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Amateurs and professional astronomers alike are thrilled by extreme storms on Uranus

Amateurs and professional astronomers alike are thrilled by extreme storms on Uranus | Amazing Science | Scoop.it

A team led by Berkeley astronomer Imke de Pater has been observing Uranus regularly for years, and recently found that the normally bland face of the planet has become increasingly stormy, with enormous cloud systems so bright that for the first time ever, amateur astronomers are able to see details in the planet's hazy blue-green atmosphere.


“This type of activity would have been expected in 2007, when Uranus’s once-every-42-year equinox occurred and the sun shined directly on the equator,” noted co-investigator Heidi Hammel of the Association of Universities for Research in Astronomy. “But we predicted that such activity would have died down by now. Why we see these incredible storms now is beyond anybody’s guess.”


In total, de Pater, Hammel and their team detected eight large storms on Uranus’s northern hemisphere when observing the planet with the Keck Observatory on Aug. 5 and 6. One was the brightest storm ever seen on Uranus at 2.2 microns, a wavelength that senses clouds just below the tropopause, the lower boundary of the stratosphere – where the pressure ranges from about 300 to 500 mbar, or half the pressure at Earth’s surface. The storm accounted for 30 percent of all light reflected by the rest of the planet at this wavelength. When amateur astronomers heard about the activity, they turned their telescopes on the planet and were amazed to see a bright blotch on the surface of a normally boring blue dot.


French amateur astronomer Marc Delcroix processed the amateur images and confirmed the discovery of a bright spot on an image by French amateur Régis De-Bénedictis, then in others taken by fellow amateurs in September and October. He had his own chance on Oct. 3 and 4 to photograph it with the Pic du Midi one-meter telescope, where on the second night, “I caught the feature when it was transiting, and I thought, ‘Yes, I got it!’” said Delcroix. I was thrilled to see such activity on Uranus. Getting details on Mars, Jupiter or Saturn is now routine, but seeing detail on Uranus and Neptune is the new frontier for us amateurs and I did not want to miss that,” said Delcroix, who works for an auto-parts supplier in Toulouse and has been observing the skies – Jupiter in particular – with his backyard telescope since 2006 and, since 2012, occasionally with the Pic du Midi telescope. “I was so happy to confirm myself these first amateur images on this bright storm on Uranus, feeling I was living a very special moment for planetary amateur astronomy.”

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First comet landing!

First comet landing! | Amazing Science | Scoop.it
20 years planning • 10 years travelling • 4 Billion miles journey
successful landing on a tiny 2.5 mile comet • 320 million miles away from Earth

On 12 November, 2014, Rosetta’s Philae probe is set to make the first-ever landing on a comet when it touches down on Comet 67P/Churyumov–Gerasimenko. Separation of the lander is planned for about 09:03 GMT (10:03 CET), and touch down should follow about seven hours later, at 16:02 GMT (17:02 CET).


Follow this historic event via live updates posted in the following channels:



Webcast will begin 19:00 GMT (20:00 CET) 11 November and continue (with pauses) to cover crucial mission milestones overnight on Tuesday and through Wednesday. Check the ESA TV schedule herefor detailed times.


Updated with news and information direct from the mission operations and science teams.



All channels and webpages, including the Twitter, Rosetta Facebook and ESA Flickr social media accounts, are linked from the main Rosetta mission page: http://rosetta.esa.int


The ROLIS instrument that will take pictures, is a down-looking imager that acquires images during the descent and doubles as a multispectral close-up camera after the landing. The aim of the ROLIS experiment is to study the texture and microstructure of the comet's surface. ROLIS (ROsetta Lander Imaging System) is a descent and close-up camera on the Philae Lander. It has been developed by the DLR Institute of Planetary Research, Berlin. The lander separated from the orbiter at 09:03 GMT (10:03 CET) and touched down on Comet 67P/Churyumov–Gerasimenko seven hours later.

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Beyond Interstellar: New visualizations of the event horizon of black holes

Beyond Interstellar: New visualizations of the event horizon of black holes | Amazing Science | Scoop.it

University of Arizona (UA) astrophysicists are taking the special effects in the movie Interstellar a step further, generating what happens when matter flowing into a black hole crosses the event horizon, the point of no return, and then disappears.


To do that, the astrophysicists are using UA’s new supercomputer — nicknamed El Gato — combining knowledge from mathematical equations and astronomical observations to generate visualizations of an object known by astronomers as Sagittarius A* (“Sagittarius A star”), a supermassive black hole comprising the mass of 4.3 million suns. It is located 26,000 light-years from Earth at the center of our galaxy.


The team just published visualizations of what a space traveler might see upon approaching SgrA* in two reports in theAstrophysical Journal — one focusing on imaging and the other on computing — providing some of the groundwork for the Event Horizon Telescope, or EHT, a huge undertaking involving scientists and observatories around the world to take the first-ever picture of SgrA*.


For the film Interstellar, a special-effects team of about 30 experts reportedly spent up up to 100 hours running calculations to create each frame. “Our team of four here at the UA can produce visuals of a black hole that are more scientifically accurate in a few seconds,” said Feryal Ozel, a UA associate professor of astronomy and physics.


“It’s a bit like gaming on steroids,” she explained. “El Gato uses a massively parallel architecture of hundreds of graphic processors working side by side, with each node functioning as a renderer in real time,” based on algorithms capable of calculating the paths of millions of individual photons in mere seconds as they shoot toward the black hole.

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Exoplanet Survey Satellite TESS mission cleared for next development phase

Exoplanet Survey Satellite TESS mission cleared for next development phase | Amazing Science | Scoop.it

NASA has officially confirmed the Transiting Exoplanet Survey Satellite (TESS) mission, clearing it to move forward into the development phase. This marks a significant step for the TESS mission, which would search the entire sky for planets outside our solar system, known as exoplanets.


TESS is designed to complement several other critical missions in the search for life on other planets. Once TESS finds nearby exoplanets to study and determines their sizes, ground-based observatories and other NASA missions, like the James Webb Space Telescope, would make follow-up observations on the most promising candidates to determine their density and other key properties. By figuring out a planet's characteristics, like its atmospheric conditions, scientists could determine whether the targeted planet has a habitable environment.


"TESS should discover thousands of new exoplanets within two hundred light years of Earth," Ricker said. "Most of these will be orbiting bright stars, making them ideal targets for characterization observations with NASA's James Webb Space Telescope."

"The Webb telescope and other teams will focus on understanding the atmospheres and surfaces of these distant worlds, and someday, hopefully identify the first signs of life outside of our solar system," Volosin said.


TESS will use four cameras to study sections of the sky's north and south hemispheres, looking for exoplanets. The cameras would cover about 90 percent of the sky by the end of the mission. This makes TESS an ideal follow-up to the Kepler mission, which searches for exoplanets in a fixed area of the sky. Because the TESS mission surveys the entire sky, TESS is expected to find exoplanets much closer to Earth, making them easier for further study.


In addition, Ricker said TESS would provide precision, full-frame images for more than 20 million bright stars and galaxies. "This unique new data will comprise a treasure trove for astronomers throughout the world for many decades to come," Ricker said.

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Birth of Planets Revealed in Astonishing Detail in ALMA’s ‘Best Image Ever’

Birth of Planets Revealed in Astonishing Detail in ALMA’s ‘Best Image Ever’ | Amazing Science | Scoop.it

Astronomers have captured the best image ever of planet formation around an infant star as part of the testing and verification process for the Atacama Large Millimeter/submillimeter Array’s (ALMA) new high-resolution capabilities. 

This revolutionary new image reveals in astonishing detail the planet-forming disk surrounding HL Tau, a Sun-like star located approximately 450 light-years from Earth in the constellation Taurus.  

ALMA uncovered never-before-seen features in this system, including multiple concentric rings separated by clearly defined gaps. These structures suggest that planet formation is already well underway around this remarkably young star.

"These features are almost certainly the result of young planet-like bodies that are being formed in the disk. This is surprising since HL Tau is no more than a million years old and such young stars are not expected to have large planetary bodies capable of producing the structures we see in this image," said ALMA Deputy Director Stuartt Corder. 

All stars are believed to form within clouds of gas and dust that collapse under gravity. Over time, the surrounding dust particles stick together, growing into sand, pebbles, and larger-size rocks, which eventually settle into a thin protoplanetary disk where asteroids, comets, and planets form. 

Once these planetary bodies acquire enough mass, they dramatically reshape the structure of their natal disk, fashioning rings and gaps as the planets sweep their orbits clear of debris and shepherd dust and gas into tighter and more confined zones.

The new ALMA image reveals these striking features in exquisite detail, providing the clearest picture to date of planet formation. Images with this level of detail were previously only seen in computer models and artist concepts. ALMA, living up to its promise, has now provided direct proof that nature and theory are very much in agreement. 

"This new and unexpected result provides an incredible view of the process of planet formation. Such clarity is essential to understand how our own Solar System came to be and how planets form throughout the Universe," said Tony Beasley, director of the National Radio Astronomy Observatory (NRAO) in Charlottesville, Virginia, which manages ALMA operations for astronomers in North America. 

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Lucky star escapes black hole with minor damage

Lucky star escapes black hole with minor damage | Amazing Science | Scoop.it
Astronomers have gotten the closest look yet at what happens when a black hole takes a bite out of a star—and the star lives to tell the tale.


We may think of black holes as swallowing entire stars—or any other object that wanders too close to their immense gravity. But sometimes, a star that is almost captured by a black hole escapes with only a portion of its mass torn off. Such was the case for a star some 650 million light years away toward Ursa Major, the constellation that contains the "Big Dipper," where a supermassive black hole tore off a chunk of material from a star that got away.


Astronomers at The Ohio State University couldn't see the star itself with their All-Sky Automated Survey for Supernovae (ASAS-SN, pronounced "assassin"). But they did see the light that flared as the black hole "ate" the material that it managed to capture.


In a paper to appear in the Monthly Notices of the Royal Astronomical Society, they report that the star and the black hole are located in a galaxy outside of the newly dubbed Laniakea Supercluster, of which our home Milky Way Galaxy is a part.


If Laniakea is our galactic "city," this event—called a "tidal disruption event," or TDE— happened in our larger metropolitan area. Still, it's the closest TDE ever spotted, and it gives astronomers the best chance yet of learning more about how supermassive black holes form and grow.


ASAS-SN has so far spotted more than 60 bright and nearby supernovae; one of the program's other goals is to try to determine how often TDEs happen in the nearby universe. But study co-author Krzysztof Stanek, professor of astronomy at Ohio State, and his collaborators were surprised to find one in January 2014, just a few months after ASAS-SN's four telescopes in Hawaii began gathering data.

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Unusual Distribution of Organics Found in Titan’s Atmosphere

Unusual Distribution of Organics Found in Titan’s Atmosphere | Amazing Science | Scoop.it

A new mystery of Titan has been uncovered by astronomers using their latest asset in the high altitude desert of Chile. Using the now fully deployed Atacama Large Millimeter Array (ALMA) telescope in Chile, astronomers moved from observing comets to Titan. A single 3 minute observation revealed organic molecules that are askew in the atmosphere of Titan. The molecules in question should be smoothly distributed across the atmosphere but they are not.


The Cassini/Huygens spacecraft at the Saturn system has been revealing the oddities of Titan to us, with its lakes and rain clouds of methane and an atmosphere thicker than Earth’s. But the new observations by ALMA of Titan underscore how much more can be learned about Titan and also how incredible the ALMA array is.


The ALMA astronomers called it a “brief 3 minute snapshot of Titan.” They found zones of organic molecules offset from the Titan polar regions. The molecules observed were hydrogen isocyanide (HNC) and cyanoacetylene (HC3N). It is a complete surprise to the astrochemist Martin Cordiner, from NASA Goddard Space Flight Center in Greenbelt, Maryland. Cordiner is the lead author of the work published in the latest release of Astrophysical Journal Letters.


The NASA Goddard press release states, “At the highest altitudes, the gas pockets appeared to be shifted away from the poles. These off-pole locations are unexpected because the fast-moving winds in Titan’s middle atmosphere move in an east–west direction, forming zones similar to Jupiter’s bands, though much less pronounced. Within each zone, the atmospheric gases should, for the most part, be thoroughly mixed.”


When one hears there is a strange, skewed combination of organic compounds somewhere, the first thing to come to mind is life. However, the astrochemists in this study are not concluding that they found a signature of life. There are, in fact, other explanations that involve simpler forces of nature. The Sun and Saturn’s magnetic field delivers light and energized particles to Titan’s atmosphere. This energy causes the formation of complex organics in the Titan atmosphere. But how these two molecules – HNC and HC3N came to have a skewed distribution is, as the astrochemists said, “very intriguing.” Cordiner stated, “This is an unexpected and potentially groundbreaking discovery… a fascinating new problem.”

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Far-Out Concepts NASA Selects For Funding

Far-Out Concepts NASA Selects For Funding | Amazing Science | Scoop.it

Sometimes a good idea takes some tinkering. You have a thought that it will work, but what it really requires is you take some money and time and test it out in a small form. This principle is sound if you’re trying to do home renovation (a paint splash on a wall can let you see if the color will work) and it is especially true if you’re planning a multi-million dollar mission to another planet.


This is the thought behind the NASA Innovative Advanced Concepts office, which announced a dozen far-flung drawing-board proposals that received $100,000 in Phase 1 funding for the next 9-12 months. There are vehicles to explore the soupy moon of Titan, a design to snag a tumbling asteroid, and other ideas to explore the solar system. But be patient: These testbed ideas would take decades to come to fruition, if they are even accepted for further study and funding.


Titan Aerial Daughtercraft: A small rotorcraft that can touch down from a balloon or lander.


Titan SubmarineA small submarine would dive into Kraken Mare on Saturn’s moon, and there would be plenty to explore: 984 feet (300 meters) of depth, stretching across 621 miles (1,000 km). 


Comet Hitchhiker: This would be a “tethered” spacecraft that swings from comet to comet to explore icy bodies in the solar system.


Weightless Rendezvous And Net Grapple to Limit Excess Rotation: This idea would capture space debris and small asteroids.


The Aragoscope: A telescope that would look through an opaque disk at a distant object, which is different from the usual mirror arrangement.


Mars Ecopoiesis Test Bed: A machine that would test how well bacteria from Earth could survive on Mars, which could be a precursor to “terraforming” the planet to make it more like our own.


ChipSats: Instead of having an orbiter and a lander in separate missions, why not put them in one?


Swarm Flyby Gravimetry: While whizzing by a comet or asteroid, a single spacecraft would release a swarm of tiny probes.


Probing icy worlds concept: How thick is the ice on Jupiter’s Europa or Ganymede, or Saturn’s Enceladus?


Heliopause Electrostatic Rapid Transit System (HERTS): This would be a mission that goes deep into the solar-system and out to the heliopause, the spot where the sun’s sphere of influence gives way to the interstellar medium.


3D Photocatalytic Air Processor: A new design to make it easier to generate oxygen on a spacecraft, using “abundant high-energy light in space,” the proposal states.


PERIapsis Subsurface Cave OPtical Explorer (PERISCOPE)A way to probe caves on the moon from orbit. Using a concept called “photon time-of-flight imaging”, the researchers say they would be able to bounce the signal off of the walls of the canyon to peer into the crevice and see what is there.

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Plasma bombs, powerful tornadoes, and supersonic jets may be the start of the solar wind.

Plasma bombs, powerful tornadoes, and supersonic jets may be the start of the solar wind. | Amazing Science | Scoop.it

The first detailed view of a poorly understood region of the Sun reveals plasma 'bombs', powerful tornadoes, and supersonic jets that may be the start of the solar wind. These observations, reported in five papers in the journalScience, will help scientists determine how massive amounts of energy generated by the Sun are transported from its surface to its outer atmosphere.


The features were detected by NASA's new IRIS space telescope, which studies the mysterious interface region that sits between the Sun's surface (photosphere) and the outer atmosphere (corona).


"IRIS's findings tell us the interface region of the Sun is far more complicated than we imagined," says Dr Hui Tian of the Harvard-Smithsonian Centre for Astrophysics, who is an author on four of the papers. The interface region is composed of the chromosphere and a transition layer between the chromospheres and corona.


"It's not the thin static layer predicted in solar atmospheric models. There's a sharp temperature change from the 6000-degree photosphere to the corona where temperatures reach over a million degrees, and the interface region is where this change occurs," says Tian. The region emits mostly ultraviolet light, which can be best studied in high resolution detail from space.


Using imaging and spectrometry, IRIS traces temperature differences within the chromosphere, as well as the speed, density and turbulence of dynamic plasma particles.


Tian and colleagues used IRIS to observe activity inside coronal holes where they discovered high-speed jets that may contribute plasma to the solar wind, the stream of particles constantly flowing from the Sun, which generates space weather on Earth.

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First Photos of Water Ice on Mercury Captured by NASA Spacecraft

First Photos of Water Ice on Mercury Captured by NASA Spacecraft | Amazing Science | Scoop.it

The first-ever photos of water ice near Mercury's north pole have come down to Earth, and they have quite a story to tell.


The images, taken by NASA's MESSENGER spacecraft (short for MErcury Surface, Space ENvironment, GEochemistry, and Ranging), suggest that the ice lurking within Mercury's polar craters was delivered recently, and may even be topped up by processes that continue today, researchers said.


More than 20 years ago, Earth-based radar imaging first spotted signs of water ice near Mercury's north and south poles — a surprise, perhaps, given that temperatures on the solar system's innermost planet can top 800 degrees Fahrenheit (427 degrees Celsius). [Water Ice On Mercury: How It Was Found (Video)]

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Hungry black hole eats 10 times faster than thought possible

Hungry black hole eats 10 times faster than thought possible | Amazing Science | Scoop.it

Astronomers have discovered a black hole that is consuming gas from a nearby star 10 times faster than previously thought possible. The black hole—known as P13—lies on the outskirts of the galaxy NGC7793 about 12 million light years from Earth and is ingesting a weight equivalent to 10 billion billion pounds every minute. The discovery was published today in the journal Nature.


International Centre for Radio Astronomy Research astronomer Dr Roberto Soria, who is based at ICRAR’s Curtin University node, said that as gas falls towards a black hole it gets very hot and bright. He said scientists first noticed P13 because it was a lot more luminous than other black holes, but it was initially assumed that it was simply bigger.


“It was generally believed the maximum speed at which a black hole could swallow gas and produce light was tightly determined by its size,” Dr Soria said. “So it made sense to assume that P13 was bigger than the ordinary, less bright black holes we see in our own galaxy, the Milky Way.”


When Dr Soria and his colleagues from the University of Strasbourg measured the mass of P13 they found it was actually on the small side, despite being at least a million times brighter than the Sun. It was only then that they realized just how much material it was consuming.


There’s not really a strict limit like we thought, black holes can actually consume more gas and produce more light,” Dr Soria said.

Dr. Soria said P13 rotates around a supergiant ‘donor’ star 20 times heavier than our own Sun.

He said the scientists saw that one side of the donor star was always brighter than the other because it was illuminated by X-rays coming from near the black hole, so the star appeared brighter or fainter as it went around P13.


“This allowed us to measure the time it takes for the black hole and the donor star to rotate around each other, which is 64 days, and to model the velocity of the two objects and the shape of the orbit," Dr Soria said.  “From this, we worked out that the black hole must be less than 15 times the mass of our Sun.”


Dr Soria said P13 is a member of a select group of black holes known as ultraluminous X-ray sources. “These are the champions of competitive gas eating in the Universe, capable of swallowing their donor star in less than a million years, which is a very short time on cosmic scales,” he said.

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An Europa-Io Moon Sample Return Mission

An Europa-Io Moon Sample Return Mission | Amazing Science | Scoop.it

A short while ago the Obama Administration released its proposed budget for FY2015.  NASA’s budget (which is almost certainly subject to change by Congress as has been the case for decades) would stay essentially flat at $17.5 billion and Planetary Science would get nearly $1.3 billion or just $65 million less than what Congress approved for the current fiscal year.  Included in the budget is $15 million for continued studies of a mission to Jupiter’s moon, Europa, in the 2020s.  But instead of a full blown flagship-class mission, the Administration is proposing that the Europa mission have a cost target of under a billion dollars.  This is just a fraction of the cost of missions like the proposed $2.1 billion Europa Clipper currently under study which itself is a fraction of the cost of the earlier proposed $4.7 billion Europa Orbiter.  As the planetary science community scrambles to figure out how to meet such a tight budget cap to such a difficult-to-reach (but scientifically fascinating) target like Europa, I would like to make a suggestion: A sample return mission to Europa.


A little over a year ago, the popular space press was filled with a flurry of stories about a proposed, low-cost sample return mission to Saturn’s moon, Enceladus.  Proposed by a team led by Peter Tsou of Sample Exploration Systems in La Canada, California, the LIFE (Life Investigation For Enceladus) mission would have a spacecraft fly through the geyser plumes in Enceladus’ southern polar region and use an aerogel collector (of the same sort successfully employed by NASA in the Stardust mission to return samples of cometary dust in 2006) to secure samples of the plumes’ icy particles for return to the Earth where they could be studied in detail.  Earlier concepts of the LIFE mission also included sample collection of Saturn’s E-ring (believed to be generated by particles that escaped Enceladus’ geysers into orbit around Saturn) and even the atmosphere of Titan.  The proposed mission offers an affordable means of securing samples from the watery (potentially life-supporting) environment beneath this moon’s icy crust using readily available technology.


In a presentation made last June at the LCPM-10 conference at Caltech, Tsou and his team outlined their vision for their proposed Discovery-class LIFE mission [1]:  The 15-year LIFE mission would be launched in the early 2020s and employ a spacecraft with a ~800 kg dry mass possessing a ~3000 m/s Δv capability.  Assuming a storable, bipropellant propulsion system with a specific impulse of ~300 seconds like those typically used by other NASA planetary spacecraft, the launch mass would be something on the order of ~2,200 kg.  There are a number of possible mission profiles depending on the launch date and other factors, but in one proposed mission scenario, LIFE would be launched in November 2021 and use a VEEGA (Venus-Earth-Earth Gravity Assist) trajectory to gain the speed needed to reach Saturn using a smaller (and more affordable) launch vehicle.  The Venus flyby would take place in April 2022, the first Earth flyby would occur in March 2023 and the final Earth flyby in June 2026.  The spacecraft would then hibernate (to save on mission operation costs) until just before reaching Saturn in May 2030.


After entering orbit around Saturn, LIFE would use five close passes by Saturn’s largest moon, Titan, over the course of 128 days to gradually alter the probe’s orbit so that it could make multiple low-speed (3.7 to 4 km/s) passes through the geysers in the southern polar regions of Enceladus where an aerogel collector would secure samples of the plumes’ ice particles.  This is lower than Stardust’s 6.1 km/s encounter velocity with Comet Wild 2 in January 2006 and would result in better preservation of fragile ice particles.


After the encounters with Enceladus are completed, seven additional Titan flybys over 152 days would gradually pump up LIFE’s orbit in preparation for its departure.  After spending about two years in orbit around Saturn, LIFE would use its propulsion system to escape Saturn and begin the ~4.5 year long voyage back to Earth.  Sometime in late 2036, the return capsule would detach from the main spacecraft and reenter Earth’s atmosphere at a speed of 16 to 18 km/s.  The total Discovery-class mission cost would be about $425 million, excluding launch, and is advertised to generate flagship-class quality science on a Discovery-class budget.


References

[1] P. Tsou, D.E. Brownlee, C.P. McKay, A. Anbar, H. Yano, Nathan Strange, Richard Dissly and I Kanik, “Low Cost Enceladus Sample Return Mission Concept”, Low Cost Planetary Mission Conference – 10 (Pasadena, CA; June 18 – 20, 2013), 2013 (presentation)


[2] Lorenz Roth, Joachim Saur, Kurt D. Retherford, Darrell F. Strobel, Paul D. Feldman, Melissa A. McGrath and Francis Nimmo, “Transient Water Vapor at Europa’s South Pole”, Science, Vol. 343, No. 6167, pp. 171-174, January 10, 2014 (abstract)


[3] “Hubble Space Telescope Sees Evidence of Water Vapor Venting off Jovian Moon”, News Release No. STScI-2013-55, December 12, 2013 (press release)


[4] Mission Design Center Trajectory Browser, NASA Ames Research Center (web site)


[5] “Galileo”, in Janes Space Directory 2001-2002, David Baker (editor), pp. 457-461, Janes Information Group Ltd., 2001

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The impossible triple star KIC 2856960

The impossible triple star KIC 2856960 | Amazing Science | Scoop.it

There's news of an 'impossible' triple star system recently discovered by astronomers. One that 'defies known physics.' Needless to say, there's no need to abandon physics quite yet.


It all comes from a new paper being published in MNRAS titled "KIC 2856960: the impossible triple star." Despite the overly-hyped title, it is interesting work. It's based upon data gathered from the Kepler satellite, which looked at the brightness of stars over time looking for exoplanets. Kepler finds exoplanets via the transit method, where the brightness of a star can be seen to dip when a planet passes in front of it. But the method can also be used to study multiple star systems if they happen to have the right alignment. Just as a planet can cause a star to dip in brightness when it passes in front, one star passing in front of another can have a similar effect.


The team looked at the data from KIC 2856960, for which Kepler gathered data over 4 years. In the data we see a small dip in brightness about 4 times a day, and a larger dip every 204 days. From this, it looks like a close binary of smaller stars (with orbital periods of 0.26 days) orbiting a third star with a period of 204 days. So it is a fairly common triple star system. Not a big deal, move on to other data.


But this team wanted to determine some of the characteristics of this system, such as their exact orbits and masses, so they looked at the data in more detail. Determining the details of a system can be tricky. There are all sorts of things that can add to noise in your data, such as starspots and other stellar activity. This is why exoplanets are divided into confirmed planets and candidate planets. Once you've eliminated the noise you can, you try to match the observed fluctuations to particular orbits, and then see if those orbits are stable. Sometimes the results can be deceiving.


What the team found was that the more they looked at the data for KIC 2856960, the more confusing things got. At first glance it looks like a triple star system, but when they tested candidate orbits, none of them seemed to fit. Several of them kind of fit, but there was always some unexplained fluctuation in the data. So the team tried other models, and found a 4-star system that basically worked, but it required the orbits one binary system to be in exact resonance with the other, which seems highly unlikely.


In other words, the Kepler data is inconclusive. It could be a strange 4-star system, or it could be a triple-star system with something else buried in the data. We can't be certain at this point. This does not make KIC 2856960 an "impossible" system. There's no evidence that it is defying known physics, just that the data is odd and we don't understand it.

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NASA: Jupiter's Red Spot is Likely a Sunburn, Not a Blush

NASA: Jupiter's Red Spot is Likely a Sunburn, Not a Blush | Amazing Science | Scoop.it

The ruddy color of Jupiter's Great Red Spot is likely a product of simple chemicals being broken apart by sunlight in the planet's upper atmosphere, according to a new analysis of data from NASA's Cassini mission. The results contradict the other leading theory for the origin of the spot's striking color -- that the reddish chemicals come from beneath Jupiter's clouds.


The results are being presented this week by Kevin Baines, a Cassini team scientist based at NASA's Jet Propulsion Laboratory, Pasadena, California, at the American Astronomical Society's Division for Planetary Science Meeting in Tucson, Arizona.


Baines and JPL colleagues Bob Carlson and Tom Momary arrived at their conclusions using a combination of data from Cassini's December 2000 Jupiter flyby and laboratory experiments.


In the lab, the researchers blasted ammonia and acetylene gases -- chemicals known to exist on Jupiter -- with ultraviolet light, to simulate the sun's effects on these materials at the extreme heights of clouds in the Great Red Spot. This produced a reddish material, which the team compared to the Great Red Spot as observed by Cassini's Visible and Infrared Mapping Spectrometer (VIMS). They found that the light-scattering properties of their red concoction nicely matched a model of the Great Red Spot in which the red-colored material is confined to the uppermost reaches of the giant cyclone-like feature.


"Our models suggest most of the Great Red Spot is actually pretty bland in color, beneath the upper cloud layer of reddish material," said Baines. "Under the reddish 'sunburn' the clouds are probably whitish or grayish." A coloring agent confined to the top of the clouds would be inconsistent with the competing theory, which posits that the spot's red color is due to upwelling chemicals formed deep beneath the visible cloud layers, he said. If red material were being transported from below, it should be present at other altitudes as well, which would make the red spot redder still.

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ESA explores the concept of a 3D-printed moonbase

ESA explores the concept of a 3D-printed moonbase | Amazing Science | Scoop.it

The European Space Agency (ESA) is currently exploring the possibility of establishing a permanent lunar base with the aid of 3D printing technology. The space agency and Foster + Partners, the London-based architecture firm that worked closely with the agency in the exploration of the project, have released a video outlining how they envision a future mission to construct a moonbase may unfold.


Whilst the idea of a frontier settlement on Mars has captured the imagination of the general public, establishing a base on the Moon would be a much more attainable prospect and could even serve as a proving ground for a mission to the Red Planet.


For mankind to establish a permanent outpost beyond low-Earth orbit, certain safeguards are required to protect us from the harsh conditions that prevail beyond the defensive shield of our planet's atmosphere. On a body such as the Moon that only has a minimal atmosphere, an outpost would be exposed to a plethora of dangers including solar radiation and micro-meteoroid impacts.


To mitigate these dangers, ESA has been investigating the potential of using rover-like automatons to 3D print a moonbase around an inflatable habitat dome located at the lunar south pole. Previous experiments carried out by the agency and its partners have already demonstrated that 3D printing such an outpost is indeed viable with lunar materials.


The experiment used basaltic rock extracted from a volcano in central Italy to mimic the qualities of lunar soil with a fidelity of 99.8 percent. Using this material, the team printed a 1.5 tonne (1.7 ton) building block with a hollow closed-cell structure. It is hoped that such building blocks may one day be instrumental in creating a permanent outpost on the Moon.


"3D printing offers a potential means of facilitating lunar settlement with reduced logistics from Earth," states Scott Hovland of ESA’s Human Spaceflight Team. "The new possibilities this work opens up can then be considered by international space agencies as part of the current development of a common exploration strategy."


The process of transforming the "lunar" material into a usable building block began by mixing the basaltic rock with magnesium oxide. This created a paper-like substance that was then manipulated by a 6 m (20 ft) mobile printing array supplied by Monolite UK Ltd. The block was then built up layer by layer and sprayed with a salt-based binding solution that turned the sand-like construction rock hard.


Italian firm Alta SpA, working in conjunction with engineering university Scuola Superiore Sant'Anna, took the project one step further, examining how the terrestrial based 3D printing technique would fare in a vacuum. "The [3D printing] process is based on applying liquids but, of course, unprotected liquids boil away in vacuum," explains Giovanni Cesaretti of Alta. To remedy the issue, the team inserted nozzles distributing the binding solution inside the lunar soil, dispensing 2 mm droplets, small enough to bind the material without boiling away. ESA and its partners are now looking to refine the process, including exploring the possibility of using concentrated sunlight to melt the lunar material into a solid state, which would remove the need to use a binding solution.

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Oceans arrived early on Earth: Primitive meteorites were the likely source of water

Oceans arrived early on Earth: Primitive meteorites were the likely source of water | Amazing Science | Scoop.it

Earth is known as the Blue Planet because of its oceans, which cover more than 70 percent of the planet's surface and are home to the world's greatest diversity of life. While water is essential for life on the planet, the answers to two key questions have eluded us: Where did Earth's water come from and when? While some hypothesize that water came late to Earth, well after the planet had formed, findings from a new study significantly move back the clock for the first evidence of water on Earth and in the inner solar system.


"The answer to one of the basic questions is that our oceans were always here. We didn't get them from a late process, as was previously thought," said Adam Sarafian, the lead author of the paper published Oct. 31, 2014, in the journal Science and a MIT/WHOI Joint Program student in the Geology and Geophysics Department.


One school of thought was that planets originally formed dry, due to the high-energy, high-impact process of planet formation, and that the water came later from sources such as comets or "wet" asteroids, which are largely composed of ices and gases.


"With giant asteroids and meteors colliding, there's a lot of destruction," said Horst Marschall, a geologist at WHOI and coauthor of the paper. "Some people have argued that any water molecules that were present as the planets were forming would have evaporated or been blown off into space, and that surface water as it exists on our planet today, must have come much, much later -- hundreds of millions of years later."


The study's authors turned to another potential source of Earth's water -- carbonaceous chondrites. The most primitive known meteorites, carbonaceous chondrites, were formed in the same swirl of dust, grit, ice and gasses that gave rise to the sun some 4.6 billion years ago, well before the planets were formed. "These primitive meteorites resemble the bulk solar system composition," said WHOI geologist and coauthor Sune Nielsen. "They have quite a lot of water in them, and have been thought of before as candidates for the origin of Earth's water."


In order to determine the source of water in planetary bodies, scientists measure the ratio between the two stable isotopes of hydrogen: deuterium and hydrogen. Different regions of the solar system are characterized by highly variable ratios of these isotopes. The study's authors knew the ratio for carbonaceous chondrites and reasoned that if they could compare that to an object that was known to crystallize while Earth was actively accreting then they could gauge when water appeared on Earth.


To test this hypothesis, the research team, which also includes Francis McCubbin from the Institute of Meteoritics at the University of New Mexico and Brian Monteleone of WHOI, utilized meteorite samples provided by NASA from the asteroid 4-Vesta. The asteroid 4-Vesta, which formed in the same region of the solar system as Earth, has a surface of basaltic rock -- frozen lava. These basaltic meteorites from 4-Vesta are known as eucrites and carry a unique signature of one of the oldest hydrogen reservoirs in the solar system. Their age -- approximately 14 million years after the solar system formed -- makes them ideal for determining the source of water in the inner solar system at a time when Earth was in its main building phase. The researchers analyzed five different samples at the Northeast National Ion Microprobe Facility -- a state-of-the-art national facility housed at WHOI that utilizes secondary ion mass spectrometers. This is the first time hydrogen isotopes have been measured in eucrite meteorites.

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European satellite Gaia could discover thousands of planets in our Milky Way galaxy

European satellite Gaia could discover thousands of planets in our Milky Way galaxy | Amazing Science | Scoop.it
A recently launched European satellite could reveal tens of thousands of new planets within the next few years, and provide scientists with a far better understanding of the number, variety and distribution of planets in our galaxy, according to researchers.


Researchers from Princeton University and Lund University in Sweden calculated that the observational satellite Gaia could detect as many as 21,000 exoplanets, or planets outside of Earth's solar system, during its five-year mission. If extended to 10 years, Gaia could detect as many as 70,000 exoplanets, the researchers report. The researchers' assessment is accepted in the Astrophysical Journal and was published Nov. 6 in advance-of-print on arXiv, a preprint database run by Cornell University.


Exoplanets will be an important "by-product" of Gaia's mission, Perryman said. Built and operated by the European Space Agency (ESA) and launched in December 2013, Gaia will capture the motion, physical characteristics and distance from Earth -- and one another -- of roughly 1 billion objects, mostly stars, in the Milky Way galaxy with unprecedented precision. The presence of an exoplanet will be determined by how its star "wobbles" as a result of the planet's orbit around it.


More important than the numbers of predicted discoveries are the kinds of planets that the researchers expect Gaia to detect, many of which -- such as planets with multi-year orbits that pass directly, or transit, in front of their star as seen from Earth -- are currently difficult to find, explained first author Michael Perryman, an adviser on large scientific programs who made the assessment while serving as Princeton's Bohdan Paczyński Visiting Fellow in the Department of Astrophysical Sciences. The satellite's instruments could reveal objects that are considered rare in the Milky Way, such as an estimated 25 to 50 Jupiter-sized planets that orbit faint, low-mass stars known as red dwarfs. Unique planets and systems -- such as planets that orbit in the opposite direction of their companions -- can inspire years of research, Perryman said.


"It's not just about the numbers. Each of these planets will be conveying some very specific details, and many will be highly interesting in their own way," Perryman said. "If you look at the planets that have been discovered until now, they occupy very specific regions of discovery space. Gaia will not only discover a whole list of planets, but in an area that has not been thoroughly explored so far."

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I hope that this satellite could reveal the mystery of galaxy.

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The archaeology of space: In search for immortality of human civilization

The archaeology of space: In search for immortality of human civilization | Amazing Science | Scoop.it

LAGEOS - There is even a probe with such a purpose, its plaque meant not for extraterrestrials, but for the (equally alien) future inhabitants of Earth. The Laser Geodynamic Satellite, or LAGEOS, was launched in 1976 to facilitate the measurement of continental drift with a second LAGEOS set loose from the shuttle Columbia in 1992. The probe itself is a magnificent object, strikingly different from run-of-the-mill satellites, a ball of solid brass more than half a meter in diameter, weighing roughly 450 kg and dotted with reflectors like a large disco ball. LAGEOS carries no electronics or other instrumentation; ground stations aim lasers at its reflective surface, measuring the distance to detect tiny perturbations in the Earth’s crust. The probe’s great mass helps it achieve a supremely stable orbit without onboard propulsion; it will be 8.4 million years before its orbit decays, at which time it will come crashing through whatever atmosphere remains in the wake of the Anthropocene. The LAGEOS plaque, also conceived by Sagan, features maps of the Earth’s continents before and after the mission as well as at time of launch, spanning 16 million years of projected continental drift — permitting future Earthlings, human or nonhuman, to look at the disposition of the continents upon which they live and check our work.


Memory of Mankind project - Has an estimated lifespan of 100,000 years. They are storing information on inscribed stone tablets and storing them in a salt mine in Austria.


Rosetta Project - It's goal is to preserve around 13,000 pages of information in each of 1,500 languages on a disk made of nickel. The disk can be read with a microscope and is contained within a 4 inch spherical container. One of these disks is on the Rosetta spacecraft that was launched in March of 2004; although it's mission ends in 2015.


KEO space time capsule - Has experienced several delays and has not been launched yet. Estimated to launch in 2015. It's purpose is to reenter the Earth's atmosphere in 50,000 years. It will apparently carry around 24 billion pages of messages on a DVD with symbolic instructions for how to build a reader. It will also contain a drop of human blood and samples of air, sea water and earth encased in diamond.

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Terrestrial Return Vehicle to provide parcel post for the ISS

Terrestrial Return Vehicle to provide parcel post for the ISS | Amazing Science | Scoop.it

So much attention is paid to how to get into space that we often forget that getting back can be just as difficult. For example, getting experiment samples back from the International Space Station (ISS) is a logistical nightmare. Intuitive Machines' Terrestrial Return Vehicle (TRV) system may change that by making sending small payloads back to Earth as easy as mailing a parcel.


Getting samples back from the ISS currently means hitching a ride on a returning cargo or crew ferry craft, but this happens only a few times a year with every ounce already spoken for. That may be okay for most items, but what about the ones that can't wait?


The Terrestrial Return Vehicle (TRV) is a commercial service being developed by Intuitive Machines and NASA as part of a project under the Center for the Advancement of Science in Space (CASIS), which is responsible for installing the TRV on the space station and non-flight systems. It's designed to return small samples on demand from the ISS on the same day, and is suitable for critical and perishable materials that can't wait for the next ship home.


The TRV system is designed to be stored in the habitable volume of the ISS until required. When loaded up with its cargo, the TRV is placed in the Japanese Experiment Module (JEM) airlock, where the Cyclops ejection mechanism and the JEM Robotic Manipulator System are used to deploy it. Once released from the ISS, the TRV's guidance and propulsion systems take over and execute a controlled reentry maneuver before the craft's airfoil is deployed and it touches down at its designated spaceport.

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What does the next generation telescope need to detect life?

What does the next generation telescope need to detect life? | Amazing Science | Scoop.it

Almost 2,000 extrasolar planets have been discovered to date and this number is constantly increasing. Yet, we still know little about these alien worlds, especially their atmospheres. The atmospheres of terrestrial exoplanets could betray the presence of life on the planet, sparking NASA's interest in acquiring the spectra that appears as starlight shines through these planetary atmospheres.

A paper by Timothy Brandt and David Spiegel, exo-planetary scientists at the Institute for Advanced Study, Princeton, details what is needed in a next generation telescope for it to be capable of detecting signatures of life in the atmospheres of alien planets. The paper has been published in the September issue of the journal Proceedings of the National Academy of Sciences.

Astronomers employ several different methods to study the atmospheres of gas giants that orbit close to their host stars. One such method involves comparing the spectrum of a star when a planet is transiting across the surface to a spectrum when the planet is out of transit. By comparing the spectra, it is possible to see which elements exist in the planet's atmosphere.


Methods like this still can't be used for terrestrial planets, as the height of the atmosphere engulfing a rocky planet is miniscule compared to that of a gas giant. Earth-like planets also orbit their stars at a larger distance, making it even more difficult to observe their atmospheres.


Observations of terrestrial planet atmospheres will require a specialized space mission that will use a coronograph to block out the blinding light of the star. While the James Webb Space Telescope, due to launch in 2018, will be capable of detecting elements in planetary atmospheres, it will still be limited to more massive planets.


"Our paper is an attempt to better define the requirements for a mission capable of detecting oxygen and water," says Brandt. "This is NASA's target, assuming technology developments in coronagraphy and adaptive optics permit it."

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NASA: Frozen or Partially Liquid Ocean Inside Saturn's Moon Mimas?

NASA: Frozen or Partially Liquid Ocean Inside Saturn's Moon Mimas? | Amazing Science | Scoop.it

A new study focused on the interior of Saturn's icy moon Mimas suggests its cratered surface hides one of two intriguing possibilities: Either the moon's frozen core is shaped something like a football, or the satellite contains a liquid water ocean. Researchers used numerous images of Mimas taken by NASA's Cassini mission to determine how much the moon wobbles as it orbits Saturn. They then evaluated several possible models for how its interior might be arranged, finding two possibilities that fit their data.The study is published in the Oct. 17 issue of the journal Science.


"The data suggest that something is not right, so to speak, inside Mimas," said Radwan Tajeddine, a Cassini research associate at Cornell University, Ithaca, New York, and lead author on the paper. "The amount of wobble we measured is double what was predicted."


Either possiblity for the interior of Mimas would be interesting, according to Tajeddine, as the moon's heavily cratered outward appearance does not suggest anything unusual lies beneath its surface. Because Mimas formed more than four billion years ago, scientists would expect its core to have relaxed into a more or less spherical shape by now. So if Mimas' core is oblong in shape, it likely represents a record of the moon's formation, frozen in time.

If Mimas possesses an ocean, it would join an exclusive club of "ocean worlds" that includes several moons of Jupiter and two other Saturn moons, Enceladus and Titan. A global ocean would be surprising, said Tajeddine, as the surface of Mimas does not display signs of geologic activity.


Like a lot of moons in the solar system, including our own, Mimas always shows essentially the same face to its parent planet. This is called a spin-orbit resonance, meaning the moon's rotation, or spin, is in sync with its orbit around Saturn. Like Earth's moon, Mimas takes the same amount of time to spin completely around on its axis as it takes to orbit its planet.


The orbit of Mimas is very slightly stretched out, forming an ellipse rather than a perfect circle. This slight deviation causes the point on Mimas' surface that faces Saturn to vary a bit over the course of an orbit -- an observer on Saturn would see Mimas wobble slightly during its orbit, causing small amounts of terrain over the limb to become visible. This effect is called libration, and Earth's moon does it as well.


"Observing libration can provide useful insights about what is going on inside a body," said Tajeddine. "In this case, it is telling us that this cratered little moon may be more complex than we thought."

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NASA Prepares its Science Fleet for the Oct. 19th Mars Comet Encounter

NASA Prepares its Science Fleet for the Oct. 19th Mars Comet Encounter | Amazing Science | Scoop.it

NASA’s extensive fleet of science assets, particularly those orbiting and roving Mars, have front row seats to image and study a once-in-a-lifetime comet flyby on Sunday, Oct. 19, 2014.


Comet C/2013 A1, also known as comet Siding Spring, will pass within about 87,000 miles (139,500 kilometers) of the Red Planet -- less than half the distance between Earth and our moon and less than one-tenth the distance of any known comet flyby of Earth.


Siding Spring’s nucleus will come closest to Mars around 2:27 p.m. EDT, hurtling at about 126,000 mph (56 kilometers per second). This proximity will provide an unprecedented opportunity for researchers to gather data on both the comet and its effect on the Martian atmosphere.


“This is a cosmic science gift that could potentially keep on giving, and the agency’s diverse science missions will be in full receive mode,” said John Grunsfeld, astronaut and associate administrator for NASA’s Science Mission Directorate in Washington. “This particular comet has never before entered the inner solar system, so it will provide a fresh source of clues to our solar system's earliest days.”


Siding Spring came from the Oort Cloud, a spherical region of space surrounding our sun and occupying space at a distance between 5,000 and 100,000 astronomical units.  It is a giant swarm of icy objects believed to be material left over from the formation of the solar system.


Siding Spring will be the first comet from the Oort Cloud to be studied up close by spacecraft, giving scientists an invaluable opportunity to learn more about the materials, including water and carbon compounds, that existed during the formation of the solar system 4.6 billion years ago.

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Desktop sonic black hole emits Hawking radiation

Desktop sonic black hole emits Hawking radiation | Amazing Science | Scoop.it

A model black hole that traps sound instead of light has been caught emitting quantum particles, thought to be the analogue of the theoretical Hawking radiation. The effect may be the first time that a lab-based black hole has created Hawking particles in the same way expected from real black holes.


Black holes are ultra-dense concentrations of matter left behind when a star or other massive body collapses. Their gravity is so strong that nothing, not even light, can escape from their edge – a boundary called the event horizon.


Given that, physicists expected that black holes would be, well, black. But in 1974, Stephen Hawking of the University of Cambridge predicted they should emit a faint glow of particles now known as Hawking radiation.


An oddity of quantum theory that says that the vacuum of space is not truly empty, but fizzes with pairs of particles and their antimatter counterparts. Normally, these pairs annihilate each other and disappear. But if one gets caught inside a black hole's event horizon, the other is free to escape and becomes observable as Hawking radiation.


The glow from real-life black holes would be too faint to see so, to confirm Hawking's prediction, physicists have built artificial black holes that mimic the event horizon.


In 2009 Jeff Steinhauer at the Technion-Israel Institute of Technology in Haifa and his colleagues made just such a model black hole using Bose-Einstein condensates (BECs), a quantum state of matter where a clump of super-cold atoms behaves like a single atom.


Now, the team claims that their black hole has produced just the kind of Hawking radiation expected of a real black hole. "This tells us that the idea of Hawking actually works," Steinhauer says. "A black hole should really produce Hawking radiation."


The team used one laser to confine the BEC to a narrow tube, and another to accelerate some of it faster than the speed of sound. This fast flow created two horizons: an "outer" one at the point where the flow became supersonic, and an "inner" one further on where the flow slowed down again.


The Hawking effect comes from quantum noise at the horizon, says William Unruh at the University of British Columbia in Canada, one of the first to propose fluid-based black hole analogues. The horizons create pairs of particles of sound, or phonons. One phonon escapes the horizon, and the other is trapped inside it. A single phonon is too weak to observe, but the phonons inside the black hole bounce back and forth between the inner and outer horizons, triggering the creation of more Hawking phonons each time, much like a laser amplifies light. Physicists call this effect a black hole laser.


"The Hawking radiation exponentially grows, it self-amplifies," Steinhauer says. "That allows me to observe it, because the amplitude has grown." In the future he hopes to improve his detectors to sense radiation from a single horizon, which could help determine whether the pairs of phonons are entangled – another predicted feature of real black holes that may have fiery consequences.

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First ultraluminous pulsar found: NuSTAR discovers impossibly bright dead star with energy release of 10 million suns

First ultraluminous pulsar found: NuSTAR discovers impossibly bright dead star with energy release of 10 million suns | Amazing Science | Scoop.it

Astronomers working with NASA's Nuclear Spectroscopic Telescope Array (NuSTAR), led by Caltech's Fiona Harrison, have found a pulsating dead star beaming with the energy of about 10 million suns. The object, previously thought to be a black hole because it is so powerful, is in fact a pulsar—the incredibly dense rotating remains of a star.

"This compact little stellar remnant is a real powerhouse. We've never seen anything quite like it," says Harrison, NuSTAR's principal investigator and the Benjamin M. Rosen Professor of Physics at Caltech. "We all thought an object with that much energy had to be a black hole."


Dom Walton, a postdoctoral scholar at Caltech who works with NuSTAR data, says that with its extreme energy, this pulsar takes the top prize in the weirdness category. Pulsars are typically between one and two times the mass of the sun. This new pulsar presumably falls in that same range but shines about 100 times brighter than theory suggests something of its mass should be able to.


"We've never seen a pulsar even close to being this bright," Walton says. "Honestly, we don't know how this happens, and theorists will be chewing on it for a long time." Besides being weird, the finding will help scientists better understand a class of very bright X-ray sources, called ultraluminous X-ray sources (ULXs).


Harrison, Walton, and their colleagues describe NuSTAR's detection of this first ultraluminous pulsar in a paper that appears in the current issue of Nature.


"This was certainly an unexpected discovery," says Harrison. "In fact, we were looking for something else entirely when we found this."

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Milky Way's amount of Dark Matter is 800,000,000,000 times the mass of our Sun

Milky Way's amount of Dark Matter is 800,000,000,000 times the mass of our Sun | Amazing Science | Scoop.it
A new measurement of dark matter in the Milky Way has revealed there is half as much of the mysterious substance as previously thought.


Australian astronomers used a method developed almost 100 years ago to discover that the weight of dark matter in our own galaxy is 800,000,000,000 (or 8 x 1011) times the mass of the Sun. They probed the edge of the Milky Way, looking closely, for the first time, at the fringes of the galaxy about 5 million billion kilometres from Earth.


Astrophysicist Dr Prajwal Kafle, from The University of Western Australia node of the International Centre for Radio Astronomy Research, said we have known for a while that most of the Universe is hidden.

"Stars, dust, you and me, all the things that we see, only make up about 4 per cent of the entire Universe," he said.


"About 25 per cent is dark matter and the rest is dark energy." Dr Kafle, who is originally from Nepal, was able to measure the mass of the dark matter in the Milky Way by studying the speed of stars throughout the galaxy, including the edges, which had never been studied to this detail before.


He used a robust technique developed by British astronomer James Jeans in 1915 -- decades before the discovery of dark matter. Dr Kafle's measurement helps to solve a mystery that has been haunting theorists for almost two decades.


"The current idea of galaxy formation and evolution, called the Lambda Cold Dark Matter theory, predicts that there should be a handful of big satellite galaxies around the Milky Way that are visible with the naked eye, but we don't see that," Dr Kafle said.


"When you use our measurement of the mass of the dark matter the theory predicts that there should only be three satellite galaxies out there, which is exactly what we see; the Large Magellanic Cloud, the Small Magellanic Cloud and the Sagittarius Dwarf Galaxy."

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