Video – A large part of the world lacks access to clean drinking water. Engineer Michael Pritchard did something about it — he created the portable Lifesaver filter, which can make the most revolting water drinkable in seconds. See an amazing demo below. [...]
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| 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.)
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| 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."
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."
Excerpt from techtimes.comScientists are seeking a core sample from the Chicxulub crater that marks the remains of an asteroid impact which ended the age of the dinosaurs nearly 66 million years ago.That geological feature will be probed by scientist...
Excerpt from hubpages.com By Stephanie HicksWhat is Narcissism?Like many other psychological issues, there is a range of narcissism from mild to severe. Because of our inherent ego (as analyzed by Freud), a tendency to want to protect, celeb...
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| WHAT’S FOR DINNER? Signals detected by the Parkes radio telescope (pictured) suggest that intelligent life in the universe has a penchant for leftovers. |
Excerpt from sciencenews.org
Mysterious radio signals detected by the Parkes telescope appear to come from an advanced civilization in the Milky Way.
Unfortunately, it’s the one civilization we already know about.
Microwave ovens opened before they’re done cooking have been muddling the hunt for far more distant radio signals, researchers report online April 9 at arXiv.org. Astronomers have had to contend with enigmatic flares dubbed “perytons” ever since discovering equally puzzling fast radio bursts, or FRBs (SN: 8/9/14, p. 22), in 2007. Perytons and FRBs are quite similar, except that astronomers realized that perytons originate on Earth, possibly from some meteorological phenomenon, while FRBs come from other galaxies.
Three perytons in January coincided with independently detected blasts of 2.4 gigahertz radio waves — the same frequency that microwave ovens use to heat food. So researchers at the Parkes telescope in Australia spent weeks heating mugs of water while moving the massive radio dish around the sky, trying to re-create the phenomenon. Finally, researchers tried opening the oven door mid-cooking instead of letting the timer run out. Suddenly, perytons started showing up in the data.
The source of the galactic FRBs remain an intriguing mystery. Astronomers suspect they have something to do with imploding neutron stars or eruptions on magnetars. At this point, however, they might want to consider extraterrestrials nuking frozen pizzas.
Excerpt from eaglecurrent.com NASA is joining in an effort to have an understanding of the presence of a methane hotspot over the 4 corners area of the United States. How severe is the atmospheric feature?A methane hotspot hovering over t...
Excerpt from huffingtonpost.comNASA's top scientist predicts that we'll find signs of alien life by 2025, with even stronger evidence for extraterrestrials in the years that follow. "I think we're going to have strong indications of life beyond Ea...
Artist impression of the protoplanetary disk surrounding the young star MWC 480. ALMA has detected the complex organic molecule methyl cyanide in the outer reaches of the disk in the region where comets are believed to form. This is another indication that complex organic chemistry, and potentially the conditions necessary for life, is universal. (B. Saxton/NRAO/AUI/NSF)
Excerpt from washingtonpost.com
We're not special. Or our complex organic molecules aren't, anyway. And that's good news in the hunt for extraterrestrial life.
In a new study published Wednesday in Nature, astronomers found the first signs of the complex, carbon-based molecules that make life possible on Earth in a protoplanetary disk; the region where cosmic building blocks gather to create planets in a brand-new star system. The cyanides found there are essential to life as we know it: without them, there would be no proteins.
"We know when our own solar system was very young, it was rich in water and complex organics. We know that from observing comets," explained study author Karin Öberg, an assistant professor of astronomy at Harvard. Comets have kept the molecules of our solar system's early days locked up tight ever since, which is why scientists are so eager to study them for clues about Earth's formation. These comets show us that certain organic molecules were common in our solar system's pre-planetary days.
But this is the first time we've seen evidence of such molecules ready to seed another star system with planets that could support life.
"We're finding that we're not that special," Öberg said. "Other young solar systems in the making are also rich in the same volatiles, and in similar proportions."
And in this case, she said, being not-special is a great thing: If other solar systems formed just the way ours did, we can hope that they formed some kind of life, too.
Öberg and her colleagues found the molecules using the Atacama Large Millimeter/submillimeter Array (ALMA), a radio telescope with some pretty sweet resolution. They spotted the complex organics as much as 15 billion kilometers from the star itself, which they believe is right smack dab in the middle of the system's comet-forming region. That means the organics could get locked away in comets, just as the ones in our solar system were, and go out to seed future planets with them (as some believe was the case with Earth).
"It was kind of a chance discovery, because we weren't targeting this specific molecule," Öberg said. So she and her team need to go back and look more systematically. She also hopes they'll be able to find more systems to look at. The star they've observed -- MWC 480, located some 455 light-years away in the Taurus star-forming region -- is twice the mass of the sun, so they also hope to find some that are more similar to our host star.
"We of course want to know whether this is a really common thing or if we just lucked out on this one," Öberg said.
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| Researchers have identified thousands of glacier-like formations on the planet. NASA/Levy et al./Nanna Karlsson |
Excerpt from news.discovery.com
Glaciers beneath the dusty sands of Mars contain enough water to coat the planet with more than three feet of ice, a new study shows.
“We have calculated that the ice in the glaciers is equivalent to over 150 billion cubic meters of ice — that much ice could cover the entire surface of Mars with 1.1 meters (3.6 feet) of ice,” Nanna Bjørnholt Karlsson, a post-doctoral researcher the Niels Bohr Institute at the University of Copenhagen, said in a statement.
Radar images previously revealed thousands of buried glacier-like formations in the planet’s northern and southern hemispheres.
That data has now been incorporated into computer models of ice flow to determine the glaciers’ size and hence how much water they contain.
“We have looked at radar measurements spanning 10 years back in time to see how thick the ice is and how it behaves. A glacier is, after all, a big chunk of ice and it flows and gets a form that tells us something about how soft it is. We then compared this with how glaciers on Earth behave and from that we have been able to make models for the ice flow,” she said.
The glaciers are located in belts around Mars between 30 degrees and 50 degrees latitude, roughly equivalent to just south of Denmark’s location on Earth. The glaciers are found on both the northern and southern hemispheres.
The finding could be an important clue to what happened to Mars’ water. The planet, which is now a cold, dry desert, once had oceans, lakes and habitats suitable for microbial life, results from past and ongoing science missions show.
“The ice at the mid-latitudes is an important part of Mars’ water reservoir,” Karlsson said.
Scientists suspect the thick layer of dust covering the ice has saved if from evaporating out into space.
The study appears in this week’s Geophysical Research Letters.
Excerpt from foxnews.com
Eleven fast radio bursts from space seem to follow a strange mathematical pattern, according to a new study – and it has researchers scratching their heads.
According to study co–authors Michael Hippke of the Institute of Data Analysis in Neukirchen-Vluyn, Germany, and John Learned of the University of Hawaii in Manoa, the bursts– which were first detected in 2001 – all had dispersion measures that were integer multiples of the same number: 187.5. “The astronomers that found [the bursts] have not seen such things before and do not understand them,” Learned told FoxNews.com.
Nobody knows what causes fast radio bursts, known as FRBs. They only last a few milliseconds, and only one so far has been captured live (by the Parkes Telescope in Australia last year). Though the bursts release just as much energy in a few milliseconds as the sun does in a month, their brevity indicates that the source must be small, with estimates being several hundred miles across at most.
Researchers use dispersion measures, which records how much “space gunk” the burst has passed through, to estimate the distance an FRB has travelled. For instance, a low frequency FRB will have more gunk on it, indicating a longer trip, whereas a high frequency FRB will be cleaner, indicating it came from closer to Earth.
The fact that all of the FRBs’ dispersion measures are integer multiples of 187.5 has, according to Hippke and Learned’s team’s calculations, a 5 in 10,000 chance of being coincidental. The dispersion measures also indicate that their origin is relatively close to Earth, but unlikely from within our own galaxy.
There are numerous theories on where these bursts came from, including speculation that the messages are from extraterrestrial intelligence. To the scientific community, however, this theory doesn’t really hold water, and is seen as more of a last resort only after all other avenues have been exhausted.
“We think these are likely from some very energetic process, like a burst from a high magnetic field neutron star or energy released [when] two neutron stars merge,” Professor Maura McLaughlin of the West Virginia University Center for Astrophysics explained. “The thing that made people think they were possibly from ETs was a recent paper that showed that one fundamental property is quantized in a way that wouldn't be expected if the signals were naturally occurring. However, I imagine that correlation will totally go away once more are discovered.”
Learned himself is dubious of an alien source as well, noting that he and Hippke only noted the dispersion measures’ “peculiar” pattern, and that they may even be coming from Earth. “We are now leaning more towards a terrestrial, anthropogenic interpretation,” he said. “At this point I would place my money on some sort of governmental satellite, not a natural phenomena, but I would not bet much. More data, which reportedly [is] being analyzed but which we have no insider information about yet, will be most interesting and refute or confirm our hypotheses.” He also noted that he’d only look to an ETI interpretation once all other possibilities have been eliminated.
As for McLaughlin, she believes there’s no way the FRBs could be messages from aliens, as the signals are very broadband and emitted over a wide range of radio frequencies. “It would take a LOT of energy for an alien civilization to produce these bursts - they'd need to harness the energy of many, many suns - and there's no real advantage for communication to send a signal over such a large bandwidth.”
Video – Abby Martin takes a look at the 50-year long practice of water fluoridation in America, outlining various health effects and breaking the myth that this practice helps prevent tooth decay [...]
Excerpt from wired.com
In 2007, A Dutch schoolteacher named Hanny var Arkel discovered a weird green glob of gas in space. Sifting through pictures of galaxies online, as part of the citizen science project Galaxy Zoo, she saw a cloud, seemingly glowing, sitting next to a galaxy. Intrigued, astronomers set out to find more of these objects, dubbed Hanny’s Voorwerp (“Hanny’s object” in Dutch). Now, again with the help of citizen scientists, they’ve found 19 more of them, using the Hubble space telescope to snap the eight haunting pictures in the gallery above.
Since var Arkel found the first of these objects, hundreds more volunteers have swarmed to help identify parts of the universe in the Galaxy Zoo gallery. To find this new set, a couple hundred volunteers went through nearly 16,000 pictures online (seven people went through all of them), clicking yes/no/maybe as to whether they saw a weird green blob. Astronomers followed up on the galaxies they identified using ground-based telescopes, and confirmed 19 new galaxies surrounded by green gas.
What causes these wispy tendrils of gas to glow? Lurking at the center of each of these galaxies is a supermassive black hole, millions to billions times as massive as the sun, with gravity so strong that even light can’t escape them. As nearby gas and dust swirls into the black hole, like water circling a drain, that material heats up, producing lots of radiation—including powerful ultraviolet. Beaming out from the galaxy, that ultraviolet radiation strikes nearby clouds of gas, left over from past collisions between galaxies. And it makes the clouds glow an eerie green. “A lot of these bizarre forms we’re seeing in the images arise because these galaxies either interacted with a companion or show evidence they merged with a smaller galaxy,” says William Keel, an astronomer at the University of Alabama, Tuscaloosa.
The eight in this gallery, captured with Hubble, are especially weird. That’s because the quasar, the black-hole engine that’s supposed to be churning out the ultraviolet radiation, is dim—too dim, in fact, to be illuminating the green gas. Apparently, the once-bright quasar has faded. But because that UV light takes hundreds of thousands of years to travel, it can continue to illuminate the gas long after its light source has died away.
That glowing gas can tell astronomers a lot about the quasar that brought it to light. “What I’m so excited about is the fact that we can use them to do archaeology,” says Gabriela Canalizo, an astronomer at the University of California, Riverside, who wasn’t part of the new research. Because the streaks of gas are so vast, stretching up to tens of thousands of light years, the way they glow reveals the history of the radiation coming from the quasar. As the quasar fades, so will the gas’s glow, with the regions of gas closer to the quasar dimming first. By analyzing how the glow dwindles with distance from the quasar, astronomers can determine how fast the quasar is fading. “This was something we’ve never been able to do,” Canalizo says.
Measuring how fast the quasar fades allows astronomers to figure out exactly what’s causing it to turn off in the first place. “What makes them dim is running out of material to eat,” Canalizo says. That could happen if the quasar is generating enough radiation to blow away all the gas and dust surrounding the black hole—the same gas and dust that feeds it. Without a steady diet, the quasar is powerless to produce radiation. Only if more gas happens to make its way toward the black hole can the quasar turn on again. The glowing gas can provide details of this process, and if other mechanisms are at play.
With more powerful telescopes, astronomers will likely find many more. Hanny’s Verwoort, it turns out, may not be that weird after all.
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