It's Computer Security Day! Here are 5 quick ways to make sure yours is secure.
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It's Computer Security Day! Here are 5 quick ways to make sure yours is secure.from http://ift.tt/2AJmbVQ
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Bright moon and aurora borealis
A composite of 6 overhead photos of the aurora and a bright moon – just 3 days past full – from Doug Short in Anchorage, Alaska. November 7, 2017.
Auroras are beautiful natural phenomena, whose primary cause is activity on the sun. They happen when charged particles from storms on the sun strike atoms and molecules in Earth’s atmosphere. The charged solar particles excite those earthly atoms, causing them to light up, creating the aurora. This sort of activity in Earth’s atmosphere happens during geomagnetic storms, and a full moon has absolutely no effect on either solar storms or geomagnetic storms. Still, as every astronomer knows, a full moon casts a lot of light in the sky. Can that light drown an aurora from view?
The answer depends on the strength of the aurora. A weak auroral display might be drowned in bright moonlight, just as bright moonlight can drown faint stars from view.
But, as the photos on this page show, a strong auroral display can withstand bright moonlight. AndyOz, who wrote a particularly good article on this subject, which you can access here, wrote:
If you get a moderate to high level of [auroral] activity … you should still get a good view of the northern lights. In some cases when there has been a solar storm and the level of activity is very high, the moon can actually enhance the viewing and make the display look even more magical. So it all really depends on how strong a display you are witnessing.
Aurora borealis and rising moon on February 14, 2013 from EarthSky Facebook friend Stigs Netrom in northern Norway.
Some photographers say they actually prefer to capture the aurora when there’s a moon in the sky. Todd Salat at the website AuroraHunter.com wrote of shooting the aurora in moonlight:
I personally like moonlight because it lights up the foreground and makes the sky a deep blue instead of pitch black like with no moon. I watch the lunar phase very carefully.
View larger. | Aurora and a full moon. Photo by Antti Pietikainen via the Aurora Zone. Antti created this mosaic from 10 images, taken from his backyard. He said the weather was good, no clouds and very cold. The moon was high in the sky, and it illuminated the whole landscape. “You could read a book outside!”
Bottom line: Contrary to what you might have heard, it is possible to see the aurora borealis, or northern lights, when there’s a bright moon, even a full moon, in the sky. The key is that the auroral display itself be moderate to strong. A weak display of the aurora might be drowned in bright moonlight.
What causes the aurora borealis or northern lights?
from EarthSky http://ift.tt/2zS1IhW
A composite of 6 overhead photos of the aurora and a bright moon – just 3 days past full – from Doug Short in Anchorage, Alaska. November 7, 2017.
Auroras are beautiful natural phenomena, whose primary cause is activity on the sun. They happen when charged particles from storms on the sun strike atoms and molecules in Earth’s atmosphere. The charged solar particles excite those earthly atoms, causing them to light up, creating the aurora. This sort of activity in Earth’s atmosphere happens during geomagnetic storms, and a full moon has absolutely no effect on either solar storms or geomagnetic storms. Still, as every astronomer knows, a full moon casts a lot of light in the sky. Can that light drown an aurora from view?
The answer depends on the strength of the aurora. A weak auroral display might be drowned in bright moonlight, just as bright moonlight can drown faint stars from view.
But, as the photos on this page show, a strong auroral display can withstand bright moonlight. AndyOz, who wrote a particularly good article on this subject, which you can access here, wrote:
If you get a moderate to high level of [auroral] activity … you should still get a good view of the northern lights. In some cases when there has been a solar storm and the level of activity is very high, the moon can actually enhance the viewing and make the display look even more magical. So it all really depends on how strong a display you are witnessing.
Aurora borealis and rising moon on February 14, 2013 from EarthSky Facebook friend Stigs Netrom in northern Norway.
Some photographers say they actually prefer to capture the aurora when there’s a moon in the sky. Todd Salat at the website AuroraHunter.com wrote of shooting the aurora in moonlight:
I personally like moonlight because it lights up the foreground and makes the sky a deep blue instead of pitch black like with no moon. I watch the lunar phase very carefully.
View larger. | Aurora and a full moon. Photo by Antti Pietikainen via the Aurora Zone. Antti created this mosaic from 10 images, taken from his backyard. He said the weather was good, no clouds and very cold. The moon was high in the sky, and it illuminated the whole landscape. “You could read a book outside!”
Bottom line: Contrary to what you might have heard, it is possible to see the aurora borealis, or northern lights, when there’s a bright moon, even a full moon, in the sky. The key is that the auroral display itself be moderate to strong. A weak display of the aurora might be drowned in bright moonlight.
What causes the aurora borealis or northern lights?
from EarthSky http://ift.tt/2zS1IhW
Lunar halo and clouds over Tucson
Moon rocketing into a halo? No. In fact, the “contrail” is really clouds, and the moon itself – plus ice crystals in the air – made this halo, which skywatchers call a 22-degree halo. Photo taken over Tucson, Arizona – November 29, 2017 – by Eliot Herman. Irex 15 mm lens and Nikon D850 camera.
What makes a halo around the sun or moon?
from EarthSky http://ift.tt/2kbuUcy
Moon rocketing into a halo? No. In fact, the “contrail” is really clouds, and the moon itself – plus ice crystals in the air – made this halo, which skywatchers call a 22-degree halo. Photo taken over Tucson, Arizona – November 29, 2017 – by Eliot Herman. Irex 15 mm lens and Nikon D850 camera.
What makes a halo around the sun or moon?
from EarthSky http://ift.tt/2kbuUcy
Do songbirds share ‘universal grammar’?
EarthSky’s 2018 lunar calendars are here! Get yours while they last.
Many scientists who study birdsong are intrigued by the possibility that human speech and music may be rooted in biological processes shared across a variety of animals. Now, new research, published online in Current Biology on November 22, 2017, provides new evidence to support the idea that songbirds and humans have common biological hardwiring that shapes how they produce and perceive sounds.
In a series of experiments, the researchers found that young zebra finches – a species often used to study birdsong – are intrinsically biased to learn to produce particular kinds of sound patterns over others.
Jon Sakata, Associate Professor of Biology at McGill University, is the paper’s senior author. Sakata said in a statement:
In addition, these sound patterns resembled patterns that are frequently observed across human languages and in music.
Zebra finches. Image via Raina Fan.
The idea for the experiments, say the researchers, was inspired by current hypotheses on human language and music. Linguists have long found that the world’s languages share many common features, termed “universals.” These features encompass the syntactic structure of languages (e.g., word order) as well as finer acoustic patterns of speech, such as the timing, pitch, and stress of utterances. Some theorists, including Noam Chomsky, have postulated that these patterns reflect a “universal grammar” built on innate brain mechanisms that promote and bias language learning. Researchers continue to debate the extent of these innate brain mechanisms, in part because of the potential for cultural propagation to account for universals.
At the same time, vast surveys of zebra finch songs have documented a variety of acoustic patterns found universally across populations. Logan James, co-author of the study, said:
Because the nature of these universals bears similarity to those in humans and because songbirds learn their vocalizations much in the same way that humans acquire speech and language, we were motivated to test biological predisposition in vocal learning in songbirds.
Read about how the researcher performed their experiments
Caroline Palmer is a Professor of Psychology at McGill who was not involved in the study. She said:
These findings have important contributions for our understanding of human speech and music. The research, which controls the birds’ learning environment in ways that are not possible with young children, suggests that statistical learning alone – the degree to which one is exposed to specific acoustic patterns – cannot account for song (or speech) preferences. Other principles, such as universal grammars and perceptual organization, are more likely to account for why human infants as well as juvenile birds are predisposed to prefer some auditory patterns.
Enjoying EarthSky so far? Sign up for our free daily newsletter today!
Bottom line: New research supports the idea that humans and songbirds share common biological hardwiring that shapes how they produce and perceive sounds.
Read more from McGill University
from EarthSky http://ift.tt/2j1QPPW
EarthSky’s 2018 lunar calendars are here! Get yours while they last.
Many scientists who study birdsong are intrigued by the possibility that human speech and music may be rooted in biological processes shared across a variety of animals. Now, new research, published online in Current Biology on November 22, 2017, provides new evidence to support the idea that songbirds and humans have common biological hardwiring that shapes how they produce and perceive sounds.
In a series of experiments, the researchers found that young zebra finches – a species often used to study birdsong – are intrinsically biased to learn to produce particular kinds of sound patterns over others.
Jon Sakata, Associate Professor of Biology at McGill University, is the paper’s senior author. Sakata said in a statement:
In addition, these sound patterns resembled patterns that are frequently observed across human languages and in music.
Zebra finches. Image via Raina Fan.
The idea for the experiments, say the researchers, was inspired by current hypotheses on human language and music. Linguists have long found that the world’s languages share many common features, termed “universals.” These features encompass the syntactic structure of languages (e.g., word order) as well as finer acoustic patterns of speech, such as the timing, pitch, and stress of utterances. Some theorists, including Noam Chomsky, have postulated that these patterns reflect a “universal grammar” built on innate brain mechanisms that promote and bias language learning. Researchers continue to debate the extent of these innate brain mechanisms, in part because of the potential for cultural propagation to account for universals.
At the same time, vast surveys of zebra finch songs have documented a variety of acoustic patterns found universally across populations. Logan James, co-author of the study, said:
Because the nature of these universals bears similarity to those in humans and because songbirds learn their vocalizations much in the same way that humans acquire speech and language, we were motivated to test biological predisposition in vocal learning in songbirds.
Read about how the researcher performed their experiments
Caroline Palmer is a Professor of Psychology at McGill who was not involved in the study. She said:
These findings have important contributions for our understanding of human speech and music. The research, which controls the birds’ learning environment in ways that are not possible with young children, suggests that statistical learning alone – the degree to which one is exposed to specific acoustic patterns – cannot account for song (or speech) preferences. Other principles, such as universal grammars and perceptual organization, are more likely to account for why human infants as well as juvenile birds are predisposed to prefer some auditory patterns.
Enjoying EarthSky so far? Sign up for our free daily newsletter today!
Bottom line: New research supports the idea that humans and songbirds share common biological hardwiring that shapes how they produce and perceive sounds.
Read more from McGill University
from EarthSky http://ift.tt/2j1QPPW
2017 marks 50 years since pulsars were discovered
by George Hobbs, CSIRO; Dick Manchester, CSIRO, and Simon Johnston, CSIRO
A pulsar is a small, spinning star – a giant ball of neutrons, left behind after a normal star has died in a fiery explosion.
With a diameter of only 30 kilometers (18.6 miles), the star spins up to hundreds of times a second, while sending out a beam of radio waves (and sometimes other radiation, such as X-rays). When the beam is pointed in our direction and into our telescopes, we see a pulse.
2017 marks 50 years since pulsars were discovered. In that time, we have found more than 2,600 pulsars (mostly in the Milky Way), and used them to hunt for low-frequency gravitational waves, to determine the structure of our galaxy and to test the general theory of relativity.
Read more: At last, we’ve found gravitational waves from a collapsing pair of neutron stars
CSIRO Parkes radio telescope has discovered around half of all known pulsars. Image via Wayne England.
The discovery
In mid-1967, when thousands of people were enjoying the summer of love, a young PhD student at the University of Cambridge in the UK was helping to build a telescope.
It was a poles-and-wires affair – what astronomers call a “dipole array”. It covered a bit less than two hectares, the area of 57 tennis courts.
By July it was built. The student, Jocelyn Bell (now Dame Jocelyn Bell Burnell), became responsible for running it and analyzing the data it churned out. The data came in the form of pen-on-paper chart records, more than 30 meters (98 feet) of them each day. Bell analyzed them by eye.
Jocelyn Bell Burnell, who discovered the first pulsar.
What she found – a little bit of “scruff” on the chart records – has gone down in history.
Like most discoveries, it took place over time. But there was a turning point. On November 28, 1967, Bell and her supervisor, Antony Hewish, were able to capture a “fast recording” – that is, a detailed one – of one of the strange signals.
In this she could see for the first time that the “scruff” was actually a train of pulses spaced by one-and-a-third seconds. Bell and Hewish had discovered pulsars.
But this wasn’t immediately obvious to them. Following Bell’s observation they worked for two months to eliminate mundane explanations for the signals.
Bell also found another three sources of pulses, which helped to scotch some rather more exotic explanations, such as the idea that the signals came from “little green men” in extraterrestrial civilizations. The discovery paper appeared in Nature on February 24, 1968.
Later, Bell missed out when Hewish and his colleague Sir Martin Ryle were awarded the 1974 Nobel Prize in Physics.
A pulsar on ‘the pineapple’
CSIRO’s Parkes radio telescope in Australia made its first observation of a pulsar in 1968, later made famous by appearing (along with the Parkes telescope) on the first Australian $50 note.
Australia’s first $50 note featured the Parkes telescope and a pulsar.
Fifty years later, Parkes has found more than half of the known pulsars. The University of Sydney’s Molonglo Telescope also played a central role, and they both remain active in finding and timing pulsars today.
Internationally, one of the most exciting new instruments on the scene is China’s Five-hundred-metre Aperture Spherical Telescope, or FAST. FAST has recently found several new pulsars, confirmed by the Parkes telescope and a team of CSIRO astronomers working with their Chinese colleagues.
Why look for pulsars?
We want to understand what pulsars are, how they work, and how they fit into the general population of stars. The extreme cases of pulsars – those that are super fast, super slow, or extremely massive – help to limit the possible models for how pulsars work, telling us more about the structure of matter at ultra-high densities. To find these extreme cases, we need to find lots of pulsars.
Pulsars often orbit companion stars in binary systems, and the nature of these companions helps us understand the formation history of the pulsars themselves. We’ve made good progress with the “what” and “how” of pulsars but there are still unanswered questions.
As well as understanding pulsars themselves, we also use them as a clock. For example, pulsar timing is being pursued as a way to detect the background rumble of low-frequency gravitational waves throughout the universe.
Pulsars have also been used to measure the structure of our galaxy, by looking at the way their signals are altered as they travel through denser regions of material in space.
Pulsars are also one of the finest tools we have for testing Einstein’s theory of general relativity.
Read more: Explainer: Einstein’s Theory of General Relativity
This theory has survived 100 years of the most sophisticated tests astronomers have been able throw at it. But it doesn’t play nicely with our other most successful theory of how the universe works, quantum mechanics, so it must have a tiny flaw somewhere. Pulsars help us to try and understand this problem.
What keeps pulsar astronomers up at night (literally!) is the hope of finding a pulsar in orbit around a black hole. This is the most extreme system we can imagine for testing general relativity.
Finally, pulsars have some more down-to-earth applications. We’re using them as a teaching tool in our PULSE@Parkes program, in which students control the Parkes telescope over the Internet and use it to observe pulsars. This program has reached over 1,700 students, in Australia, Japan, China, The Netherlands, United Kingdom and South Africa.
Pulsars also offer promise as a navigation system for guiding craft travelling through deep space. In 2016 China launched a satellite, XPNAV-1, carrying a navigation system that uses periodic X-ray signals from certain pulsars.
Pulsars have changed our our understanding of the universe, and their true importance is still unfolding.
George Hobbs, Team leader for the Parkes Pulsar Timing Array project, CSIRO; Dick Manchester, CSIRO Fellow, CSIRO Astronomy and Space Science, CSIRO, and Simon Johnston, Senior research scientist, CSIRO
This article was originally published on The Conversation. Read the original article.
from EarthSky http://ift.tt/2BAYBbg
by George Hobbs, CSIRO; Dick Manchester, CSIRO, and Simon Johnston, CSIRO
A pulsar is a small, spinning star – a giant ball of neutrons, left behind after a normal star has died in a fiery explosion.
With a diameter of only 30 kilometers (18.6 miles), the star spins up to hundreds of times a second, while sending out a beam of radio waves (and sometimes other radiation, such as X-rays). When the beam is pointed in our direction and into our telescopes, we see a pulse.
2017 marks 50 years since pulsars were discovered. In that time, we have found more than 2,600 pulsars (mostly in the Milky Way), and used them to hunt for low-frequency gravitational waves, to determine the structure of our galaxy and to test the general theory of relativity.
Read more: At last, we’ve found gravitational waves from a collapsing pair of neutron stars
CSIRO Parkes radio telescope has discovered around half of all known pulsars. Image via Wayne England.
The discovery
In mid-1967, when thousands of people were enjoying the summer of love, a young PhD student at the University of Cambridge in the UK was helping to build a telescope.
It was a poles-and-wires affair – what astronomers call a “dipole array”. It covered a bit less than two hectares, the area of 57 tennis courts.
By July it was built. The student, Jocelyn Bell (now Dame Jocelyn Bell Burnell), became responsible for running it and analyzing the data it churned out. The data came in the form of pen-on-paper chart records, more than 30 meters (98 feet) of them each day. Bell analyzed them by eye.
Jocelyn Bell Burnell, who discovered the first pulsar.
What she found – a little bit of “scruff” on the chart records – has gone down in history.
Like most discoveries, it took place over time. But there was a turning point. On November 28, 1967, Bell and her supervisor, Antony Hewish, were able to capture a “fast recording” – that is, a detailed one – of one of the strange signals.
In this she could see for the first time that the “scruff” was actually a train of pulses spaced by one-and-a-third seconds. Bell and Hewish had discovered pulsars.
But this wasn’t immediately obvious to them. Following Bell’s observation they worked for two months to eliminate mundane explanations for the signals.
Bell also found another three sources of pulses, which helped to scotch some rather more exotic explanations, such as the idea that the signals came from “little green men” in extraterrestrial civilizations. The discovery paper appeared in Nature on February 24, 1968.
Later, Bell missed out when Hewish and his colleague Sir Martin Ryle were awarded the 1974 Nobel Prize in Physics.
A pulsar on ‘the pineapple’
CSIRO’s Parkes radio telescope in Australia made its first observation of a pulsar in 1968, later made famous by appearing (along with the Parkes telescope) on the first Australian $50 note.
Australia’s first $50 note featured the Parkes telescope and a pulsar.
Fifty years later, Parkes has found more than half of the known pulsars. The University of Sydney’s Molonglo Telescope also played a central role, and they both remain active in finding and timing pulsars today.
Internationally, one of the most exciting new instruments on the scene is China’s Five-hundred-metre Aperture Spherical Telescope, or FAST. FAST has recently found several new pulsars, confirmed by the Parkes telescope and a team of CSIRO astronomers working with their Chinese colleagues.
Why look for pulsars?
We want to understand what pulsars are, how they work, and how they fit into the general population of stars. The extreme cases of pulsars – those that are super fast, super slow, or extremely massive – help to limit the possible models for how pulsars work, telling us more about the structure of matter at ultra-high densities. To find these extreme cases, we need to find lots of pulsars.
Pulsars often orbit companion stars in binary systems, and the nature of these companions helps us understand the formation history of the pulsars themselves. We’ve made good progress with the “what” and “how” of pulsars but there are still unanswered questions.
As well as understanding pulsars themselves, we also use them as a clock. For example, pulsar timing is being pursued as a way to detect the background rumble of low-frequency gravitational waves throughout the universe.
Pulsars have also been used to measure the structure of our galaxy, by looking at the way their signals are altered as they travel through denser regions of material in space.
Pulsars are also one of the finest tools we have for testing Einstein’s theory of general relativity.
Read more: Explainer: Einstein’s Theory of General Relativity
This theory has survived 100 years of the most sophisticated tests astronomers have been able throw at it. But it doesn’t play nicely with our other most successful theory of how the universe works, quantum mechanics, so it must have a tiny flaw somewhere. Pulsars help us to try and understand this problem.
What keeps pulsar astronomers up at night (literally!) is the hope of finding a pulsar in orbit around a black hole. This is the most extreme system we can imagine for testing general relativity.
Finally, pulsars have some more down-to-earth applications. We’re using them as a teaching tool in our PULSE@Parkes program, in which students control the Parkes telescope over the Internet and use it to observe pulsars. This program has reached over 1,700 students, in Australia, Japan, China, The Netherlands, United Kingdom and South Africa.
Pulsars also offer promise as a navigation system for guiding craft travelling through deep space. In 2016 China launched a satellite, XPNAV-1, carrying a navigation system that uses periodic X-ray signals from certain pulsars.
Pulsars have changed our our understanding of the universe, and their true importance is still unfolding.
George Hobbs, Team leader for the Parkes Pulsar Timing Array project, CSIRO; Dick Manchester, CSIRO Fellow, CSIRO Astronomy and Space Science, CSIRO, and Simon Johnston, Senior research scientist, CSIRO
This article was originally published on The Conversation. Read the original article.
from EarthSky http://ift.tt/2BAYBbg
Hello, Small Magellanic Cloud
Atomic hydrogen gas in the Small Magellanic Cloud, via the Australian Square Kilometer Array Pathfinder (ASKAP)/ CSIRO/ ANU.
Astronomers at Australian National University (ANU) said on November 28, 2017 that they’ve created the most detailed radio image yet of the Small Magellanic Cloud, a famous sky-sight from Earth’s Southern Hemisphere and a dwarf galaxy orbiting our home galaxy, the Milky Way. The image shows the galaxy not in terms of its stars and dust, as optical images do, but in terms of its hydrogen gas. ANU astronomer Naomi McClure-Griffiths, who co-led the study, said:
Hydrogen is the fundamental building block of all galaxies and shows off the more extended structure of a galaxy than its stars and dust.
She said the image reveals distortions to the Small Magellanic Cloud, which likely occurred because of its interactions with the larger galaxies and because of its own star explosions that push gas out of the galaxy:
The outlook for this dwarf galaxy is not good, as it’s likely to eventually be gobbled up by our Milky Way.
Together, the [Large and Small] Magellanic Clouds are characterised by their distorted structures, a bridge of material that connects them, and an enormous stream of hydrogen gas that trails behind their orbit – a bit like a comet.
The Large and Small Magellanic Clouds by Justin Ng of Singapore.
The astronomers said their new radio image helps them understand how the Small Magellanic Cloud – and presumably the several dozen dwarf galaxies orbiting our Milky Way – formed and evolved.
The Commonwealth Scientific and Industrial Research Organization (CSIRO) – the federal government agency for scientific research in Australia – acquired the image via its new radio telescope, called the Australian Square Kilometre Array Pathfinder (ASKAP). Naomi McClure-Griffiths said:
The new image … reveals more gas around the edges of the galaxy, indicating a very dynamic past for the Small Magellanic Cloud. These features are more than three times smaller than we were able to see before and allow us to probe the detailed interaction of the small galaxy and its environment.
The new image (top of post) was created as part of a survey that aims to study the evolution of galaxies.
An optical image of part of the Small Magellanic Cloud via NASA/ ESA/ Hubble Heritage Team/ ANU.
Bottom line: Astronomers at Australian National University have created the most detailed radio image yet of the Small Magellanic Cloud.
from EarthSky http://ift.tt/2BqcMyK
Atomic hydrogen gas in the Small Magellanic Cloud, via the Australian Square Kilometer Array Pathfinder (ASKAP)/ CSIRO/ ANU.
Astronomers at Australian National University (ANU) said on November 28, 2017 that they’ve created the most detailed radio image yet of the Small Magellanic Cloud, a famous sky-sight from Earth’s Southern Hemisphere and a dwarf galaxy orbiting our home galaxy, the Milky Way. The image shows the galaxy not in terms of its stars and dust, as optical images do, but in terms of its hydrogen gas. ANU astronomer Naomi McClure-Griffiths, who co-led the study, said:
Hydrogen is the fundamental building block of all galaxies and shows off the more extended structure of a galaxy than its stars and dust.
She said the image reveals distortions to the Small Magellanic Cloud, which likely occurred because of its interactions with the larger galaxies and because of its own star explosions that push gas out of the galaxy:
The outlook for this dwarf galaxy is not good, as it’s likely to eventually be gobbled up by our Milky Way.
Together, the [Large and Small] Magellanic Clouds are characterised by their distorted structures, a bridge of material that connects them, and an enormous stream of hydrogen gas that trails behind their orbit – a bit like a comet.
The Large and Small Magellanic Clouds by Justin Ng of Singapore.
The astronomers said their new radio image helps them understand how the Small Magellanic Cloud – and presumably the several dozen dwarf galaxies orbiting our Milky Way – formed and evolved.
The Commonwealth Scientific and Industrial Research Organization (CSIRO) – the federal government agency for scientific research in Australia – acquired the image via its new radio telescope, called the Australian Square Kilometre Array Pathfinder (ASKAP). Naomi McClure-Griffiths said:
The new image … reveals more gas around the edges of the galaxy, indicating a very dynamic past for the Small Magellanic Cloud. These features are more than three times smaller than we were able to see before and allow us to probe the detailed interaction of the small galaxy and its environment.
The new image (top of post) was created as part of a survey that aims to study the evolution of galaxies.
An optical image of part of the Small Magellanic Cloud via NASA/ ESA/ Hubble Heritage Team/ ANU.
Bottom line: Astronomers at Australian National University have created the most detailed radio image yet of the Small Magellanic Cloud.
from EarthSky http://ift.tt/2BqcMyK
Sun enters Ophiuchus on November 30
November 30, 2017. If you could see the stars in the daytime, you’d see the sun shining in front of the border of the constellations Ophiuchus and Scorpius on this date. The sun crosses a constellation boundary, into Ophiuchus.
You can’t see the constellation Ophiuchus when the sun lies in front of it. But, each Northern Hemisphere summer, you’ll find this constellation to the north of the bright star Antares in the constellation Scorpius.
At about this time each year, the sun passes out of Scorpius to enter Ophiuchus. Like Scorpius, Ophiuchus is a constellation of the zodiac … but unlike Scorpius, Ophiuchus is not one of the traditional twelve zodiacal constellations.
The sun will remain in front of Ophiuchus until December 18.
The ecliptic – which translates on our sky’s dome as the sun’s annual path in front of the background stars – actually passes through 13 constellations, as defined by the International Astronomical Union (IAU), although this is not commonly known. After all, when you read the horoscope in the daily newspaper or a monthly magazine, you see only 12 constellations, or signs, mentioned.
There are the 12 traditional zodiacal constellations that have been with us since ancient times. The relatively recent addition of Ophiuchus as a member of the zodiac has increased the number to 13.
Today’s constellation boundaries were drawn out by the International Astronomical Union in the 1930s.
View larger. | Ophiuchus the Serpent Bearer.
Look at the chart carefully, and you’ll see that the border between Ophiuchus and the constellation Scorpius for the most part lies just south of, or below, the ecliptic. In ancient times, the Ophuichus-Scorpius border was likely placed to the north of, or above, the ecliptic. Had the International Astronomical Union placed its constellation boundary where the ancients might have, the sun’s annual passing in front of Scorpius would be from about November 23 till December 18, not November 23 to November 30.
Sun in zodiacal constellations 2017
Bottom line: As seen from Earth, the sun passes in front of the constellation Ophiuchus each year from about November 30 to December 18.
Birthday late November to middle December? Here’s your constellation
EarthSky astronomy kits are perfect for beginners. Order today from the EarthSky store
from EarthSky http://ift.tt/1l1yQbj
November 30, 2017. If you could see the stars in the daytime, you’d see the sun shining in front of the border of the constellations Ophiuchus and Scorpius on this date. The sun crosses a constellation boundary, into Ophiuchus.
You can’t see the constellation Ophiuchus when the sun lies in front of it. But, each Northern Hemisphere summer, you’ll find this constellation to the north of the bright star Antares in the constellation Scorpius.
At about this time each year, the sun passes out of Scorpius to enter Ophiuchus. Like Scorpius, Ophiuchus is a constellation of the zodiac … but unlike Scorpius, Ophiuchus is not one of the traditional twelve zodiacal constellations.
The sun will remain in front of Ophiuchus until December 18.
The ecliptic – which translates on our sky’s dome as the sun’s annual path in front of the background stars – actually passes through 13 constellations, as defined by the International Astronomical Union (IAU), although this is not commonly known. After all, when you read the horoscope in the daily newspaper or a monthly magazine, you see only 12 constellations, or signs, mentioned.
There are the 12 traditional zodiacal constellations that have been with us since ancient times. The relatively recent addition of Ophiuchus as a member of the zodiac has increased the number to 13.
Today’s constellation boundaries were drawn out by the International Astronomical Union in the 1930s.
View larger. | Ophiuchus the Serpent Bearer.
Look at the chart carefully, and you’ll see that the border between Ophiuchus and the constellation Scorpius for the most part lies just south of, or below, the ecliptic. In ancient times, the Ophuichus-Scorpius border was likely placed to the north of, or above, the ecliptic. Had the International Astronomical Union placed its constellation boundary where the ancients might have, the sun’s annual passing in front of Scorpius would be from about November 23 till December 18, not November 23 to November 30.
Sun in zodiacal constellations 2017
Bottom line: As seen from Earth, the sun passes in front of the constellation Ophiuchus each year from about November 30 to December 18.
Birthday late November to middle December? Here’s your constellation
EarthSky astronomy kits are perfect for beginners. Order today from the EarthSky store
from EarthSky http://ift.tt/1l1yQbj
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