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Friday, October 17, 2014

First 3D Map Of The Hidden Universe Provides Tantalizing Glimpse Of Backbone Of The Cosmic Web

A team led by astronomers from the Max Planck Institute for Astronomy has created the first three-dimensional map of the ‘adolescent’ Universe, just 3 billion years after the Big Bang. This map, built from data collected from the W. M. Keck Observatory, is millions of light-years across and provides a tantalizing glimpse of large structures in the ‘cosmic web’ – the backbone of cosmic structure.

Credit: Casey Stark (UC Berkeley) And Khee-Gan Lee (Mpia)

On the largest scales, matter in the Universe is arranged in a vast network of filamentary structures known as the ‘cosmic web’, its tangled strands spanning hundreds of millions of light-years. Dark matter, which emits no light, forms the backbone of this web, which is also suffused with primordial hydrogen gas left over from the Big Bang. Galaxies like our own Milky Way are embedded inside this web, but fill only a tiny fraction of its volume.

Now a team of astronomers led by Khee-Gan Lee, a post-doc at the Max Planck Institute for Astronomy, has created a map of hydrogen absorption revealing a three-dimensional section of the universe 11 billions light years away – the first time the cosmic web has been mapped at such a vast distance. Since observing to such immense distances is also looking back in time, the map reveals the early stages of cosmic structure formation when the Universe was only a quarter of its current age, during an era when the galaxies were undergoing a major ‘growth spurt’.

Credit: Casey Stark (UC Berkeley) And Khee-Gan Lee (Mpia)

The map was created by using faint background galaxies as light sources, against which gas could be seen by the characteristic absorption features of hydrogen. The wavelengths of each hydrogen feature showed the presence of gas at a specific distance from us. 

Combining all of the measurements across the entire field of view allowed the team a tantalizing glimpse of giant filamentary structures extending across millions of light-years, and paves the way for more extensive studies that will reveal not only the structure of the cosmic web, but also details of its function – the ways that pristine gas is funneled along the web into galaxies, providing the raw material for the formation of galaxies, stars, and planets.

Using the light from faint background galaxies for this purpose had been thought impossible with current telescopes – until Lee carried out calculations that suggested otherwise. To ensure success, Lee and his colleagues obtained observing time at Keck Observatory, home of the two largest and most scientifically productive telescopes in the world.

Although bad weather limited the astronomers to observing for only 4 hours, the data they collected with the LRIS instrument was completely unprecedented. “We were pretty disappointed as the weather was terrible and we only managed to collect a few hours of good data. But judging by the data quality as it came off the telescope, it was clear to me that the experiment was going to work,” said Max Plank’s Joseph Hennawi, who was part of the observing team.

“The data were obtained using the LRIS spectrograph on the Keck I telescope,” Lee said. “With its gargantuan 10m-diameter mirror, this telescope effectively collected enough light from our targeted galaxies that are more than 15 billion times fainter than the faintest stars visible to the naked eye. Since we were measuring the dimming of blue light from these distant galaxies caused by the foreground gas, the thin atmosphere at the summit of Mauna Kea allowed more of this blue light to reach the telescope and be measured by the highly sensitive detectors of the LRIS spectrograph. The data we collected would have taken at least several times longer to obtain on any other telescope.”

Their absorption measurements using 24 faint background galaxies provided sufficient coverage of a small patch of the sky to be combined into a 3D map of the foreground cosmic web. A crucial element was the computer algorithm used to create the 3D map: due to the large amount of data, a naïve implementation of the map-making procedure would require an inordinate amount of computing time. 

Fortunately, team members Casey Stark and Martin White (UC Berkeley and Lawrence Berkeley National Lab) devised a new fast algorithm that could create the map within minutes. "We realized we could simplify the computations by tailoring it to this particular problem, and thus use much less memory. A calculation that previously required a supercomputer now runs on a laptop", says Stark.

The resulting map of hydrogen absorption reveals a three-dimensional section of the universe 11 billions light years away – this is first time the cosmic web has been mapped at such a vast distance. Since observing to such immense distances is also looking back in time, the map reveals the early stages of cosmic structure formation when the Universe was only a quarter of its current age, during an era when the galaxies were undergoing a major ‘growth spurt’. 

The map provides a tantalizing glimpse of giant filamentary structures extending across millions of light-years, and paves the way for more extensive studies that will reveal not only the structure of the cosmic web, but also details of its function – the ways that pristine gas is funneled along the web into galaxies, providing the raw material for the formation of galaxies, stars, and planets.

The W. M. Keck Observatory operates the largest, most scientifically productive telescopes on Earth. The two, 10-meter optical/infrared telescopes near the summit of Mauna Kea on the Island of Hawaii feature a suite of advanced instruments including imagers, multi-object spectrographs, high-resolution spectrographs, integral-field spectroscopy and world-leading laser guide star adaptive optics systems.

The Low Resolution Imaging Spectrometer (LRIS) is a very versatile visible-wavelength imaging and spectroscopy instrument commissioned in 1993 and operating at the Cassegrain focus of Keck I. Since it has been commissioned it has seen two major upgrades to further enhance its capabilities: addition of a second, blue arm optimized for shorter wavelengths of light; and the installation of detectors that are much more sensitive at the longest (red) wavelengths. 

Each arm is optimized for the wavelengths it covers. This large range of wavelength coverage, combined with the instrument's high sensitivity, allows the study of everything from comets (which have interesting features in the ultraviolet part of the spectrum), to the blue light from star formation, to the red light of very distant objects. LRIS also records the spectra of up to 50 objects simultaneously, especially useful for studies of clusters of galaxies in the most distant reaches, and earliest times, of the universe.

Keck Observatory is a private 501(c) 3 non-profit organization and a scientific partnership of the California Institute of Technology, the University of California and NASA.



Contacts and sources:
Steve Jefferson
W. M. Keck Observatory

Khee-Gan Lee
Max Planck Institute for Astronomy

Earth’s Magnetic Field Could Flip Within A Human Lifetime

Imagine the world waking up one morning to discover that all compasses pointed south instead of north.

It’s not as bizarre as it sounds. Earth’s magnetic field has flipped – though not overnight – many times throughout the planet’s history. Its dipole magnetic field, like that of a bar magnet, remains about the same intensity for thousands to millions of years, but for incompletely known reasons it occasionally weakens and, presumably over a few thousand years, reverses direction.

Left to right, Biaggio Giaccio, Gianluca Sotilli, Courtney Sprain and Sebastien Nomade sitting next to an outcrop in the Sulmona basin of the Apennine Mountains that contains the Matuyama-Brunhes magnetic reversal. A layer of volcanic ash interbedded with the lake sediments can be seen above their heads. Sotilli and Sprain are pointing to the sediment layer in which the magnetic reversal occurred.
Photo by Paul Renne

Now, a new study by a team of scientists from Italy, France, Columbia University and the University of California, Berkeley, demonstrates that the last magnetic reversal 786,000 years ago actually happened very quickly, in less than 100 years – roughly a human lifetime.

“It’s amazing how rapidly we see that reversal,” said UC Berkeley graduate student Courtney Sprain. “The paleomagnetic data are very well done. This is one of the best records we have so far of what happens during a reversal and how quickly these reversals can happen.”

Sprain and Paul Renne, director of the Berkeley Geochronology Center and a UC Berkeley professor-in- residence of earth and planetary science, are coauthors of the study, which will be published in the November issue of Geophysical Journal International and is now available online.

Flip could affect electrical grid, cancer rates

The discovery comes as new evidence indicates that the intensity of Earth’s magnetic field is decreasing 10 times faster than normal, leading some geophysicists to predict a reversal within a few thousand years.

Though a magnetic reversal is a major planet-wide event driven by convection in Earth’s iron core, there are no documented catastrophes associated with past reversals, despite much searching in the geologic and biologic record. Today, however, such a reversal could potentially wreak havoc with our electrical grid, generating currents that might take it down.

And since Earth’s magnetic field protects life from energetic particles from the sun and cosmic rays, both of which can cause genetic mutations, a weakening or temporary loss of the field before a permanent reversal could increase cancer rates. The danger to life would be even greater if flips were preceded by long periods of unstable magnetic behavior.

“We should be thinking more about what the biologic effects would be,” Renne said.

Dating ash deposits from windward volcanoes

The new finding is based on measurements of the magnetic field alignment in layers of ancient lake sediments now exposed in the Sulmona basin of the Apennine Mountains east of Rome, Italy. The lake sediments are interbedded with ash layers erupted from the Roman volcanic province, a large area of volcanoes upwind of the former lake that includes periodically erupting volcanoes near Sabatini, Vesuvius and the Alban Hills.

Leonardo Sagnotti, standing, and coauthor Giancarlo Scardia collecting a sample for paleomagnetic analysis.


Italian researchers led by Leonardo Sagnotti of Rome’s National Institute of Geophysics and Volcanology measured the magnetic field directions frozen into the sediments as they accumulated at the bottom of the ancient lake.

Sprain and Renne used argon-argon dating, a method widely used to determine the ages of rocks, whether they’re thousands or billions of years old, to determine the age of ash layers above and below the sediment layer recording the last reversal. These dates were confirmed by their colleague and former UC Berkeley postdoctoral fellow Sebastien Nomade of the Laboratory of Environmental and Climate Sciences in Gif-Sur-Yvette, France.

Because the lake sediments were deposited at a high and steady rate over a 10,000-year period, the team was able to interpolate the date of the layer showing the magnetic reversal, called the Matuyama-Brunhes transition, at approximately 786,000 years ago. This date is far more precise than that from previous studies, which placed the reversal between 770,000 and 795,000 years ago.

“What’s incredible is that you go from reverse polarity to a field that is normal with essentially nothing in between, which means it had to have happened very quickly, probably in less than 100 years,” said Renne. “We don’t know whether the next reversal will occur as suddenly as this one did, but we also don’t know that it won’t.”

Unstable magnetic field preceded 180-degree flip

Whether or not the new finding spells trouble for modern civilization, it likely will help researchers understand how and why Earth’s magnetic field episodically reverses polarity, Renne said.

The ‘north pole’ — that is, the direction of magnetic north — was reversed a million years ago. This map shows how, starting about 789,000 years ago, the north pole wandered around Antarctica for several thousand years before flipping 786,000 years ago to the orientation we know today, with the pole somewhere in the Arctic.


The magnetic record the Italian-led team obtained shows that the sudden 180-degree flip of the field was preceded by a period of instability that spanned more than 6,000 years. The instability included two intervals of low magnetic field strength that lasted about 2,000 years each. 

Rapid changes in field orientations may have occurred within the first interval of low strength. The full magnetic polarity reversal – that is, the final and very rapid flip to what the field is today – happened toward the end of the most recent interval of low field strength.

Renne is continuing his collaboration with the Italian-French team to correlate the lake record with past climate change.


Contacts and sources:
By Robert Sanders,
UC Berkeley

Thursday, October 16, 2014

Could Another Ebola Patient Make It To The U.S., And How Effective Are Quarantine And Screening? Louisville Expert Explains

You could have a situation very easily where someone leaves another country and they have no symptoms and they maybe deny any exposure," warns professor Mark A. Rothstein, J.D., director of the University of Louisville’s Institute for Bioethics, Health Policy and Law and joint appointee in the School of Medicine and Brandeis School of Law. Professor Rothstein is considered a leading authority on the ethical, legal and social implications of genetics, privacy, health policy and employment law.

"The initial line of defense has to be public health officials in the countries most effected," says professor Rothstein. Especially when their citizens are attempting to leave.



What the United States can do, is to "support them with equipment and consultation," Rothstein continues, "but it's [the effected countries'] responsibility at the first instance."

And when those practices are not effective, professor Rothstein explains, "Our people need to step in on our end, and make sure that they don't come into the country...It takes a long time to get to the United States, and within that 20 hour period, they may begin to show symptoms or they remember some contacts that are effected."

"We need to be on top of it. We need to find those people, to identify them, if necessary to isolate or even quarantine."

Caution, Not Complacency, Vital To Ebola Prevention; Nova Southeastern Expert Explains

"We are probably not well prepared at all for any type of pandemic or any type of major epidemic," warns Dr. Cecilia Rokusek, assistant dean for education, planning and research at Nova Southeastern University's College of Osteopathic Medicine.

"From a 'public health,' personal perspective, we need to be prepared," Rokusek cautions.

"We develop complacency oftentimes as an American population. We think it's not going to effect us...That's the biggest challenge for those of us in healthcare," she says.

Hear more of Dr. Rokusek's comments in the video embedded to the right, and for media inquiries, contact the Nova Southeastern University media relations office.

Tuesday, October 14, 2014

Pyramid Like Structure On Comet 67P

Stunning close up detail focusing on a smooth region on the ‘base’ of the ‘body’ section of comet 67P/Churyumov-Gerasimenko. The image was taken by Rosetta’s OSIRIS narrow-angle camera and downloaded 6 August. The image clearly shows a range of features, including boulders, craters and steep cliffs.
Copyright ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

The image was taken from a distance of 130 km and the image resolution is 2.4 metres per pixel.

This cluster of boulders reminded scientists of the famous pyramids at Giza near Cairo in Egypt, and thus it has been named Cheops for the largest of those pyramids, the Great Pyramid, which was built as a tomb for the pharaoh Cheops (also known as Kheops or Khufu) around 2550 BC.)

The image features a large boulder casting a long shadow on the surface of the comet. The boulder has a maximum dimension of about 45 metres and is the largest structure within a group of boulders located on the lower side of the comet’s larger lobe.

Credits: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

This image of the surface of Comet 67P/Churyumov-Gerasimenko was taken by Rosetta’s OSIRIS narrow-angle camera on 19 September 2014, from a distance of 28.5 km.
Using the CIVA camera on Rosetta’s Philae lander, the spacecraft have snapped a ‘selfie’ at comet 67P/Churyumov–Gerasimenko from a distance of about 16 km from the surface of the comet. The image was taken on 7 October and captures the side of the Rosetta spacecraft and one of Rosetta’s 14 m-long solar wings, with the comet in the background.

Copyright ESA/Rosetta/Philae/CIVA

Two images with different exposure times were combined to bring out the faint details in this very high contrast situation. The comet's active ‘neck’ region is clearly visible, with streams of dust and gas extending away from the surface.

The European Space Agency’s Rosetta mission will deploy its lander, Philae, to the surface of Comet 67P/Churyumov–Gerasimenko on 12 November.

Philae’s landing site, currently known as Site J, is located on the smaller of the comet’s two ‘lobes’, with a backup site on the larger lobe. The sites were selected just six weeks after Rosetta arrived at the comet on 6 August, following its 10-year journey through the Solar System

In that time, the Rosetta mission has been conducting an unprecedented scientific analysis of the comet, a remnant of the Solar System’s 4.6 billion-year history. The latest results from Rosetta will be presented on the occasion of the landing, during dedicated press briefings.

The main focus to date has been to survey 67P/Churyumov–Gerasimenko in order to prepare for the first ever attempt to soft-land on a comet.

Philae’s descent and science on the surface

Site J was chosen unanimously over four other candidate sites as the primary landing site because the majority of terrain within a square kilometre area has slopes of less than 30º relative to the local vertical and because there are relatively few large boulders. The area also receives sufficient daily illumination to recharge Philae and continue surface science operations beyond the initial 64-hour battery-powered phase. 

Site J


Over the last two weeks, the flight dynamics and operations teams at ESA have been making a detailed analysis of flight trajectories and timings for Rosetta to deliver the lander at the earliest possible opportunity.

Two robust landing scenarios have been identified, one for the primary site and one for the backup. Both anticipate separation and landing on 12 November.

For the primary landing scenario, targeting Site J, Rosetta will release Philae at 08:35 GMT/09:35 CET at a distance of 22.5 km from the centre of the comet, landing about seven hours later. The one-way signal travel time between Rosetta and Earth on 12 November is 28 minutes 20 seconds, meaning that confirmation of the landing will arrive at Earth ground stations at around 16:00 GMT/17:00 CET.

If a decision is made to use the backup Site C, separation will occur at 13:04 GMT/14:04 CET, 12.5 km from the centre of the comet. Landing will occur about four hours later, with confirmation on Earth at around 17:30 GMT/18:30 CET. The timings are subject to uncertainties of several minutes.

Philae’s primary landing site in context


Final confirmation of the primary landing site and its landing scenario will be made on 14 October after a formal Lander Operations Readiness Review, which will include the results of additional high-resolution analysis of the landing sites conducted in the meantime. Should the backup site be chosen at this stage, landing can still occur on 12 November.

A competition for the public to name the primary landing site will also be announced during the week of 14 October.

The Rosetta orbiter will continue to study the comet and its environment using its 11 science instruments as they orbit the Sun together. The comet is on an elliptical 6.5-year orbit that takes it from beyond Jupiter at its furthest point, to between the orbits of Mars and Earth at its closest to the Sun. Rosetta will accompany the comet for more than a year as they swing around the Sun and back to the outer Solar System again.

The analyses made by the Rosetta orbiter will be complemented by the in situ measurements performed by Philae’s 10 instruments.

Saturday, October 11, 2014

Coffee: If You're Not Shaking, You Need Another Cup

A team of researchers, including one from The University of Western Australia, has found there may be some truth in the slogan: "Coffee: If you're not shaking, you need another cup." They've identified the genes that determine just how much satisfaction you can get from caffeine.



The results could also help to explain why coffee, which is a major dietary source of caffeine and among the most widely consumed beverages in the world, is implicated in a range of health conditions.

Six new regions of DNA (loci) associated with coffee drinking behaviour are reported in the study published in Molecular Psychiatry.

The findings support the role of caffeine in promoting regular coffee consumption and may point to the molecular mechanisms that underlie why caffeine has different effects on different people.

The researchers included Dr Jennie Hui, the Director of the Busselton Health Study Laboratory and Adjunct Senior Research Fellow in UWA's School of Population Health.

The study was led by Marilyn Cornelis, a Postdoctoral Fellow at Harvard University, and colleagues who conducted a genome-wide association study of coffee consumption for 120,000 people of European and African-American ancestry.

"The findings highlight the properties of caffeine that give some of us the genetic propensity to consume coffee," Dr Hui said.

"Some of the gene regions determine the amount of coffee that makes individuals feel they are satisfied psychologically and others physiologically. What this tells us is that there may be molecular mechanism at work behind the different health and pharmacological effects of coffee and its constituents."

The authors of the study identified two loci, near genes BDNF and SLC6A4, that potentially reduce the level of satisfaction that we get from caffeine which may in turn lead to increased consumption.

Other regions near the genes POR and ABCG2 are involved in promoting the metabolism of caffeine.

The authors also identified loci in GCKR and near MLXIPL, genes involved in metabolism but not previously linked to either metabolism or a behavioural trait, such as coffee drinking.

The authors suggest that variations in GCKR may impact the glucose-sensing process of the brain, which may in turn influence responses to caffeine or some other component of coffee.

However, further studies are required to determine the effects of these two loci on coffee drinking behaviour.

The Busselton Health Study (BHS) is one of the world's longest running epidemiological research programs. Since 1966, it has contributed to an understanding of many common diseases and health conditions. The unique BHS database is compiled and managed by UWA's School of Population Health.



Contacts and sources:
Dr Jennie Hui (UWA School of Population Health and School of Pathology and Laboratory Medicine)
Adjunct Professor John Beilby (UWA School of Pathology and Laboratory Medicine

It Eats Like "100 Billion Billion Hot Dogs A Minute"

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 100 billion billion hot dogs every minute.

The discovery was published October 9th in the journal Nature.

A rendering of what P13 would look like close up.
Credit: Image created by Tom Russell (ICRAR) using software created by Rob Hynes (Louisiana State University).

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 realised 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.

Primary Image: A combined optical/X-ray image of NGC 7793


Credit: X-ray (NASA/CXC/Univ of Strasbourg/M. Pakull et al); Optical (ESO/VLT/Univ of Strasbourg/M. Pakull et al); H-alpha (NOAO/AURA/NSF/CTIO 1.5m)

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 compared P13 to small Japanese eating champion Takeru Kobayashi.

“As hotdog-eating legend Takeru Kobayashi famously showed us, size does not always matter in the world of competitive eating and even small black holes can sometimes eat gas at an exceptional rate,” he said.

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.

ICRAR is a joint venture between Curtin University and The University of Western Australia with support and funding from the State Government of Western Australia.

The study was led by Dr Christian Motch from the University of Strasbourg.


 Contacts and sources:
Dr Roberto Soria
ICRAR – Curtin

Carole Cowling
Curtin University

Citation: ‘A mass of less than 15 solar masses for the black hole in an ultraluminous X-ray source’ was published in Nature on 09 October 2014. C. Motch, M. W. Pakull, R. Soria, F. Grise, G. Pietrzynski. http://www.nature.com/nature/journal/v514/n7521/full/nature13730.html​

How Much Does Dark Matter in the Milky Way Weigh?

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 (800 billion 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 trillion 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.

This animation shows a supercomputer simulation of a galaxy like the Milky Way and its invisible dark matter halo. We zoom in to the galaxy and can see knots of dark matter where we would expect to see many satellite galaxies, but they don’t exist in the real Universe. That’s the missing satellite problem.

Credit: Prof Chris Power and Dr Rick Newton, ICRAR. Music by Reuben Christman (www.reubenchristman.com).

"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.

Artist’s impression of the Milky Way and its dark matter halo (shown in blue, but in reality invisible).
Credit: ESO/L. Calçada

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."

This artist’s impression shows the Milky Way galaxy. The blue halo of material surrounding the galaxy indicates the expected distribution of the mysterious dark matter, which was first introduced by astronomers to explain the rotation properties of the galaxy and is now also an essential ingredient in current theories of the formation and evolution of galaxies. New measurements show that the amount of dark matter in a large region around the Sun is far smaller than predicted and have indicated that there is no significant dark matter at all in our neighbourhood.
Credit:  ESO/L. Calçada

University of Sydney astrophysicist Professor Geraint Lewis, who was also involved in the research, said the missing satellite problem had been "a thorn in the cosmological side for almost 15 years."

"Dr Kafle's work has shown that it might not be as bad as everyone thought, although there are still problems to overcome," he said.

The study also presented a holistic model of the Milky Way, which allowed the scientists to measure several interesting things such as the speed required to leave the galaxy.

"Be prepared to hit 550 kilometres per second if you want to escape the gravitational clutches of our galaxy," Dr Kafle said.

"A rocket launched from Earth needs just 11 kilometres per second to leave its surface, which is already about 300 times faster than the maximum Australian speed limit in a car!"


Contacts and sources:
Dr Prajwal Kafle
ICRAR - UWA


‘On the Shoulders of Giants: Properties of the Stellar Halo and the Milky Way Mass Distribution' P. R. Kafle, S. Sharma, G. F. Lewis, and J. Bland-Hawthorn. Published in the Astrophysical Journal October 10th, 2014. Available at: http://iopscience.iop.org/0004-637X/794/1/59/

Pre-print paper available at: http://arxiv.org/abs/1408.1787

Thursday, October 9, 2014

Toshiba Unveils Android For Home And Office That Speaks And Signs

Toshiba Corporation revealed Tuesday that it had built a lifelike communication android that is being showcased at CEATEC JAPAN 2014 from October 7 to 11.

The communication android can move its arms and hands effortlessly and perform Japanese sign language for visitors.Toshiba Corp. believes its humanoid communication robot will not only work at front-desk reception at offices but also assist with nursing care.





The lifelike robot, which has smooth silicone-based skin, was jointly created by aLab Inc., Osaka University, Shibaura Institute of Technology and Shonan Institute of Technology.

The Aiko Chihira android is equipped with 43 servomotors that move her arms and hands. While it is common to see androids and robots that can interact and converse, one that has also mastered sign language is unusual.

Toshiba anticipates having enhanced Aiko Chihira’s technology so much by 2020 that it will be able to serve as an actual guide for foreign visitors to the Tokyo Olympic Games.

More from Japan Times

40,000 Year Old Painting On Indonesian Island Stuns Scientists, Rivals Oldest European Ice Age Art (Video)

Cave paintings from the Indonesian island of Sulawesi are at least 40 thousand years old, according to a study published this week in the scientific journal Nature.

This is compatible in age with the oldest known rock art from Europe, long seen as the birthplace of ‘Ice Age’ cave painting and home to the most sophisticated artworks in early human cultural history.

Cave paintings from the Indonesian island of Sulawesi

These new findings challenge long-cherished views about the origins of cave art, one of the most fundamental developments in our evolutionary past, according to Maxime Aubert from Griffith University, the dating expert who co-led the study.



“It is often assumed that Europe was the centre of the earliest explosion in human creativity, especially cave art, about 40 thousand years ago’, said Aubert, ‘but our rock art dates from Sulawesi show that at around the same time on the other side of the world people were making pictures of animals as remarkable as those in the Ice Age caves of France and Spain.”

The prehistoric images are from limestone caves near Maros in southern Sulawesi, a large island east of Borneo. They consist of stencilled outlines of human hands – made by blowing or spraying paint around hands pressed against rock surfaces – and paintings of primitive fruit-eating pigs called babirusas (‘pig-deer’).

These ancient images were first reported more than half a century ago, but there had been no prior attempts to date them.

Scientists determined the age of the paintings by measuring the ratio of uranium and thorium isotopes in small stalactite-like growths, called ‘cave popcorn’, which had formed over the art.

Cave paintings from the Indonesian island of Sulawesi

Using this high-precision method, known as U-series dating, samples from 14 paintings at seven caves were shown to range in age from 39.9 to 17.4 thousand years ago. As the cave popcorn grew on top of the paintings the U-series dates only provide minimum ages for the art, which could be far older.

The most ancient Sulawesi motif dated by the team, a hand stencil made at least ~40 thousand years ago, is now the oldest evidence ever discovered of this widespread form of rock art. A large painting of a female babirusa also yielded a minimum age of 35.4 thousand years, making it one of the earliest known figurative depictions in the world, if not the earliest.

This suggests that the creative brilliance required to produce the beautiful and stunningly life-like portrayals of animals seen in Palaeolithic Europe, such as those from the famous sites of Chauvet and Lascaux, could have particularly deep roots within the human lineage.

Panel of the Lions from  the Chauvet Cave

“In fact, cave painting and related forms of artistic expression were most likely part of the cultural traditions of the first modern humans to spread out of Africa and into Asia and Australia, long before they reached Europe,’’ said co-author Adam Brumm, also of Griffith University.

There are more than 90 cave art sites in the Maros area, according to Muhammad Ramli and Budianto Hakim, Indonesian co-leaders of the study, and hundreds of individual paintings and stencils, many of which are likely to be tens of thousands of years old.

The local cultural heritage management authority is now implementing a new policy to protect these rock art localities, some of which are already inscribed on the tentative list of World Heritage sites.


Contacts and sources:
Griffith University

Friday, October 3, 2014

City Of Origin Of HIV Virus And AIDS Found, Disease Sprang From Perfect Storm in 1920s


HIV pandemic's origins located. Pandemic spread almost certainly began in Democratic Republic of the Congo

The HIV pandemic with us today is almost certain to have begun its global spread from Kinshasa, the capital of the Democratic Republic of the Congo (DRC), according to a new study.

An international team, led by Oxford University and University of Leuven scientists, has reconstructed the genetic history of the HIV-1 group M pandemic, the event that saw HIV spread across the African continent and around the world, and concluded that it originated in Kinshasa. The team's analysis suggests that the common ancestor of group M is highly likely to have emerged in Kinshasa around 1920 (with 95% of estimated dates between 1909 and 1930).


Credit: Häggström, Mikael. "Medical gallery of Mikael Häggström 2014". Wikiversity Journal of Medicine 1 (2). DOI:10.15347/wjm/2014.008.

HIV is known to have been transmitted from primates and apes to humans at least 13 times but only one of these transmission events has led to a human pandemic. It was only with the event that led to HIV-1 group M that a pandemic occurred, resulting in almost 75 million infections to date. The team's analysis suggests that, between the 1920s and 1950s, a 'perfect storm' of factors, including urban growth, strong railway links during Belgian colonial rule, and changes to the sex trade, combined to see HIV emerge from Kinshasa and spread across the globe.

A report of the research is published in this week's Science.

'Until now most studies have taken a piecemeal approach to HIV's genetic history, looking at particular HIV genomes in particular locations,' said Professor Oliver Pybus of Oxford University's Department of Zoology, a senior author of the paper. 

'For the first time we have analysed all the available evidence using the latest phylogeographic techniques, which enable us to statistically estimate where a virus comes from. This means we can say with a high degree of certainty where and when the HIV pandemic originated. It seems a combination of factors in Kinshasa in the early 20th Century created a 'perfect storm' for the emergence of HIV, leading to a generalised epidemic with unstoppable momentum that unrolled across sub-Saharan Africa.'

'Our study required the development of a statistical framework for reconstructing the spread of viruses through space and time from their genome sequences,' said Professor Philippe Lemey of the University of Leuven's Rega Institute, another senior author of the paper. 'Once the pandemic's spatiotemporal origins were clear they could be compared with historical data and it became evident that the early spread of HIV-1 from Kinshasa to other population centres followed predictable patterns.'


Credit: CDC/ C. Goldsmith, P. Feorino, E. L. Palmer, W. R. McManus - This media comes from the Centers for Disease Control and Prevention's Public Health Image Library (PHIL),

One of the factors the team's analysis suggests was key to the HIV pandemic's origins was the DRC's transport links, in particular its railways, that made Kinshasa one of the best connected of all central African cities.

'Data from colonial archives tells us that by the end of 1940s over one million people were travelling through Kinshasa on the railways each year,' said Dr Nuno Faria of Oxford University's Department of Zoology, first author of the paper. 'Our genetic data tells us that HIV very quickly spread across the Democratic Republic of the Congo (a country the size of Western Europe), travelling with people along railways and waterways to reach Mbuji-Mayi and Lubumbashi in the extreme South and Kisangani in the far North by the end of the 1930s and early 1950s. This helped establishing early secondary foci of HIV-1 transmission in regions that were well connected to southern and eastern African countries. We think it is likely that the social changes around the independence in 1960 saw the virus 'break out' from small groups of infected people to infect the wider population and eventually the world.'

It had been suggested that demographic growth or genetic differences between HIV-1 group M and other strains might be major factors in the establishment of the HIV pandemic. However the team's evidence suggests that, alongside transport, social changes such as the changing behaviour of sex workers, and public health initiatives against other diseases that led to the unsafe use of needles may have contributed to turning HIV into a full-blown epidemic – supporting ideas originally put forward by study co-author Jacques Pepin from the Université de Sherbrooke, Canada.

Professor Oliver Pybus said: 'Our research suggests that following the original animal to human transmission of the virus (probably through the hunting or handling of bush meat) there was only a small 'window' during the Belgian colonial era for this particular strain of HIV to emerge and spread into a pandemic. By the 1960s transport systems, such as the railways, that enabled the virus to spread vast distances were less active, but by that time the seeds of the pandemic were already sown across Africa and beyond.'

The team says that more research is needed to understand the role different social factors may have played in the origins of the HIV pandemic; in particular research on archival specimens to study the origins and evolution of HIV, and research into the relationship between the spread of Hepatitis C and the use of unsafe needles as part of public health initiatives may give further insights into the conditions that helped HIV to spread so widely.


Contacts and sources:
Stephen Rouse
University of Oxford

Never Seen Before Maps Of The Ocean Floor, New Window On Tectonics Of The Deep Oceans


Mysteries of the deep come alive as satellite data bring thousands of uncharted sea mountains and new clues about deep ocean structures into focus.

A new seafloor map reveals new details on earthquakes (red dots), seafloor spreading ridges, and faults.




Accessing two previously untapped streams of satellite data, scientists at Scripps Institution of Oceanography at UC San Diego and their colleagues have created a new map of the world’s seafloor, creating a much more vivid picture of the structures that make up the deepest, least-explored parts of the ocean.
Thousands of previously uncharted mountains rising from the seafloor and new clues about the formation of the continents have emerged through the new map, which is twice as accurate as the previous version produced nearly 20 years ago.

Developed using a scientific model that captures gravity measurements of the ocean seafloor, the new map extracts data from the European Space Agency’s (ESA) CryoSat-2 satellite, which primarily captures polar ice data but also operates continuously over the oceans, and Jason-1, NASA’s satellite that was redirected to map the gravity field during the last year of its 12-year mission.

Marine gravity model of the North Atlantic (10 mGal contours). Red dots show locations of earthquakes with magnitude > 5.5 and they highlight the present-day location of the seafloor spreading ridges and transform faults. This gravity information shows the details of the plate tectonic history of the rifting of these continents including the subtle signatures of fracture zones that are currently buried by sediment.
Combined with existing data and drastically improved remote sensing instruments, the new map, described in the journal Science, has revealed details of thousands of undersea mountains, or seamounts, extending a kilometer or more from the ocean bottom. The new map also gives geophysicists new tools to investigate ocean spreading centers and little-studied remote ocean basins.

Vertical gravity gradient (VGG) model of the southern mid-Atlantic Ridge. Earthquakes with magnitude > 5.5 are shown as green dots and highlight the current location of the spreading ridges and transform faults. The large fracture zone signatures record the rifting and spreading between South America and Africa.

“The kinds of things you can see very clearly now are abyssal hills, which are the most common land form on the planet,” said David Sandwell, lead scientist of the paper and a geophysics professor in the Cecil H. and Ida M. Green Institute of Geophysics and Planetary Physics (IGPP) at Scripps.

Draining the Ocean Basins with CryoSat-2 from Marine Gravity

Vimeo.

The authors of the study say the map provides a new window into the tectonics of the deep oceans. Previously unseen features in the map include newly exposed continental connections across South America and Africa, and new evidence for seafloor spreading ridges at the Gulf of Mexico that were active 150 million years ago and are now buried by mile-thick layers of sediment.

Vertical gravity gradient (VGG) model of the southern mid-Atlantic Ridge. Earthquakes with magnitude > 5.5 are shown as green dots and highlight the current location of the spreading ridges and transform faults. The large fracture zone signatures record the rifting and spreading between South America and Africa.


“One of the most important uses of this new marine gravity field will be to improve the estimates of seafloor depth in the 80 percent of the oceans that remains uncharted or is buried beneath thick sediment,” the authors say in the report.

These cloud-based tools are hosted on the GPlates Web Portal and require a WebGL-enabled browser.














“Although CryoSat-2’s primary mission is in the cryosphere, we knew as soon as we selected its orbit that it would be invaluable for marine geodesy, and this work proves the point,” said Richard Francis, a coauthor of the paper and project manager for the development of CryoSat-2 at the European Space Agency, and honorary professor in the Department of Earth Sciences at University College London.

Marine gravity model of the Central Indian Ocean (10 mGal contours). Red dots show locations of earthquakes with magnitude > 5.5 and they highlight the present-day location of the seafloor spreading ridges and transform faults. The image is centered at the Indian Ocean Triple Junction where three major tectonic plates meet (African plate – left; Indo-Australian plate – right; Antarctic plate bottom. This region of the Indian Ocean is very poorly charted and includes the search area for the Malaysian flight MH370 that was lost March 8, 2014.


The new map also provides the foundation for the upcoming new version of Google’s ocean maps to fill large voids between shipboard depth profiles.

“The team has developed and proved a powerful new tool for high-resolution exploration of regional seafloor structure and geophysical processes,” says Don Rice, program director in the National Science Foundation’s (NSF) Division of Ocean Sciences. “This capability will allow us to revisit unsolved questions and to pinpoint where to focus future exploratory work.”

Vertical gravity gradient (VGG) model of the Indian Ocean Triple Junction. The image is centered at the Indian Ocean Triple Junction where three major tectonic plates meet (African plate – left; Indo-Australian plate – right; Antarctic plate bottom.


“The use of satellite altimeter data and Sandwell’s improved data processing technique provides improved estimates of marine gravity and bathymetry world-wide, including in remote areas,” said Joan Cleveland, Office of Naval Research (ONR) deputy director, Ocean Sensing and Systems Division. “Accurate bathymetry and identifying the location of seamounts are important to safe navigation for the U.S. Navy.”

In addition to Sandwell and Francis, coauthors of the paper include R. Dietmar Muller of the University of Sydney, Walter Smith of the NOAA Laboratory for Satellite Altimetry, and Emmanuel Garcia of Scripps.

The study was supported by NSF, ONR, the National Geospatial-Intelligence Agency, and ConocoPhillips.


Contacts and sources:
Scripps Institution of Oceanography

Wednesday, October 1, 2014

Possible Origin Of “Ocean of Storms” On Earth’s Moon

Using data from NASA’s Gravity Recovery and Interior Laboratory (GRAIL), mission scientists have solved a lunar mystery almost as old as the moon itself.

Early theories suggested the craggy outline of a region of the moon’s surface known as Oceanus Procellarum, or the Ocean of Storms, was caused by an asteroid impact. If this theory had been correct, the basin it formed would be the largest asteroid impact basin on the moon. 

However, mission scientists studying GRAIL data believe they have found evidence the craggy outline of this rectangular region -- roughly 1,600 miles (2,600 kilometers) across -- is actually the result of the formation of ancient rift valleys.

Earth's moon as observed in visible light (left), topography (center, where red is high and blue is low), and the GRAIL gravity gradients (right). The Procellarum region is a broad region of low topography covered in dark mare basalt. The gravity gradients reveal a giant rectangular pattern of structures surrounding the region.
Earth's moon as observed in visible light (left), topography (center, where red is high and blue is low), and the GRAIL gravity gradients
Image Credit: NASA/GSFC/JPL/Colorado School of Mines/MIT

"The nearside of the moon has been studied for centuries, and yet continues to offer up surprises for scientists with the right tools," said Maria Zuber, principal investigator of NASA's GRAIL mission, from the Massachusetts Institute of Technology, Cambridge. "We interpret the gravity anomalies discovered by GRAIL as part of the lunar magma plumbing system -- the conduits that fed lava to the surface during ancient volcanic eruptions."

The surface of the moon’s nearside is dominated by a unique area called the Procellarum region, characterized by low elevations, unique composition, and numerous ancient volcanic plains.

The rifts are buried beneath dark volcanic plains on the nearside of the moon and have been detected only in the gravity data provided by GRAIL. The lava-flooded rift valleys are unlike anything found anywhere else on the moon and may at one time have resembled rift zones on Earth, Mars and Venus. The findings are published online in the journal Nature.

Another theory arising from recent data analysis suggests this region formed as a result of churning deep in the interior of the moon that led to a high concentration of heat-producing radioactive elements in the crust and mantle of this region. Scientists studied the gradients in gravity data from GRAIL, which revealed a rectangular shape in resulting gravitational anomalies.

"The rectangular pattern of gravity anomalies was completely unexpected," said Jeff Andrews-Hanna, a GRAIL co-investigator at the Colorado School of Mines in Golden, Colorado, and lead author of the paper. "Using the gradients in the gravity data to reveal the rectangular pattern of anomalies, we can now clearly and completely see structures that were only hinted at by surface observations."

The rectangular pattern, with its angular corners and straight sides, contradicts the theory that Procellarum is an ancient impact basin, since such an impact would create a circular basin. Instead, the new research suggests processes beneath the moon’s surface dominated the evolution of this region.

Over time, the region would cool and contract, pulling away from its surroundings and creating fractures similar to the cracks that form in mud as it dries out, but on a much larger scale.

The study also noted a surprising similarity between the rectangular pattern of structures on the moon, and those surrounding the south polar region of Saturn’s icy moon Enceladus. Both patterns appear to be related to volcanic and tectonic processes operating on their respective worlds.

"Our gravity data are opening up a new chapter of lunar history, during which the moon was a more dynamic place than suggested by the cratered landscape that is visible to the naked eye," said Andrews-Hanna. "More work is needed to understand the cause of this newfound pattern of gravity anomalies, and the implications for the history of the moon."

Launched as GRAIL A and GRAIL B in September 2011, the probes, renamed Ebb and Flow, operated in a nearly circular orbit near the poles of the moon at an altitude of about 34 miles (55 kilometers) until their mission ended in December 2012. The distance between the twin probes changed slightly as they flew over areas of greater and lesser gravity caused by visible features, such as mountains and craters, and by masses hidden beneath the lunar surface.

The twin spacecraft flew in a nearly circular orbit until the end of the mission on Dec. 17, 2012, when the probes intentionally were sent into the moon’s surface. NASA later named the impact site in honor of late astronaut Sally K. Ride, who was America's first woman in space and a member of the GRAIL mission team.

GRAIL’s prime and extended science missions generated the highest resolution gravity field map of any celestial body. The map will provide a better understanding of how Earth and other rocky planets in the solar system formed and evolved.

The GRAIL mission was managed by NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, for NASA's Science Mission Directorate in Washington. The mission was part of the Discovery Program managed at NASA's Marshall Space Flight Center in Huntsville, Alabama. GRAIL was built by Lockheed Martin Space Systems in Denver.

For more information about GRAIL, visit:
http://www.nasa.gov/grail



Contacts and sources:
Dwayne Brown
Headquarters, Washington

DC Agle
Jet Propulsion Laboratory, Pasadena, Calif.

Kathleen Morton
Colorado School of Mines, Golden

Monday, September 29, 2014

Supersonic, Bi-Directional Flying Wing Would Fly From New York To Tokyo In 4 Hours

Imagine flying from New York to Tokyo in only four hours aboard a fuel-efficient supersonic jet that looks like something right out of Star Wars. Such a plane could become reality in the next two to three decades, thanks to the efforts of a University of Miami aerospace engineering professor.

Ge-Cheng Zha’s supersonic, bi-directional flying wing will be able to whisk passengers from New York to Tokyo in four hours.

Credit: University of Miami

Ge-Cheng Zha, along with collaborators from Florida State University, is designing a supersonic, bi-directional flying wing (SBiDir-FW) capable of whisking passengers to destinations in significantly less time than it would take conventional aircraft—and without the sonic boom generated by aircraft breaking the sound barrier.

The project has just been awarded a $100,000 grant from NASA’s prestigious Innovative Advanced Concepts program, allowing Zha and colleagues to continue development of their high-tech, futuristic plane.

“I am glad that this novel concept is recognized by the technological authorities for its scientific merit,” said Zha, a professor in UM’s College of Engineering and principal investigator of the project. “This prize means that NASA rewards audacious thinking.”

NASA selected Zha’s design and other the projects based on their potential to transform future aerospace missions, enable new capabilities, or significantly alter and improve current approaches to launching, building, and operating aerospace systems.

“These selections represent the best and most creative new ideas for future technologies that have the potential to radically improve how NASA missions explore new frontiers,” said Michael Gazarik, director of NASA’s Space Technology Program. “Through the NASA Innovative Advanced Concepts program, NASA is taking the long-term view of technological investment and the advancement that is essential for accomplishing our missions. We are inventing the ways in which next-generation aircraft and spacecraft will change the world and inspiring Americans to take bold steps.”

With his supersonic bi-directional flying wing, Zha hopes to achieve zero sonic boom, low supersonic wave drag, and low fuel consumption for passenger travel.

“I am hoping to develop an environmentally friendly and economically viable airplane for supersonic civil transport in the next 20 to 30 years,” said Zha. “Imagine flying from New York to Tokyo in four hours instead of 15 hours.”

Conventional airplanes are composed of a tube-shaped fuselage with two wings inserted and are symmetric along the longitudinal axis. Such a fuselage is designed to hold passengers and cargo, with lift being generated by the wings. “Hence, a conventional airplane is not very efficient and generates a strong sonic boom,” says Zha.

The SBiDir-FW platform is symmetric along both the longitudinal and span axes. It is a flying wing that generates lift everywhere and is able to rotate 90 degrees during flight between supersonic and subsonic speeds, explains Zha.

“No matter how fast a supersonic plane can fly, it needs to take off and land at very low speed, which severely hurts the high-speed supersonic performance for a conventional airplane,” said Zha. “The SBiDir-FW removes this performance conflict by rotating the airplane to fly in two different directions at subsonic and supersonic. Such rotation enables the SBiDir-FW to achieve superior performance at both supersonic and subsonic speeds.”

Innovative Advanced Concepts awards enable scientists to explore basic feasibility and properties of a potential breakthrough concept. The projects were chosen through a peer-review process that evaluated their innovation and how technically viable they are. All are very early in development—20 years or longer from being used on a mission.

Louis Cattafesta, professor of aerospace engineering at Florida State University, and Farrukh Alvi, professor and director of the Florida Center for Advanced Aero-Propulsion at FSU, are also working on the SBiDir-FW.


Contacts and sources:
University of Miami

Saturday, August 30, 2014

Ebola Virus Mutating Quickly Says Scientists Genomic

More than 300 genetic mutations have been discovered in the Ebola virus according to genetic researchers.  

In response to an ongoing, unprecedented outbreak of Ebola virus disease (EVD) in West Africa, a team of researchers from the Broad Institute and Harvard University, in collaboration with the Sierra Leone Ministry of Health and Sanitation and researchers across institutions and continents, has rapidly sequenced and analyzed more than 99 Ebola virus genomes. Their findings could have important implications for rapid field diagnostic tests. The team reports its results online in the journal Science.

Ebola Virus Particles
Credit: Thomas W. Geisbert, Boston University School of Medicine - PLoS Pathogens

For the current study, researchers sequenced 99 Ebola virus genomes collected from 78 patients diagnosed with Ebola in Sierra Leone during the first 24 days of the outbreak (a portion of the patients contributed samples more than once, allowing researchers a clearer view into how the virus can change in a single individual over the course of infection). 

The team found more than 300 genetic changes that make the 2014 Ebola virus genomes distinct from the viral genomes tied to previous Ebola outbreaks. They also found sequence variations indicating that, from the samples sequenced, the EVD outbreak started from a single introduction into humans, subsequently spreading from person to person over many months.

The variations they identified were frequently in regions of the genome encoding proteins. Some of the genetic variation detected in these studies may affect the primers (starting points for DNA synthesis) used in PCR-based diagnostic tests, emphasizing the importance of genomic surveillance and the need for vigilance.
To accelerate response efforts, the research team released the full-length sequences on National Center for Biotechnology Information’s (NCBI’s) DNA sequence database in advance of publication, making these data available to the global scientific community.

“By making the data immediately available to the community, we hope to accelerate response efforts,” said co-senior author Pardis Sabeti, a senior associate member at the Broad Institute and an associate professor at Harvard University. “Upon releasing our first batch of Ebola sequences in June, some of the world’s leading epidemic specialists contacted us, and many of them are now also actively working on the data. We were honored and encouraged. A spirit of international and multidisciplinary collaboration is needed to quickly shed light on the ongoing outbreak.”

The 2014 Zaire ebolavirus (EBOV) outbreak is unprecedented both in its size and in its emergence in multiple populated areas. Previous outbreaks had been localized mostly to sparsely populated regions of Middle Africa, with the largest outbreak in 1976 reporting 318 cases. The 2014 outbreak has manifested in the more densely-populated West Africa, and since it was first reported in Guinea in March 2014, 2,240 cases have been reported with 1,229 deaths (as of August 19).

Augustine Goba, Director of the Lassa Laboratory at the Kenema Government Hospital and a co-first author of the paper, identified the first Ebola virus disease case in Sierra Leone using PCR-based diagnostics. "We established surveillance for Ebola well ahead of the disease’s spread into Sierra Leone and began retrospective screening for the disease on samples as far back as January of this year,” said Goba. “This was possible because of our long-standing work to diagnose and study another deadly disease, Lassa fever. We could thus identify cases and trace the Ebola virus spread as soon as it entered our country.”

The research team increased the amount of genomic data available on the Ebola virus by four fold and used the technique of “deep sequencing” on all available samples. Deep sequencing is sequencing done enough times to generate high confidence in the results. In this study, researchers sequenced at a depth of 2,000 times on average for each Ebola genome to get an extremely close-up view of the virus genomes from 78 patients. This high-resolution view allowed the team to detect multiple mutations that alter protein sequences -- potential targets for future diagnostics, vaccines, and therapies.

The Ebola strains responsible for the current outbreak likely have a common ancestor, dating back to the very first recorded outbreak in 1976. The researchers also traced the transmission path and evolutionary relationships of the samples, revealing that the lineage responsible for the current outbreak diverged from the Middle African version of the virus within the last ten years and spread from Guinea to Sierra Leone by 12 people who had attended the same funeral.

The team’s catalog of 395 mutations (over 340 that distinguish the current outbreak from previous ones, and over 50 within the West African outbreak) may serve as a starting point for other research groups. “We’ve uncovered more than 300 genetic clues about what sets this outbreak apart from previous outbreaks,” said Stephen Gire, a research scientist in the Sabeti lab at the Broad Institute and Harvard. “Although we don’t know whether these differences are related to the severity of the current outbreak, by sharing these data with the research community, we hope to speed up our understanding of this epidemic and support global efforts to contain it.”

“There is an extraordinary battle still ahead, and we have lost many friends and colleagues already like our good friend and colleague Dr. Humarr Khan, a co-senior author here,” said Sabeti. “By providing this data to the research community immediately and demonstrating that transparency and partnership is one way we hope to honor Humarr’s legacy. We are all in this fight together.”

This work was supported by Common Fund and National Institute of Allergy and Infectious Diseases in the National Institutes of Health, Department of Health and Human Services, as well as by the National Science Foundation, the European Union Seventh Framework Programme, the World Bank, and the Natural Environment Research Council.

Other researchers who contributed to this work include Augustine Goba, Kristian G. Andersen, Rachel S. G. Sealfon, Daniel J. Park, Lansana Kanneh, Simbirie Jalloh, Mambu Momoh, Mohamed Fullah, Gytis Dudas, Shirlee Wohl, Lina M. Moses, Nathan L. Yozwiak, Sarah Winnicki, Christian B. Matranga, Christine M. Malboeuf, James Qu, Adrianne D. Gladden, Stephen F. Schaffner, Xiao Yang, Pan-Pan Jiang, Mahan Nekoui, Andres Colubri, Moinya Ruth Coomber, Mbalu Fonnie, Alex Moigboi, Michael Gbakie, Fatima K. Kamara, Veronica Tucker, Edwin Konuwa, Sidiki Saffa, Josephine Sellu, Abdul Azziz Jalloh, Alice Kovoma, James Koninga, Ibrahim Mustapha, Kandeh Kargbo, Momoh Foday, Mohamed Yillah, Franklyn Kanneh, Willie Robert, James L. B. Massally, Sinéad B. Chapman, James Bochicchio, Cheryl Murphy, Chad Nusbaum, Sarah Young, Bruce W. Birren, Donald S.Grant, John S. Scheiffelin, Eric S. Lander, Christian Happi, Sahr M. Gevao, Andreas Gnirke, Andrew Rambaut, Robert F. Garry, and S. Humarr Khan.

About the Broad Institute of MIT and Harvard


The Eli and Edythe L. Broad Institute of MIT and Harvard was launched in 2004 to empower this generation of creative scientists to transform medicine. The Broad Institute seeks to describe all the molecular components of life and their connections; discover the molecular basis of major human diseases; develop effective new approaches to diagnostics and therapeutics; and disseminate discoveries, tools, methods, and data openly to the entire scientific community.

Founded by MIT, Harvard, and its affiliated hospitals, and the visionary Los Angeles philanthropists Eli and Edythe L. Broad, the Broad Institute includes faculty, professional staff, and students from throughout the MIT and Harvard biomedical research communities and beyond, with collaborations spanning over a hundred private and public institutions in more than 40 countries worldwide. 


Contacts and sources:

Citation: Gire, SK, Goba, A et al. Genomic surveillance elucidates Ebola virus origin and transmission during the 2014 outbreak. Science. DOI: 10.1126/science.1259657

Friday, August 29, 2014

300 Meter Fissure Erupts, Closes Iceland Airspace

Just after midnight on August 29,  a fissure eruption started in the Northern part of Holuhraun lava, between Dyngjujökull Glacier and the Askja caldera, North of Vatnajökull glacier. The fissure is 300 meters long and in direction Northeast and Southwest.
  
No volcanic ash has been detected with the radar system at the moment. The wind field conditions in the area are wind blowing toward NW at 12 m/s at 5 km altitude. Seismic eruption tremor is low indicating effusive eruption without significant explosive activity.

Scientists who have been at work close to the eruption monitor the event at a safe distance. The Coast Guard aircraft, TF-SIF is scheduled to take off at 9:30 this morning. The Icelandic Met Office has raised the aviation colorcode over the eruption site to red and the Icelandic Air Traffic Contol has closed down the airspace from the earth up to 18000 feet for instrumental flights (see picture below).
The National Crisis Coordination Center is active and the Commissioner of the Icelandic Police has raised the Civil Protection Phase to Emergency Phase in collaboration with the District Commissioner in Husavík..

About an hour later the  ÍSAVÍA No-fly zone for instrumental flight was reevaluated and can be seen on the map. It is smaller than before, Akureyri airport is no longer under restrictions and the height of the zone now only reaches 5000 feet.


Source: Civil Protection in Iceland

Wednesday, August 27, 2014

Best View Yet Of Merging Galaxies In Distant Universe

Using the NASA/ESA Hubble Space Telescope and many other telescopes on the ground and in space, an international team of astronomers has obtained the best view yet of a collision that took place between two galaxies when the Universe was only half its current age.
Credit: ESO

They enlisted the help of a galaxy-sized magnifying glass to reveal otherwise invisible detail. These new studies of the galaxy H-ATLAS J142935.3-002836 have shown that this complex and distant object looks like the well-known local galaxy collision, the Antennae Galaxies.

The famous fictional detective Sherlock Holmes used a magnifying lens to reveal barely visible but important evidence. Astronomers are now combining the power of many telescopes on Earth and in space [1] with a vastly larger form of lens to study a case of vigorous star formation in the early Universe.

This diagram shows how the effect of gravitational lensing around a normal galaxy focuses the light coming from a very distant star-forming galaxy merger to created a distorted, but brighter view. 
 Credit: ESA/ESO/M. Kornmesser

"While astronomers are often limited by the power of their telescopes, in some cases our ability to see detail is hugely boosted by natural lenses, created by the Universe," explains lead author Hugo Messias of the Universidad de Concepción (Chile) and the Centro de Astronomia e Astrofísica da Universidade de Lisboa (Portugal), "Einstein predicted in his theory of general relativity that, given enough mass, light does not travel in a straight line but will be bent in a similar way to light refracted by a normal lens."

These cosmic lenses are created by massive structures like galaxies and galaxy clusters, which deflect the light from objects behind them due to their strong gravity — an effect, called gravitational lensing. The magnifying properties of this effect allow astronomers to study objects that would not be visible otherwise and to directly compare local galaxies with much more remote ones, seen when the Universe was significantly younger.

This video takes the viewer deep into an apparently sparsely occupied region of the constellation of Virgo (The Virgin). Here at the centre, looking like many other faint spots, is a remarkable object, a gravitationally lensed view of a distant galaxy merger.

Credit: NASA/ESA/W. M. Keck Observatory/Digitized Sky Survey 2. Music: movetwo

But for these gravitational lenses to work, the lensing galaxy, and the one far behind it, need to be very precisely aligned.

"These chance alignments are quite rare and tend to be hard to identify," adds Messias, "but, recent studies have shown that by observing at far-infrared and millimetre wavelengths we can find these cases much more efficiently."

This artist's impression shows how the effect of gravitational lensing by an intervening galaxy magnifies, brightens and distorts the appearance of a remote merging galaxy far behind it.

The viewpoint of the observer moves sideways so that that the distant galaxy merger appears first to one side, where it is faint, and then appears right behind the foreground object and is dramatically magnified and its total apparent brightness increases.

Credit: ESA/Hubble & ESO/M. Kornmesser

H-ATLAS J142935.3-002836 (or just H1429-0028 for short) is one of these sources and was found in the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS). It is among the brightest gravitationally lensed objects in the far-infrared regime found so far, even though we are seeing it at a time when the Universe was just half its current age.

Probing this object was at the limit of what is possible, so the international team of astronomers started an extensive follow-up campaign using the NASA/ESA Hubble Space Telescope alongside other space telescopes and some of the most powerful telescopes on the ground — including the Atacama Large Millimeter/submillimeter Array (ALMA), the Keck Observatory, the Karl Jansky Very Large Array (JVLA), and others. The different telescopes provided different views, which could be combined to get the best insight yet into the nature of this unusual object.

The Hubble and Keck images revealed a detailed gravitationally-induced ring of light around the foreground galaxy. These high resolution images also showed that the lensing galaxy is an edge-on disc galaxy — similar to our galaxy, the Milky Way — which obscures parts of the background light due to the large dust clouds it contains.

"We need to observe with Hubble to find cases of gravitational lensing and to highlight in high resolution the clues left by these huge cosmic lenses", adds Rob Ivison, co-author and ESO's Director for Science

But, it is not possible to see past the large dust clouds of the foreground galaxy with Hubble. The obscuration was overcome by ALMA and the JVLA, since these two facilities observe the sky at longer wavelengths, which are unaffected by dust. Using the combined data the team discovered that the background system was actually an ongoing collision between two galaxies.

Further characterisation of the object was undertaken by ALMA which traced carbon monoxide, allowing for detailed studies of star formation mechanisms in galaxies and for the motion of the material in the galaxy to be measured. This confirmed that the lensed object is indeed an ongoing galactic collision forming hundreds of new stars each year, and that one of the colliding galaxies still shows signs of rotation; an indication that it was a disc galaxy just before this encounter.

The system of these two colliding galaxies resembles the Antennae Galaxies an object much closer to us than H1429-0028 and which Hubble has imaged several times before in stunning detail. This is a spectacular collision between two galaxies, which are believed to have had a disc structure in the past. While the Antennae system is forming stars with a total rate of only a few tens of times the mass of our Sun each year, H1429-0028 each year turns more than 400 times the mass of the Sun of gas into new stars each year.

Ivison concludes: "With the combined power of Hubble and these other telescopes we have been able to locate this very fortunate alignment, take advantage of the foreground galaxy's lensing effects and characterise the properties of this distant merger and the extreme starburst within it. It is very much a testament to the power of telescope teamwork."
Notes

[1] The telescopes and surveys that were employed were: the NASA/ESA Hubble Space Telescope, ALMA, APEX, VISTA, the Gemini South telescope, the Keck-II telescope, the NASA Spitzer Space Telescope, the Jansky Very Large Array, CARMA, IRAM, and SDSS and WISE.



Contacts and sources:
Georgia Bladon
ESA/Hubble Information Centre