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Astronomers Discover Powerful Cosmic Double Whammy



Credit: X-ray: NASA/CXC/SAO/R. van Weeren et al; Optical: NAOJ/Subaru;



Astronomers have discovered a cosmic one-two punch unlike any ever seen before. Two of the most powerful phenomena in the Universe, a supermassive black hole, and the collision of giant galaxy clusters, have combined to create a stupendous cosmic particle accelerator.


By combining data from NASA's Chandra X-ray Observatory, the Giant Metrewave Radio Telescope (GMRT) in India, the NSF's Karl G. Jansky Very Large Array, and other telescopes, researchers have found out what happens when matter ejected by a giant black hole is swept up in the merger of two enormous galaxy clusters.


"We have seen each of these spectacular phenomena separately in many places," said Reinout van Weeren of the Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, Mass., who led the study that appears in the inaugural issue of the journal Nature Astronomy. "This is the first time, however, that we seen them clearly linked together in the same system."


This cosmic double whammy is found in a pair of colliding galaxy clusters called Abell 3411 and Abell 3412 located about two billion light years from Earth. The two clusters are both very massive, each weighing about a quadrillion — or a million billion — times the mass of the Sun.


The comet-shaped appearance of the X-rays detected by Chandra is produced by hot gas from one cluster plowing through the hot gas of the other cluster. Optical data from the Keck Observatory and Japan's Subaru telescope, both on Mauna Kea, Hawaii, detected the galaxies in each cluster.


First, at least one spinning, supermassive black hole in one of the galaxy clusters produced a rotating, tightly-wound magnetic funnel. The powerful electromagnetic fields associated with this structure have accelerated some of the inflowing gas away from the vicinity of the black hole in the form of an energetic, high-speed jet.


Then, these accelerated particles in the jet were accelerated again when they encountered colossal shock waves — cosmic versions of sonic booms generated by supersonic aircraft — produced by the collision of the massive gas clouds associated with the galaxy clusters.


"It's almost like launching a rocket into low-Earth orbit and then getting shot out of the Solar System by a second rocket blast," said co-author Felipe Andrade-Santos, also of the CfA. "These particles are among the most energetic particles observed in the Universe, thanks to the double injection of energy."




This discovery solves a long-standing mystery in galaxy cluster research about the origin of beautiful swirls of radio emission stretching for millions of light years, detected in Abell 3411 and Abell 3412 with the GMRT.


The team determined that as the shock waves travel across the cluster for hundreds of millions of years, the doubly accelerated particles produce giant swirls of radio emission.


"This result shows that a remarkable combination of powerful events generate these particle acceleration factories, which are the largest and most powerful in the Universe," said co-author William Dawson of Lawrence Livermore National Lab in Livermore, Calif. "It is a bit poetic that it took a combination of the world's biggest observatories to understand this."








X-ray: NASA/CXC/SAO/R. van Weeren et al; Optical: NAOJ/Subaru; Radio: NCRA/TIFR/GMRT






X-ray: NASA/CXC/SAO/R. van Weeren et al; Optical: NAOJ/Subaru; Radio: NCRA/TIFR/GMRT






X-ray: NASA/CXC/SAO/R. van Weeren et al; Optical: NAOJ/Subaru; Radio: NCRA/TIFR/GMRT






X-ray: NASA/CXC/SAO/R. van Weeren et al; Optical: NAOJ/Subaru; Radio: NCRA/TIFR/GMRT






X-ray: NASA/CXC/SAO/R. van Weeren et al; Optical: NAOJ/Subaru; Radio: NCRA/TIFR/GMRT

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Researchers have peered through pulsar winds



A composite image of the famous Crab Nebula and Crab Pulsar. The bluish glow in the center of the image is associated with the Crab’s pulsar wind nebula.
NASA, ESA, J. Hester and A. Loll (Arizona State University)



Pulsars serve as cosmic beacons, beaming radiation into space. But not all of these beacons look the same. Now, astronomers have used NASA's Chandra X-ray Observatory to provide a clearer picture of the nebulae that form around pulsars to reconstruct their geometry and explain the differences observed from pulsar to pulsar.


While some pulsars emit radio signals, others emit more energetic gamma rays; some emit both, while some emit only one or the other. With so many variations on a theme possible, astronomers have struggled to create a comprehensive model of pulsars that explains all the available observations. Currently, it’s thought that the differences are a function of geometry — the pulsar’s orientation in space with respect to the Earth can cause us to see or miss certain signals as they sweep out over the cosmos.


In addition to these focused beams of radiation, pulsars also emit a “wind” of charged particles, which form a glowing nebula around the pulsar. These pulsar wind nebulae (PWN) emit radiation of their own, often in X-rays. As the pulsar and its nebula move through the interstellar medium, the PWN can become warped as the interstellar medium pushes against and deforms it.


New Chandra X-ray observations of the Geminga pulsar, one of the closest to the Earth at 800 light-years away, show a PWN with three distinct tails. Two of these tails, which appear to emanate from the pulsar’s poles, stretch out in long arcs away from the star for over half a light-year, like an archer’s bow. The third tail is much smaller, and appears to emanate from the radial region of the pulsar itself.


A Different View


Geminga is a gamma-ray pulsar, emitting beams of highly-energetic radiation. But it is radio quiet, meaning it doesn’t emit detectable radio pulses. By contrast, pulsar B0355+54 is a bright radio pulsar, but isn’t detectable in gamma rays. Not only does B0355+54 emit at different wavelengths, its PWN also looks markedly different from that of the Geminga pulsar. Chandra’s picture of B0355+54 looks more like a jellyfish than a bow — it shows a thick “cap” with long, extended tails that stretch out more than five light-years.


Roger W. Romani, a professor of physics at Stanford University and the principal investigator of the Chandra PWN project, explains in a recent press release that, “By making the 3-D structure of these winds visible, we have shown how one can trace back to the plasma injected by the pulsar at the center.” This information in turn allows astronomers to create more detailed and accurate models of the pulsar and its surroundings, ultimately teasing out the reason for the differences in observed pulses.


Bettina Posselt, a senior research associate in astronomy and astrophysics at Penn State, says that based on these observations, Geminga’s magnetic poles appear to be oriented at the top and bottom of the neutron star from our point of view, which also align with its spin poles. Because these areas are where a pulsar’s radio emission should originate, it makes sense that no radio waves are detected. The pulsar’s gamma rays, however, are created over a larger area at higher altitudes, causing them to sweep out over a larger area of the sky and making them detectable from Earth. The observed tails in the Chandra image may be due to a process called Fermi acceleration, which occurs at the interface between the PWN and the interstellar medium. These results were published in the most recent issue of The Astrophysical Journal.

more at the link...



Press Release   good read...

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NASA's Fermi Discovers the Most Extreme Blazars Yet



NASA's Fermi Gamma-ray Space Telescope has detected the five most distant gamma-ray blazars ever (their locations are seen here in a NASA video still). The light from the blazars dates back to when the universe was between 1.9 and 1.4 billion years old.
Credit: NASA’s Goddard Space Flight Center/Scott Wiessinger



NASA's Fermi Gamma-ray Space Telescope has identified the farthest gamma-ray blazars, a type of galaxy whose intense emissions are powered by supersized black holes. Light from the most distant object began its journey to us when the universe was 1.4 billion years old, or nearly 10 percent of its present age.


"Despite their youth, these far-flung blazars host some of the most massive black holes known," said Roopesh Ojha, an astronomer at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "That they developed so early in cosmic history challenges current ideas of how supermassive black holes form and grow, and we want to find more of these objects to help us better understand the process."


Ojha presented the findings Monday, Jan. 30, at the American Physical Society meeting in Washington, and a paper describing the results has been submitted to The Astrophysical Journal Letters. 


Blazars constitute roughly half of the gamma-ray sources detected by Fermi's Large Area Telescope (LAT). Astronomers think their high-energy emissions are powered by matter heated and torn apart as it falls from a storage, or accretion, disk toward a supermassive black hole with a million or more times the sun's mass. A small part of this infalling material becomes redirected into a pair of particle jets, which blast outward in opposite directions at nearly the speed of light. Blazars appear bright in all forms of light, including gamma rays, the highest-energy light, when one of the jets happens to point almost directly toward us.



Black-hole-powered galaxies called blazars are the most common sources detected by NASA's Fermi. As matter falls toward the supermassive black hole at the galaxy's center, some of it is accelerated outward at nearly the speed of light along jets pointed in opposite directions. When one of the jets happens to be aimed in the direction of Earth, as illustrated here, the galaxy appears especially bright and is classified as a blazar.
Credits: M. Weiss/CfA



Previously, the most distant blazars detected by Fermi emitted their light when the universe was about 2.1 billion years old. Earlier observations showed that the most distant blazars produce most of their light at energies right in between the range detected by the LAT and current X-ray satellites, which made finding them extremely difficult.


Then, in 2015, the Fermi team released a full reprocessing of all LAT data, called Pass 8, that ushered in so many improvements astronomers said it was like having a brand new instrument. The LAT's boosted sensitivity at lower energies increased the chances of discovering more far-off blazars.


The research team was led by Vaidehi Paliya and Marco Ajello at Clemson University in South Carolina and included Dario Gasparrini at the Italian Space Agency's Science Data Center in Rome as well as Ojha. They began by searching for the most distant sources in a catalog of 1.4 million quasars, a galaxy class closely related to blazars. Because only the brightest sources can be detected at great cosmic distances, they then eliminated all but the brightest objects at radio wavelengths from the list. With a final sample of about 1,100 objects, the scientists then examined LAT data for all of them, resulting in the detection of five new gamma-ray blazars.


Expressed in terms of redshift, astronomers' preferred measure of the deep cosmos, the new blazars range from redshift 3.3 to 4.31, which means the light we now detect from them started on its way when the universe was between 1.9 and 1.4 billion years old, respectively.


"Once we found these sources, we collected all the available multiwavelength data on them and derived properties like the black hole mass, the accretion disk luminosity, and the jet power," said Paliya.


Two of the blazars boast black holes of a billion solar masses or more. All of the objects possess extremely luminous accretion disks that emit more than two trillion times the energy output of our sun. This means matter is continuously falling inward, corralled into a disk and heated before making the final plunge to the black hole.


"The main question now is how these huge black holes could have formed in such a young universe," said Gasparrini. "We don't know what mechanisms triggered their rapid development." 


In the meantime, the team plans to continue a deep search for additional examples.


"We think Fermi has detected just the tip of the iceberg, the first examples of a galaxy population that previously has not been detected in gamma rays," said Ajello.


NASA's Fermi Gamma-ray Space Telescope is an astrophysics and particle physics partnership, developed in collaboration with the U.S. Department of Energy and with important contributions from academic institutions and partners in France, Germany, Italy, Japan, Sweden and the United States.



These Powerful Blazars Are the Most Distant Ever Seen

source Space.com


NASAs Fermi Finds the Farthest Blazars

video is 2:30 min.






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NASA licenses advanced COPV tech to Cimarron Composites


Patent: https://www.google.com/patents/US7641949


A composite overwrapped pressure vessel is provided which includes a composite overwrapping material including fibers disposed in a resin matrix. At least first and second kinds of fibers are used. These fibers typically have characteristics of high strength and high toughness to provide impact resistance with increased pressure handling capability and low weight. The fibers are applied to form a pressure vessel using wrapping or winding techniques with winding angles varied for specific performance characteristics. The fibers of different kinds are dispersed in a single layer of winding or wound in distinct separate layers. Layers of fabric comprised of such fibers are interspersed between windings for added strength or impact resistance. The weight percentages of the high toughness and high strength materials are varied to provide specified impact resistance characteristics. The resin matrix is formed with prepregnated fibers or through wet winding. The vessels are formed with or without liners.

Status Report From: Marshall Space Flight Center 

Posted: Tuesday, January 31, 2017
[Federal Register Volume 82, Number 19 (Tuesday, January 31, 2017)] [Notices] [Page 8863] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 2017-02007]
[Notice: (17-003)]
Notice of Intent To Grant Exclusive Patent License
AGENCY: National Aeronautics and Space Administration.
ACTION: Notice of intent to grant exclusive patent license.
SUMMARY: NASA hereby gives notice of its intent to grant an exclusive patent license in the United States to practice the invention described and claimed in U.S. Patent Number 7,867,589 entitled ``Hybrid Cryogenic Tank Construction and Method of Manufacture thereof;''
U.S. Patent Number 7,641,949 entitled ``Pressure Vessel with Improved Impact resistance and Method of making the same;'' U.S. Patent Number 8,561,829 entitled ``Composite Pressure Vessel including Crack Arresting Barrier;'' U.S. Patent Number 8,297,468 entitled ``Fuel Tank for Liquefied Natural Gas'' and U.S. Patent Number 6,953,129 entitled ``Pressure Vessel with Impact and Fire Resistant and Method of making same'' to Cimarron Composites, having its principal place of business in Huntsville, Alabama (USA). The fields of use may be limited to design and manufacturing of composite tanks and pressure vessels for aerospace and other commercial applications.

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"The Calabash Clash"

Article link | ESA Website


Released 03/02/2017 2:27 pm | Copyright ESA/Hubble & NASA | Id 372888


The Calabash Nebula, pictured here — which has the technical name OH 231.8+04.2 — is a spectacular example of the death of a low-mass star like the Sun. This image taken by the NASA/ESA Hubble Space Telescope shows the star going through a rapid transformation from a red giant to a planetary nebula, during which it blows its outer layers of gas and dust out into the surrounding space. The recently ejected material is spat out in opposite directions with immense speed — the gas shown in yellow is moving close to a million kilometres an hour.


Astronomers rarely capture a star in this phase of its evolution because it occurs within the blink of an eye — in astronomical terms. Over the next thousand years the nebula is expected to evolve into a fully fledged planetary nebula.


The nebula is also known as the Rotten Egg Nebula because it contains a lot of sulphur, an element that, when combined with other elements, smells like a rotten egg — but luckily, it resides over 5000 light-years away in the constellation of Puppis (The Poop deck).

Niiiiiice .... :woot:


The reason the ejecta is distended to the (clearly) south pole of the star is due to the direction the star is traveling in space. No longer possessing the gravitational mass to hold on to this material (since the stellar core is now rapidly transitioning to a White Dwarf, if it hasn't already done so), this material is now subject to external forces. We can clearly see the "termination shock", where the influence of this star's energy output (the "solar wind") -- now strongly diminished but still somewhat present -- is colliding with the environment that is outside of its' influence. Because this material is relatively dense, this effect is magnified and we can view it easily. More observation is needed to determine the systems' exact direction of travel, though. I doubt that it is exactly 90 N relative to the star.


That's a very nice image. We can glean a lot from it. :yes: 

Edited by Unobscured Vision
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6 minutes ago, Unobscured Vision said:

Oh, and there are no less than twelve Galaxies in that image. Look closely ... :D 

If you look blurry, its a Soyuz with a large sat fairing.....:woot:

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An exotic binary star system 380 light-years away has been identified as an elusive white dwarf pulsar – the first of its kind ever to be discovered in the universe – thanks to research by the University of Warwick.


Professors Tom Marsh and Boris Gänsicke of the University of Warwick’s Astrophysics Group, with Dr David Buckley from the South African Astronomical Observatory, have identified the star AR Scorpii (AR Sco) as the first white dwarf version of a pulsar - objects found in the 1960s and associated with very different objects called neutron stars.


The white dwarf pulsar has eluded astronomers for over half a century.


AR Sco contains a rapidly spinning, burnt-out stellar remnant called a white dwarf, which lashes its neighbour – a red dwarf - with powerful beams of electrical particles and radiation, causing the entire system to brighten and fade dramatically twice every two minutes. The latest research establishes that the lash of energy from AR Sco is a focused ‘beam’, emitting concentrated radiation in a single direction – much like a particle accelerator – something which is totally unique in the known universe.


AR Sco lies in the constellation Scorpius, 380 light-years from Earth, a close neighbour in astronomical terms. The white dwarf in AR Sco is the size of Earth but 200,000 times more massive, and is in a 3.6 hour orbit with a cool star one third the mass of the Sun. With an electromagnetic field 100 million times more powerful than Earth, and spinning on a period just shy of two minutes, AR Sco produces lighthouse-like beams of radiation and particles, which lash across the face of the cool star, a red dwarf.


As the researchers previously discovered, this powerful light house effect accelerates electrons in the atmosphere of the red dwarf to close to the speed of light, an effect never observed before in similar types of binary stars. The red dwarf is thus powered by the kinetic energy of its spinning neighbour.

The distance between the two stars is around 1.4 million kilometres – which is three times the distance between the Moon and the Earth.

Professor Tom Marsh comments: “The new data show that AR Sco's light is highly polarised, showing that the magnetic field controls the emission of the entire system, and a dead ringer for similar behaviour seen from the more traditional neutron star pulsars.”


Professor Boris Gänsicke comments: "AR Sco is like a gigantic dynamo: a magnet, size of the Earth, with a field that is ~10.000 stronger than any field we can produce in a laboratory, and it is rotating every two minutes. This generates an enormous electric current in the companion star, which then produces the variations in the light we detect." The latest research, ‘Polarimetric evidence of a white dwarf pulsar in the binary system AR Scorpii’, is published in Nature Astronomy.


:) Source


And here is the full Nature.com article on this find - it is long and way way complicated for me to go through the whole thing. Even as someone who studied some of this stuff in College, its beyond me at this point.

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Niiiiice! If the WD is doing this, then it could mean that it was right on the edge of being able to become a Pulsar but lacked the mass to actually do so. Now it's a strange "hybrid" of both a WD and a neutron star. 


Interesting discovery. We need to be observing this one too. There will be loads of great science to be gleaned from it. :yes: 

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I think that article is amazing. The fact that there is a White Dwarf Pulsar, is so great to me for some reason. Like, something they never expected (but I guess was guesstimated about a few years back already) but still found out there. The Universe never ceases to amaze me. And to think, when I studied astrophysics in College back in 95 or so (94 actually, but whatever lol) the amount of stuff we've learned in just 20 years or so, blows my little brain away. Like, literally.


Think about it. They've found WDPs now, gravitational waves, dark energy and dark matter are still unknowns, the fact that there may be as much as 1 trillion galaxies in the observable universe etc etc etc. And all this in just say, 10 years maybe? Imagine what they will find when that big fancy new Hubble replacement launches next year. :p


Not to mention stuff right in our own solar system such as the water discovery on Mars, Pluto's amazing geology etc. But you know, science is poppy ######! Lies I say, lies! :D:D

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Good grief, imagine what they'll be finding with JWST. :yes::D It'll change the game.


Oh, and the proposed upgrades to ESO. (citation here). Then ALMA, Keck, Keck II and Subaru will start looking at proposals for upgrades around 2019 or so.


Can't wait.

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Astronomers Find Faintest Early Galaxies Yet, Probe How the Early Universe Lit Up



8 February 2017
AUSTIN — Astronomers at The University of Texas at Austin have developed a new technique to discover the faintest galaxies yet seen in the early universe —10 times fainter than any previously seen. These galaxies will help astronomers probe a little-understood, but important period in cosmic history. Their new technique helps probe the time a billion years after the Big Bang, when the early, dark universe was flooded with light from the first galaxies.

Rachael Livermore and Steven Finkelstein of the UT Austin Astronomy Department, along with Jennifer Lotz of the Space Telescope Science Institute, went looking for these faint galaxies in images from Hubble Space Telescope’s Frontier Fields survey.
“These galaxies are actually extremely common,” Livermore said. “It’s very satisfying being able to find them.”
These faint, early galaxies gave rise to the Epoch of Reionization, when the energetic radiation they gave off bombarded the gas between all galaxies in the universe. This caused the atoms in this diffuse gas to lose their electrons (that is, become ionized).
Finkelstein explained why finding these faint galaxies is so important. “We knew ahead of time that for our idea of galaxy-powered reionization to work, there had to be galaxies a hundred times fainter than we could see with Hubble,” he said, “and they had to be really, really common.” This was why the Hubble Frontier Fields program was created, he said.



Livermore elaborates: “The problem is, you’re trying to find these really faint things, but you’re looking behind these really bright things. The brightest galaxies in the universe are in clusters, and those cluster galaxies are blocking the background galaxies we’re trying to observe. So what I did was come up with a method of removing the cluster galaxies” from the images.
Her method uses modeling to identify and separate light from the foreground galaxies (the cluster galaxies) from the light coming from the background galaxies (the more-distant, lensed galaxies).
According to Lotz, “This work is unique in its approach to removing this light. This has allowed us to detect more and fainter galaxies than seen in previous studies, and to achieve the primary goal for the Frontier Fields survey.”
Livermore and Finkelstein have used the new method on two of the galaxy clusters in the Frontier Fields project: Abell 2744 and MACS 0416. It enabled them to identify faint galaxies seen when the universe was about a billion years old, less than 10 percent of its current age — galaxies 100 times fainter than those found in the Hubble Ultra Deep Field, for instance, which is the deepest image of the night sky yet obtained.
Their observations showed that these faint galaxies are extremely numerous, consistent with the idea that large numbers of extremely faint galaxies were the main power source behind reionization.

more at the link...




Galaxy Cluster MACS 0416


A Hubble Space Telescope view of the galaxy cluster MACS 0416 is annotated in cyan and magenta to show how it acts as a ‘gravitational lens,’ magnifying more distant background galaxies. Cyan highlights the distribution of mass in the cluster, mostly in the form of dark matter. Magenta highlights the degree to which the background galaxies are magnified, which is related to the mass distribution.
Credit: STScI/NASA/CATS Team/R. Livermore (UT Austin)



Galaxy Cluster Abell 2744


A Hubble Space Telescope view of the galaxy cluster Abell 2744 is annotated in cyan and magenta to show how it acts as a ‘gravitational lens,’ magnifying more distant background galaxies. Cyan highlights the distribution of mass in the cluster, mostly in the form of dark matter. Magenta highlights the degree to which the background galaxies are magnified, which is related to the mass distribution.
Credit: STScI/NASA/CATS Team/R. Livermore (UT Austin)



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"Batch of Earth-sized" planets discovered around TRAPPIST-1.


NASA's Spitzer Space Telescope has revealed the first known system of seven Earth-size planets around a single star. Three of these planets are firmly located in the habitable zone, the area around the parent star where a rocky planet is most likely to have liquid water.



The discovery sets a new record for greatest number of habitable-zone planets found around a single star outside our solar system. All of these seven planets could have liquid water – key to life as we know it – under the right atmospheric conditions, but the chances are highest with the three in the habitable zone.


“This discovery could be a significant piece in the puzzle of finding habitable environments, places that are conducive to life,” said Thomas Zurbuchen, associate administrator of the agency’s Science Mission Directorate in Washington. “Answering the question ‘are we alone’ is a top science priority and finding so many planets like these for the first time in the habitable zone is a remarkable step forward toward that goal.”


At about 40 light-years (235 trillion miles) from Earth, the system of planets is relatively close to us, in the constellation Aquarius. Because they are located outside of our solar system, these planets are scientifically known as exoplanets.


This exoplanet system is called TRAPPIST-1, named for The Transiting Planets and Planetesimals Small Telescope (TRAPPIST) in Chile. In May 2016, researchers using TRAPPIST announced they had discovered three planets in the system. Assisted by several ground-based telescopes, including the European Southern Observatory's Very Large Telescope, Spitzer confirmed the existence of two of these planets and discovered five additional ones, increasing the number of known planets in the system to seven.


The new results were published Wednesday in the journal Nature, and announced at a news briefing at NASA Headquarters in Washington.


Using Spitzer data, the team precisely measured the sizes of the seven planets and developed first estimates of the masses of six of them, allowing their density to be estimated.


Based on their densities, all of the TRAPPIST-1 planets are likely to be rocky. Further observations will not only help determine whether they are rich in water, but also possibly reveal whether any could have liquid water on their surfaces. The mass of the seventh and farthest exoplanet has not yet been estimated – scientists believe it could be an icy, "snowball-like" world, but further observations are needed.


"The seven wonders of TRAPPIST-1 are the first Earth-size planets that have been found orbiting this kind of star," said Michael Gillon, lead author of the paper and the principal investigator of the TRAPPIST exoplanet survey at the University of Liege, Belgium. "It is also the best target yet for studying the atmospheres of potentially habitable, Earth-size worlds."



Full article at NASA




Press release video.



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Vast luminous nebula poses a cosmic mystery



MAMMOTH-1 is an extended blob of gas in the intergalactic medium called an enormous Lyman-alpha nebula (ELAN). The color map and contours denote the surface brightness of the nebula, and the red arrows show its estimated spatial extent.
Cai et al., Astrophysical Journal 



Astronomers have found an enormous, glowing blob of gas in the distant universe, with no obvious source of power for the light it is emitting. Called an "enormous Lyman-alpha nebula" (ELAN), it is the brightest and among the largest of these rare objects, only a handful of which have been observed.


ELANs are huge blobs of gas surrounding and extending between galaxies in the intergalactic medium. They are thought to be parts of the network of filaments connecting galaxies in a vast cosmic web. Previously discovered ELANs are likely illuminated by the intense radiation from quasars, but it's not clear what is causing the hydrogen gas in the newly discovered nebula to emit Lyman-alpha radiation (a characteristic wavelength of light absorbed and emitted by hydrogen atoms).


The newly discovered nebula was found at a distance of 10 billion light years in the middle of a region with an extraordinary concentration of galaxies. Researchers found this massive overdensity of early galaxies, called a "protocluster," through a novel survey project led by Zheng Cai, a Hubble Postdoctoral Fellow at UC Santa Cruz.


"Our survey was not trying to find nebulae. We're looking for the most overdense environments in the early universe, the big cities where there are lots of galaxies," said Cai. "We found this enormous nebula in the middle of the protocluster, near the peak density."



"It's extremely bright, and it's probably larger than the Slug Nebula, but there's nothing else visible except the faint smudge of a galaxy. So it's a terrifically energetic phenomenon without an obvious power source," Prochaska said.


Equally impressive is the enormous protocluster in which it resides, he said. Protoclusters are the precursors to galaxy clusters, which consist of hundreds to thousands of galaxies bound together by gravity. Because protoclusters are spread out over a much larger area of the sky, they are much harder to find than galaxy clusters.


The protocluster hosting the MAMMOTH-1 nebula is massive, with an unusually high concentration of galaxies in an area about 50 million light years across. Because it is so far away (10 billion light years), astronomers are in effect looking back in time to see the protocluster as it was 10 billion years ago, or about 3 billion years after the big bang, during the peak epoch of galaxy formation. After evolving for 10 billion more years, this protocluster would today be a mature galaxy cluster perhaps only one million light years across, having collapsed down to a much smaller area, Prochaska said.

The standard cosmological model of structure formation in the universe predicts that galaxies are embedded in a cosmic web of matter, most of which is invisible dark matter. The gas that collapses to form galaxies and stars traces the distribution of dark matter and extends beyond the galaxies along the filaments of the cosmic web. The MAMMOTH-1 nebula appears to have a filamentary structure that aligns with the galaxy distribution in the large-scale structure of the protocluster, supporting the idea that ELANs are illuminated segments of the cosmic web, Cai said.

"From the distribution of galaxies we can infer where the filaments of the cosmic web are, and the nebula is perfectly aligned with that structure," he said.


Cai and his coauthors considered several possible mechanisms that could be powering the Lyman-alpha emission from the nebula. The most likely explanations involve radiation or outflows from an active galactic nucleus (AGN) that is strongly obscured by dust so that only a faint source can be seen associated with the nebula. An AGN is powered by a supermassive black hole actively feeding on gas in the center of a galaxy, and it is usually an extremely bright source of light (quasars being the most luminous AGNs in visible light).


The intense radiation from an AGN can ionize the gas around it (called photoionization), and this may be one mechanism at work in MAMMOTH-1. When ionized hydrogen in the nebula recombines it would emit Lyman-alpha radiation. Another possible mechanism powering the Lyman-alpha emissions is shock heating by a powerful outflow of gas from the AGN.


The researchers described several lines of evidence supporting the existence of a hidden AGN energizing the nebula, including the dynamics of the gas and emissions from other elements besides hydrogen, notably helium and carbon.


"It has all the hallmarks of an AGN, but we don't see anything in our optical images. I expect there's a quasar that is so obscured by dust that most of its light is hidden," Prochaska said.



Discovery of an Enormous Lyα nebula in a massive galaxy overdensity at z=2.3



Looking back in history...way back....:D

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Ooooo ... we can already do it at small scales within an area. Takes a fair amount of electrical power but it can be done; but fields like that aren't really useful at those small scales for the purposes that they'd be needed for. Something like this, however, is useful but will take an insane amount of power to generate and maintain.


Worth keeping an eye on.

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Just words of caution.....this is model, and a model can be made to simulate anything, particularly when many variables are not well understood.


This is way beyond any capabilities present or far future.


I'll give him big style points for audacity, something to work toward, for the next half century.


This  really belongs in a "science of the far future" category....neat though.



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Well this was from the "by 2050" stuff of the event. Whether you consider that far future or near future - you know :D I certainly think at our current pace of technological improvement we can do this by around 2050 or so. Whether it'll work, is another story.

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2 minutes ago, LOC said:

Well this was from the "by 2050" stuff of the event. Whether you consider that far future or near future - you know :D I certainly think at our current pace of technological improvement we can do this by around 2050 or so. Whether it'll work, is another story.

Just an opinion, but I think it will be way past 2050.....we've been stuck in LEO for 45 years...not a confidence building regime.    :)

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