mural Quadrant), created by the French astronomer Jerome Lalande in 1795. This now-obsolete constellation was located between the constellations of Bootes the Herdsman and Draco the Dragon. Where did it go?

To understand the history of the Quadrantids’ name, we have to go back to the earliest observations of this shower. In early January 1825, Antonio Brucalassi in Italy reported that:

… the atmosphere was traversed by a multitude of the luminous bodies known by the name of falling stars.

They appeared to radiate from Quadrans Muralis. In 1839, Adolphe Quetelet of Brussels Observatory in Belgium and Edward C. Herrick in Connecticut independently made the suggestion that the Quadrantids are an annual shower.

But, in 1922, the International Astronomical Union devised a list 88 modern constellations. The list was agreed upon by the International Astronomical Union at its inaugural General Assembly held in Rome in May 1922. It did not include a constellation Quadrans Muralis.

Today, this meteor shower retains the name Quadrantids, for the original and now obsolete constellation Quadrans Muralis.

The radiant point for the Quadrantids is now considered to be at the northern tip of Bootes, near the Big Dipper asterism in our sky, not far from Bootes’ brightest star Arcturus. It is very far north on the sky’s dome, which is why Southern Hemisphere observers probably won’t see many (if any) Quadrantid meteors. Most of the meteors simply won’t make it above the horizon for Southern Hemisphere skywatchers. But some might!

In 2003, Peter Jenniskens proposed that this object, 2003 EH1, is the parent body of the Quadrantid meteor shower.

Quadrantid meteors have a mysterious parent object. In 2003, astronomer Peter Jenniskens tentatively identified the parent body of the Quadrantids as the asteroid 2003 EH1. If indeed this body is the Quadrantids parent, then the Quadrantids, like the Geminid meteors, come from a rocky body – not an icy comet. Strange.

In turn, though, 2003 EH1 might be the same object as the comet C/1490 Y1, which was observed by Chinese, Japanese and Korean astronomers 500 years ago.

So the exact story behind the Quadrantids’ parent object remains somewhat mysterious.

Bottom line: The first major meteor shower of 2018, and every year, the Quadrantid meteor shower, will probably be at its best in the hours between midnight and dawn January 3. Unfortunately, in 2018, the largest full moon of the year will almost coincide with the peak of this annual shower.

Celebrate 2018 with an EarthSky moon calendar!



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View larger. | In 2014, as the Quadrantids were flying, those at far northern latitudes were seeing auroras. Photo by Tommy Eliassen.

The Quadrantid meteor shower is 2018’s first major meteor shower. The unfortunate news is that, in 2018, the closest and largest full moon of the year nearly coincides with the peak of this annual meteor shower. Although the Quadrantids have been known to produce some 50-100 meteors in a dark sky, their peak is extremely narrow. Peaks of the Perseid or Geminid meteor showers persist for a day or more, allowing all time zones around the world to enjoy a good display of Perseids and Geminids. But the Quadrantids’ peak lasts only a few hours. So you have to be on the right part of Earth – preferably with the radiant high in your sky – in order to experience the peak of the Quadrantids. What’s more, the shower favors the Northern Hemisphere because its radiant point is so far north on the sky’s dome. Follow the links below to learn more about the Quadrantids in 2018.

Peak dates for the Quadrantid shower in 2018

Where is the Quadrantids’ radiant point?

The Quadrantids are named for a constellation that no longer exists.

Quadrantid meteors have a mysterious parent object.

Barry Simmons in Lake Martin, Alabama captured this Quadrantid meteor on the morning of January 3, 2014. Thank you, Barry.

Barry Simmons in Lake Martin, Alabama captured this Quadrantid meteor on the morning of January 3, 2014. Thank you, Barry.

Peak dates for the Quadrantid shower in 2018 In 2018, the Observer’s Handbook 2018 published by the Royal Astronomical Society in Canada gives the peak as January 3 at 21 hours UTC. The International Meteor Organization seems to be in close agreement, listing 22 hours UTC as the peak. Keep in mind the prediction of the Quadrantid peak represents an educated guess, not an ironclad guarantee. So you see … this shower is a gamble!

If that prediction of the peak holds true, the northeastern part of North America could have a good shot at viewing the shower on the morning of January 3 – if not for the almost-full waning gibbous moon. If you’re game, try your luck in the predawn hours on Janaury 3 and 4.

From mid-northern latitudes, the radiant point for the Quadrantid shower doesn’t climb over the horizon until after midnight.

Where is the Quadrantids’ radiant point? All other things being equal, for any meteor shower, you are likely to see the most meteors when the radiant is high in the sky. In the case of the Quadrantid shower, the radiant point is seen highest in the sky in the dark hour before dawn.

The radiant point of the Quadrantid shower makes an approximate right angle with the Big Dipper and the bright star Arcturus. If you trace the paths of the Quadrantid meteors backward, they appear to radiate from this point on the starry sky.

Now for our usual caveat. You don’t need to find the meteor shower radiant to see the Quadrantid meteors.

You just have to be at mid-northern or far-northern latitudes, up in the wee hours of the morning and hope the peak comes at just the right time to your part of the world. The meteors will radiate from the northern sky, but appear in all parts of the sky.

The now-defunct constellation Quadrans Muralis, for which the Quadrantids are named. Image via Atlas Coelestis.

The Quadrantids are named for a constellation that no longer exists. Most meteor showers are named for the constellations from which they appear to radiate. So it is with the Quadrantids. But the Quadrantids’ constellation no longer exists, except in memory. The name Quadrantids comes from the constellation Quadrans Muralis (Mural Quadrant), created by the French astronomer Jerome Lalande in 1795. This now-obsolete constellation was located between the constellations of Bootes the Herdsman and Draco the Dragon. Where did it go?

To understand the history of the Quadrantids’ name, we have to go back to the earliest observations of this shower. In early January 1825, Antonio Brucalassi in Italy reported that:

… the atmosphere was traversed by a multitude of the luminous bodies known by the name of falling stars.

They appeared to radiate from Quadrans Muralis. In 1839, Adolphe Quetelet of Brussels Observatory in Belgium and Edward C. Herrick in Connecticut independently made the suggestion that the Quadrantids are an annual shower.

But, in 1922, the International Astronomical Union devised a list 88 modern constellations. The list was agreed upon by the International Astronomical Union at its inaugural General Assembly held in Rome in May 1922. It did not include a constellation Quadrans Muralis.

Today, this meteor shower retains the name Quadrantids, for the original and now obsolete constellation Quadrans Muralis.

The radiant point for the Quadrantids is now considered to be at the northern tip of Bootes, near the Big Dipper asterism in our sky, not far from Bootes’ brightest star Arcturus. It is very far north on the sky’s dome, which is why Southern Hemisphere observers probably won’t see many (if any) Quadrantid meteors. Most of the meteors simply won’t make it above the horizon for Southern Hemisphere skywatchers. But some might!

In 2003, Peter Jenniskens proposed that this object, 2003 EH1, is the parent body of the Quadrantid meteor shower.

Quadrantid meteors have a mysterious parent object. In 2003, astronomer Peter Jenniskens tentatively identified the parent body of the Quadrantids as the asteroid 2003 EH1. If indeed this body is the Quadrantids parent, then the Quadrantids, like the Geminid meteors, come from a rocky body – not an icy comet. Strange.

In turn, though, 2003 EH1 might be the same object as the comet C/1490 Y1, which was observed by Chinese, Japanese and Korean astronomers 500 years ago.

So the exact story behind the Quadrantids’ parent object remains somewhat mysterious.

Bottom line: The first major meteor shower of 2018, and every year, the Quadrantid meteor shower, will probably be at its best in the hours between midnight and dawn January 3. Unfortunately, in 2018, the largest full moon of the year will almost coincide with the peak of this annual shower.

Celebrate 2018 with an EarthSky moon calendar!



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Brightest star Sirius’ midnight culmination on New Years Eve

Tonight – New Year’s Eve – look up for the brightest star in the sky, Sirius, in the constellation Canis Major. This star is up in the evening every year at this time, and – from all parts of Earth (except those far-southern realms in continuous daylight now) – Sirius is easy to identify. December 31 is a special night, the end of a calendar year. And it’s a special night for Sirius, too. This star’s official midnight culmination – when it’s highest in the sky at midnight – comes only once every year. And tonight’s the night.

From the Northern Hemisphere … look toward the south, and you’ll easily notice Sirius shining there at around midnight. From the Southern Hemisphere … look overhead or high in the north at around midnight.

And, by the way, by midnight, we mean the middle of the night, midway between sunset and sunrise.

This star is so bright that you might notice it twinkling fiercely, especially from northerly latitudes, where the star stays closer to the horizon. You might even see it flashing hints of different colors. When you see Sirius high in the sky, as you will from Earth’s Southern Hemisphere, it’ll shine with a bright, steady white light.

Remember … the midnight culmination of Sirius by the clock might be off by as much as one-half hour or so, depending on how far east or west you live from the meridian that governs your time zone.

Click here for transit (midnight culmination) times for Sirius in your sky

Even from big cities, you can see Sirius, the sky’s brightest star. Gowrishankar Lakshminarayanan created this composite image on December 26, 2017 and wrote: “After a series of clouded night skies in New York City, we finally got a clear night though it was bitter cold and the temperature dropped to 25 F.! Here you can see the brightest star of the winter night sky – Sirius – and its path as it rises in the southeast sky to clip the spire of the Freedom Tower. This is a 78-image composite, spaced 30 seconds apart. I always thought that star trails within light-polluted city skies weren’t a good idea, since we hardly see any stars. However, thanks to bright stars like Sirius, we can still show a nice star trail in NYC!”

Bottom line: If you’re celebrating the New Year, and you happen to gaze up at the sky, look for Sirius. This star’s midnight culmination – when it’s highest in the sky at midnight – comes on New Year’s Eve.

Donate: Your support means the world to us



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Tonight – New Year’s Eve – look up for the brightest star in the sky, Sirius, in the constellation Canis Major. This star is up in the evening every year at this time, and – from all parts of Earth (except those far-southern realms in continuous daylight now) – Sirius is easy to identify. December 31 is a special night, the end of a calendar year. And it’s a special night for Sirius, too. This star’s official midnight culmination – when it’s highest in the sky at midnight – comes only once every year. And tonight’s the night.

From the Northern Hemisphere … look toward the south, and you’ll easily notice Sirius shining there at around midnight. From the Southern Hemisphere … look overhead or high in the north at around midnight.

And, by the way, by midnight, we mean the middle of the night, midway between sunset and sunrise.

This star is so bright that you might notice it twinkling fiercely, especially from northerly latitudes, where the star stays closer to the horizon. You might even see it flashing hints of different colors. When you see Sirius high in the sky, as you will from Earth’s Southern Hemisphere, it’ll shine with a bright, steady white light.

Remember … the midnight culmination of Sirius by the clock might be off by as much as one-half hour or so, depending on how far east or west you live from the meridian that governs your time zone.

Click here for transit (midnight culmination) times for Sirius in your sky

Even from big cities, you can see Sirius, the sky’s brightest star. Gowrishankar Lakshminarayanan created this composite image on December 26, 2017 and wrote: “After a series of clouded night skies in New York City, we finally got a clear night though it was bitter cold and the temperature dropped to 25 F.! Here you can see the brightest star of the winter night sky – Sirius – and its path as it rises in the southeast sky to clip the spire of the Freedom Tower. This is a 78-image composite, spaced 30 seconds apart. I always thought that star trails within light-polluted city skies weren’t a good idea, since we hardly see any stars. However, thanks to bright stars like Sirius, we can still show a nice star trail in NYC!”

Bottom line: If you’re celebrating the New Year, and you happen to gaze up at the sky, look for Sirius. This star’s midnight culmination – when it’s highest in the sky at midnight – comes on New Year’s Eve.

Donate: Your support means the world to us



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2017 SkS Weekly Climate Change & Global Warming News Roundup #52

A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week. 

Editor's Pick

Vive la résistance: 10 ways people stood up for the planet in 2017

Vive la resistance 

Grist / Justin Sullivan / Staff / Getty Images

One year ago, we wondered what would happen after a man who called climate change a Chinese hoax was elected president of the United States.

Certainly, 2017 will be remembered for a series of cringe-worthy political appointments, disappointing regulatory repeals, and controversial executive actions — not to mention Trump’s decision to exit the Paris Agreement. But it was also a year that birthed a new band of scrappy resisters who fought the climate-change denying, regulation-repealing powers that be.

As a result, 2017 was actually a pretty impressive year for resistance — and here are some of the efforts that led that charge: 

Vive la résistance: 10 ways people stood up for the planet in 2017 by Justine Calma, Grist, Dec 27, 2017


Links posted on Facebook

Sun Dec 24, 2017

Mon Dec 25, 2017

Tue Dec 26, 2017

Wed Dec 27, 2017

Thu Dec 28, 2017

Fri Dec 29, 2017

Sat Dec 30, 2017



from Skeptical Science http://ift.tt/2Eixkfb
A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week. 

Editor's Pick

Vive la résistance: 10 ways people stood up for the planet in 2017

Vive la resistance 

Grist / Justin Sullivan / Staff / Getty Images

One year ago, we wondered what would happen after a man who called climate change a Chinese hoax was elected president of the United States.

Certainly, 2017 will be remembered for a series of cringe-worthy political appointments, disappointing regulatory repeals, and controversial executive actions — not to mention Trump’s decision to exit the Paris Agreement. But it was also a year that birthed a new band of scrappy resisters who fought the climate-change denying, regulation-repealing powers that be.

As a result, 2017 was actually a pretty impressive year for resistance — and here are some of the efforts that led that charge: 

Vive la résistance: 10 ways people stood up for the planet in 2017 by Justine Calma, Grist, Dec 27, 2017


Links posted on Facebook

Sun Dec 24, 2017

Mon Dec 25, 2017

Tue Dec 26, 2017

Wed Dec 27, 2017

Thu Dec 28, 2017

Fri Dec 29, 2017

Sat Dec 30, 2017



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Top 7 EarthSky galleries of 2017

Here are the most popular photo galleries from 2017:

Moon sweeps past Venus and Mars. As 2017 opened, the young moon swept past dazzling Venus in the west after sunset. Mars was there, too, and, for those with optical aid, Neptune! Go to gallery.

As seen from the Northern Hemisphere, the moon, Venus and Mars arced up and to the left of the sunset Sunday evening, January 1, 2017. Photo by Gowrishankar Lakshminarayanan Parsippany, New Jersey. More photos here.

February 10-11 lunar eclipse. A penumbral eclipse is subtle, but has a quiet beauty all its own. Go to gallery.

February 10, 2017 full moon rising over northeast Oklahoma, with a tinge of Earth’s penumbral shadow visible. Photo by Mike O’Neal. More photos.

Moon and Jupiter. Wonderful photos of the moon and Jupiter on June 3, 2017, from around the world. Go to gallery.

Moon and Jupiter on June 3, 2017 from Deirdre Horan in Dublin, Ireland. More photos.

Summer full moon. EarthSky friends are moon-lovers! Favorite photos of the July 2017 full moon from EarthSky friends around the world. Go to gallery.

John Ashley at Glacier National Park, Montana, wrote: “The July 2017 full moon rises over Mount Saint Nicholas on its way into a warm summer dusk. Video on my FB page at JohnAshleyFineArt. More photos. ”

Total solar eclipse. We received many more wonderful photos of the August 21 eclipse than for any prior event. Go to gallery.

Sue Waddell contributed this eclipse composite from Eastview, Kentucky, where there was a 98.3% eclipse. More photos.

Orionid meteor shower. October’s Orionid meteor shower didn’t disappoint. Go to gallery.

Composite image of meteors seen on the morning of October 21, 2017 from Simon Lee Waldram of Fuerteshoot in Spain. More photos.

A grand year for the Geminids. December’s Geminid meteor shower was thought to have a better-than-average chance of producing a rich display, since the Geminids’ parent body – a strange rock-comet called 3200 Phaethon – is nearby. And so it was! Go to gallery.

“The Geminids are good,” reported veteran meteor observer Eliot Herman in Tucson, Arizona, who captured this fireball on the morning of December 14 around 4 a.m. More photos.

Bottom line: Favorite Earthsky photo galleries of 2017.



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Here are the most popular photo galleries from 2017:

Moon sweeps past Venus and Mars. As 2017 opened, the young moon swept past dazzling Venus in the west after sunset. Mars was there, too, and, for those with optical aid, Neptune! Go to gallery.

As seen from the Northern Hemisphere, the moon, Venus and Mars arced up and to the left of the sunset Sunday evening, January 1, 2017. Photo by Gowrishankar Lakshminarayanan Parsippany, New Jersey. More photos here.

February 10-11 lunar eclipse. A penumbral eclipse is subtle, but has a quiet beauty all its own. Go to gallery.

February 10, 2017 full moon rising over northeast Oklahoma, with a tinge of Earth’s penumbral shadow visible. Photo by Mike O’Neal. More photos.

Moon and Jupiter. Wonderful photos of the moon and Jupiter on June 3, 2017, from around the world. Go to gallery.

Moon and Jupiter on June 3, 2017 from Deirdre Horan in Dublin, Ireland. More photos.

Summer full moon. EarthSky friends are moon-lovers! Favorite photos of the July 2017 full moon from EarthSky friends around the world. Go to gallery.

John Ashley at Glacier National Park, Montana, wrote: “The July 2017 full moon rises over Mount Saint Nicholas on its way into a warm summer dusk. Video on my FB page at JohnAshleyFineArt. More photos. ”

Total solar eclipse. We received many more wonderful photos of the August 21 eclipse than for any prior event. Go to gallery.

Sue Waddell contributed this eclipse composite from Eastview, Kentucky, where there was a 98.3% eclipse. More photos.

Orionid meteor shower. October’s Orionid meteor shower didn’t disappoint. Go to gallery.

Composite image of meteors seen on the morning of October 21, 2017 from Simon Lee Waldram of Fuerteshoot in Spain. More photos.

A grand year for the Geminids. December’s Geminid meteor shower was thought to have a better-than-average chance of producing a rich display, since the Geminids’ parent body – a strange rock-comet called 3200 Phaethon – is nearby. And so it was! Go to gallery.

“The Geminids are good,” reported veteran meteor observer Eliot Herman in Tucson, Arizona, who captured this fireball on the morning of December 14 around 4 a.m. More photos.

Bottom line: Favorite Earthsky photo galleries of 2017.



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