Tag: larger (page 2 of 11)

Hubble Finds Giant Halo Around the Andromeda Galaxy

May 11, 2015 / / 0 Comments





 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.

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Carl Sagan’s Solar Sail Goes On Test Flight On May 20: Why You Should Care

May 10, 2015 / / 0 Comments

Excerpt  from techtimes.comMany of the technologies that are in use today such as the airplane and the internet were once ideas that became reality and it appears that this still goes true with the innovations of the future. Take for instance ...

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The Class-Domination Theory of Power

May 9, 2015 / / 0 Comments

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 [...]

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Say NO to Tiny Houses and Big Bullsh… ~ Greg Giles

May 7, 2015 / / 0 Comments

Living the 'New' American DreamIn the days and on into the years ahead, you will not be able to get through a day without being subjected to an array of media articles, television shows, and all types of advertising for tiny houses, an alleged organi...

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The sun unleashes its biggest flare of the year

May 7, 2015 / / 0 Comments




Excerpt from dailytimes.com.pk

The sun has unleashed its most powerful flare of the year causing radio blackouts throughout the Pacific region.

The enormous X-class solar flare peaked at 6:11pm ET yesterday from a sunspot called Active Region 2339 (AR2339).

Solar flares are powerful bursts of radiation that, when intense enough, can disturb the atmosphere in the layer where GPS and communications signals travel - and scientists say they could get more powerful in the future.

This latest flare is classified as an X2.7. X-class denotes the most intense flares, while the number provides more information about its strength.

Despite the recent radio blackouts, scientists say the flare is unlikely to cause any further major issues here on Earth.

‘Given the impulsive nature of this event, as well as the source location on the eastern limb of the sun, we are not expecting a radiation storm at Earth,’ scientists with the U.S. Space Weather Prediction Center (SWPC) in Boulder, Colorado.

‘We will be on the lookout for new imagery from the Nasa Soho [Solar and Heliospheric Observatory] mission to determine if there was an associated coronal mass ejection (CME) with this event,’ they added.

‘Given the same logic above, however, we do not expect there to be one that would impact Earth.’

Yesterday Kazunari Shibata, an astrophysicist from Kyoto University in Japan, said the sun has the potential to unleash a flare of such a magnitude that it would be larger than anything humans have ever seen.

At the Space Weather Workshop in Colorado, Shibata said ‘superflares,’ that contain energy 1,000 times larger than what we have seen could be on their way.

He said there is evidence of this happening every 800 to 5,000 years on Earth,

Scientists say such a solar ‘super-storm’ would pose a ‘catastrophic’ and ‘long-lasting’ threat to life on Earth.

A superflare would induce huge surges of electrical currents in the ground and in overhead transmission lines, causing widespread power outages and severely damaging critical electrical components.

The largest ever solar super-storm on record occurred in 1859 and is known as the Carrington Event, named after the English astronomer Richard Carrington who spotted the preceding solar flare.

This massive CME released about 1022 kJ of energy - the equivalent to 10 billion Hiroshima bombs exploding at the same time - and hurled around a trillion kilos of charged particles towards the Earth at speeds of up to 3000 km/s.

However, its impact on the human population was relatively benign as our electronic infrastructure at the time amounted to no more than about 124,000 miles (200,000 km) of telegraph lines.

Nasa has also released incredible footage showing the sun unleashing a huge lick of plasma that increased the star’s visible hemisphere by almost half.

The solar filament, which exploded on April 28 and 29, was suspended above the sun due to strong magnetic fields that pushed outwards.

Solar astronomers around the world had their eyes on this unusually large filament and kept track as it erupted.

Nasa’s animation involves images taken from the orbiting Solar and Heliospheric Observatory using its Large Angle Spectrometric Coronagraph.

The diameter of the animation is about 30 million miles (45 million km) at the distance of the sun, or half of the diameter of the orbit of Mercury.

The white circle in the centre of the round disk represents the size of the sun, which is being blocked by the telescope in order to see the fainter material around it.

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6 Natural Solutions To Decontaminate Soil

May 2, 2015 / / 0 Comments

Marco Torres, Prevent DiseaseWith a progressively educated population becoming more aware of the inherent dangers of the conventional food supply, urban farming has become hugely popular. However, more people are also becoming aware of contaminated soil and how heavy metals pose potential risks to their food crops. As backyard gardening continues to explode in popularity, we must ask how contaminated is our soil?Many municipalities in many countries are embracing urban agri [...]

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IBM advances bring quantum computing closer to reality

April 29, 2015 / / 0 Comments



ibm research jerry chow
 
Research scientist Jerry Chow performs a quantum computing experiment at IBM's Thomas J. Watson Research Center in Yorktown Heights, N.Y. Jon Simon/IBM


Excerpt from computerworld.com
By Sharon Gaudin

IBM scientists say they have made two critical advances in an industrywide effort to build a practical quantum computer, shaving years off the time expected to have a working system.

"This is critical," said Jay Gambetta, IBM's manager of theory of quantum computing. "The field has got a lot more competitive. You could say the [quantum computing] race is just starting to begin… This is a small step on the journey but it's an important one."

Gambetta told Computerworld that IBM's scientists have created a square quantum bit circuit design, which could be scaled to much larger dimensions. This new two-dimensional design also helped the researchers figure out a way to detect and measure errors.
Quantum computing is a fragile process and can be easily thrown off by vibrations, light and temperature variations. Computer scientists doubt they'll ever get the error rate down to that in a classical computer.
Because of the complexity and sensitivity of quantum computing, scientists need to be able to detect errors, figure out where and why they're happening and prevent them from recurring.

IBM says its advancement takes the first step in that process.
"It tells us what errors are happening," Gambetta said. "As you make the square [circuit design] bigger, you'll get more information so you can see where the error was and you can correct for it. We're showing now that we have the ability to detect, and we're working toward the next step, which would allow you to see where and why the problem is happening so you can stop it from happening."

Quantum computing is widely thought to be the next great step in the field of computing, potentially surpassing classical supercomputers in large-scale, complex calculations. 

Quantum computing would be used to cull big data, searching for patterns. It's hoped that these computers will take on questions that would lead to finding cures for cancer or discovering distant planets – jobs that might take today's supercomputers hundreds of years to calculate.

IBM's announcement is significant in the worlds of both computing and physics, where quantum theory first found a foothold.

Quantum computing, still a rather mysterious technology, combines both computing and quantum mechanics, which is one of the most complex, and baffling, areas of physics. This branch of physics evolved out of an effort to explain things that traditional physics is unable to.

With quantum mechanics, something can be in two states at the same time. It can be simultaneously positive and negative, which isn't possible in the world as we commonly know it. 

For instance, each bit, also known as a qubit, in a quantum machine can be a one and a zero at the same time. When a qubit is built, it can't be predicted whether it will be a one or a zero. A qubit has the possibility of being positive in one calculation and negative in another. Each qubit changes based on its interaction with other qubits.

Because of all of these possibilities, quantum computers don't work like classical computers, which are linear in their calculations. A classical computer performs one step and then another. A quantum machine can calculate all of the possibilities at one time, dramatically speeding up the calculation.

However, that speed will be irrelevant if users can't be sure that the calculations are accurate.

That's where IBM's advances come into play.

"This is absolutely key," said Jim Tully, an analyst with Gartner. "You do the computation but then you need to read the results and know they're accurate. If you can't do that, it's kind of meaningless. Without being able to detect errors, they have no way of knowing if the calculations have any validity."

If scientists can first detect and then correct these errors, it's a major step in the right direction to building a working quantum computing system capable of doing enormous calculations. 

"Quantum computing is a hard concept for most to understand, but it holds great promise," said Dan Olds, an analyst with The Gabriel Consulting Group. "If we can tame it, it can compute certain problems orders of magnitude more quickly than existing computers. The more organizations that are working on unlocking the potential of quantum computing, the better. It means that we'll see something real that much sooner."
However, there's still debate over whether a quantum computer already exists.

A year ago, D-Wave Systems Inc. announced that it had built a quantum system, and that NASA, Google and Lockheed Martin had been testing them.

Many in the computer and physics communities doubt that D-Wave has built a real quantum computer. Vern Brownell, CEO of the company, avows that they have.

"I think that quantum computing shows promise, but it's going to be quite a while before we see systems for sale," said Olds.
IBM's Gambetta declined to speculate on whether D-Wave has built a quantum computing but said the industry is still years away from building a viable quantum system.

"Quantum computing could be potentially transformative, enabling us to solve problems that are impossible or impractical to solve today," said Arvind Krishna, senior vice president and director of IBM Research, in a statement.

IBM's research was published in Wednesday's issue of the journal Nature Communications.

quantum computing infographics ibm

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This revolutionary discovery could help scientists see black holes for the first time

April 29, 2015 / / 0 Comments


supermassive black hole
Artist's concept of the black hole.
Excerpt from finance.yahoo.com
Of all the bizarre quirks of nature, supermassive black holes are some of the most mysterious because they're completely invisible.
But that could soon change.
Black holes are deep wells in the fabric of space-time that eternally trap anything that dares too close, and supermassive black holes have the deepest wells of all. These hollows are generated by extremely dense objects thousands to billions of times more massive than our sun.
Not even light can escape black holes, which means they're invisible to any of the instruments astrophysicists currently use. Although they don't emit light, black holes will, under the right conditions, emit large amounts of gravitational waves — ripples in spacetime that propagate through the universe like ripples across a pond's surface.
And although no one has ever detected a gravitational wave, there are a handful of instruments around the world waiting to catch one.

Game-changing gravitational waves



.
black hole
This illustration shows two spiral galaxies - each with supermassive black holes at their center - as they are about to collide. 

Albert Einstein first predicted the existence of gravitational waves in 1916. According to his theory of general relativity, black holes will emit these waves when they accelerate to high speeds, which happens when two black holes encounter one another in the universe.  

As two galaxies collide, for example, the supermassive black holes at their centers will also collide. But first, they enter into a deadly cosmic dance where the smaller black hole spirals into the larger black hole, moving increasingly faster as it inches toward it's inevitable doom. As it accelerates, it emits gravitational waves.
Astrophysicists are out to observe these waves generated by two merging black holes with instruments like the Laser Interferometer Gravitational-Wave Observatory.
"The detection of gravitational waves would be a game changer for astronomers in the field," Clifford Will, a distinguished profess of physics at the University of Florida who studied under famed astrophysicist Kip Thorne told Business Insider. "We would be able to test aspects of general relativity that have not been tested."
Because these waves have never been detected, astrophysicists are still trying to figure out how to find them. To do this, they build computer simulations to predict what kinds of gravitational waves a black hole merger will produce. 

Learn by listening

In the simulation below, made by Steve Drasco at California Polytechnic State University (also known as Cal Poly), a black hole gets consumed by a supermassive black hole about 30,000 times as heavy.
You'll want to turn up the volume.
What you're seeing and hearing are two different things.
The black lines you're seeing are the orbits of the tiny black hole traced out as it falls into the supermassive black hole. What you're hearing are gravitational waves.
"The motion makes gravitational waves, and you are hearing the waves," Drasco wrote in a blog post describing his work.
Of course, there is no real sound in space, so if you somehow managed to encounter this rare cataclysmic event, you would not likely hear anything. However, what Drasco has done will help astrophysicists track down these illusive waves.

Just a little fine tuning 

Gravitational waves are similar to radio waves in that both have specific frequencies. On the radio, for example, the number corresponding to the station you're listening to represents the frequency at which that station transmits.


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gwaves
3D visualization of gravitational waves produced by 2 orbiting black holes. Right now, astrophysicists only have an idea of what frequencies two merging black holes transmit because they’re rare and hard to find. In fact, the first ever detection of an event of this kind was only announced this month. 

Therefore, astrophysicists are basically toying with their instruments like you sometimes toy with your radio to find the right station, except they don’t know what station will give them the signal they’re looking for.
What Drasco has done in his simulation is estimate the frequency at which an event like this would produce and then see how that frequency changes, so astrophysicists have a better idea of how to fine tune their instruments to search for these waves.
Detecting gravitational waves would revolutionize the field of astronomy because it would give observers an entirely new way to see the universe. Armed with this new tool, they will be able to test general relativity in ways never before made possible.

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Guiding Our Search for Life on Other Earths

April 13, 2015 / / 0 Comments


The James Webb Telescope


Excerpt from space.com

 A telescope will soon allow astronomers to probe the atmosphere of Earthlike exoplanets for signs of life. To prepare, astronomer Lisa Kaltenegger and her team are modeling the atmospheric fingerprints for hundreds of potential alien worlds. Here's how:
The James Webb Space Telescope, set to launch in 2018, will usher a new era in our search for life beyond Earth. With its 6.5-meter mirror, the long-awaited successor to Hubble will be large enough to detect potential biosignatures in the atmosphere of Earthlike planets orbiting nearby stars.
And we may soon find a treasure-trove of such worlds. The forthcoming exoplanet hunter TESS (Transiting Exoplanet Survey Satellite), set to launch in 2017, will scout the entire sky for planetary systems close to ours. (The current Kepler mission focuses on more distant stars, between 600 and 3,000 light-years from Earth.) 

Astronomer Lisa Kaltenegger




While TESS will allow for the brief detection of new planets, the larger James Webb will follow up on select candidates and provide clues about their atmospheric composition. But the work will be difficult and require a lot of telescope time.
"We're expecting to find thousands of new planets with TESS, so we'll need to select our best targets for follow-up study with the Webb telescope," says Lisa Kaltenegger, an astronomer at Cornell University and co-investigator on the TESS team.
To prepare, Kaltenegger and her team at Cornell's Institute for Pale Blue Dots are building a database of atmospheric fingerprints for hundreds of potential alien worlds. The models will then be used as "ID cards" to guide the study of exoplanet atmospheres with the Webb and other future large telescopes.
Kaltenegger described her approach in a talk for the NASA Astrobiology Institute's Director Seminar Series last December.
"For the first time in human history, we have the technology to find and characterize other worlds," she says. "And there's a lot to learn."

Detecting life from space  

In its 1990 flyby of Earth, the Galileo spacecraft took a spectrum of sunlight filtered through our planet's atmosphere. In a 1993 paper in the journal Nature, astronomer Carl Sagan analyzed that data and found a large amount of oxygen together with methane — a telltale sign of life on Earth. These observations established a control experiment for the search of extraterrestrial life by modern spacecraft.
"The spectrum of a planet is like a chemical fingerprint," Kaltenegger says. "This gives us the key to explore alien worlds light years away."
Current telescopes have picked up the spectra of giant, Jupiter-like exoplanets. But the telescopes are not large enough to do so for smaller, Earth-like worlds. The James Webb telescope will be our first shot at studying the atmospheres of these potentially habitable worlds.
Some forthcoming ground-based telescopes — including the Giant Magellan Telescope (GMT), planned for completion in 2020, and the European Extremely Large Telescope (E-ELT), scheduled for first light in 2024 — may also be able to contribute to that task. [The Largest Telescopes on Earth: How They Compare]
And with the expected discovery by TESS of thousands of nearby exoplanets, the James Webb and other large telescopes will have plenty of potential targets to study. Another forthcoming planet hunter, the Planetary Transits and Oscillations of stars (PLATO), a planned European Space Agency mission scheduled for launch around 2022-2024, will contribute even more candidates.
However, observation time for follow-up studies will be costly and limited.
"It will take hundreds of hours of observation to see atmospheric signatures with the Webb telescope," Kaltenegger says. "So we'll have to pick our targets carefully."

Giant Magellan Telescope
Set to see its first light in 2021, The Giant Magellan Telescope will be the world’s largest telescope.

Getting a head start

To guide that process, Kaltenegger and her team are putting together a database of atmospheric fingerprints of potential alien worlds. "The models are tools that can teach us how to observe and help us prioritize targets," she says.
To start, they have modeled the chemical fingerprint of Earth over geological time. Our planet's atmosphere has evolved over time, with different life forms producing and consuming various gases. These models may give astronomers some insight into a planet's evolutionary stage.
Other models take into consideration the effects of a host of factors on the chemical signatures — including water, clouds, atmospheric thickness, geological cycles, brightness of the parent star, and even the presence of different extremophiles.
"It's important to do this wide range of modeling right now," Kaltenegger said, "so we're not too startled if we detect something unexpected. A wide parameter space can allow us to figure out if we might have a combination of these environments."
She added: "It can also help us refine our modeling as fast as possible, and decide if more measurements are needed while the telescope is still in space. It's basically a stepping-stone, so we don't have to wait until we get our first measurements to understand what we are seeing. Still, we'll likely find things we never thought about in the first place."
 

A new research center

The spectral database is one of the main projects undertaken at the Institute for Pale Blue Dots, a new interdisciplinary research center founded in 2014 by Kaltenegger. The official inauguration will be held on May 9, 2015.
"The crux of the institute is the characterization of rocky, Earth-like planets in the habitable zone of nearby stars," Kaltenergger said. "It's a very interdisciplinary effort with people from astronomy, geology, atmospheric modeling, and hopefully biology."
She added: "One of the goal is to better understand what makes a planet a life-friendly habitat, and how we can detect that from light years away. We're on the verge of discovering other pale blue dots. And with Sagan's legacy, Cornell University is a really great home for an institute like that."

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Aliens Might Weigh As Much As Polar Bears And Be Taller Than The Tallest Man Who Ever Lived

April 11, 2015 / / 0 Comments





Excerpt from huffingtonpost.com

No one really knows whether we're alone or if the universe is brimming with brainy extraterrestrials. But that hasn't stopped scientists from trying to figure out what form intelligent aliens might take. 

And as University of Barcelona cosmologist Dr. Fergus Simpson argues in a new paper, most intelligent alien species would likely exceed 300 kilograms (661 pounds)--with the median body mass "similar to that of a polar bear."

If such a being had human proportions, Simpson told The Huffington Post in an email, it would be taller than Robert Wadlow, who at 8 feet, 11 inches is believed to have been the tallest human who ever lived.

robert wadlowRobert Wadlow (1918-1940), the tallest man who ever lived.


Simpson's paper, which is posted on the online research repository arXiv.org, is chockablock with formidable-looking mathematical equations. But as he explained in the email, his starting point was to consider the relationship between the number of individuals in a population on Earth and the body mass of those individuals:
"Ants easily outnumber us because they are small. Our larger bodies require a much greater energy supply from the local resources, so it would be impossible for us to match the ant population. Now apply this concept to intelligent life across the universe. On average, we should expect physically larger species to have fewer individuals than the smaller species. And, just like with countries, we should expect to be in one of the bigger populations. In other words, we are much more likely to find ourselves to be the ants among intelligent species."

Or, as Newsweek explained Simpson's argument, there are probably more planets with relatively small animals than planets with relatively large animals. It makes sense to assume that Earth is in the former category, so we can assume that humans are probably among the smaller intelligent beings.

What do other scientists make of Simpson's paper?

“I think the average size calculation is reasonable,” Dr. Duncan Forgan, an astrobiologist at the University of St. Andrews in Scotland who wasn't involved in the research, told Newsweek.
But to Dr. Seth Shostak, senior astronomer at the SETI Institute in Mountain View, Calif., the argument is suspect.

"There is an assumption here that intelligence can come in all (reasonable) sizes, and does so with more or less equal likelihood," Shostak told The Huffington Post in an email. "That may be true, but on Earth bigger has not always been better, at least in the brains department. Dolphins have higher IQs than whales, and crows are smarter than eagles. Octopuses are cleverer than giant squids, and obviously we’re smarter than polar bears."

Ultimately, Shostak said, we can’t know whether "little green men are actually big green men" before we actually make contact.
Until then!

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An Alien Radio Beacon? Possibly Not This Time

April 5, 2015 / / 0 Comments



An Alien Radio Beacon? Possibly Not This Time.

Excerpt from postpioneer.com


For practically a decade, astronomers have puzzled over strong bursts of radio energy that appear to be hailing from billions of light years away. Recently, we received reports of a new wrinkle to this mystery: The bursts seem to comply with a mathematical...

For practically a decade, astronomers have puzzled over strong bursts of radio energy that appear to be hailing from billions of light years away. Recently, we received reports of a new wrinkle to this mystery: The bursts seem to comply with a mathematical pattern, one that does not line up with something we know about cosmic physics.

And, of course, when we hear “mathematical pattern,” “radio transmission,” and “outer space,” all strung collectively, we straight away jump to our preferred explanation—aliens! (Or, you know, a decaying pulsar star, an unmapped spy satellite, or a cell telephone tower.)

It’s also probable that the pattern doesn’t basically exist.

Because 2007, telescopes have picked up almost a dozen so-known as “fast radio bursts,” pulses that last for mere milliseconds, but erupt with as a great deal power as the sun releases in a month. Where could they be coming from? To come across out, a group of researchers took advantage of a basic principle: That higher frequency radio waves encounter less interference as they traverse space, and are detected by our telescopes earlier than reduce frequency waves. The time delay, or “dispersion measure”, in between larger and reduce frequency radio waves from the very same pulse event can be applied to figure out the distance those waves traveled.

Here’s where things got weird. When researchers calculated the dispersion distance for each and every of eleven rapid radio bursts, they identified that every distance is an integer many of a single number: 187.5. When plotted on a graph, as the researchers show us in Figure 1 of their paper, the points type a striking pattern.

A single explanation is that the bursts are coming from distinctive sources, all at on a regular basis spaced intervals from the Earth, billions of light years away. They could also be brought on by a smaller cosmic object a lot closer to residence, such as a pulsar star, behaving according to some sort of physics we don’t yet understand. And then there’s the possibility that aliens are trying to communicate, by blasting simple numeric patterns into space.

But no matter how you slice it, eleven data points is a tiny sample set to draw any meaningful conclusions from. A handful of deviant observations could bring about the complete pattern to unravel.

And that is precisely what seems to be happening. As Nadia Drake reports for National Geographic, newer observations, not integrated in the most up-to-date scientific report or other well known media articles, don’t fit:

“There are 5 quickly radio bursts to be reported,” says Michael Kramer of Germany’s Max Planck Institute for Radioastronomy. “They do not fit the pattern.”
Rather of aliens, unexpected astrophysics, or even Earthly interference, the mysterious mathematical pattern is probably an artifact produced by a little sample size, Ransom says. When working with a limited quantity of data – say, a population of 11 quickly radio bursts – it’s straightforward to draw lines that connect the dots. Usually, on the other hand, these lines disappear when much more dots are added.
“My prediction is that this pattern will be washed out quite immediately after a lot more fast radio bursts are located,” says West Virginia University’s Duncan Lorimer, who reported the very first burst in 2007. “It’s a great instance of how apparently considerable final results can be identified in sparse information sets.”

That is a bit of a bummer, but nevertheless, these radio bursts are fascinating, and what could be causing them remains as a lot of a mystery as ever. It could even nonetheless be aliens, if not an alien beacon. As SETI Institute Director Seth Shostak told me in an e mail:

“If it is a signal, nicely, it is surely NOT a message — except perhaps to say ‘here we are’. There’s not actual bandwidth to it, which suggests these speedy radio bursts can not encode several bits. But there are so many other possibilities, I feel that automatically attributing one thing in the sky that we don’t (at very first) understand to the operate of aliens is … premature!”

If there’s 1 point that is clear in this whole organization, it is that we’ve nonetheless got plenty to discover about the patterns woven into the universe around us.

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Why Luke Skywalker’s binary sunset may be real after all

March 30, 2015 / / 0 Comments






Excerpt from csmonitor.com

Researchers have found Jupiter-scale gas giants orbiting binary stars and estimate that Earth-like planets orbiting binary stars could be as numerous as rocky planets orbiting single-star systems.


For all the sci-fi charm of watching a pair of suns sink below a distant horizon on a planet in a galaxy far, far away, conventional wisdom has held that binary-star systems can't host Earth-scale rocky planets.

As the two stars orbit each other like square-dance partners swinging arm in arm, regular variations in their gravitational tug would disrupt planet formation at the relatively close distances where rocky planets tend to appear.

Not so fast, say two astrophysicists. They argue that only are Tatooine-like planets likely to be out there. They could be as numerous as rocky planets orbiting single-star systems – which is to say, there could be large number of them.

Building rocky planets in a binary system not only is possible, it's "not even that hard," says Scott Kenyon, an astrophysicist at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., who along with University of Utah astrophysicist Benjamin Bromley performed the calculations.
Researchers have found Jupiter-scale gas giants orbiting binary stars and have estimated that such gas giants are likely to be as common in binary systems as they are in systems with a single star.
"If that's true, then Earth-like planets around binaries are just as common as Earth-like planets around single stars," Dr. Kenyon says. "If they're not common, that tells you something about how they form or how they interact with the star over billions of years."

The modeling study grew out of work the two researchers were undertaking to figure out how the dwarf planet Pluto and its largest moon Charon manage to share space with four smaller moons that orbit the two larger objects. 

Pluto and Charon form a binary system that early in its history saw the two objects graze each other to generate a ring of dust that would become the additional moons.

The gravity the surrounding dust felt as Pluto and Charon swung about their shared center of mass would vary with clock-like precision.

Conventional wisdom held that this variable tug would trigger collisions at speeds too fast to allow the dust and larger chunks to merge into ever larger objects.

Kenyon and Dr. Bromley found that, in fact, the velocities would be smaller than people thought – no greater than the speeds would be around a single central object, where velocities are slow enough to allow the debris to bump gently and merge to build ever-larger objects.

They recognized that binary stars hosting planets are essentially scaled-up versions of the Pluto-Charon system. So they applied their calculations to a hypothetical binary star system with a circumstellar disk of dust and debris.

"The modest jostling in these orbits is the same modest jostling you'd get around a single star," Kenyon says, allowing rocky inner planets to form.

As for the Jupiter- or Neptune-scale planets found around binary stars, they would have formed farther out and migrated in over time, the researchers say, since there is too little material within the inner reaches of a circumstellar disk to build giant planets.

The duo's calculations imply that as more planets are discovered orbiting binary stars, a rising number of Tatooines will be among them. 

Tatooine "was science fiction," Kenyon says. But "it's not so far from science reality."

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The Story of Human Evolution Now Challenged

March 29, 2015 / / 0 Comments



Story of Human Evolution Challenged


Excerpt from newhistorian.com

The history of the evolution of early humans has been challenged.
Until now, one of the most dominant theories about our evolution claimed that our genus, Homo, had evolved from smaller early humans becoming taller, heavier and longer-legged. This process eventually resulted in Homo erectus, which was able to migrate out of Africa and colonise Eurasia.

Whilst we know that small-bodied H. erectus, averaging less than five feet tall and weighing under 50 kilograms, were living in southern Europe by 1.77 million years ago, the origin of the larger body size associated with modern humans has been elusive.

The paucity of knowledge about the origins of larger members of the Homo genus is primarily a result of a lack of evidence. Previous estimates of body size had been based on well-preserved specimens which were easy to assign a species to. Since these samples are rare and disparate in terms of both space and time, little is known about geographical and chronological variation in the body sizes of the early Homo.

A joint study between the Universities of Cambridge and Tübingen has shown that increases in body size occurred thousands of years after H. erectus left Africa; this growth in Homo body sizes primarily took place in the Koobi Fora region in modern Kenya.

“The evolution of larger bodies and longer legs can thus no longer be assumed to be the main driving factor behind the earliest excursions of our genus to Eurasia,” said Manuel Will, co-author of the study which has been published in the Journal of Human Evolution.

By using tiny fragments of fossil, the team were able to estimate our earliest ancestors’ height and body mass. Their findings, rather surprisingly, indicate a huge diversity in body size; this is particularly surprising as the wide variation we see in humans today was thought to be a relatively recent development.

“If someone asked you ‘are modern humans 6 foot tall and 70kg?’ you’d say ‘well some are, but many people aren’t,’ and what we’re starting to show is that this diversification happened really early in human evolution,” said Dr Jay Stock, co-author of the study.

Stock and Will are the first scientists in 20 years to compare the body size of humans from between 2.5 and 1.5 million years ago. They are also the first to use fragmentary fossils – many as small as toes, none longer than 5cm – to estimate body sizes.

By comparing measurements of fossils from sites in Kenya, Tanzania, South Africa and Georgia, the researchers have revealed substantial regional variation in the size of early humans. Groups who lived in South African caves, for example, were 4.8 feet tall on average. Some of the skeletons found in Kenya’s Koobi Fora region would have stood nearly 6 feet tall, a height comparable to the average height of modern British males.
“Basically every textbook on human evolution gives the perspective that one lineage of humans evolved larger bodies before spreading beyond Africa. But the evidence for this story about our origins and the dispersal out of Africa just no longer really fits,” said Stock.

It appears that Stock and Will have rewritten the history of the development of early humans; diversity has deep roots amongst the Homo genus.

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