Tag: field (page 6 of 26)

This Alien Color Catalog May Help Us Spot Life on Other Planets






Excerpt from smithsonianmag.com


In the hunt for alien life, our first glimpse of extraterrestrials may be in the rainbow of colors seen coming from the surface of an exoplanet.

That's the deceptively simple idea behind a study led by Siddharth Hegde at the Max Planck Institute for Astronomy in Germany. Seen from light-years away, plants on Earth give our planet a distinctive hue in the near-infrared, a phenomenon called red edge. That's because the chlorophyll in plants absorbs most visible light waves but starts to become transparent to wavelengths on the redder end of the spectrum. An extraterrestrial looking at Earth through a telescope could match this reflected color with the presence of oxygen in our atmosphere and conclude there is life here.


exoplanets palette
Eight of the 137 microorganism samples used to measure biosignatures for the catalog of reflection signatures of Earth life forms. In each panel, the top is a regular photograph of the sample and the bottom is a micrograph, a version of the top image zoomed-in 400 times.



Plants, though, have only been around for 500 million years—a relative blip in our planet's 4.6-billion-year history. Microbes dominated the scene for some 2.5 billion years in the past, and some studies suggest they will rule the Earth again for much of its future. So Hegde and his team gathered 137 species of microorganisms that all have different pigments and that reflect light in specific ways. By building up a library of the microbes' reflectance spectra—the types of colors those microscopic critters reflect from a distance—scientists examining the light from habitable exoplanets can have a plethora of possible signals to search for, the team argues this week in the Proceedings of the National Academy of Sciences.

"No one had looked at the wide range of diverse life on Earth and asked how we could potentially spot such life on other planets, and include life from extreme environments on Earth that could be the 'norm' on other planets," Lisa Kaltenegger, a co-author on the study, says via email. "You can use it to model an Earth that is different and has different widespread biota and look how it would appear to our telescopes."

To make sure they got enough diversity, the researchers looked at temperate-dwelling microbes as well as creatures that live in extreme environments like deserts, mineral springs, hydrothermal vents or volcanically active areas.

While it might seem that alien life could take a huge variety of forms—for instance, something like the silicon-based Horta from Star Trek—it's possible to narrow things down if we restrict the search to life as we know it. First, any life-form that is carbon-based and uses water as a solvent isn't going to like the short wavelengths of light far in the ultraviolet, because this high-energy UV can damage organic molecules. At the other end of the spectrum, any molecule that alien plants (or their analogues) use to photosynthesize won't be picking up light that's too far into the infrared, because there's not enough energy at those longer wavelengths.

In addition, far-infrared light is hard to see through an Earth-like atmosphere because the gases block a lot of these waves, and whatever heat the planet emits will drown out any signal from surface life. That means the researchers restricted their library to the reflected colors we can see when looking at wavelengths in the visible part of the spectrum, the longest wavelength UV and short-wave infrared.

The library won't be much use if we can't see the planets' surfaces in the first place, and that's where the next generation of telescopes comes in, Kaltenegger says. The James Webb Space Telescope, scheduled for launch in 2018, should be able to see the spectra of relatively small exoplanet atmospheres and help scientists work out their chemical compositions, but it won't be able to see any reflected spectra from material at the surface. Luckily, there are other planned telescopes that should be able to do the job. The European Extremely Large Telescope, a 40-meter instrument in Chile, will be complete by 2022. And NASA's Wide Field Infrared Survey Telescope, which is funded and in its design stages, should be up and running by the mid-2020s.

Another issue is whether natural geologic or chemical processes could look like life and create a false signal. So far the pigments from life-forms look a lot different from those reflected by minerals, but the team hasn't examined all the possibilities either, says Kaltenegger. They hope to do more testing in the future as they build up the digital library, which is now online and free for anyone to explore at biosignatures.astro.cornell.edu.

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Scientists: Enceladus may have warm water ocean with ingredients for life


Enceladus ocean
This artist's impression of the interior of Saturn's moon Enceladus shows that interactions between hot water and rock occur at the floor of the subsurface ocean -- the type of environment that might be friendly to life, scientists say. (NASA/JPL-Caltech)



Excerpt from latimes.com

Scientists say they’ve discovered evidence of a watery ocean with warm spots hiding beneath the surface of Saturn’s icy moon Enceladus. The findings, described in the journal Nature, are the first signs of hydrothermal activity on another world outside of Earth – and raise the chances that Enceladus has the potential to host microbial life.

Scientists have wondered about what lies within Enceladus at least since NASA’s Cassini spacecraft caught the moon spewing salty water vapor out from cracks in its frozen surface. Last year, a study of its gravitational field hinted at a 10-kilometer-thick regional ocean around the south pole lying under an ice crust some 30 to 40 kilometers deep.

Another hint also emerged about a decade ago, when Cassini discovered tiny dust particles escaping Saturn’s system that were nanometer-sized and rich in silicon.

“It’s a peculiar thing to find particles enriched with silicon,” said lead author Hsiang-Wen Hsu, a planetary scientist at the University of Colorado, Boulder. In Saturn’s moons and among its rings, water ice dominates, so these odd particles clearly stood out.

The scientists traced these particles’ origin to Saturn’s E-ring, which lies between the orbits of the moons Mimas and Titan and whose icy particles are known to come from Enceladus. So Hsu and colleagues studied the grains to understand what was going on inside the gas giant’s frigid satellite.   
Rather than coming in a range of sizes, these particles were all uniformly tiny – just a few nanometers across. Studying the spectra of these grains, the scientists found that they were made of silicon dioxide, or silica. That’s not common in space, but it’s easily found on Earth because it’s a product of water interacting with rock. 

Knowing how silica interacts in given conditions such as temperature, salinity and alkalinity, the scientists could work backward to determine what kind of environment creates these unusual particles.

A scientist could do the same thing with a cup of warm coffee, Hsu said.

“You put in the sugar and as the coffee gets cold, if you know the relation of the solubility of sugar as a function of temperature, you will know how hot your coffee was,” Hsu said. “And applying this to Enceladus’s ocean, we can derive a minimum [temperature] required to form these particles.”

The scientists then ran experiments in the lab to determine how such silica particles came to be. With the particles’ particular makeup and size distribution, they could only have formed under very specific circumstances, the study authors found, determining that the silica particles must have formed in water that had less than 4% salinity and that was slightly alkaline (with a pH of about 8.5 to 10.5) and at temperatures of at least 90 degrees Celsius (roughly 190 degrees Fahrenheit).

The heat was likely being generated in part by tidal forces as Saturn’s gravity kneads its icy moon. (The tidal forces are also probably what open the cracks in its surface that vent the water vapor into space.)
Somewhere inside the icy body, there was hydrothermal activity – salty warm water interacting with rocks. It’s the kind of environment that, on Earth, is very friendly to life.  

“It’s kind of obvious, the connection between hydrothermal interactions and finding life,” Hsu said. “These hydrothermal activities will provide the basic activities to sustain life: the water, the energy source and of course the nutrients that water can leach from the rocks.”

Enceladus, Hsu said, is now likely the “second-top object for astrobiology interest” – the first being Jupiter’s icy moon and fellow water-world, Europa.
This activity is in all likelihood going on right now, Hsu said – over time, these tiny grains should glom together into larger and larger particles, and because they haven’t yet, they must have been recently expelled from Enceladus, within the last few months or few years at most.

Gabriel Tobie of the University of Nantes in France, who was not involved in the research, compared the conditions that created these silica particles to a hydrothermal field in the Atlantic Ocean known as Lost City.

“Because it is relatively cold, Lost City has been posited as a potential analogue of hydrothermal systems in active icy moons. The current findings confirm this,” Tobie wrote in a commentary on the paper. “What is more, alkaline hydrothermal vents might have been the birthplace of the first living organisms on the early Earth, and so the discovery of similar environments on Enceladus opens fresh perspectives on the search for life elsewhere in the Solar System.”

However, Hsu pointed out, it’s not enough to have the right conditions for life – they have to have been around for long enough that life would have a fighting chance to emerge.

“The other factor that is also very important is the time.… For Enceladus, we don’t know how long this activity has been or how stable it is,” Hsu said. “And so that’s a big uncertainty here.”

One way to get at this question? Send another mission to Enceladus, Tobie said.

“Cassini will fly through the moon’s plume again later this year,” he wrote, “but only future missions that can undertake improved in situ investigations, and possibly even return samples to Earth, will be able to confirm Enceladus’ astrobiological potential and fully reveal the secrets of its hot springs. ”

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Japan comes closer to beaming solar power from SPACE: Mitsubishi makes breakthrough in sending energy wirelessly



Japanese scientists say they have successfully transmitted energy wirelessly in a breakthrough for future solar space power systems. While the distance was relatively small, the technology could someday pave the way for mankind to tap the vast amount of solar energy available in space and use it here on Earth
Japanese scientists say they have successfully transmitted energy wirelessly in a breakthrough for future solar space power systems. While the distance was relatively small, the technology could someday pave the way for mankind to tap the vast amount of solar energy available in space and use it here on Earth


  • Excerpt from dailymail.co.uk
  • By Ellie Zolfagharifard
  • Microwaves delivered 1.8 kw of power - enough to run an electric kettle
  • Power was sent through the air with to a receiver 170ft (55 metres) away
  • Technology may someday help tap vast solar energy available in space
  • Jaxa's plan is to eventually have sunlight-gathering panels and antennae set up about 22,300 miles (36,000km) from the Earth


Japanese scientists have successfully transmitted energy wirelessly in a breakthrough that could pave the way for space-based solar power systems.

Mitsubishi researchers used microwaves to deliver 1.8 kilowatts of power - enough to run an electric kettle - through the air with pinpoint accuracy to a receiver 170ft (55 metres) away.

While the distance was relatively small, the technology could someday pave the way for mankind to tap the vast amount of solar energy available in space and use it here on Earth.

'This was the first time anyone has managed to send a high output of nearly two kilowatts of electric power via microwaves to a small target, using a delicate directivity control device,' said a spokesman for the Japan Aerospace Exploration Agency (Jaxa) said.

The test, which took place at Kobe Shipyard & Machinery Works in Nagoya, Japan, will help Jaxa devise its long-awaited space solar power system.

Solar power generation in space has many advantages over its Earth-based cousin, notably the permanent availability of energy, regardless of weather or time of day.

While man-made satellites, such as the International Space Station, have long since been able to use the solar energy that washes over them from the sun, getting that power down to Earth where people can use it has been the thing of science fiction.

The test, which took place at Kobe Shipyard & Machinery Works in Nagoya, Japan, will help Jaxa devise its long-awaited space solar power system. Mitsubishi used microwaves to deliver 1.8 kilowatts of power - enough to run an electric kettle - through the air with pinpoint accuracy to a receiver (right) 170ft (55 metres) away
The test, which took place at Kobe Shipyard & Machinery Works in Nagoya, Japan, will help Jaxa devise its long-awaited space solar power system. Mitsubishi used microwaves to deliver 1.8 kilowatts of power - enough to run an electric kettle - through the air with pinpoint accuracy to a receiver (right) 170ft (55 metres) away
The test, which took place at Kobe Shipyard & Machinery Works in Nagoya, Japan, will help Jaxa devise its long-awaited space solar power system. Mitsubishi used microwaves to deliver 1.8 kilowatts of power - enough to run an electric kettle - through the air with pinpoint accuracy to a receiver (right) 170ft (55 metres) away


In a separate project, a Japanese firm last year revealed plans to cover the moon in a huge swathe of solar panels and use them to power homes here on Earth
 In a separate project, a Japanese firm last year revealed plans to cover the moon in a huge swathe of solar panels and use them to power homes here on Earth


But the Japanese research offers the possibility that humans will one day be able to farm an inexhaustible source of energy in space.
The idea, said the Jaxa spokesman, would be for microwave-transmitting solar satellites - which would have sunlight-gathering panels and antennae - to be set up about 22,300 miles (36,000km) from the Earth.

'But it could take decades before we see practical application of the technology - maybe in the 2040s or later,' he said.

'There are a number of challenges to overcome, such as how to send huge structures into space, how to construct them and how to maintain them.'

The idea of space-based solar power generation emerged among US researchers in the 1960s and Japan's SSPS programme, chiefly financed by the industry ministry, started in 2009, he said.

COULD A SOLAR FARM IN SPACE POWER OUR FUTURE?

Space-based solar power – once the stuff of science-fiction – could be available sooner than expected if Japan has its way
Space-based solar power – once the stuff of science-fiction – could be available sooner than expected if Japan has its way


Solar power has had a difficult start on Earth thanks to inefficient panels and high costs. But in space, scientists believe it could transform the way we generate energy.

Now, the space-based solar power – once the stuff of science-fiction – could be available sooner than expected if Japan has its way.

Within 25 years, the country plans to make space-based solar power a reality, according to a proposal from the Japan Aerospace Exploration Agency (Jaxa).

In a recent IEEE article by Susumu Sasaki, a professor emeritus at Jaxa, outlined the agency's plans create a 1.8 mile long (3 km) man-made island in the harbour of Tokyo Bay.

The island would be studded with 5 billion antennas working together to convert microwave energy into electricity.

The microwaves would be beamed down from a number of giant solar collectors in orbit 22,400 miles (36,000 km) above the Earth. 
Resource-poor Japan has to import huge amounts of fossil fuel.
It has become substantially more dependent on these imports as its nuclear power industry shut down in the aftermath of the disaster at Fukushima in 2011.

In a separate project, a Japanese firm last year revealed plans to cover the moon in a huge swathe of solar panels and use them to power homes here on Earth.

Shimizu Corporation's Luna Ring project would stretch almost 6,790 miles (11,000km) around the moon's equator and a field of solar panels would form a belt.

Energy captured by these panels would then be sent to Earth using microwaves and laser lights could be beamed directly to countries where it is needed.

According to the plans, the project would produce around 13,000 terrawatts of continuous solar energy. At present, the world's population consumes about 15 terawatts of power each year.

The company claims the plans would not only provide an 'almost inexhaustible' energy supply, it would stop the rise of global warming caused by carbon dioxide from current energy sources. 

Shimizu Corporation's Luna Ring project would stretch almost 6,790 miles (11,000km) around the moon's equator and a field of solar panels would form a belt
Shimizu Corporation's Luna Ring project would stretch almost 6,790 miles (11,000km) around the moon's equator and a field of solar panels would form a belt

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Confirmed: Jupiter’s moon Ganymede has a salt water ocean

GanymedeExcerpt from latimes.comAstronomers have found the most conclusive evidence yet that a large watery ocean lies beneath the surface of Jupiter's moon Ganymede.Scientists have suspected for decades that a subterranean ocean ...

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Chances of Exoplanet Life ‘Impossible’? Or ‘100 percent’?


Kepler’s Exoplanets: A map of the locations of exoplanets, of various masses, in the Kepler field of view. 1,235 candidates are plotted (NASA/Wendy Stenzel)


 news.discovery.com 

Just in case you haven’t heard, our galaxy appears to be teeming with small worlds, many of which are Earth-sized candidate exoplanets and dozens appear to be orbiting their parent stars in their “habitable zones.”

Before Wednesday’s Kepler announcement, we knew of just over 500 exoplanets orbiting stars in the Milky Way. Now the space telescope has added another 1,235 candidates to the tally — what a difference 24 hours makes.

Although this is very exciting, the key thing to remember is that we are talking about exoplanet candidates, which means Kepler has detected 1,235 exoplanet signals, but more work needs to be done (i.e. more observing time) to refine their orbits, masses and, critically, to find out whether they actually exist.

But, statistically speaking, a pattern is forming. Kepler has opened our eyes to the fact our galaxy is brimming with small worlds — some candidates approaching Mars-sized dimensions!

Earth-Brand™ Life

Before Kepler, plenty of Jupiter-sized worlds could be seen, but with its precision eye for spotting the tiniest of fluctuations of star brightness (as a small exoplanet passes between Kepler and the star), the space telescope has found that smaller exoplanets outnumber the larger gas giants.

Needless to say, all this talk of “Earth-sized” worlds (and the much-hyped “Earth-like” misnomer) has added fuel to the extraterrestrial life question: If there’s a preponderance of small exoplanets — some of which orbit within the “sweet-spot” of the habitable zones of their parent stars — could life as we know it (or Earth-Brand™ Life as I like to call it) also be thriving there?
Before I answer that question, let’s turn back the clock to Sept. 29, 2010, when, in the wake of the discovery of the exoplanet Gliese 581 g, Steven Vogt, professor of astronomy and astrophysics at University of California Santa Cruz, told Discovery News: “Personally, given the ubiquity and propensity of life to flourish wherever it can, I would say that the chances for life on [Gliese 581 g] are 100 percent. I have almost no doubt about it.”

Impossible? Or 100 Percent?

As it turns out, Gliese 581 g may not actually exist — an excellent example of the progress of science scrutinizing a candidate exoplanet in complex data sets as my Discovery News colleague Nicole Gugliucci discusses in “Gliese 581g and the Nature of Science” — but why was Vogt so certain that there was life on Gliese 581 g? Was he “wrong” to air this opinion?

Going to the opposite end of the spectrum, Howard Smith, an astrophysicist at Harvard University, made the headlines earlier this year when he announced, rather pessimistically, that aliens will unlikely exist on the extrasolar planets we are currently detecting.
“We have found that most other planets and solar systems are wildly different from our own. They are very hostile to life as we know it,” Smith told the UK’s Telegraph.

Smith made comparisons between our own solar system with the interesting HD 10180 system, located 127 light-years away. HD 10180 was famous for a short time as being the biggest star system beyond our own, containing five exoplanets (it has since been trumped by Kepler-11, a star system containing six exoplanets as showcased in Wednesday’s Kepler announcement).

One of HD 10180′s worlds is thought to be around 1.4 Earth-masses, making it the smallest detected exoplanet before yesterday. Alas, as Smith notes, that is where the similarities end; the “Earth-sized” world orbiting HD 10180 is too close to its star, meaning it is a roasted exoplanet where any atmosphere is blasted into space by the star’s powerful radiation and stellar winds.
The Harvard scientist even dismissed the future Kepler announcement, pointing out that upcoming reports of habitable exoplanets would be few and far between. “Extrasolar systems are far more diverse than we expected, and that means very few are likely to support life,” he said.

Both Right and Wrong

So what can we learn about the disparity between Vogt and Smith’s opinions about the potential for life on exoplanets, regardless of how “Earth-like” they may seem?

Critically, both points of view concern Earth-Brand™ Life (i.e. us and the life we know and understand). As we have no experience of any other kind of life (although the recent eruption of interest over arsenic-based life is hotly debated), it is only Earth-like life we can realistically discuss.

We could do a Stephen Hawking and say that all kinds of life is possible anywhere in the cosmos, but this is pure speculation. Science only has life on Earth to work with, so (practically speaking) it’s pointless to say a strange kind of alien lifeform could live on an exoplanet where the surface is molten rock and constantly bathed in extreme stellar radiation.

If we take Hawking’s word for it, Vogt was completely justified for being so certain about life existing on Gliese 581 g. What’s more, there’s no way we could prove he’s wrong!

But if you set the very tight limits on where we could find Earth-like life, we are suddenly left with very few exoplanet candidates that fit the bill. Also, just because an Earth-sized planet might be found in the habitable zone of its star, doesn’t mean it’s actually habitable. There are many more factors to consider. So, in this case, Smith’s pessimism is well placed.

Regardless, exoplanet science is in its infancy and the uncertainty with the “is there life?” question is a symptom of being on the “raggedy edge of science,” as Nicole would say. We simply do not know what it takes to make a world habitable for any kind of life (apart from Earth), but it is all too tempting to speculate as to whether a race of extraterrestrials, living on one of Kepler’s worlds, is pondering these same questions.

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Far Flung Star Cluster Found at Milky Way’s Edge

Astronomers in Brazil have discovered a cluster of stars forming at the edge of the Milky Way, according to a press release from the Royal Astronomical Society.




Excerpt from  news.discovery.com


This is unusual because it was believed that stars generally take form closer to the center of our spiral-shaped galaxy, rather than from its swirling, spiral arms, which are thousands of light-years away. These two clusters of stars — named Camargo 438 and 439 — were seen in a cloud at the galaxy’s outskirts.

Denilso Camargo, an astronomer at the Federal University of Rio Grande do Sul in Porto Alegre, Brazil, led a team that analyzed data from NASA’s orbiting Wide-Field Infrared Survey Explorer (WISE) observatory. They zeroed in on dense clumps of gas in so-called giant molecular clouds(GMCs) that are known to generate stars. GMCs are mainly located in the inner part of the galactic disc.

The new star clusters lie about 16,000 light-years away from the main disk of the Milky Way galaxy. How did they form there? The scientists aren’t yet sure but Camargo theorizes that one of two scenarios could have led to the stars’ formation.

In the first scenario, called the “chimney model,” supernovas could have flung the gas and dust that formed the cloud out of the Milky Way. Another explanation is the material could have drifted in from outside the galaxy.


“Our work shows that the space around the Galaxy is a lot less empty that we thought,” said Camargo. “The new clusters of stars are truly exotic.”

Camargo’s team published their results in the journal Monthly

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Exoplanet Imager Begins Hunt for Alien Worlds


This infrared image shows the dust ring around the nearby star HR 4796A in the southern constellation of Centaurus.


Excerpt from news.discovery.com

By Ian O'Neill

A new instrument attached to one of the most powerful telescopes in the world has been switched on and acquired its ‘first light’ images of alien star systems and Saturn’s moon Titan.
The Spectro-Polarimetric High-contrast Exoplanet REsearch (or SPHIRES) instrument has been recently installed at the ESO’s Very Large Telescope’s already impressive suite of sophisticated instrumentation. The VLT is located in the ultra-dry high-altitude climes of the Atacama Desert in Chile.

In the observation above, an ‘Eye of Sauron‘-like dust ring surrounding the star HR 4796A in the southern constellation of Centaurus, a testament to the sheer power of the multiple technique SPHIRES will use to acquire precision views of directly-imaged exoplanets.

The biggest problem with trying to directly image a world orbiting close to its parent star is that of glare; stars are many magnitudes brighter that the reflected light from its orbiting exoplanet, so how the heck are you supposed to gain enough contrast between the bright star and exoplanet to resolve the two? The SPHIRES instrument is using a combination of three sophisticated techniques to remove a star’s glare and zero-in on its exoplanetary targets.

This infrared image of Saturn’s largest moon, Titan, was one of the first produced by the SPHERE instrument soon after it was installed on ESO’s Very Large Telescope in May 2014.
ESO 
The first technique, known as adaptive optics, is employed by the VLT itself. By firing a laser into the Earth’s atmosphere during the observation, a gauge on the turbulence in the upper atmospheric gases can be measured and the effects of which can be removed from the imagery. Any blurriness caused by our thick atmosphere can be adjusted for.

Next up is a precision coronograph inside the instrument that blocks the light from the target star. By doing this, any glare can be removed and any exoplanet in orbit may be bright enough to spot.

But the third technique, which really teases out any exoplanet signal, is the detection of different polarizations of light from the star system. The polarization of infrared light being generated by the star and the infrared glow from the exoplanet are very subtle. SPHIRES can differentiate between the two, thereby further boosting the observation’s contrast.

“SPHERE is a very complex instrument. Thanks to the hard work of the many people who were involved in its design, construction and installation it has already exceeded our expectations. Wonderful!” said Jean-Luc Beuzit, of the Institut de Planétologie et d’Astrophysique de Grenoble, France and Principal Investigator of SPHERE, in an ESO press release.

The speed and sheer power of SPHIRES will be an obvious boon to astronomers zooming in on distant exoplanets, aiding our understanding of these strange new worlds.


The star HR 7581 (Iota Sgr) was observed in SPHERE survey mode (parallel observation in the near infrared with the dual imaging camera and the integral field spectrograph ). A very low mass star, more than 4000 times fainter that its parent star, was discovered orbiting Iota Sgr at a tiny separation of 0.24". This is a vital demonstration of the power of SPHERE to image faint objects very close to bright ones.
ESO

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Bird Thought To Be Extinct Resurfaces In Myanmar

Jerdon's BabblerExcerpt from techtimes.comJerdon's Babbler is a species of bird that was believed to be extinct until this species unexpectedly resurfaced in Myanmar. This brown and white bird is roughly the size of a house sparrow.The bird was last ...

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Hubble’s ‘Einstein Cross’ Marks the Space-Warping Spot


Image: Einstein Cross revealed
Flash from the supernova's blast has been warped into four points of light surrounding an elliptical galaxy in a cluster called MACS J1149.2+2223, which is 5 billion light-years away in the constellation Leo.


Excerpt from nbcnews.com
By Alan Boyle


One hundred years after Albert Einstein published his theory of general relativity, the Hubble Space Telescope has provided a demonstration of the theory at work: a picture of a distant galaxy so massive that its gravitational field is bending the light from an even more distant supernova. 

The image, released Thursday, shows how the flash from the supernova's blast has been warped into four points of light surrounding an elliptical galaxy in a cluster called MACS J1149.2+2223, which is 5 billion light-years away in the constellation Leo. 

"It really threw me for a loop when I spotted the four images surrounding the galaxy," Patrick Kelly, an astronomer from the University of California at Berkeley, said in a news release. "It was a complete surprise." 

Maybe it shouldn't have been. The configuration is known as an Einstein Cross. It's a well-known but rarely seen effect of gravitational lensing, which is in line with Einstein's assertion that a massive object warps the fabric of space-time — and thus warps the path taken by light rays around the object. 

In this case, the light rays are coming from a stellar explosion that's directly behind the galaxy, but 4.3 million light-years more distant. Computer models suggest that the four-pointed cross will eventually fade away, to be followed within the next five years by the reappearance of the supernova's flash as a single image. 

Kelly is part of a research collaboration known as the Grism Lens Amplified Survey from Space, or GLASS. The collaboration is working with the Frontier Field Supernova team, or FrontierSN, to analyze the exploding star. He's also the lead author of a paper on the phenomenon that's being published this week by the journal Science as part of a package marking the 100th anniversary of Einstein's general relativity theory. 

The researchers suggest that a high-resolution analysis of the gravitational lensing effect can lead to better measurements of cosmic distances and galactic masses, including the contribution from dark matter. The Hubble team says the faraway supernova has been named "Refsdal" in honor of Norwegian astronomer Sjur Refsdal, who proposed using time-delayed images from a lensed supernova to study the expansion of the universe. 

"Astronomers have been looking to find one ever since," UCLA astronomer Tommaso Treu, the GLASS project's principal investigator, said in Thursday's news release. "The long wait is over!" 

The Einstein Cross is the subject of a Google+ Hangout at 3 p.m. ET Thursday, presented by the Hubble science team. You can watch the event now or later via YouTube. Check out a preprint version of the Science report.

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This Awesome 3D View Of Deep Space May Be The Best Ever

The background image in this composite shows the Hubble Space Telescope image of the region known as the Hubble Deep Field South. The boxes show distant galaxies that were invisible to Hubble.Excerpt from  huffingtonpost.comAlong with Earthrise ...

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Let There Be Light! Photo Shows Light As Wave And Particle For First Time


Light as a particle and a wave


Excerpt from escapistmagazine.com

According to quantum mechanics light acts as both a particle and a wave, but now we can finally see what that looks like.

Quantum mechanics is an incredibly complex field for a simple reason: So much of what it studies can be two different things at the exact same time. Light is a great example since it behaves like both a particle and a wave, but only appears in one state during experiments. Mathematically speaking, we have to treat light as both ways for the universe to make sense but actually confirming it visually has been impossible. Or at least that was the case until scientists from Switzerland's École polytechnique fédérale de Lausanne developed their own unique photography method.
The image was created by shooting a pulse of laser light at a metallic nanowire to make its charged particles vibrate. Next the scientists fired a stream of electrons past the wire holding the trapped light. When the two collided, it created an energy exchange that could be photographed from the electron microscope.

So what does this mean when looking at the photograph? When the photons and electrons collide, they either slow down or speed up, which creates a visualization of a light wave. At the same time the speed change appears as a quanta - packets of energy - transferred between the electrons and photons as particles. In other words, it's the first case of observing light particles and waves simultaneously.

"This experiment demonstrates that, for the first time ever, we can film quantum mechanics - and its paradoxical nature - directly," research leader Fabrizio Carbone explained. This has enormous implications not only for quantum research, but also quantum-based technologies still in development. "Being able to image and control quantum phenomena at the nanometer scale like this opens up a new route towards quantum computing," he continued.

The experiment results were posted in today's Nature Communications, which will help other scientists build on this research with further studies. After all, it's not like we've unlocked all of light's secrets yet - we can barely even tell what color a dress is sometimes.

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Should Humanity Try to Contact Alien Civilizations?



Some researchers want to use big radio dishes like the 305-meter Arecibo Observatory in Puerto Rico to announce our presence to intelligent aliens.



Excerpt from space.com
by Mike Wall

Is it time to take the search for intelligent aliens to the next level?
For more than half a century, scientists have been scanning the heavens for signals generated by intelligent alien life. They haven't found anything conclusive yet, so some researchers are advocating adding an element called "active SETI" (search for extraterrestrial intelligence) — not just listening, but also beaming out transmissions of our own designed to catch aliens' eyes.

Active SETI "may just be the approach that lets us make contact with life beyond Earth," Douglas Vakoch, director of interstellar message composition at the SETI Institute in Mountain View, California, said earlier this month during a panel discussion at the annual meeting of the American Association for the Advancement of Science (AAAS) in San Jose.

Seeking contact


Vakoch envisions using big radio dishes such as the Arecibo Observatory in Puerto Rico to blast powerful, information-laden transmissions at nearby stars, in a series of relatively cheap, small-scale projects.

"Whenever any of the planetary radar folks are doing their asteroid studies, and they have an extra half an hour before or after, there's always a target star readily available that they can shift to without a lot of extra slough time," he said.

The content of any potential active SETI message is a subject of considerable debate. If it were up to astronomer Seth Shostak, Vakoch's SETI Institute colleague, we'd beam the entire Internet out into space.

"It's like sending a lot of hieroglyphics to the 19th century — they [aliens] can figure it out based on the redundancy," Shostak said during the AAAS discussion. "So, I think in terms of messages, we should send everything."

While active SETI could help make humanity's presence known to extrasolar civilizations, the strategy could also aid the more traditional "passive" search for alien intelligence, Shostak added.
"If you're going to run SETI experiments, where you're trying to listen for a putative alien broadcast, it may be very instructive to have to construct a transmitting project," he said. "Because now, you walk a mile in the Klingons' shoes, assuming they have them."

Cause for concern?

But active SETI is a controversial topic. Humanity has been a truly technological civilization for only a few generations; we're less than 60 years removed from launching our first satellite to Earth orbit, for example. So the chances are that any extraterrestrials who pick up our signals would be far more advanced than we are. 

This likelihood makes some researchers nervous, including famed theoretical physicist Stephen Hawking.

"Such advanced aliens would perhaps become nomads, looking to conquer and colonize whatever planets they could reach," Hawking said in 2010 on an episode of "Into the Universe with Stephen Hawking," a TV show that aired on the Discovery Channel. "If so, it makes sense for them to exploit each new planet for material to build more spaceships so they could move on. Who knows what the limits would be?"

Astrophysicist and science fiction author David Brin voiced similar concerns during the AAAS event, saying there's no reason to assume that intelligent aliens would be altruistic.

"This is an area in which discussion is called for," Brin said. "What are the motivations of species that they might carry with them into their advanced forms, that might color their cultures?"

Brin stressed that active SETI shouldn't be done in a piecemeal, ad hoc fashion by small groups of astronomers.

"This is something that should be discussed worldwide, and it should involve our peers in many other specialties, such as history," he said. "The historians would tell us, 'Well, gee, we have some examples of first-contact scenarios between advanced technological civilizations and not-so-advanced technological civilizations.' Gee, how did all of those turn out? Even when they were handled with goodwill, there was still pain."

Out there already

Vakoch and Shostak agreed that international discussion and cooperation are desirable. But Shostak said that achieving any kind of consensus on the topic of active SETI may be difficult. For example, what if polling reveals that 60 percent of people on Earth are in favor of the strategy, while 40 percent are opposed?

"Do we then have license to go ahead and transmit?" Shostak said. "That's the problem, I think, with this whole 'let's have some international discussion' [idea], because I don't know what the decision metric is."

Vakoch and Shostak also said that active SETI isn't as big a leap as it may seem at first glance: Our civilization has been beaming signals out into the universe unintentionally for a century, since the radio was invented.

"The reality is that any civilization that has the ability to travel between the stars can already pick up our accidental radio and TV leakage," Vakoch said. "A civilization just 200 to 300 years more advanced than we are could pick up our leakage radiation at a distance of several hundred light-years. So there are no increased dangers of an alien invasion through active SETI."

But Brin disputed this assertion, saying the so-called "barn door excuse" is a myth.

"It is very difficult for advanced civilizations to have picked us up at our noisiest in the 1980s, when we had all these military radars and these big television antennas," he said.

Shostak countered that a fear of alien invasion, if taken too far, could hamper humanity's expansion throughout the solar system, an effort that will probably require the use of high-powered transmissions between farflung outposts.

"Do you want to hamstring all that activity — not for the weekend, not just shut down the radars next week, or active SETI this year, but shut down humanity forever?" Shostak said. "That's a price I'm not willing to pay."

So the discussion and debate continues — and may continue for quite some time.

"This is the only really important scientific field without any subject matter," Brin said. "It's an area in which opinion rules, and everybody has a very fierce opinion."

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