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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Excerpt from sci-tech-today.com Examining rocks on Mercury's surface, scientists using data from NASA's Messenger spacecraft have revealed that the planet probably had a much stronger magnetic field nearly 4 billion years ago. The fi...
In this image, the magenta color indicates the mysterious glow detected by NASA's NuSTAR space telescope.Excerpt from huffingtonpost.com A mysterious glow has been observed at the center of the Milky Way, and scientists are struggling to figure o...
Excerpt from huffingtonpost.com Sometimes, it's the most fantastical, fictional characters that do the best job of teaching us about reality.New York Times bestselling author T.A. Barron spent decades creating the magical image of Merlin the wiza...
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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."
A Type Ia supernova, SN1994D, is shown exploding in lower left corner of the image at the top of the page of the galaxy NGC 4526 taken by the Hubble Space Telescope. (High-Z Supernova Search Team, HST, NASA)Excerpt from dailygalaxy.com Cer...
Excerpt from thewestsidestory.net
The Universe is expanding and any student of astronomy will vouch to this fact. However according to a team of astronomers the acceleration of the universe may not be as quick as it was assumed earlier.
A team of astronomers have discovered that certain types of supernova are more varied than earlier thought of and in the process have led to the biggest mystery of the universe-how fast is the universe expanding after the big bang?
Peter A. Milne of the University of Arizona said, “We found that the differences are not random, but lead to separating Ia supernovae into two groups, where the group that is in the minority near us are in the majority at large distances — and thus when the universe was younger, there are different populations out there, and they have not been recognized. The big assumption has been that as you go from near to far, type Ia supernovae are the same. That doesn’t appear to be the case.”
Milne said, “The idea behind this reasoning, is that type Ia supernovae happen to be the same brightness — they all end up pretty similar when they explode. Once people knew why, they started using them as mileposts for the far side of the universe.The faraway supernovae should be like the ones nearby because they look like them, but because they’re fainter than expected, it led people to conclude they’re farther away than expected, and this in turn has led to the conclusion that the universe is expanding faster than it did in the past.”
Milne said, “We’re proposing that our data suggest there might be less dark energy than textbook knowledge, but we can’t put a number on it, until our paper, the two populations of supernovae were treated as the same population. To get that final answer, you need to do all that work again, separately for the red and for the blue population.
Type la supernovae are considered as a benchmark for far away sources of light they do have a fraction of variability which has limited our knowledge of the size of the universe.
The distance of objects with the aid of our binocular vision and the best space-based telescopes and most sophisticated techniques works out in the range of ten or twenty thousand light years.
However as compared to the vastness of space, this is just pea nuts.
For Distances greater than that it is imperative to compare the absolute and observed brightness of well understood objects and to use the difference to determine the object’s distance.
In astronomy it is difficult to find an object of known brightness since there are examples of both bright and dim stars and galaxies. However there is one event which can be used to work out its absolute brightness. Supernovas are the final stages of a dying star and it explodes with such violence, the flash can be seen across the vast universe.
Type la Supernovae occurs in a binary star system when a white dwarf scoops off mass from its fellow star. This reproducible mechanism gives a well determined brightness and therefore scientists term such Type la supernovae as ‘standard candles’.
Astronomers found that the Type la supernovae is so uniform that it has been designated as cosmic beacons and used to assess the depths of the universe. It is now revealed that they fall into different populations and are not very uniform as previously thought. .
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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.
Video – This is the incredible story of 32 year old Aaron and his 100 day juice fast. This 10-minute video shows his progress from 333 pounds down to 222 pounds 3 months later. In the last minute you will see his before and after pictures – the difference in his weight and color are astonishing! [...]
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.”
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.
Please fast forward to 13:45 of video presentation:
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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