Moon in Winter Circle on April 2

Our annual fund-raiser is here! Help EarthSky stay an independent voice.

Tonight – April 2, 2017 – look for the moon and Winter Circle (or Winter Hexagon) stars. It’s difficult to convey the humongous size of the Circle, a great lasso of brilliant stars that fills our western sky at dusk and nightfall. It can be seen from around the world, although its orientation with respect to the horizon will be different, depending on where you are.

No matter what part of Earth you’re standing on, though, look for a circular (or hexagonal) pattern of bright stars around the April 2 moon. Just be sure to look at nightfall, because the Winter Circle stars will sink below the horizon by early evening.

And, if you’re in the Southern Hemisphere, notice the sky’s brightest star – Sirius – will appear at the top of the Circle and the star Capella at the bottom (if you can see Capella at all; it’s far to the north on the sky’s dome).

Help EarthSky stay an independent voice! Donate here.

The Winter Circle in April is found over the western horizon as soon as darkness falls. The green line depicts the ecliptic – the sun’s apparent yearly path in front of the constellations of the Zodiac. Aldebaran is the brightest star in the zodiacal constellation Taurus the Bull, while Pollux and Castor are the two brightest stars in the constellation Gemini the Twins

Even after the moon moves away, you can find the Winter Circle in April over your western horizon as soon as darkness falls. The green line depicts the ecliptic – or path of the sun, moon and planets on our sky’s dome. See the 3 stars of Orion’s Belt? It can help you locate the rest of the Circle.

The orientation of stars with respect to the horizon – and their height above the horizon – is different as seen from different parts of the globe. Here’s a gorgeous shot from March 30, 2017 of Orion and Canis Major – containing the sky’s brightest star Sirius – as captured from the Philippines on March 30, 2017. Photo by Gabriel Obusan.

The Winter Circle stars are bright, but the brightest starlike object in the sky on these April 2017 evenings is the planet Jupiter. At nightfall on April 2, the moon and Winter Circle are in the west, while Jupiter shines in the opposite direction – east – and quite close the horizon after sunset. Earth is about to go between Jupiter and the sun, and so the planet is nearly at its brightest for this year. Jupiter’s yearly opposition will come on April 7.

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

In any year, you can follow an imaginary arc in the handle of the Big Dipper to the bright stars Arcturus and Spica. This year, 2017, is extra special because the dazzling planet Jupiter beams close to Spica all year long.

Here’s another way to find Jupiter, via the very noticeable, small, square-ish constellation Corvus the Crow.

Bottom line: Use the moon on April 2, 2017, to find the bright stars of the Winter Circle!



from EarthSky http://ift.tt/1ql1xBW

Our annual fund-raiser is here! Help EarthSky stay an independent voice.

Tonight – April 2, 2017 – look for the moon and Winter Circle (or Winter Hexagon) stars. It’s difficult to convey the humongous size of the Circle, a great lasso of brilliant stars that fills our western sky at dusk and nightfall. It can be seen from around the world, although its orientation with respect to the horizon will be different, depending on where you are.

No matter what part of Earth you’re standing on, though, look for a circular (or hexagonal) pattern of bright stars around the April 2 moon. Just be sure to look at nightfall, because the Winter Circle stars will sink below the horizon by early evening.

And, if you’re in the Southern Hemisphere, notice the sky’s brightest star – Sirius – will appear at the top of the Circle and the star Capella at the bottom (if you can see Capella at all; it’s far to the north on the sky’s dome).

Help EarthSky stay an independent voice! Donate here.

The Winter Circle in April is found over the western horizon as soon as darkness falls. The green line depicts the ecliptic – the sun’s apparent yearly path in front of the constellations of the Zodiac. Aldebaran is the brightest star in the zodiacal constellation Taurus the Bull, while Pollux and Castor are the two brightest stars in the constellation Gemini the Twins

Even after the moon moves away, you can find the Winter Circle in April over your western horizon as soon as darkness falls. The green line depicts the ecliptic – or path of the sun, moon and planets on our sky’s dome. See the 3 stars of Orion’s Belt? It can help you locate the rest of the Circle.

The orientation of stars with respect to the horizon – and their height above the horizon – is different as seen from different parts of the globe. Here’s a gorgeous shot from March 30, 2017 of Orion and Canis Major – containing the sky’s brightest star Sirius – as captured from the Philippines on March 30, 2017. Photo by Gabriel Obusan.

The Winter Circle stars are bright, but the brightest starlike object in the sky on these April 2017 evenings is the planet Jupiter. At nightfall on April 2, the moon and Winter Circle are in the west, while Jupiter shines in the opposite direction – east – and quite close the horizon after sunset. Earth is about to go between Jupiter and the sun, and so the planet is nearly at its brightest for this year. Jupiter’s yearly opposition will come on April 7.

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

In any year, you can follow an imaginary arc in the handle of the Big Dipper to the bright stars Arcturus and Spica. This year, 2017, is extra special because the dazzling planet Jupiter beams close to Spica all year long.

Here’s another way to find Jupiter, via the very noticeable, small, square-ish constellation Corvus the Crow.

Bottom line: Use the moon on April 2, 2017, to find the bright stars of the Winter Circle!



from EarthSky http://ift.tt/1ql1xBW
Aucun commentaire:
Libellés :

2017 SkS Weekly Climate Change & Global Warming News Roundup #13

A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week. Articles of signifigance as determined by the editor are highlighted in the Editor's Picks' section.

Editor's Picks

One of the most troubling ideas about climate change just found new evidence in its favor

Jet Stream Visualization NASA

Visualization of a very wavy Northern Hemisphere jet stream. (NASA)

Ever since 2012, scientists have been debating a complex and frankly explosive idea about how a warming planet will alter our weather — one that, if it’s correct, would have profound implications across the Northern Hemisphere and especially in its middle latitudes, where hundreds of millions of people live.

The idea is that climate change doesn’t merely increase the overall likelihood of heat waves, say, or the volume of rainfall — it also changes the flow of weather itself. By altering massive planet-scale air patterns like the jet stream (pictured above), which flows in waves from west to east in the Northern Hemisphere, a warming planet causes our weather to become more stuck in place. This means that a given weather pattern, whatever it may be, may persist for longer, thus driving extreme droughts, heat waves, downpours and more.

This basic idea has sparked half a decade of criticism and debate, and at the cutting edge of research, scientists continue to grapple with it. And now, a new study once again reinforces one of its core aspects.

One of the most troubling ideas about climate change just found new evidence in its favor by Chris Mooney, Energy & Environment, Washington Post, Mar 27, 2017 

Thinning Arctic sea ice lets in light, prompts algae bloom-study

Arctic Ocean ICESCAPE Mission June 2012

The crew of the U.S. Coast Guard Cutter Healy, in the midst of their ICESCAPE mission, retrieves supplies for some mid-mission fixes dropped by parachute from a C-130 in the Arctic Ocean in this July 12, 2011 

Climate change is stirring life in the Arctic Ocean as thinning sea ice lets in more sunlight, allowing microscopic algae to bloom in the inhospitable region around the North Pole, scientists said on Wednesday.

The micro-algae may now be able to grow under the ice across almost 30 percent of the Arctic Ocean at the peak of the brief summer in July, up from about five percent 30 years ago, they wrote. Blooms may become even more widespread.

"Recent climate change may have markedly altered the ecology of the Arctic Ocean," wrote scientists in the United States and Britain led by Christopher Horvat of Harvard University.

The first massive under-ice bloom of algae was seen in 2011 in the Chukchi Sea north of the Bering Strait separating Alaska and Russia, a region until then thought too dark for photosynthesis.

Thinning Arctic sea ice lets in light, prompts algae bloom-study by Alister Doyle, Reuters, Mar 30, 2017

‘Critical’ NASA Climate Missions Targeted in Budget Cuts

Atmospheric C02 Concentration

Carbon dioxide concentrations across the globe as measured by the Orbiting Carbon Observatory-2 in May 2016. (Credit: NASA)

In his most recent weekly address, President Trump praised NASA’s “mission of exploration and discovery” and its ability to allow mankind to “look to the heavens with wonder and curiosity.” But left out of his statements was the work NASA does to peer back at our home planet and unravel its many remaining mysteries — a mission targeted for cuts in his administration’s budget outline released earlier this month.

In a budget otherwise scant on specifics, four climate-related NASA satellite missions were proposed for termination, including one already in orbit.

Those missions are aimed not only at helping scientists learn more about key parts of the climate system and how global warming is changing them, but also at practical matters such as monitoring the health of the nation’s coastal waters and providing earlier warnings of drought stress in crops.

‘Critical’ NASA Climate Missions Targeted in Budget Cuts by Andrea Thompson, Climate Central, Mar 31, 2017

Greenland's Coastal Ice Passed a Climate Tipping Point 20 Years Ago, Study Says

Greenland glaciers 

Credit: Uriel Sinai/Getty Images 

Ice caps and glaciers along the coast of Greenland passed a tipping point in 1997, when a layer of snow that once absorbed summer meltwater became fully saturated. Since then, the coastal ice fields—separate from the main Greenland Ice Sheet—have been melting three times faster than they had been, according to a new study published Friday in the journal Nature Communications.

"The melting ice caps are an alarm signal for the ice sheet. It means long-term ice mass loss is inevitable. It will increase and accelerate if nothing changes," said lead author Brice Noël, a scientist at the  University of Utrecht Institute for Marine and Atmospheric Research. "It's very unlikely the ice caps will recover. It's a climate tipping point—the time at which a change or an effect cannot be stopped."

Climate scientists are wary of tipping points, when a series of small changes make a much larger change inevitable. The fear is a total meltdown of the Greenland Ice Sheet, which would raise global sea level by 24 feet, Noël said. Overall, the rate of ice sheet melting is accelerating, according to peer-reviewed studies cited in the most recent Arctic report from NOAA. 

Greenland's Coastal Ice Passed a Climate Tipping Point 20 Years Ago, Study Says by Bob Berwyn, Inside Climate News, Mar 31, 2017

Sun Mar 26

Mon Mar 27

Tue Mar 28

Wed Mar 29

Thu Mar 30

Fri Mar 31

Sat Apr 1



from Skeptical Science http://ift.tt/2nLnPi6

A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week. Articles of signifigance as determined by the editor are highlighted in the Editor's Picks' section.

Editor's Picks

One of the most troubling ideas about climate change just found new evidence in its favor

Jet Stream Visualization NASA

Visualization of a very wavy Northern Hemisphere jet stream. (NASA)

Ever since 2012, scientists have been debating a complex and frankly explosive idea about how a warming planet will alter our weather — one that, if it’s correct, would have profound implications across the Northern Hemisphere and especially in its middle latitudes, where hundreds of millions of people live.

The idea is that climate change doesn’t merely increase the overall likelihood of heat waves, say, or the volume of rainfall — it also changes the flow of weather itself. By altering massive planet-scale air patterns like the jet stream (pictured above), which flows in waves from west to east in the Northern Hemisphere, a warming planet causes our weather to become more stuck in place. This means that a given weather pattern, whatever it may be, may persist for longer, thus driving extreme droughts, heat waves, downpours and more.

This basic idea has sparked half a decade of criticism and debate, and at the cutting edge of research, scientists continue to grapple with it. And now, a new study once again reinforces one of its core aspects.

One of the most troubling ideas about climate change just found new evidence in its favor by Chris Mooney, Energy & Environment, Washington Post, Mar 27, 2017 

Thinning Arctic sea ice lets in light, prompts algae bloom-study

Arctic Ocean ICESCAPE Mission June 2012

The crew of the U.S. Coast Guard Cutter Healy, in the midst of their ICESCAPE mission, retrieves supplies for some mid-mission fixes dropped by parachute from a C-130 in the Arctic Ocean in this July 12, 2011 

Climate change is stirring life in the Arctic Ocean as thinning sea ice lets in more sunlight, allowing microscopic algae to bloom in the inhospitable region around the North Pole, scientists said on Wednesday.

The micro-algae may now be able to grow under the ice across almost 30 percent of the Arctic Ocean at the peak of the brief summer in July, up from about five percent 30 years ago, they wrote. Blooms may become even more widespread.

"Recent climate change may have markedly altered the ecology of the Arctic Ocean," wrote scientists in the United States and Britain led by Christopher Horvat of Harvard University.

The first massive under-ice bloom of algae was seen in 2011 in the Chukchi Sea north of the Bering Strait separating Alaska and Russia, a region until then thought too dark for photosynthesis.

Thinning Arctic sea ice lets in light, prompts algae bloom-study by Alister Doyle, Reuters, Mar 30, 2017

‘Critical’ NASA Climate Missions Targeted in Budget Cuts

Atmospheric C02 Concentration

Carbon dioxide concentrations across the globe as measured by the Orbiting Carbon Observatory-2 in May 2016. (Credit: NASA)

In his most recent weekly address, President Trump praised NASA’s “mission of exploration and discovery” and its ability to allow mankind to “look to the heavens with wonder and curiosity.” But left out of his statements was the work NASA does to peer back at our home planet and unravel its many remaining mysteries — a mission targeted for cuts in his administration’s budget outline released earlier this month.

In a budget otherwise scant on specifics, four climate-related NASA satellite missions were proposed for termination, including one already in orbit.

Those missions are aimed not only at helping scientists learn more about key parts of the climate system and how global warming is changing them, but also at practical matters such as monitoring the health of the nation’s coastal waters and providing earlier warnings of drought stress in crops.

‘Critical’ NASA Climate Missions Targeted in Budget Cuts by Andrea Thompson, Climate Central, Mar 31, 2017

Greenland's Coastal Ice Passed a Climate Tipping Point 20 Years Ago, Study Says

Greenland glaciers 

Credit: Uriel Sinai/Getty Images 

Ice caps and glaciers along the coast of Greenland passed a tipping point in 1997, when a layer of snow that once absorbed summer meltwater became fully saturated. Since then, the coastal ice fields—separate from the main Greenland Ice Sheet—have been melting three times faster than they had been, according to a new study published Friday in the journal Nature Communications.

"The melting ice caps are an alarm signal for the ice sheet. It means long-term ice mass loss is inevitable. It will increase and accelerate if nothing changes," said lead author Brice Noël, a scientist at the  University of Utrecht Institute for Marine and Atmospheric Research. "It's very unlikely the ice caps will recover. It's a climate tipping point—the time at which a change or an effect cannot be stopped."

Climate scientists are wary of tipping points, when a series of small changes make a much larger change inevitable. The fear is a total meltdown of the Greenland Ice Sheet, which would raise global sea level by 24 feet, Noël said. Overall, the rate of ice sheet melting is accelerating, according to peer-reviewed studies cited in the most recent Arctic report from NOAA. 

Greenland's Coastal Ice Passed a Climate Tipping Point 20 Years Ago, Study Says by Bob Berwyn, Inside Climate News, Mar 31, 2017

Sun Mar 26

Mon Mar 27

Tue Mar 28

Wed Mar 29

Thu Mar 30

Fri Mar 31

Sat Apr 1



from Skeptical Science http://ift.tt/2nLnPi6
Aucun commentaire:
Libellés : ,

Ask Ethan: What’s the difference between a fermion and a boson? (Synopsis) [Starts With A Bang]

“The layman always means, when he says “reality” that he is speaking of something self-evidently known; whereas to me it seems the most important and exceedingly difficult task of our time is to work on the construction of a new idea of reality.” -Wolfgang Pauli

On the surface, it shouldn’t appear to make all that much difference to the Universe whether a particle has a spin in half-integer intervals (±1/2, ±3/2, ±5/2) or in integer intervals (0, ±1, ±2). The former is what defines fermions, while the latter defines bosons. This hardly seems like an important distinction, since intrinsic angular momentum is such a nebulous property to our intuitions, unlike, say, mass or electric charge.

The known particles in the Standard Model. These are all the fundamental particles that have been directly discovered; the graviton, although undiscovered, would be a spin=2 boson. Image credit: E. Siegel.

The known particles in the Standard Model. These are all the fundamental particles that have been directly discovered; the graviton, although undiscovered, would be a spin=2 boson. Image credit: E. Siegel.

Yet this simple, minor difference carries with it two incredible consequences: one for the existence of distinct particles for antimatter and one for the Pauli exclusion principle, that are required for matter as we know it to be. Without these differences, and without these rules, it’s simply a matter of fact that the atoms, molecules and living things we see today wouldn’t be possible to create.

The way that atoms link up to form molecules, including organic molecules and biological processes, is only possible because of the Pauli exclusion rule that governs electrons. Image credit: Jenny Mottar.

The way that atoms link up to form molecules, including organic molecules and biological processes, is only possible because of the Pauli exclusion rule that governs electrons. Image credit: Jenny Mottar.

What’s the difference between fermions and bosons? A little difference goes a long way! Find out on this edition of Ask Ethan.



from ScienceBlogs http://ift.tt/2otxKr0

“The layman always means, when he says “reality” that he is speaking of something self-evidently known; whereas to me it seems the most important and exceedingly difficult task of our time is to work on the construction of a new idea of reality.” -Wolfgang Pauli

On the surface, it shouldn’t appear to make all that much difference to the Universe whether a particle has a spin in half-integer intervals (±1/2, ±3/2, ±5/2) or in integer intervals (0, ±1, ±2). The former is what defines fermions, while the latter defines bosons. This hardly seems like an important distinction, since intrinsic angular momentum is such a nebulous property to our intuitions, unlike, say, mass or electric charge.

The known particles in the Standard Model. These are all the fundamental particles that have been directly discovered; the graviton, although undiscovered, would be a spin=2 boson. Image credit: E. Siegel.

The known particles in the Standard Model. These are all the fundamental particles that have been directly discovered; the graviton, although undiscovered, would be a spin=2 boson. Image credit: E. Siegel.

Yet this simple, minor difference carries with it two incredible consequences: one for the existence of distinct particles for antimatter and one for the Pauli exclusion principle, that are required for matter as we know it to be. Without these differences, and without these rules, it’s simply a matter of fact that the atoms, molecules and living things we see today wouldn’t be possible to create.

The way that atoms link up to form molecules, including organic molecules and biological processes, is only possible because of the Pauli exclusion rule that governs electrons. Image credit: Jenny Mottar.

The way that atoms link up to form molecules, including organic molecules and biological processes, is only possible because of the Pauli exclusion rule that governs electrons. Image credit: Jenny Mottar.

What’s the difference between fermions and bosons? A little difference goes a long way! Find out on this edition of Ask Ethan.



from ScienceBlogs http://ift.tt/2otxKr0
Aucun commentaire:
Libellés :

April’s birthstone is the diamond

Photo via Kim Alianz

Our annual fund-raiser is here! Help EarthSky stay an independent voice.

April’s birthstone is the diamond.

Diamonds are the rich cousins of graphite. Both are crystalline forms of pure carbon. The enormous differences in their properties are a result of the way the carbon atoms are bonded together. In graphite, carbon atoms are arranged in sheets that easily slide past each other, which makes graphite ideal as a lubricant and, of course, pencil lead. Diamond crystals, on the other hand, are a tight-fisted network of carbon atoms securely held in four directions, making it the hardest naturally-occurring substance in the world.

In order to achieve such a compact and strongly-held network of carbon atoms, it is believed that diamonds must have crystallized deep under the Earth’s surface. At these depths the proper conditions for the formation of diamonds exist; at 90 to 120 miles deep, pressures are more than 65,000 times that of the atmosphere at the Earth’s surface, with temperatures exceeding 2,700 degrees Fahrenheit. Such pressures and temperatures reproduced in laboratories have successfully yielded synthetic diamonds.

There are many kinds of diamonds: transparent, translucent, or opaque; ranging from colorless to sooty black, with many colors in between. Mostly transparent diamonds, colorless or tinted, are used as jewelry. Others are used widely in industry. The color of a diamond depends on the kind of impurities embedded inside it. Yellow diamonds, for example, betray minute quantities of nitrogen, while boron imparts a bluish hue. There are other inclusions in diamonds that have great scientific value. Such samples are time capsules that yield valuable information about conditions deep in the Earth’s upper mantle where diamonds formed, as well as clues to the formation and age of the diamond.

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

Diamonds are found in alluvial deposits – gravel swept by streams, rivers, glaciers, and ocean currents. They are also found in sedimentary rock where gravel deposits and organic material have been compressed into rock. Diamonds can be found in some samples of kimberlite – a type of volcanic rock first identified in Kimberley, South Africa. Diamonds found in kimberlite are thought to be very old, perhaps as much as three billion years old. Tiny flecks of diamond have even been found inside meteorites – bits of rocky space debris that land on Earth.

Diamonds are crystals. Crystals are the ultimate form of symmetry in nature. Their shape reflects the internal orderly arrangement of atoms within the crystal. In diamonds, atoms of carbon are held tightly by covalent bonding, where two neighboring atoms share an electron, endowing the diamond crystal with great strength. But despite that hardness, diamonds can be cut with saws and polished with grinding wheels coated with tiny industrial diamond fragments. In their natural form, diamonds can appear quite unimpressive. They are cut and polished by skilled craftsmen in a pattern that reflects and refracts the light among its facets to reveal the hidden beauty of the stone.

Diamonds’ cold, sparkling fire has held us spell-bound for centuries, inspiring rich, passionate myths of romance, intrigue, power, greed, and magic. Ancient Hindus, finding diamonds washed out of the ground after thunderstorms, believed they were created by bolts of lightning. In our place and time, the diamond is a symbol of enduring love, and often graces engagement rings.

diamond

Some diamonds seem to have lived lives of their own. One legendary stone in the diamond hall of fame is the Koh-i-noor (“Mountain of Light”). The Koh-i-noor diamond’s early history is shrouded in time. It is believed to be 5,000 years old, and was featured in the great Sanskrit epic The Mahabharata. Originally owned by the Rajah of Malwa in India, the Koh-i-noor has since been a player in victories and defeats spanning India, Persia, and Afghanistan. It was in the possession of the great Mogul dynasty from 1526 to 1739. Its owners included Shah Jehan, who built the Taj Mahal in memory of his queen Mumtaz. The Persian invader Nadir Shah briefly possessed it until his assassination in 1747. The jewel then fell into the hands of Afghan rulers who eventually surrendered it to the Rajah of Punjab, Ranjit Singh.

Two years after Ranjit Singh’s death in 1839, Punjab became part of India under British rule. The stone was presented to Queen Victoria, who had it cut from its original 187 carats to 108 carats in an attempt to further enhance its beauty. After her death, the diamond became part of the British crown jewels. Queen Elizabeth (later the Queen Mother) wore it in her crown at her 1937 coronation.

Find out about the birthstones for the other months of the year.
January birthstone
February birthstone
March birthstone
May birthstone
June birthstone
July birthstone
August birthstone
September birthstone
October birthstone
November birthstone
December birthstone

Bottom line: Information about April’s birthstone, the diamond.



from EarthSky http://ift.tt/1i0DZGT

Photo via Kim Alianz

Our annual fund-raiser is here! Help EarthSky stay an independent voice.

April’s birthstone is the diamond.

Diamonds are the rich cousins of graphite. Both are crystalline forms of pure carbon. The enormous differences in their properties are a result of the way the carbon atoms are bonded together. In graphite, carbon atoms are arranged in sheets that easily slide past each other, which makes graphite ideal as a lubricant and, of course, pencil lead. Diamond crystals, on the other hand, are a tight-fisted network of carbon atoms securely held in four directions, making it the hardest naturally-occurring substance in the world.

In order to achieve such a compact and strongly-held network of carbon atoms, it is believed that diamonds must have crystallized deep under the Earth’s surface. At these depths the proper conditions for the formation of diamonds exist; at 90 to 120 miles deep, pressures are more than 65,000 times that of the atmosphere at the Earth’s surface, with temperatures exceeding 2,700 degrees Fahrenheit. Such pressures and temperatures reproduced in laboratories have successfully yielded synthetic diamonds.

There are many kinds of diamonds: transparent, translucent, or opaque; ranging from colorless to sooty black, with many colors in between. Mostly transparent diamonds, colorless or tinted, are used as jewelry. Others are used widely in industry. The color of a diamond depends on the kind of impurities embedded inside it. Yellow diamonds, for example, betray minute quantities of nitrogen, while boron imparts a bluish hue. There are other inclusions in diamonds that have great scientific value. Such samples are time capsules that yield valuable information about conditions deep in the Earth’s upper mantle where diamonds formed, as well as clues to the formation and age of the diamond.

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

Diamonds are found in alluvial deposits – gravel swept by streams, rivers, glaciers, and ocean currents. They are also found in sedimentary rock where gravel deposits and organic material have been compressed into rock. Diamonds can be found in some samples of kimberlite – a type of volcanic rock first identified in Kimberley, South Africa. Diamonds found in kimberlite are thought to be very old, perhaps as much as three billion years old. Tiny flecks of diamond have even been found inside meteorites – bits of rocky space debris that land on Earth.

Diamonds are crystals. Crystals are the ultimate form of symmetry in nature. Their shape reflects the internal orderly arrangement of atoms within the crystal. In diamonds, atoms of carbon are held tightly by covalent bonding, where two neighboring atoms share an electron, endowing the diamond crystal with great strength. But despite that hardness, diamonds can be cut with saws and polished with grinding wheels coated with tiny industrial diamond fragments. In their natural form, diamonds can appear quite unimpressive. They are cut and polished by skilled craftsmen in a pattern that reflects and refracts the light among its facets to reveal the hidden beauty of the stone.

Diamonds’ cold, sparkling fire has held us spell-bound for centuries, inspiring rich, passionate myths of romance, intrigue, power, greed, and magic. Ancient Hindus, finding diamonds washed out of the ground after thunderstorms, believed they were created by bolts of lightning. In our place and time, the diamond is a symbol of enduring love, and often graces engagement rings.

diamond

Some diamonds seem to have lived lives of their own. One legendary stone in the diamond hall of fame is the Koh-i-noor (“Mountain of Light”). The Koh-i-noor diamond’s early history is shrouded in time. It is believed to be 5,000 years old, and was featured in the great Sanskrit epic The Mahabharata. Originally owned by the Rajah of Malwa in India, the Koh-i-noor has since been a player in victories and defeats spanning India, Persia, and Afghanistan. It was in the possession of the great Mogul dynasty from 1526 to 1739. Its owners included Shah Jehan, who built the Taj Mahal in memory of his queen Mumtaz. The Persian invader Nadir Shah briefly possessed it until his assassination in 1747. The jewel then fell into the hands of Afghan rulers who eventually surrendered it to the Rajah of Punjab, Ranjit Singh.

Two years after Ranjit Singh’s death in 1839, Punjab became part of India under British rule. The stone was presented to Queen Victoria, who had it cut from its original 187 carats to 108 carats in an attempt to further enhance its beauty. After her death, the diamond became part of the British crown jewels. Queen Elizabeth (later the Queen Mother) wore it in her crown at her 1937 coronation.

Find out about the birthstones for the other months of the year.
January birthstone
February birthstone
March birthstone
May birthstone
June birthstone
July birthstone
August birthstone
September birthstone
October birthstone
November birthstone
December birthstone

Bottom line: Information about April’s birthstone, the diamond.



from EarthSky http://ift.tt/1i0DZGT
Aucun commentaire:
Libellés :

My new job: CEO of the United States National Parks Service Library System [Confessions of a Science Librarian]

You know, I’m the best librarian. Just the best. My collection is huge. The very very best collection. Such a great collection. I love collecting. I’m very good at bibliographic instruction. Nobody does bibliographic instruction like me. Students love it. I can talk for hours. I have long, beautiful book stacks. Look at those book stacks, are they small book stacks? I guarantee you there’s no problem. I guarantee you.

And since I’m the best librarian, my pal The Donald, the President of the United States, has hired me to be the Chief Executive Officer for the National Parks Service Library System.

We all know how much he loves books, right?

Now I know that following my various job changes over the years seems a bit wearying, even for me, especially since I can’t seem to stick with anything for more than a year. Every April, like clockwork, there seems to be a new announcement. Whether it’s a group blog for revolutionary librarians, Chief Science Librarian for the Canadian Federal Government, launching a new journal, IJUST-CANT or JAPE.

Before making this historic announcement, I definitely wanted to get a management team into place. A better group of people could not be found to make the National Parks Services Library System great again! I am so proud to name my new team!

Chair of the Board: Yevgeny Zamyatin
Associate Director: Winston Smith
Associate Director, Branch Libraries: Aldous Orwell
Head of Collections, Fiction: Emmanuel Goldstein
Head of Collections, Non-Fiction: Julia O’Brien
Head of Reference Services: Offred Atwood

What’s JOB ONE you ask? Making our collections great again! To that end, I am directing our Heads of Collections to immediately and with full force to set our collections budget to zero dollars. We will no longer be purchasing any materials for our libraries and will only be relying on our deal-making abilities to fill our shelves with freebies from all the most famous American and foreign authors. You’ll love these books. You’ll love them like you’ve never loved a book before.

As of this moment, we will only be stocking books by the following authors:

  • Donald Trump
  • Newt Gingrich
  • Ann Coulter
  • Roger Stone
  • Sean Hannity
  • Sheriff David A. Clarke Jr.
  • Michael Savage
  • Bill O’Reilly
  • David Horowitz
  • Glenn Beck (classic books only)
  • Sarah Palin
  • Rush Limbaugh

Effective immediately, anyone who can prove they have read the timeless classic, The Art of the Deal, will be allowed free entrance into any National Park.

All music CDs held by our libraries will be by Ted Nugent. No exceptions. Except for whoever it was that sang at the inauguration. What’s-their-names.

I’m still looking for people to appoint as Heads of the various individual branch libraries in the various national parks, although I will personally be based at Badlands National Park and will serve as the head of that library.

As mentioned earlier, we will be removing all books currently in stock and replacing them with new improved ones. Here’s a list of all the books we will be removing from our collections.

I’d also like to mention a few more recent books which we will not be acquiring for our collection. Don’t read these books. They are fake news books.

As usual, I’m happy for suggestions about what books we should not purchase for our libraries!

===

Here’s a list of my previous blog posts about how Donald Trump is going to make science and libraries great again!



from ScienceBlogs http://ift.tt/2ntCqMs

You know, I’m the best librarian. Just the best. My collection is huge. The very very best collection. Such a great collection. I love collecting. I’m very good at bibliographic instruction. Nobody does bibliographic instruction like me. Students love it. I can talk for hours. I have long, beautiful book stacks. Look at those book stacks, are they small book stacks? I guarantee you there’s no problem. I guarantee you.

And since I’m the best librarian, my pal The Donald, the President of the United States, has hired me to be the Chief Executive Officer for the National Parks Service Library System.

We all know how much he loves books, right?

Now I know that following my various job changes over the years seems a bit wearying, even for me, especially since I can’t seem to stick with anything for more than a year. Every April, like clockwork, there seems to be a new announcement. Whether it’s a group blog for revolutionary librarians, Chief Science Librarian for the Canadian Federal Government, launching a new journal, IJUST-CANT or JAPE.

Before making this historic announcement, I definitely wanted to get a management team into place. A better group of people could not be found to make the National Parks Services Library System great again! I am so proud to name my new team!

Chair of the Board: Yevgeny Zamyatin
Associate Director: Winston Smith
Associate Director, Branch Libraries: Aldous Orwell
Head of Collections, Fiction: Emmanuel Goldstein
Head of Collections, Non-Fiction: Julia O’Brien
Head of Reference Services: Offred Atwood

What’s JOB ONE you ask? Making our collections great again! To that end, I am directing our Heads of Collections to immediately and with full force to set our collections budget to zero dollars. We will no longer be purchasing any materials for our libraries and will only be relying on our deal-making abilities to fill our shelves with freebies from all the most famous American and foreign authors. You’ll love these books. You’ll love them like you’ve never loved a book before.

As of this moment, we will only be stocking books by the following authors:

  • Donald Trump
  • Newt Gingrich
  • Ann Coulter
  • Roger Stone
  • Sean Hannity
  • Sheriff David A. Clarke Jr.
  • Michael Savage
  • Bill O’Reilly
  • David Horowitz
  • Glenn Beck (classic books only)
  • Sarah Palin
  • Rush Limbaugh

Effective immediately, anyone who can prove they have read the timeless classic, The Art of the Deal, will be allowed free entrance into any National Park.

All music CDs held by our libraries will be by Ted Nugent. No exceptions. Except for whoever it was that sang at the inauguration. What’s-their-names.

I’m still looking for people to appoint as Heads of the various individual branch libraries in the various national parks, although I will personally be based at Badlands National Park and will serve as the head of that library.

As mentioned earlier, we will be removing all books currently in stock and replacing them with new improved ones. Here’s a list of all the books we will be removing from our collections.

I’d also like to mention a few more recent books which we will not be acquiring for our collection. Don’t read these books. They are fake news books.

As usual, I’m happy for suggestions about what books we should not purchase for our libraries!

===

Here’s a list of my previous blog posts about how Donald Trump is going to make science and libraries great again!



from ScienceBlogs http://ift.tt/2ntCqMs
Aucun commentaire:
Libellés :

Mercury after sunset in early April

Help EarthSky stay an independent voice! Donate here.

Tonight – April 1, 2017 – just might be your night to view the elusive planet Mercury in the western sky after sunset – if you look outside only shortly after sunset – and if you live in the Northern Hemisphere or the tropics. Look for Mercury over the sunset point on the horizon, starting around 45 to 60 minutes after sunset.

Although Mercury can be seen with the eye alone, binoculars always come in handy for any Mercury search.

Mercury, the innermost planet of the solar system, swings between our morning and evening sky and often hides in the sun’s glare. But, on April 1, Mercury swings farthest east of the setting sun (19o) on the sky’s dome during its present apparition as the evening “star.” The current apparition started officially on March 7, 2017 and will end on April 20, 2017. But the best time to see Mercury is around the middle of that period, in other words, around now.

That means Mercury is staying out for a maximum time after sunset (90 minutes or more at mid-northern latitudes) in early April, 2017.

Find an almanac telling you Mercury’s setting time in your sky

Whenever Mercury reaches its greatest evening elongation (maximum angular distance east of the setting sun) in early spring, Mercury stages its best showing in the evening sky. Because it’s now early autumn in the Southern Hemisphere, this greatest elongation of Mercury is an especially poor one for southerly latitudes.

But don’t despair if you live at temperate latitudes in the Southern Hemisphere. You’ll have a super apparition of Mercury in the morning sky in May 2017 while the Northern Hemisphere will have a very poor one.

Wherever you are, if you want to try to catch Mercury now, find an unobstructed horizon in the direction of sunset and scan for Mercury near the sunset point on the horizon as dusk gives way to darkness.

Bottom line: The first week of April 2017 provides you with a golden opportunity to catch Mercury, the planet that’s often lost in the glare of the sun.



from EarthSky http://ift.tt/2lmic5K

Help EarthSky stay an independent voice! Donate here.

Tonight – April 1, 2017 – just might be your night to view the elusive planet Mercury in the western sky after sunset – if you look outside only shortly after sunset – and if you live in the Northern Hemisphere or the tropics. Look for Mercury over the sunset point on the horizon, starting around 45 to 60 minutes after sunset.

Although Mercury can be seen with the eye alone, binoculars always come in handy for any Mercury search.

Mercury, the innermost planet of the solar system, swings between our morning and evening sky and often hides in the sun’s glare. But, on April 1, Mercury swings farthest east of the setting sun (19o) on the sky’s dome during its present apparition as the evening “star.” The current apparition started officially on March 7, 2017 and will end on April 20, 2017. But the best time to see Mercury is around the middle of that period, in other words, around now.

That means Mercury is staying out for a maximum time after sunset (90 minutes or more at mid-northern latitudes) in early April, 2017.

Find an almanac telling you Mercury’s setting time in your sky

Whenever Mercury reaches its greatest evening elongation (maximum angular distance east of the setting sun) in early spring, Mercury stages its best showing in the evening sky. Because it’s now early autumn in the Southern Hemisphere, this greatest elongation of Mercury is an especially poor one for southerly latitudes.

But don’t despair if you live at temperate latitudes in the Southern Hemisphere. You’ll have a super apparition of Mercury in the morning sky in May 2017 while the Northern Hemisphere will have a very poor one.

Wherever you are, if you want to try to catch Mercury now, find an unobstructed horizon in the direction of sunset and scan for Mercury near the sunset point on the horizon as dusk gives way to darkness.

Bottom line: The first week of April 2017 provides you with a golden opportunity to catch Mercury, the planet that’s often lost in the glare of the sun.



from EarthSky http://ift.tt/2lmic5K
Aucun commentaire:
Libellés :

News digest – cutting sugar, a new NHS target, lab-grown mini tumours, and… vitamin C as a treatment?

pexels-photo-48699_oranges
  • Voluntary guidelines to reduce children’s sugar intake have been released, with proposed limits set for 9 foods, including breakfast cereals and biscuits. It’s hoped that the measures will cut sugar consumption by 20% over the next 3 years, but we’ve been clear that the food industry really needs to act now to make this happen. We reported on the story as did the Guardian.
  • NHS England has set a target of 5,000 more people each year to survive cancer by 2019. It will also introduce a new 28 day target for patients to be diagnosed or given the all clear following a referral, as we reported. It remains to be seen how successful this will be given the shocking recent record of meeting targets, particularly when budgets, resources and staff are already stretched. The Daily Mail also reported this one.
  • It seems we’re talking every week about NHS waiting times being missed, and this time it’s the turn of Scotland. The target of 62 days from referral to beginning treatment hasn’t been met for around 4 years now, and we’ve said that it’s absolutely critical that improvements are seen soon. The Times, BBC and Scotsman all covered the story.

Number of the week

5,000 – the extra number of people NHS England hopes will survive their cancer by 2019

  • And it’s a similar picture in Northern Ireland with only 68% of cancer patients starting treatment within 62 days of an urgent referral, falling way short of the 95% target. The Belfast Telegraph covered this one.
  • A plan for children whose cancers don’t respond to conventional treatment to have their tumour DNA sequenced as a possible way to suggest different treatments was reported by the Telegraph and Sky News, but not all children will be offered this.
  • With the Pill in the news again last week, the Guardian looked in a little more detail at how it affects cancer risk. We’ve also got more information.
  • We spoke to the Express about why survival for pancreatic cancer is so low, and what we’re trying to do about it.
  • An Australian study reported that keyhole surgery is a better approach for women with early stage womb cancer than the more invasive surgery that is commonly used. Our news report has more.
  • We launched a clinical trial in GP surgeries testing a ‘sponge-on-a-string’ as a possible way to detect Barrett’s oesophagus – a condition that can increase the risk of developing oesophageal cancer. Our press release has the details.

  • BBC News and the Express reported on a new method to help GPs assess the risk of bowel cancer in people under 50. The symptoms of bowel cancer are more likely to be down to other, less serious, conditions and this can make it harder for GPs to know who needs further tests. Early diagnosis is important as it means treatment is more likely to be successful.
  • A team looked at the genetics of a number of brain tumours, finding new variations in the DNA that might be useful in assessing risk of the disease, but the effects of the variants were small. Larger studies will be needed to test the impact the discovery might have on brain tumour research. The Mirror reported on this one.

And finally

  • The Express and Evening Standard covered a study looking at vitamin C and cancer, but the headlines didn’t reflect the findings of the study. While the results were encouraging, the study was designed to look at safety rather than effectiveness of high-dose vitamin C combined with standard treatment, not to determine if this was more effective than standard treatment alone. The study included just 11 brain tumour patients, so it’s far too early to conclude that “Vitamin C can beat cancer”.

Michael



from Cancer Research UK – Science blog http://ift.tt/2npwrYn
pexels-photo-48699_oranges
  • Voluntary guidelines to reduce children’s sugar intake have been released, with proposed limits set for 9 foods, including breakfast cereals and biscuits. It’s hoped that the measures will cut sugar consumption by 20% over the next 3 years, but we’ve been clear that the food industry really needs to act now to make this happen. We reported on the story as did the Guardian.
  • NHS England has set a target of 5,000 more people each year to survive cancer by 2019. It will also introduce a new 28 day target for patients to be diagnosed or given the all clear following a referral, as we reported. It remains to be seen how successful this will be given the shocking recent record of meeting targets, particularly when budgets, resources and staff are already stretched. The Daily Mail also reported this one.
  • It seems we’re talking every week about NHS waiting times being missed, and this time it’s the turn of Scotland. The target of 62 days from referral to beginning treatment hasn’t been met for around 4 years now, and we’ve said that it’s absolutely critical that improvements are seen soon. The Times, BBC and Scotsman all covered the story.

Number of the week

5,000 – the extra number of people NHS England hopes will survive their cancer by 2019

  • And it’s a similar picture in Northern Ireland with only 68% of cancer patients starting treatment within 62 days of an urgent referral, falling way short of the 95% target. The Belfast Telegraph covered this one.
  • A plan for children whose cancers don’t respond to conventional treatment to have their tumour DNA sequenced as a possible way to suggest different treatments was reported by the Telegraph and Sky News, but not all children will be offered this.
  • With the Pill in the news again last week, the Guardian looked in a little more detail at how it affects cancer risk. We’ve also got more information.
  • We spoke to the Express about why survival for pancreatic cancer is so low, and what we’re trying to do about it.
  • An Australian study reported that keyhole surgery is a better approach for women with early stage womb cancer than the more invasive surgery that is commonly used. Our news report has more.
  • We launched a clinical trial in GP surgeries testing a ‘sponge-on-a-string’ as a possible way to detect Barrett’s oesophagus – a condition that can increase the risk of developing oesophageal cancer. Our press release has the details.

  • BBC News and the Express reported on a new method to help GPs assess the risk of bowel cancer in people under 50. The symptoms of bowel cancer are more likely to be down to other, less serious, conditions and this can make it harder for GPs to know who needs further tests. Early diagnosis is important as it means treatment is more likely to be successful.
  • A team looked at the genetics of a number of brain tumours, finding new variations in the DNA that might be useful in assessing risk of the disease, but the effects of the variants were small. Larger studies will be needed to test the impact the discovery might have on brain tumour research. The Mirror reported on this one.

And finally

  • The Express and Evening Standard covered a study looking at vitamin C and cancer, but the headlines didn’t reflect the findings of the study. While the results were encouraging, the study was designed to look at safety rather than effectiveness of high-dose vitamin C combined with standard treatment, not to determine if this was more effective than standard treatment alone. The study included just 11 brain tumour patients, so it’s far too early to conclude that “Vitamin C can beat cancer”.

Michael



from Cancer Research UK – Science blog http://ift.tt/2npwrYn
Aucun commentaire:
Libellés :
Inscription à : Articles (Atom)