The breakthrough on June 21st has brought many positive developments.The amount of still present plasma toplet bombs is slowly but steadily decreasing, and the following scenario with toplets bombs detonating now seems extremely unlikely:https://www.da...
Tag: eye (page 1 of 17)
Tracy Kolenchuk, ContributorIt’s been almost 20 years since I met my first disappearing patient — a nurse in her early 40s, let’s call her Kate. Kate was diagnosed with breast cancer. As a nurse, she had seen the results of breast cancer treatments. She was terrified, and determined. She was not heading for surgery, nor chemotherapy, nor radiation.But Kate worked in a hospital. She worked with the doctors who diagnosed her cancer, and she worked with [...]
Vic Bishop, Staff WriterIt’s not too often that you see the mainstream be honest about what it is that makes themmainstream. Media is big money and has significant influence in our lives, and at present a mere 6 corporations own 90% of all the mediathat makes it into your mediasphere. Voices critical of this power structure are rarely heard on the big networks, however, sometimes the truth gets through.Take this eye-opening cartoon for example.In 1998, cartoonist Robert Sm [...]
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| This image shows a rare view of four quasars, indicated by white arrows, found together by astronomers using the Keck Observatory in Hawaii. The bright galactic nuclei are embedded in a giant nebula of cool, dense gas visible in the image as a blue haze. Hennawi & Arrigoni-Battaia, MPIA |
Excerpt from smithsonian.com
The odds of success would make a Vegas bookie sit up and take notice. But in a one-in-10 million chance, astronomers surveying the sky have found a group of four tightly packed quasars in one of the most distant parts of the universe. The rare grouping may be a nascent galaxy cluster, and its unusually cold cradle of gas could prompt a re-think of how we model the early universe.
Quasars are among the brightest objects known—according to NASA, each one gives off more energy than 100 mature galaxies combined. But quasars are found only in the far reaches of the universe and can't be seen with the naked eye. Because of the time it takes light to travel that far, detecting such distant objects is akin to seeing back in time, so astronomers think quasars are the seeds of young galaxies, powered by gases falling into the supermassive black holes at their cores. As matter falls inward and gets close to the speed of light, it emits radiation that we can pick up with telescopes.
The quasar phase doesn't last long, only about a thousandth of a galaxy's lifetime. After that, the brightness dies down as the inflow of matter slows, says study leader Joseph Hennawi, an astrophysicist at the Max Planck Institute in Germany. Seeing any two quasars close together while they are still bright is a chancy business, so his team wasn't sure what they'd find when they set out to survey quasars using the W.M. Keck Observatory in Hawaii. To their surprise, they quickly pinpointed four of them in close proximity, cosmically speaking. The quartet is huddled up in an area of sky less than 600,000 light-years across that sits about 10 billion light-years from Earth.
"The authors found it by investigating the environment of just 29 bright quasars," says Michele Trenti, a senior lecturer at the University of Melbourne's School of Physics. "So at face value it seems like winning the lottery with a handful of tickets."
That's not all that was strange about this quasar quartet. The foursome was found inside a cloud of cold, dark gas, and the team's observations suggest that similar clouds surround about 10 percent of the tens of thousands of known quasars. That's odd, because according to current theories, quasars in groups like this should be surrounded by hot plasma, or ionized gas, at a temperature of about 10 million degrees.
“What this means is that there is some physical process that the models aren’t capturing,” says Hennawi, whose team reports the discovery this week in Science.
The quasar phase doesn't last long, only about a thousandth of a galaxy's lifetime. After that, the brightness dies down as the inflow of matter slows, says study leader Joseph Hennawi, an astrophysicist at the Max Planck Institute in Germany. Seeing any two quasars close together while they are still bright is a chancy business, so his team wasn't sure what they'd find when they set out to survey quasars using the W.M. Keck Observatory in Hawaii. To their surprise, they quickly pinpointed four of them in close proximity, cosmically speaking. The quartet is huddled up in an area of sky less than 600,000 light-years across that sits about 10 billion light-years from Earth.
"The authors found it by investigating the environment of just 29 bright quasars," says Michele Trenti, a senior lecturer at the University of Melbourne's School of Physics. "So at face value it seems like winning the lottery with a handful of tickets."
That's not all that was strange about this quasar quartet. The foursome was found inside a cloud of cold, dark gas, and the team's observations suggest that similar clouds surround about 10 percent of the tens of thousands of known quasars. That's odd, because according to current theories, quasars in groups like this should be surrounded by hot plasma, or ionized gas, at a temperature of about 10 million degrees.
“What this means is that there is some physical process that the models aren’t capturing,” says Hennawi, whose team reports the discovery this week in Science.
Excerpt from huffingtonpost.com1. Notice the good -- any and all good you can find -- even if it is simply, "I am so glad to see your face this morning," or, "You've always had a knack for unique clothing combinations!" 2. If someone is grumpy,...
Excerpt from hubblesite.org
Scientists using NASA's Hubble Space Telescope have discovered that the immense halo of gas enveloping the Andromeda galaxy, our nearest massive galactic neighbor, is about six times larger and 1,000 times more massive than previously measured. The dark, nearly invisible halo stretches about a million light-years from its host galaxy, halfway to our own Milky Way galaxy. This finding promises to tell astronomers more about the evolution and structure of majestic giant spirals, one of the most common types of galaxies in the universe.
"Halos are the gaseous atmospheres of galaxies. The properties of these gaseous halos control the rate at which stars form in galaxies according to models of galaxy formation," explained the lead investigator, Nicolas Lehner of the University of Notre Dame, Indiana. The gargantuan halo is estimated to contain half the mass of the stars in the Andromeda galaxy itself, in the form of a hot, diffuse gas. If it could be viewed with the naked eye, the halo would be 100 times the diameter of the full Moon in the sky. This is equivalent to the patch of sky covered by two basketballs held at arm's length.
The Andromeda galaxy, also known as M31, lies 2.5 million light-years away and looks like a faint spindle, about 6 times the diameter of the full Moon. It is considered a near-twin to the Milky Way galaxy.
Because the gas in Andromeda's halo is dark, the team looked at bright background objects through the gas and observed how the light changed. This is a bit like looking at a glowing light at the bottom of a pool at night. The ideal background "lights" for such a study are quasars, which are very distant bright cores of active galaxies powered by black holes. The team used 18 quasars residing far behind Andromeda to probe how material is distributed well beyond the visible disk of the galaxy. Their findings were published in the May 10, 2015, edition of The Astrophysical Journal.
Earlier research from Hubble's Cosmic Origins Spectrograph (COS)-Halos program studied 44 distant galaxies and found halos like Andromeda's, but never before has such a massive halo been seen in a neighboring galaxy. Because the previously studied galaxies were much farther away, they appeared much smaller on the sky. Only one quasar could be detected behind each faraway galaxy, providing only one light anchor point to map their halo size and structure. With its close proximity to Earth and its correspondingly large footprint on the sky, Andromeda provides a far more extensive sampling of a lot of background quasars.
"As the light from the quasars travels toward Hubble, the halo's gas will absorb some of that light and make the quasar appear a little darker in just a very small wavelength range," explains co-investigator J. Christopher Howk, also of Notre Dame. "By measuring the dip in brightness in that range, we can tell how much halo gas from M31 there is between us and that quasar."
The scientists used Hubble's unique capability to study the ultraviolet light from the quasars. Ultraviolet light is absorbed by Earth's atmosphere, which makes it difficult to observe with a ground-based telescope. The team drew from about 5 years' worth of observations stored in the Hubble data archive to conduct this research. Many previous Hubble campaigns have used quasars to study gas much farther away than — but in the general direction of — Andromeda, so a treasure trove of data already existed.
But where did the giant halo come from? Large-scale simulations of galaxies suggest that the halo formed at the same time as the rest of Andromeda. The team also determined that it is enriched in elements much heavier than hydrogen and helium, and the only way to get these heavy elements is from exploding stars called supernovae. The supernovae erupt in Andromeda's star-filled disk and violently blow these heavier elements far out into space. Over Andromeda's lifetime, nearly half of all the heavy elements made by its stars have been expelled far beyond the galaxy's 200,000-light-year-diameter stellar disk.
What does this mean for our own galaxy? Because we live inside the Milky Way, scientists cannot determine whether or not such an equally massive and extended halo exists around our galaxy. It's a case of not being able to see the forest for the trees. If the Milky Way does possess a similarly huge halo, the two galaxies' halos may be nearly touching already and quiescently merging long before the two massive galaxies collide. Hubble observations indicate that the Andromeda and Milky Way galaxies will merge to form a giant elliptical galaxy beginning about 4 billion years from now.
by G. William DomhoffNOTE: WhoRulesAmerica.net is largely based on my book,Who Rules America?, first published in 1967 and now in its7th edition. This on-line document is presented as a summary of some of the main ideas in that book.Who has predominant power in the United States? The short answer, from 1776 to the present, is: Those who have the money -- or more specifically, who own income-producing land and businesses -- have the power. George Washington was one of the biggest landowner [...]
Excerpt from cnet.comEnceladus may have a warm ocean beneath its icy surface, but it may also be shooting through that crust in big sheets, perhaps filled with sea monkeys. We already know that Saturn's ...
Excerpt from huffingtonpost.comIntroductionWhy is it so hard to find ET? After 50 years of searching, the SETI project has so far found nothing. In the latest development, on April 14, 2015 Penn State researchers announced that after searching through...
Ethan Indigo Smith, ContributorThe recent “news” on the nuclear situation in Iran brings to light the madhouse of cards on which the postmodern world is built. Or rather, it would bring the madness to light if the major media outlets of the world were not bought up and sold out to the military industrial complex, and therefore completely misinformed on the actions and dangers of the nuclear experimentation industry.The story is not just about [...]
Excerpt from huffingtonpost.comIntroduction 65 years ago, in 1950, while having lunch with colleagues Edward Teller and Herbert York, Nobel physicist Enrico Fermi suddenly blurted out, "Where is everybody?" His question is now known as Fermi's p...
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The Hooker 100-inch reflecting telescope at the Mount Wilson Observatory, just outside Los Angeles. Edwin Hubble's chair, on an elevating platform, is visible at left. A view from this scope first told Hubble our galaxy isn't the only one. Courtesy of The Observatories of the Carnegie Institution for Science Collection at the Huntington Library, San Marino, Calif. |
Excerpt from hnpr.org
The Hubble Space Telescope this week celebrates 25 years in Earth's orbit. In that time the telescope has studied distant galaxies, star nurseries, planets in our solar system and planets orbiting other stars.
But, even with all that, you could argue that the astronomer for whom the telescope is named made even more important discoveries — with far less sophisticated equipment.
A young Edwin Hubble at Mount Wilson's 100-inch telescope circa 1922, ready to make history.
Edwin Hubble Papers/Courtesy of Huntington Library, San Marino, Calif.
In the 1920s, Edwin Hubble was working with the 100-inch Hooker telescope on Mount Wilson, just outside Los Angeles. At the time, it was the largest telescope in the world.
On a chilly evening, I climb up to the dome of that telescope with operator Nik Arkimovich and ask him to show me where Hubble would sit when he was using the telescope. Arkimovich points to a platform near the top of the telescope frame.
"He's got an eyepiece with crosshairs on it," Arkimovich explains. The telescope has gears and motors that let it track a star as it moves across the sky. "He's got a paddle that allows him to make minor adjustments. And his job is to keep the star in the crosshairs for maybe eight hours."
"It's certainly much, much easier today," says John Mulchaey, acting director of the observatories at Carnegie Institution of Science. "Now we sit in control rooms. The telescopes operate brilliantly on their own, so we don't have to worry about tracking and things like this."
The headquarters of the Carnegie observatories is at the foot of Mount Wilson, in the city of Pasadena. It's where Hubble worked during the day.
A century's worth of plates are stored here in the basement. Mulchaey opens a large steel door and ushers me into a room filled with dozens of file cabinets.
"Why don't we go take a look at Hubble's famous Andromeda plates," Mulchaey suggests.
The plates are famous for a reason: They completely changed our view of the universe. Mulchaey points to a plate mounted on a light stand.
"This is a rare treat for you," he says. "This plate doesn't see the light of day very often."
This glass side of a photographic plate shows where Hubble marked novas. The red VAR! in the upper right corner marks his discovery of the first Cepheid variable star — a star that told him the Andromeda galaxy isn't part of our Milky Way.
Courtesy of the Carnegie Observatories
The plate shows the spiral shape of the Andromeda galaxy. Hubble was looking for exploding stars called novas in Andromeda. Hubble marked these on the plate with the letter "N."
"The really interesting thing here," Mulchaey says, "is there's one with the N crossed out in red — and he's changed the N to VAR with an exclamation point."
Hubble had realized that what he was seeing wasn't a nova. VAR stands for a type of star known as a Cepheid variable. It's a kind of star that allows you to make an accurate determination of how far away something is. This Cepheid variable showed that the Andromeda galaxy isn't a part of our galaxy.
At the time, most people thought the Milky Way was it — the only galaxy in existence.
"And what this really shows is that the universe is much, much bigger than anybody realizes," Mulchaey says.
It was another blow to our human conceit that we are the center of the universe.
Hubble went on to use the Mount Wilson telescope to show the universe was expanding, a discovery so astonishing that Hubble had a hard time believing it himself.
If Hubble could make such important discoveries with century-old equipment, it makes you wonder what he might have turned up if he'd had a chance to use the space telescope that bears his name.
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