23 Feb 2017

EXCLUSIVE: NASA’s Last Discovery Observed from Morocco

exclusive-nasa’s-last-discovery-observed-from-moroccoNASA’s last discovery of seven Earth-size planets that could potentially harbour life came out of a crucial collaboration with the Observatory of Oukaimeden, near Marrakech in Morocco.
 
“Thanks to NASA’s Spitzer satellite installed in Oukeimeden and the dozens of observatories involved, we were able to determine the existence of seven planets,” Zouhair Benkhaldoun, the director of the observatory, proudly told Morocco World News.

The scientist explained that the observation project started four years ago when the Origins in Cosmology and Astrophysics group (OrCA), from Beligan University of Liège contacted Cadi Ayyad University to collaborate on a “research initiative concerning exoplanets.”

In terms of this partnership, the University of Liège installed the TRAPPIST North telescope, dedicated to the observation of exoplanets, at Oukaimeden in May 2016.

Then the Observatory contacted NASA asking it to steer the Spitzer Space Telescope (SST) on the observation system, added Benkhaldoun.

It was through the SST that this major discovery, detected by the OrCA group, was made possible.

“The results of the observation of the planets were scanned by Khalid Berkaoui, a second year doctorate student at Cadi Ayyad University,” said Benkhaldoune, adding that himself and Berkaoui are co-authors of the study on the discovered planets, which will appear in the journal Nature on February 23.

It is not the first time when the Observatory of Oukaimeden has established a discovery. It already made, indeed, several discoveries of small bodies of the solar system: four comets and five Near-Earth Asteroids.

“What you should know is that the Laboratory of Physics of High Energy and Astrophysics of Cadi Ayyad University is ranked first in terms of scientific production in Morocco,” explained the Moroccan scientist.

“We have a community of very enthusiastic young people taking interest in astronomy. The future can only be promising,” he concluded.

Sun-gazers in Tamil Nadu preserve century-old tradition

aa-Cover-d5ccijur5gg5bjdfv5obic4dq6-20170223140433_MediIn the early morning darkness, Devendran P. walks up a hill to a solar observatory in the southern hill town of Kodaikanal, trudging the same path his father and grandfather walked in a century-old family tradition of studying the sun.

Once inside, he pulls a rope to open shutters in the dome and positions a six-inch telescope used since 1899 to photograph the sun and preserve a daily record of its activity.

"The sun, like stars, has a lifetime of 10 billion years," Devendran said. "If you want to know about any small changes, you need to have a large amount of data."

The observatory, run by the Indian Institute of Astrophysics, has a key role in providing a continuous stream of data on the sun and its influence on Earth and surrounding space, said R. Ramesh, a professor at the institute. 

"Some of the discoveries made, based on data obtained in the Kodaikanal observatory, are so fundamental to solar physics that they vastly improved techniques used at observatories even today," Ramesh said.

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In the observatory library, shelves stretch to the ceiling, packed with volumes of handwritten records and thousands of film plates of the sun. Authorities have launched a project to digitise and preserve the data collected over the past century.

Devendran's grandfather, Parthasarathy, joined the observatory in 1900, a year after it relocated from Chennai, the state capital, to Kodaikanal, situated more than 6,562 feet above sea level, offering ideal weather to study the sun.

Like his father and grandfather, Devendran has no formal education in astronomy. His interest was piqued during a visit to the observatory when he was a child.

He became a fulltime sun watcher in 1986 and says the six-inch ( telescope has never failed his family.

"It has never required any major overhaul, or change of parts, because we all take care of it," he said.

His 23-year-old son, Rajesh, expects to carry on the family tradition, but with one difference. He has a master's degree in physics.

"I get amazed by what my father does here," said Rajesh. "I think observing the Sun is in my blood."

Ultracool Dwarf and the Seven Planets

Astronomers have found a system of seven Earth-sized planets just 40 light-years away. Using ground and space telescopes, including ESO’s Very Large Telescope, the planets were all detected as they passed in front of their parent star, the ultracool dwarf star known as TRAPPIST-1. According to the paper appearing today in the journal Nature, three of the planets lie in the habitable zone and could harbour oceans of water on their surfaces, increasing the possibility that the star system could play host to life. This system has both the largest number of Earth-sized planets yet found and the largest number of worlds that could support liquid water on their surfaces.

Astronomers using the TRAPPIST–South telescope at ESO’s La Silla Observatory, the Very Large Telescope (VLT) at Paranal and the NASA Spitzer Space Telescope, as well as other telescopes around the world [1], have now confirmed the existence of at least seven small planets orbiting the cool red dwarf star TRAPPIST-1 [2]. All the planets, labelled TRAPPIST-1b, c, d, e, f, g and h in order of increasing distance from their parent star, have sizes similar to Earth [3].

Dips in the star’s light output caused by each of the seven planets passing in front of it — events known as transits — allowed the astronomers to infer information about their sizes, compositions and orbits [4]. They found that at least the inner six planets are comparable in both size and temperature to the Earth.

Lead author Michaël Gillon of the STAR Institute at the University of Liège in Belgium is delighted by the findings: “This is an amazing planetary system — not only because we have found so many planets, but because they are all surprisingly similar in size to the Earth!”

Comparing the TRAPPIST-1 planets

With just 8% the mass of the Sun, TRAPPIST-1 is very small in stellar terms — only marginally bigger than the planet Jupiter — and though nearby in the constellation Aquarius (The Water Carrier), it appears very dim. Astronomers expected that such dwarf stars might host many Earth-sized planets in tight orbits, making them promising targets in the hunt for extra-terrestrial life, but TRAPPIST-1 is the first such system to be found.

Co-author Amaury Triaud expands: “The energy output from dwarf stars like TRAPPIST-1 is much weaker than that of our Sun. Planets would need to be in far closer orbits than we see in the Solar System if there is to be surface water. Fortunately, it seems that this kind of compact configuration is just what we see around TRAPPIST-1!”

The team determined that all the planets in the system are similar in size to Earth and Venus in the Solar System, or slightly smaller. The density measurements suggest that at least the innermost six are probably rocky in composition.

The planetary orbits are not much larger than that of Jupiter’s Galilean moon system, and much smaller than the orbit of Mercury in the Solar System. However, TRAPPIST-1’s small size and low temperature mean that the energy input to its planets is similar to that received by the inner planets in our Solar System; TRAPPIST-1c, d and f receive similar amounts of energy to Venus, Earth and Mars, respectively.

All seven planets discovered in the system could potentially have liquid water on their surfaces, though their orbital distances make some of them more likely candidates than others. Climate models suggest the innermost planets, TRAPPIST-1b, c and d, are probably too hot to support liquid water, except maybe on a small fraction of their surfaces. The orbital distance of the system’s outermost planet, TRAPPIST-1h, is unconfirmed, though it is likely to be too distant and cold to harbour liquid water — assuming no alternative heating processes are occurring [5]. TRAPPIST-1e, f, and g, however, represent the holy grail for planet-hunting astronomers, as they orbit in the star’s habitable zone and could host oceans of surface water [6].

These new discoveries make the TRAPPIST-1 system a very important target for future study. The NASA/ESA Hubble Space Telescope is already being used to search for atmospheres around the planets and team member Emmanuël Jehin is excited about the future possibilities: “With the upcoming generation of telescopes, such as ESO’s European Extremely Large Telescope and the NASA/ESA/CSA James Webb Space Telescope, we will soon be able to search for water and perhaps even evidence of life on these worlds.”

Astronomers explain unusual dune-like patterns on comet 67P

Astronomers-explain-unusual-dune-like-patterns-on-comet-67PResearchers in France have explained the large dune-like patterns found on the surface of comet 67P/Churyumov-Gerasimenko.

Images collected by the now-retired Rosetta probe and its OIRIS camera revealed the presence of dune-like patterns on the comet's two lobes and the neck connecting them. Images of the same location, photographed at different times, showed the dunes are on the move.

Dune formation requires two ingredients: sediment grains and wind. Previous studies have proven comet 67P's surface to be covered in a layer of loose, dusty sediment.

Now, new research suggests temperature and pressure differences between the sunlit and shadowed sides of the comet are significant enough to drive dune-forming winds.

Comet 67P doesn't have a thick, stable atmosphere like Earth. It's atmosphere is thin and tenuous, formed by gases sublimated as the comet gets closer to the sun. Researchers at the French National Center for Scientific Research and the Laboratory of Physics and Mechanics of Heterogeneous Environments at the University of Paris determined pressure gradients on the comet are stark enough to power winds along 67P's surface. Because the comet's gravity is extremely weak, its tiny grains are much easier to transport.

Researchers published their analysis in the journal PNAS.

"Our understanding of the coupling between hydrodynamics and sediment transport is able to account for bed form emergence in extreme conditions and provides a reliable tool to predict the erosion and accretion processes controlling the evolution of small solar system bodies," researchers wrote in their paper.

22 Feb 2017

Astronomers observe black hole producing cold, star-making fuel from hot plasma jets and bubbles.

galaxy-center-phoenix-clusterThe Phoenix cluster is an enormous accumulation of about 1,000 galaxies, located 5.7 billion light years from Earth. At its centre lies a massive galaxy, which appears to be spitting out stars at a rate of about 1,000 per year. Most other galaxies in the universe are far less productive, squeaking out just a few stars each year, and scientists have wondered what has fuelled the Phoenix cluster’s extreme stellar output.

Now scientists from MIT, the University of Cambridge, and elsewhere may have an answer. In a paper published today in the Astrophysical Journal, the team reports observing jets of hot, 10-million-degree gas blasting out from the central galaxy’s black hole and blowing large bubbles out into the surrounding plasma.

These jets normally act to quench star formation by blowing away cold gas — the main fuel that a galaxy consumes to generate stars. However, the researchers found that the hot jets and bubbles emanating from the centre of the Phoenix cluster may also have the opposite effect of producing cold gas, that in turn rains back onto the galaxy, fuelling further starbursts. This suggests that the black hole has found a way to recycle some of its hot gas as cold, star-making fuel.

“We have thought the role of black hole jets and bubbles was to regulate star formation and to keep cooling from happening,” says Michael McDonald, assistant professor of physics in MIT’s Kavli Institute for Astrophysics and Space Research. “We kind of thought they were one-trick ponies, but now we see they can actually help cooling, and it’s not such a cut-and-dried picture.”

The new findings help to explain the Phoenix cluster’s exceptional star-producing power. They may also provide new insight into how supermassive black holes and their host galaxies mutually grow and evolve.

McDonald’s co-authors include lead author Helen Russell, an astronomer at Cambridge University; and others from the University of Waterloo, the Harvard-Smithsonian Center for Astrophysics, the University of Illinois, and elsewhere.

Hot jets, cold filaments

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The team analysed observations of the Phoenix cluster gathered by the Atacama Large Millimeter Array (ALMA), a collection of 66 large radio telescopes spread over the desert of northern Chile. In 2015, the group obtained permission to direct the telescopes at the Phoenix cluster to measure its radio emissions and to detect and map signs of cold gas.

The researchers looked through the data for signals of carbon monoxide, a gas that is present wherever there is cold hydrogen gas. They then converted the carbon monoxide emissions to hydrogen gas, to generate a map of cold gas near the centre of the Phoenix cluster. The resulting picture was a puzzling surprise.

“You would expect to see a knot of cold gas at the centre, where star formation happens,” McDonald says. “But we saw these giant filaments of cold gas that extend 20,000 light years from the central black hole, beyond the central galaxy itself. It’s kind of beautiful to see.”

The team had previously used NASA’s Chandra X-Ray Observatory to map the cluster’s hot gas. These observations produced a picture in which powerful jets flew out from the black hole at close to the speed of light. Further out, the researchers saw that the jets inflated giant bubbles in the hot gas.

When the team superimposed its picture of the Phoenix cluster’s cold gas onto the map of hot gas, they found a “perfect spatial correspondence”: The long filaments of frigid, 10-kelvins gas appeared to be draped over the bubbles of hot gas.

“This may be the best picture we have of black holes influencing the cold gas,” McDonald says.

Feeding the black hole

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What the researchers believe to be happening is that, as jet inflate bubbles of hot, 10-million-degree gas near the black hole, they drag behind them a wake of slightly cooler, 1-million-degree gas. The bubbles eventually detach from the jets and float further out into the galaxy cluster, where each bubble’s trail of gas cools, forming long filaments of extremely cold gas that condense and rain back onto the black hole as fuel for star formation.

“It’s a very new idea that the bubbles and jets can actually influence the distribution of cold gas in any way,” McDonald says.

Scientists have estimated that there is enough cold gas near the centre of the Phoenix cluster to keep producing stars at a high rate for another 30 to 40 million years. Now that the researchers have identified a new feedback mechanism that may supply the black hole with even more cold gas, the cluster’s stellar output may continue for much longer.

“As long as there’s cold gas feeding it, the black hole will keep burping out these jets,” McDonald says. “But now we’ve found that these jets are making more food, or cold gas. So you’re in this cycle that, in theory, could go on for a very long time.”

He suspects the reason the black hole is able to generate fuel for itself might have something to do with its size. If the black hole is relatively small, it may produce jets that are too weak to completely blast cold gas away from the cluster.

“Right now [the black hole] may be pretty small, and it’d be like putting a civilian in the ring with Mike Tyson,” McDonald says. “It’s just not up to the task of blowing this cold gas far enough away that it would never come back.”

The team is hoping to determine the mass of the black hole, as well as identify other, similarly extreme star makers in the universe.

21 Feb 2017

Astronomers Planning To Map Family Tree Of Stars In The Galaxy

evolutionary-tree-of-near-by-stars-constructed-using-the-genetic-code-mega-and-17-different-chemical-elements-as-the-stellar-dna

 A study is being conducted in a bid to find out the ancestry of stars and map their family tree. Researchers are using principles from biology and archaeology to build this "tree of Life" for stars.  ( Amanda Smith | Institute of Astronomy )

In 1859, Charles Darwin published his path breaking theory "Origin of Species," which detailed that every life form on Earth shares a common ancestor.

The theory has opened numerous avenues in the field of evolutionary biology since then. Now, astronomers are applying the same theory to find out about the history of stars.

Dr. Paula Jofré from the Institute of Astronomy of University of Cambridge is drawing on Darwin's theory and is set to create a phylogenetic "tree of life," which will link a collection of stars with one another in the galaxy.

"Phylogenetic trees add an extra dimension to our endeavours which is why this approach is so special. The branches of the tree serve to inform us about the stars' shared history," says Jofré.

Researchers are lending principles from biology and archaeology to build this "tree of life" for stars. By studying of the chemical signatures of the stars in the galaxy, the astronomers are putting the tree together to see how stars are formed and how they are connected to each other.

The chemical signatures are akin to DNA sequences found in life forms on Earth. The team has selected 22 stars, which also include the Sun of our solar system. The chemical signature of these 22 stars has been cautiously measured by using data obtained from ground-based high-resolution spectra, captured by telescopes placed in northern Chile.

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As soon as the data was analysed and families of the stars were identified by using their chemical DNA, researchers went on to study its evolution. The study was conducted based on the stars' ages and their kinematical properties, which was obtained from space mission Hipparcos.

Violent explosions occurring in the gas clouds, present in the galaxy produce stars. It is very much possible that two stars sharing similar chemical compositions may have been formed from the same gaseous molecular cloud.

Some stars survive the hardships of the universe and provide fossil records of the gas they were formed from. Among the stars evaluated at Institute of Astronomy, the oldest was estimated to have been formed about 10 billion years ago, while the youngest star in the group is 700 million years old.

Stars, like living organisms, share a history of ancestry as they carry with them the chemical structure of their origin I.e. the gas clouds from which they were formed. Astronomers can apply the same phylogenetic methods biologists use to map out the descent of plants and animals, to discover the "evolution" of stars.

Changes of supermassive black hole in the centre of NGC 2617 galaxy

ngc2617wideMembers of the Sternberg Astronomical Institute of the Lomonosov Moscow State University have been studying changes in the appearance of emission from around the supermassive black hole in the centre of a galaxy known to astronomers as NGC 2617. The centre of this galaxy, underwent dramatic changes in its appearance several years ago: it became much brighter and things that had not been seen before were seen. This sort of dramatic change can give us valuable information for understanding what the surroundings of a giant black hole are like and what is going on near the black hole. The results of these investigations have been published in the Monthly Notices of the Royal Astronomical Society, one of the world's top-rated astronomical journals.

Most galaxies such as our own have a giant black hole in their central nuclei. These monstrous holes have masses ranging from a million to a billion times the mass of our sun. The black hole in our galaxy is inactive, but in some galaxies, the black hole is swallowing gas that is spiralling into it and emitting enormous amounts of radiation. These galaxies are called "active galactic nuclei" or AGNs for short. The energy output from around the black holes of these AGNs can exceed that of the hundreds of billions of stars in the rest of the galaxy. Just how these galaxies get their supermassive black holes is a major mystery.

ngc 2617_SHARPEN projectsThe nuclei of galaxies where the supermassive black holes are vigorously swallowing gas are classified into two types: those where we get a direct view of the matter spiralling into the black hole at a speed that is thousands of times faster than the speed of sound, and those where the inner regions are obscured by dust and we only see more slowly moving gas much further from the black hole.

For decades astronomers have wondered why we see the innermost regions of some active galactic nuclei but not others. A popular explanation of the two types of active galactic nuclei is that they are really the same but they appear to be different to us because we are viewing them from different angles. If they are face-on we can see the hot gas spiralling into the black hole directly. If the active galactic nucleus is tilted, then dust around the nucleus blocks our view and we can only see the more slowly moving gas a light year or more away.

The leader of the international research team involved in the investigation, Viktor Oknyansky, a Senior Researcher at the Sternberg Astronomical Institute of the Lomonosov Moscow State University says: "Cases of object transition from one type to the other turn out to be a definite problem for this orientation model. In 1984 we found a change in the appearance of another active galactic nucleus known as NGC 4151. It was one of few known cases of this kind in the past. We now know of several dozen active galactic nuclei that have changed their type. In our recent study we have focused on one of the best cases -- NGC 2617."

Oknyansky continues: "In 2013 a team of researchers in the US found that NGC 2617 had changed being an active galaxy where the inner regions were hidden to one where the inner regions were now exposed. We didn't not know how long it would remain in this new unveiled state. It could last for only a short period of time or, on the other hand, for dozens of years. The title of the paper by the US astronomers was "The man behind the curtain..." When we began our study we didn't know how long the curtain would remain open, but we've titled our paper "The curtain remains open...", because we are continuing to see into the inner regions of NGC 2617.

According to the authors there is no accepted explanation so far of what could cause us to start seeing down to the inner regions of an active galactic nucleus when it was previously hidden.

untitledViktor Oknyansky comments: "It's clear that this phenomenon isn't very rare, on the contrary, we think it's quite typical. We consider various possible explanations. One is that perhaps a star has come too close to the black hole and has been torn apart. However, the disruption of a star by a black hole is very rare and we don't think that such events can explain the observed frequency of type changes of active galactic nuclei. Instead we favour a model where the black hole has started swallowing gas more rapidly. As the material spirals in towards the black holes it emits strong radiation. We speculate that this intense radiation destroys some of the dust surrounding the nucleus and permits us to see the inner regions."

Oknyansky continues: "Study of these rapid changes of type is very important for understanding what is going on around supermassive black holes that are rapidly swallowing gas. So, what we have concentrated on is getting observations of the various types of radiation emitted by NGC 2617. This has involved a large-scale effort."

The observational data for the project were obtained using the MASTER Global Robotic Network operated by Professor Vladimir Lipunov and his team, the new 2.5-m telescope located near Kislovodsk, a 2-m telescope of the observatory in Azerbajan, the Swift X-ray satellite, and some other telescopes. This research has been conducted in cooperation with colleagues from Azerbaijan, the USA, Finland, Chili, Israel and the South Africa.

Russian astronomers map out the heavens

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In late 1994 a star inside this galaxy exploded with such force that it momentarily eclipsed billions of other  
celestial bodies. Light from the explosion reached Earth.
   

Astronomers at Moscow State University (MGU) have created the world’s largest catalogue with information about 800 thousand galaxies.

The MGU catalogue includes every galaxy known to science. They are located within a radius greater than 30 billion light-years from our planet.

The catalogue details 800 thousand galaxies, their stellar composition and brightness in the electromagnetic spectrum - from ultraviolet to infrared. According to the researchers, the project was made possible thanks to big data.

The publicly available work is called the Reference Catalogue of Galaxy SEDs. Its analysis of emission lines and their shapes is more detailed and accurate than any other, say the scientists.

So far, the information collected pertains only to galaxies that are close (by cosmological standards), I.e. those with a red shift (a displacement in the spectral lines towards longer wavelengths when moving away from the observer) of no more than 0.3. There is less information about the early Universe. However, the astronomers plan to add a further 300-400 galaxies in the near future.

20 Feb 2017

NASA Scientists Have Proposed a New Definition for Planets, and It Could Change Everything

pluto-planet-stern_1024NASA scientists have published a manifesto that proposes a new definition of a planet, and if it holds, it will instantly add more than 100 new planets to our Solar System, including Pluto and our very own Moon.

The key change the team is hoping to get approved is that cosmic bodies in our Solar System no longer need to be orbiting the Sun to be considered planets - they say we should be looking at their intrinsic physical properties, not their interactions with stars.

"In keeping with both sound scientific classification and peoples' intuition, we propose a geophysical-based definition of 'planet' that importantly emphasises a body's intrinsic physical properties over its extrinsic orbital properties," the researchers explain.

The team is led by Alan Stern, principle investigator of NASA's New Horizons mission to Pluto, which in 2015 achieved the first-ever fly-by of the controversial dwarf planet. 

Pluto was famously 'demoted' to dwarf planet status back in August 2006, when astronomer Mike Brown from the California Institute of Technology (Caltech) proposed a rewrite of the definition of planets.

The International Astronomical Union (IAU), which controls such things, declared that the definition of a planet reads as follows:

"A celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit."

Having not yet cleared the neighbourhood of its orbit in space, Pluto could no longer hold the designation of a planet under these new guidelines.

02-moon-facts-graveyardStern, who obviously has a great fondness for Pluto, having led the mission that showed us all its adorable heart pattern for the first time, recently called the decision "bullshit".

"Why would you listen to an astronomer about a planet?" Stern, a planetary scientist, pointed out to Kelly Dickerson at Business Insider in 2015.

He said asking an astronomer, who studies a wide variety of celestial objects and cosmic phenomena, rather than a planetary scientist, who focusses solely on planets, moons, and planetary systems, for the definition of a planet is like going to a podiatrist for brain surgery.

"Even though they're both doctors, they have different expertise," Stern said. "You really should listen to planetary scientists that know something about this subject. When we look at an object like Pluto, we don't know what else to call it."

Now, Stern and his colleagues have rewritten the definition of a planet, and are submitting it to the IAU for consideration.

"We propose the following geophysical definition of a planet for use by educators, scientists, students, and the public," they write.

"A planet is a sub-stellar mass body that has never undergone nuclear fusion and that has sufficient self-gravitation to assume a spheroidal shape adequately described by a triaxial ellipsoid regardless of its orbital parameters."

If that's a little too jargony for you, their 'layman's version' is simply: "Round objects in space that are smaller than stars."

The definition sounds incredibly simple, but it's deceptively narrow - there aren't a whole lot of objects objects in the known Universe that would qualify, as it excludes things like stars and stellar objects such as white dwarfs, plus neutron stars and black holes.

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"In keeping with emphasising intrinsic properties, our geophysical definition is directly based on the physics of the world itself, rather than the physics of its interactions with external objects," the researchers explain.

This would mean that our Moon, and other moons in the Solar System such as Titan, Enceladus, Europa, and Ganymede, would all qualify as planets, as would Pluto itself, which has already been looking more and more 'planet-like' of late.

The researchers don't just argue that their definition holds more merit than the current one in terms of what properties we should be using to classify a planet - they say the current definition is inherently flawed for several reasons.

•"First, it recognises as planets only those objects orbiting our Sun, not those orbiting other stars or orbiting freely in the galaxy as 'rogue planets'," they explain.

•Second, the fact that it requires zone-clearing means "no planet in our Solar System" can satisfy the criteria, since a number of small cosmic bodies are constantly flying through planetary orbits - including Earth's.

•Finally, and "most severely", they say, this zone-clearing stipulation means the mathematics used to confirm if a cosmic body is actually a planet must be distance-dependent, because a "zone" must be clarified.

This would require progressively larger objects in each successive zone, and "even an Earth-sized object in the Kuiper Belt would not clear its zone".

Of course, nothing changes until the IAU makes a decision, and if it decides to rejig the definition of a planet, either by these recommendations or others in the future, it's going to take a whole lot of deliberating before it becomes official.

But the team claims to have the public on their side, and if this public debate is anything to go on, maybe it's time for a rethink - even if Stern just really wants to stop having to answer the question: "Why did you send New Horizons to Pluto if it's not a planet anymore?"

17 Feb 2017

Building blocks of life found on Ceres

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The terrain around crater Ernutet, as seen by Dawn. Warmer colours indicate the densest concentrations of organics. (Courtesy: NASA/JPL–Caltech/UCLA/ASI/INAF/MPS/DLR/IDA)

Organic compounds have been discovered on the surface of the dwarf-planet Ceres. The Visual and Infrared Spectrometer (VIR) on NASA's Dawn spacecraft detected the compounds while in orbit around the minor planet. The team investigating the data suggests that the organics were formed on Ceres, indicating the planet has a more complex chemical history than previously assumed.

The organics detected are aliphatic compounds – chain molecules primarily comprised of carbon and hydrogen atoms. They were found moving across the south-western floor of a 50 km-wide crater called Ernutet, as well as in patches to the crater's north-west. Organic compounds are volatile and would be easily destroyed by the intense heat of an asteroid impact. Also, their distribution across the surface does not seem to match with the ejecta from any specific crater.

The discovery was made by a team led by Maria Cristina De Sanctis of the National Institute of Astrophysics in Rome, during a survey of Ceres' surface between 60° north and 60° south. At higher latitudes the data was too noisy to be useful. "I've never seen anything like this anywhere in the solar system," De Sanctis told Physics World. "It's difficult to see how the organics could have come from an impactor."

If they were not delivered by an impactor, the organics must have somehow formed on Ceres itself. De Sanctis admits it is not certain whether they were made on the surface, or instead formed inside the dwarf planet before welling up from a water-rich layer below. Although all the raw materials for the organic compounds – carbon, hydrogen, nitrogen, phyllosilicates, water – are present on Ceres, "it is not very clear to me how the organics could have formed in situ,” says Thomas Prettyman of the Planetary Science Institute in Arizona.

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Sampling Ceres

Knowing exactly which aliphatic compounds are present would help to solve this puzzle, but they all have similar infrared emission lines centred around 3.4 μm, making it difficult for VIR to distinguish between different compounds. "We know for sure that they are organics, but we can't say what kind of organics," says De Sanctis.

"There could be several different types together, or just one At the comet 67P Churyumov–Gerasimenko, the European Space Agency's Rosetta mission was able to distinguish between organics because "the identification of specific molecules is best done by mass spectroscopy", says ESA's Michael Küppers. Rosetta was able to fly through the gaseous hood of the comet, called the coma, and sample organics directly with its mass spectrometer. Dawn does not have this option around Ceres.

Instead, team-member and Dawn's principal investigator, Christopher Russell from the University of California, Los Angeles, says that "the community is talking about a lander, which should be much easier to accomplish than landing on a larger body like Mars, and we know where the interesting sites on Ceres are."

Planetary designation

It's not the first time that organics have been found in the asteroid belt. Remote observations of several asteroids have hinted at the presence of organics, but it is unclear if they were deposited by impact or interplanetary dust. Meanwhile at the 92 km-wide Occator Crater on Ceres – home to bright patches of material known as "faculae" that are thought to be salt (possibly sodium carbonate) brought to the surface by water – there is an unidentified emission signature that could also be organics.

"What this discovery does is go beyond the wet-planet paradigm to Ceres being a possible incubator of more complex chemistry," says Russell. Although classified as a dwarf planet, Ceres is considered to be a protoplanet – the leftover hulk of a planet that never fully formed. Russell believes that the International Astronomical Union (IAU) misunderstood Ceres' nature when they promoted it to dwarf planet in 2006.

"The IAU chose to classify planetary status by size, which is flawed reasoning," he says. "Planetary designation should be judged on the interior properties instead. Ceres is a protoplanet or a small planet because of its internal chemistry. It did something besides just melting material, it made new [organic] material."

Although there is no suggestion of life on Ceres, aliphatic compounds ranging from methane and ethane to more complex compounds including kerite and asphaltite are thought to be essential building blocks of life's simplest biochemical mechanisms, making their discovery relevant to astrobiologists. "The presence of organics is a very important discovery," says Prettyman, before concluding that "it may be very challenging to determine their origins."

India government gives green light to go back to Mars then Venus

cc_mars_16x9The Indian Space Research Organisation (ISRO) may put a lander on Mars in 2021 or 2022 and send an orbiter to Venus shortly thereafter.

“The government has given us a go ahead for the planning of the missions,” ISRO Chairman A. S. Kiran Kumar in Bengaluru told Science Insider.

India was the first nation to successfully reach the Red Planet on its first attempt when the Mars Orbiter Mission (MOM), also known as Mangalyaan, entered orbit in 2014. The spacecraft continues to beam data back to mission control in Bengaluru; one of its stunning images of Mars graced the cover of last November’s issue of National Geographic. But the “technology demonstrator,” as ISRO calls MOM, has delivered only minimally on science expectations, critics say. For example, its methane sensor apparently has failed to detect methane plumes in the Martian atmosphere. “Mangalyaan was a marvel in engineering, but no exciting science came out of [it] since the experiments and instruments themselves were mediocre,” says U. R. Rao, chairman of ISRO’s science advisory committee and a former ISRO chief. “Small instruments give small science,” he says.

The Indian government gave the Mars reprise a green light in its 2017 budget proposal released this month. ISRO is promising a major science upgrade for its second mission, which it plans to undertake with France. "The next step has to be a lander. A lander on Mars is not easy, but it will be interesting to undertake," says Jean-Yves Le Gall, president of Centre National d'Études Spatiales (CNES), France’s space agency, in Paris.

ISRO is mulling whether to add a rover to what it’s provisionally calling “MOM II”; a final decision may hinge on the outcome of India’s next moon mission early next year, which will debut an Indian rover. If ISRO opts for a rover as part of MOM II, NASA is keen to offer its Electra radio equipment to facilitate communication between India’s rover and mission control, and to improve NASA’s communication with its Mars missions, says Michael M. Watkins, director of NASA’s Jet Propulsion Laboratory in Pasadena, California. He says NASA would also be open to working on a scientific instrument for MOM II’s payload if ISRO were interested. ISRO scientists caution, however, that the agency has not yet decided whether to go with a lander and rover, or play it safer with an orbiter carrying a more sophisticated set of scientific payloads than its predecessor. “The next mission has to have the best impact,” Kumar says.

ISRO’s internal discussions on a Venus mission, meanwhile, have just begun. One science objective, agency officials say, could be to study Venus’s carbon dioxide–rich atmosphere to glean insights into the build-up of the greenhouse gas in our planet’s atmosphere. Jacques Blamont, an astrophysicist and former CNES head who is professor emeritus at Pierre and Marie Curie University in Paris, told Science Insider that ISRO might wish to equip its orbiter with balloons carrying synthetic imaging radar; these could be launched into the Venusian atmosphere to study its properties and measure temperature fluctuations. “Venus is a terribly hot planet and no instrument survives for more than 30 to 60 minutes in its atmosphere, so making use of metallic balloons … is one possibility,” Rao says. That piques U.S. interest. Watkins says NASA “very possibly” may wish to collaborate on the Venus mission.

16 Feb 2017

Protostar displays a strange geometry

Using observations of molecules in the protostar L1527 taken by the ALMA observatory in northern Chile, a group of researchers has uncovered new clues to understanding how dust in a collapsing molecular cloud can shed angular momentum and penetrate beyond an area known as the 'centrifugal barrier' to find its way to the surface of the forming star.

170207191845_1_900x600_SHARPEN projectsOne of the big puzzles in astrophysics is how stars like the sun manage to form from collapsing molecular clouds in star-forming regions of the universe. The puzzle is known technically as the angular momentum problem in stellar formation. The problem essentially is that the gas in the star-forming cloud has some rotation, which gives each element of the gas an amount of angular momentum. As it collapses inward, eventually it reaches a state where the gravitational pull of the nascent star is balanced by the centrifugal force, so that it will no longer collapse inward of a certain radius unless it can shed some of the angular momentum. This point is known as the centrifugal barrier.

Now, using measurements taken by radio antennas, a group led by Nami Sakai of the RIKEN Star and Planet Formation Laboratory has found clues as to how the gas in the cloud can find its way to the surface of the forming star. To gain a better understanding of the process, Sakai and her group turned to the ALMA observatory, a network of 66 radio dishes located high in the Atacama Desert of northern Chile. The dishes are connected together in a carefully choreographed configuration so that they can provide images on radio emissions from protostellar regions around the sky.

The group chose to observe a protostar designated as L1527, located in a nearby star-forming region known as the Taurus Molecular Cloud. The protostar, located about 450 light years away, has a spinning protoplanetary disk, almost edge-on to our view, embedded in a large envelope of molecules and dust.

Previously, Sakai had discovered, from observations of molecules around the same protostar, that unlike the commonly held hypothesis, the transition from envelope to the inner disk -- which later forms into planets -- was not smooth but very complex. "As we looked at the observational data," says Sakai, "we realized that the region near the centrifugal barrier -- where particles can no longer in fall -- is quite complex, and we realized that analysing the movements in this transition zone could be crucial for understanding how the envelope collapses. Our observations showed that there is a broadening of the envelope at that place, indicating something like a "traffic jam" in the region just outside the centrifugal barrier, where the gas heats up as the result of a shock wave. It became clear from the observations that a significant part of the angular momentum is lost by gas being cast in the vertical direction from the flattened protoplanetary disk that formed around the protostar."

This behaviour accorded well with calculations the group had done using a purely ballistic model, where the particles behave like simple projectiles that do not need to be influenced by magnetic or other forces.

According to Sakai, "We plan to continue to use observations from the powerful ALMA array to further refine our understanding of the dynamics of stellar formation and fully explain how matter collapses onto the forming star. This work could also help us to better understand the evolution of our own solar system."

The research was published in the Monthly Notices of the Royal Astronomical Society published by Oxford University Press.

15 Feb 2017

Direct evidence of hierarchical assembly at low masses from isolated dwarf galaxy groups

s41550-016-0025-f1The current favourite model for the evolution of the universe, the Lambda Cold Dark Matter (LCDM) model, supports growth of cosmological structure via consolidation of smaller units. Widely referred to as ‘hierarchical’ assembly, this prescription posits that dark matter haloes as small as the size of our solar system act as the first seedlings that gradually grow up to be galaxies, galaxy groups and galaxy clusters. As a natural consequence of this picture, cosmological simulations predict a huge extant population of satellite structures surrounding the present-day structure at all scales that survived during the latter’s build-up process.

Shown above: A three-colour composite image of one of the observed groups, where red objects depict the individual member dwarf galaxies.

So, where are these satellites; have we seen them?

The answer, as it turns out, is yes and no. Observations have clearly elucidated that big galaxies such as our own Milky Way have several satellite- (or ‘dwarf’) galaxies surrounding them, as well as remnants of their destroyed building blocks in the form of stellar steams. On the other hand, despite predictions from theory and simulations, no satellites have been observed around the dwarfs themselves, nor have any dwarf galaxies been observed far away from big galaxies. Naturally, this has posed to be a discouraging evidence against the hierarchical build-up at small scales so far.

At the beginning of this year, Sabrina Stierwalt and her collaborators brought water to the thirsty by publishing the long-sought evidence of hierarchical structure formation at the low mass scale. In their paper, the authors reported direct observations of seven isolated, compact galaxy groups comprised solely of dwarf galaxies (see Figure 1). The discovery of these groups was made during a visual inspection of the most isolated dwarf galaxy pairs in the TiNy Titans survey (TNT), a multi-wavelength observational campaign that aims to investigate the effect of dwarf–dwarf interactions on the evolution of low-mass galaxies.

Even though they say seeing is believing, in astronomy, seeing something alone is rarely enough. In order to establish the identity of the objects the authors had seen as dwarf galaxy groups, they performed follow-up spectroscopy to confirm the association of the candidate dwarf galaxies with the visual groups in their images. Using the information about the groups’ projected sizes and velocity dispersions (see Figure 2), combined with the knowledge of typical dark matter content for dwarf galaxies, the authors performed dynamical mass calculations, the results of which imply that the observed associations are likely gravitationally bound structures.

s41550-016-0025-f2-213x300Left. Projected radial distance from the centroid of the group vs. difference in group member line-of-sight velocity from the group mean. The seven different symbols represent dwarfs belonging to the seven groups detected by the authors.

This isn’t the first time that associations of dwarf galaxies have come into the limelight. Previously made observations of the Milky Way dwarfs and their apparent proximity to the orbital plane of the the Large Magellanic Cloud have been argued to suggest that those dwarfs could be the result of a tidal breakup of the Magellanic group, of which the Magellanic Clouds were the largest (and brightest) members. Nonetheless, what makes the dwarf groups described by today’s authors in their paper truly unique relative to any previously known associations is their virtue of being highly compact and isolated. Being about an order of magnitude less extended than previous groups, and more than five million light years away from any massive neighbour, the TNT groups have the potential to serve as ideal labs for the study of structure build-up at small scales, unaffected by sensitive environmental effects such as ram pressure or tidal stripping that can otherwise erase the dynamical signatures of historically existing coherent structure.

The discovery of TNT dwarf groups provides a promising opportunity for the study of hierarchical assembly at low mass scales. However, mis-judgement of information sprouting up due to the completeness effect, and a bias towards detection of bright galaxies are possible in this study. Given that the brightest members of the reported groups are rather large, this study keeps the story of hierarchical formation at typical dwarf and satellite galaxy masses (I.e., very low mass-scales) yet a mystery. Future observations of even fainter galaxies and substructure in these groups will boost the census of dwarf galaxies to a statistically significant level, providing stronger grounds to tune our understanding of how structure forms in this elusive universe of ours.

Asteroid Day warns of threat to Earth

tunguska1As if you weren't already aware, Asteroid Day on June 30 gives researchers an opportunity to remind us of the dangers of celestial bodies hurtling into our midst here on Earth.

"Asteroids are scientific goldmines telling us about the history and dynamics of our solar system. But they also sometimes collide with Earth," Ed Lu, a former astronaut and CEO of Asteroid Day co-founder the B612 Foundation, said on Tuesday.

Asteroid Day is designed to draw attention to this rare yet potentially disastrous occurrence. The UN General Assembly recognised it as an official UN event to be held internationally every June 30.

The date is no coincidence. It marks the anniversary of the largest asteroid impact in recent history, the 1908 Tunguska event. The impact flattened around 2,000 square kilometres of uninhabited forest in Siberia.

"We know that asteroids pose risks to Earth and recent advances in sensor technology have radically improved our ability to detect and deflect these near-Earth objects," Britain's Astronomer Royal Martin Rees said.

One of Asteroid Day's more famous co-founders is Queen guitarist Brian May, who, when not pumping out quality space rock, busies himself by promoting awareness of space rocks.

The English rock star also holds a PhD in astrophysics. "On the heels of the United Nations announcement, the momentum for Asteroid Day is increasing exponentially around the world," he said.

Boise State professor helps discover two new planets

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Brian Jackson, an assistant professor in Boise State’s physics department, is also a leader of a consortium known as “SuPerPiG,” aka the “Short Period Planets Group.”

The group, which is funded by NASA to find planets that orbit for very short time periods very close to their host stars, is celebrating a success. The group found and confirmed two new planets that have been officially recognized by scientists at the Infrared Processing and Analysis Center at CalTech.

“Over the last few decades, astronomers have found planets in almost every nook and cranny that they can inhabit,” said Jackson in a statement. “These ultra-short-period planets are another example of the surprisingly wide variety of planets in our galaxy and may help us to understand the origins and early histories of planetary systems like our own.”

In his blog, Jackson wrote that the group found the planets by looking for their shadows as the passed in front of their host stars, a method for planet hunting known as the “transit method.”

According to Jackson, the new planets are both bigger than Earth but smaller than Neptune. The planets are both closer to their sun than any of the planets in our solar system.

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The new planets have names: The first ultra-short-period planet has been assigned the name K2-106. It circles its star EPIC 220674823 every 13 hours. The second planet, K2-106 c, has a longer orbit around EPIC 220674823 — 13.3 days.

First, they’re both bigger than Earth but smaller than Neptune – planet b is 50% larger, and planet c is 2.5 times larger. They inhabit a strange nether-region of planets where they’re known as super-Earths or sub-Neptune's, planets somewhere between Earth and Neptune. The reason there’s no specific name for such planets is because astronomers don’t understand this new class of planet at all.

Second, both planets are MUCH closer to their Sun than the planets in our solar system. In fact, planet b is so close to its sun that it takes less time to orbit (14 hours) than all the playtime it took the Cubs to go from 3 games down to tying up the World Series. By comparison, planet c circles at the glacial pace of once every 13 days.

Another thing that’s interesting about our planets: they’re yet another system of with an ultra-short-period planet (USP) in which there is more than one planet, i.e. a multi-planet system. In fact, as we argue in our paper,  most of the known systems with ultra-short-period planets are probably multi-planet systems and that fact might help explain the origin of these chthonic.

Hubble could get another repair mission after all

Hubble in orbitThe Hubble Space Telescope has been orbiting Earth for more than a quarter century. It’s sent back some amazing photos during that time, while also expanding our knowledge of the universe. The telescope got its last maintenance sweep in 2009, but now there’s talk in the government of sending another to the 27 year-old telescope. Of course, that’s going to be tricky without a Space Shuttle.

Hubble was launched in 1990 with great fanfare, but astronomers quickly realized it wasn’t working correctly. A defect in the mirror resulted in blurry images of objects the telescope should have been able to see in crystal clarity. Astronauts repaired the telescope in 1993 by adding an instrument to correct for the lens aberration — essentially eyeglasses for Hubble. That was the first of five service missions that added new cameras, repaired gyroscopes, and replaced the batteries.

The last Hubble service mission was in 2009, prior to the end of Shuttle flights in 2011. Hubble has long outlived its original life span, and it’s due for replacement soon. The James Webb Space telescope is going to launch in the next few years, but Hubble could get a new lease on life with another service mission. This is still in the early stages, but officials think that private space firm Sierra Nevada could have a vehicle capable of going on a Hubble refurbishment mission.

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Sierra Nevada flies an unmanned “mini-shuttle” called the Dream Chaser, which it has developed over the course of the last several years. Dream Chaser is based on designs generated in the early days of the Shuttle program, as well as the Air Force’s X-37B space plane. An unmanned version of the Dream Chaser could be used for Space Station resupply missions as soon as 2018, but a Hubble service mission would require a manned flight.

Keeping Hubble operational would serve two purposes. First, it’s a hedge against potential issues with the Webb Telescope. Unlike Hubble, Webb will be positioned far away from Earth at the L2 Lagrange point. That’s a stable orbital location that keeps the Earth between the telescope and the sun. It will be too far away to service effectively, so making sure the Hubble works as a backup could be smart. There will also be limited time on the Webb Telescope for astronomers, so keeping some observations on Hubble could free up time for studies that can only be completed by the more powerful Webb Telescope.

There’s still a lot of design and testing that needs to be done before Dream Chaser can take astronauts into space. However, the craft was designed from the start to theoretically support a crew. It has also been put forward as a possible space ambulance for the ISS.

14 Feb 2017

Astronomers want to recruit smartphones to listen for fast radio bursts

Astronomers-want-to-recruit-smartphones-to-listen-for-fast-radio-burstsResearchers want to use cell phones to listen for fast radio bursts, or FRBs, high-energy pulses of radio waves lasting just a few milliseconds.

Since the first FRB was identified in 2007 from archival data collected by the Parkes radio dish in Australia in 2001, a total of 20 fast radio bursts have been identified. The bursts have been discovered by massive radio telescopes.
 

Only one has been traced to a place of origin, a faraway galaxy. Astronomers hypothesize FRBs are caused by mergers of relativistic objects. The dispersion of frequencies that make up the FRBs so far identified suggest they originate in faraway galaxies -- outside the Milky Way.

However, astronomers believe there's no reason why a fast radio burst couldn't occur within the boundaries of the Milky Way galaxy. If it did, researchers at Harvard University suggest, it would be powerful enough to be picked up by cell phones.

"The search for nearby fast radio bursts offers an opportunity for citizen scientists to help astronomers find and study one of the newest species in the galactic zoo," Avi Loeb of the Harvard-Smithsonian Center for Astrophysics, said in a news release.

The radio frequencies encompassing FRBs are similar to those used by broadband, cellular and other wireless networks. An array of smartphones running a special mobile application could operate as a massive radio observatory.

"An FRB in the Milky Way, essentially in our own back yard, would wash over the entire planet at once. If thousands of cell phones picked up a radio blip at nearly the same time, that would be a good sign that we've found a real event," added Dan Maoz, an astronomer from Tel Aviv University.

Though it's estimated around 100 FRBs may originate from outside the Milky Way every day, the best calculations estimate an FRB is likely to happen inside the Milky Way only once every 30 to 1,500 years.

Slooh astronomers catch comet breakup

Sky watchers using the online Slooh system for real-time broadcast of celestial images were among the first on February 12, 2017 to confirm that the nucleus of passing comet 73P/Schwassmann-Wachmann has split into at least two large pieces. Slooh members using the company’s telescopes in Chile were able to view the comet as it broke. Slooh astronomer Paul Cox said:

This seems to be the continuation of a process that was first witnessed in 1995, then again in 2006 …

Members will continue to monitor the comet live over the coming weeks – assuming the comet survives that long.

Comets are fragile, icy bodies that do sometimes break up as they pass nearest the sun that binds them in orbit, and comet 73P will reach its perihelion – or closest approach to the sun – on March 16, 2017.

In 2025, comet 73P will come within 31 million miles of the planet Jupiter, which has also been known to “chew up comets,” Slooh said, due to its intense gravitational field. Cox said:


It certainly feels like it’s only a matter of time before comet 73P is destroyed, disintegrating into a trail of cosmic dust.

Bottom line: Member of the online astronomy site Slooh – whose motto is space for everyone – caught the breakup on February 12, 2017 of comet 73P/Schwassmann-Wachmann. Visit live.slooh.com.

13 Feb 2017

In lucky break, Israeli astronomers catch first hours of supernova

Weizmann Institute scientist helps reconstruct explosion of star, whose light took 160 million years to reach earth. Location NGC7610 in Pegasus: RA 23h 19m 41.4s DEC +10d11m06s

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A long time ago, in a galaxy far away, a super-giant red star ended its life in a spectacular explosion known as a supernova.

The light from that event took 160 million years to reach Earth where, in a stroke of luck, robot telescopes scanning the night sky happened upon it on October 6, 2013. The classical type II supernova was discovered by Koichi Itagaki (Japan). 

On Monday, astronomers said the chance discovery allowed them to study the earliest phase of a supernova yet — just three hours after it erupted.

“We immediately knew that what we have in hand is extremely unique,” Ofer Yaron of the Weizmann Institute of Science in Israel, lead author of a study in the journal Nature Physics, told AFP.

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“We managed to observe this event when (it was) very young,” said Yaron, of the Institute’s Department of Particle Physics and Astrophysics.

The supernova was named SN 2013fs.

Scientists are keen to study the early phases of supernovae, seeking insights into the moments just before massive stars expire in such dramatic fashion.

But without knowing when and where in the vast universe a supernova will occur, they are rarely spotted before they are already several days old and most of the debris has dispersed.

Supernovae are normally observable over a time scale of about a year, but their peak brightness lasts between several days and several weeks, said Yaron.

Until recently, catching a supernova a week after detonation was considered early.

The light of massive stars and their explosions can take several millions or billions of years to reach Earth.

In the case of SN 2013fs, the light’s 160-million-year trip was snared by an automated scan by the Palomar Observatory near San Diego, California, which is constantly looking for new astrophysical events.

A human eye spotted the celestial anomaly in telescope readings soon afterwards, and alerted other astronomers and physicists to train their instruments on the event to determine its distance, composition, temperature and other traits.

Among others, spectroscopic measurements of the light intensity were obtained from the WM Keck Observatory in Hawaii, and UV and X-ray readings from NASA’s Swift satellite.

f111206dh35-e1437373385643Yaron and a team assembled the data to reconstruct a picture of the moments before the star’s dazzling demise.

They caught the event so early, said the scientists, they could still observe the presence of material expelled by the dying star in its final year of life, forming a dense shell around it.

This hinted at instability in the dying moments of the star, which they concluded had been a red supergiant.

The supernova it caused was a “regular” type, suggesting that “pre-supernova instabilities may be common among exploding massive stars,” the team wrote.

If massive stars are unstable in the months before they die, their structure may be different than assumed so far — something that has implications for modelling of the explosion process, said Yaron.

NASA chooses New Zealand site to test space telescope technologies

detection_bigUnited States space scientists are to test new technologies for a powerful space-based telescope in an high-altitude balloon flight from New Zealand's South Island.

The NASA space agency confirmed Monday it would launch a long-duration, heavy-lift super pressure balloon (SPB) from the town of Wanaka for the third year running.

The launch, planned for late March or early April, would send the 532,000-cubic-meter SPB into what it described as "one of the most dynamic and severe flight regimes inside the Earth's atmosphere."

The balloon would ascend to an altitude of 33.5 km, where the stratospheric winds will propel it on a weeks-long journey around the Southern Hemisphere.

"With 32 days of flight in 2015 and 46 days in 2016, we hope to build on the successes and lessons learned of our past campaigns as we seek even longer duration flights at mid-latitudes," NASA balloon program office chief Debbie Fair brother said in a statement.

The balloon, which is as big as a sports stadium, would fly the University of Chicago's Extreme Universe Space Observatory (EUSO-SPB), a high-energy cosmic ray particle astrophysics payload.

The EUSO-SPB would test a fluorescence detector and supporting technologies in a precursor for a mission being planned to launch the EUSO telescope and install it on the International Space Station.

The balloon is made from polyethylene film, similar in appearance and thickness to the type used for sandwich bags, but stronger and more durable.

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The SPB was designed to float at a constant density altitude despite the heating and cooling of the day-night cycle.

The current record for a NASA super pressure balloon flight was 54 days.

Wanaka Airport operations manager Ralph Fegan said Monday that NASA had committing to the site as one of its global launch bases for up to 10 years.

The agreement had paved the way for NASA to invest in a longer term base of operations and to create a dedicated balloon launch pad, Fegan said in a statement.

JEM-EUSO is a new type of observatory that uses the earth's atmosphere as a detector. JEM-EUSO will be on orbit on the International Space Station (ISS). It observes transient luminous phenomena taking place in the earth's atmosphere caused by particles coming from space. The sensor is a super wide-field telescope that detects extreme energy particles with energy above 3×1019 eV. This remote-sensing instrument orbits around the earth every 90 minutes on board of the International Space Station at the altitude of approximately 400km (Figure 1-1). The figure shows an extreme energy particle colliding with a nucleus in the earth's Atmosphere, where it produces an Extensive Air Shower (EAS), consisting of numerous electrons, positrons, and photons. JEM-EUSO captures the moving track, which is revealed by the fluorescent UV photons and reproduces the energy development of the EAS.

top_euso_imgThe JEM-EUSO telescope has a super-wide Field-of-View (±30°) with two double sided curved Fresnel lenses and records the track of an EAS with a time resolution of 2.5 microseconds and a spatial resolution of about 0.75 km (corresponding to 0.1 degrees). These time-segmented images allow the determination of the energies and directions of the primary particles. The focal surface of the JEM-EUSO telescope is formed by about 6,000 multi-anode photomultipliers. The number of pixels is about two hundred thousand.

JEM-EUSO instrument can reconstruct the incoming direction of the extreme energy particles with accuracy better than several degrees. It's observational aperture of the ground area is a circle with 250 km radius and its atmospheric volume above it with a 60-degree field-of-view is about 1 tera-ton or more. The target volume for upward neutrino events exceeds 10 tera-tons. The instantaneous aperture of JEM-EUSO is larger than the Pierre Auger Observatory by a factor of 50 - 250 when attached to ISS.

EUSO was originally selected by the European Space Agency (ESA) as a mission attached to the European Columbus module of the ISS. The phase-A study has been successfully completed in June 2004 under ESA. However, ESA postponed the start of phase-B, so Japanese and U.S. teams re-defined EUSO as a mission attached to the Japanese Experiment Module/ Exposure Facility (JEM/EF) of ISS. It was renamed as JEM-EUSO and started the preparation targeting the launch of 2013 in the framework of the second phase utilization of JEM/EF utilization.

JEM-EUSO reduces the threshold energy down to around 3×1019 eV and increases the effective area due to advances in technology and also the superior features of JEM/EF. The reduction in the threshold energy is realized by 1) new lens material and improved optical design, 2)detectors with higher quantum efficiency, 3) improved algorithm for the event trigger. The increase in effective area is realized by inclining the telescope from nadir which is named as tilted mode (figure1-3). In this tilted mode, the threshold energy gets higher since the mean distance to EAS and atmospheric absorption both increase. The first half of the mission lifetime is devoted to observe lower energy region in the nadir mode and second half of the mission to observe high energy region in the tilted mode. JEM-EUSO is planned to be attached to JEM/EF of ISS, which will be launched in FY 2016 by H2B rocket and conveyed by the HTV (H-II transfer Vehicle) to ISS.