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Upconversion (UC) nanoparticles (UCNPs) have evoked considerable attention in many fields owing to their fascinating features. However, rigorous synthesis conditions and expensive raw materials often limit their further applications. Here, a novel hexagonal phase NaBiF UC matrix through a very facile method (one min only at room temperature) is synthesized. The nanoparticles show good monodispersity with uniform size. Under the 980 nm irradiation, Yb3+/Ln3+ (Ln = Er, Ho, Tm) codoped NaBiF nanoparticles show excellent UC luminescence (UCL). This super facile synthesis strategy and excellent matrix materials enable to achieve UCL in such low temperature, opening a new gateway for the UCNPs applied to a variety of areas in the future.


News Article | April 17, 2017
Site: www.newscientist.com

Unpicking the secrets of the brain’s reward system has earned three neuroscientists a reward of their own. Wolfram Schultz, Peter Dayan, and Ray Dolan have today been awarded the €1 million Brain Prize by Denmark’s Lundbeck Foundation. The prize recognises researchers who have made vital contributions to understanding how our brains work. Together, their research has revealed how reward systems in the brain that involve the signalling chemical dopamine influence our behaviour and survival, playing important roles in decision-making, gambling, drug addiction, psychopathic tendencies, and schizophrenia. “This is the biological process that makes us want to buy a bigger car or house, or be promoted at work,” says Wolfram Schultz, at the University of Cambridge. Schultz discovered through experiments on monkeys 30 years ago that when the animals receive a reward, specialised brain cells become more active and make dopamine. Subsequently, he showed that this could be triggered through learned cues, even without a reward. Peter Dayan, at University College London, took Schultz’s work further by showing how we constantly update our goals through a dopamine-driven phenomenon called “reward prediction error”. Dayan showed how our future behaviour is dictated by daily feedback on whether anticipated rewards and pleasures either fail to materialise or are more generous than anticipated. “Nature has endowed us with a fantastic system for optimising our behaviour,” said Dayan at a press briefing in London. Dayan is now working on applying the logic of decision making seen in the dopamine system to artificial intelligence algorithms. “That’s how you get computers to make predictions,” he said. Ray Dolan, of the Max Planck UCL Centre for Computational Psychiatry and Ageing in Berlin, Germany, has further explored the influence of dopamine on decision making. As we age, people lose around 10 per cent of their dopamine-producing neurons, which can deplete a person’s ability to predict future rewards accurately. Dolan has shown that this ability can be restored by giving older people extra supplies of dopamine. After the advances they have made in understanding rewards, the researchers are now exploring how the brain responds to punishment. Dayan says the smart money is on another brain signalling chemical, serotonin. “That may be involved in punishment, but it’s fairly speculative at the moment.”


News Article | May 1, 2017
Site: www.eurekalert.org

The brain responds less to money gained from immoral actions than money earned decently, reveals a new UCL-led study. The research, published in Nature Neuroscience and funded by Wellcome, helps explain why most people are reluctant to seek illicit gains by identifying a neural process that dampens the appeal of profiting at other people's expense. "When we make decisions, a network of brain regions calculates how valuable our options are," explained lead author Dr Molly Crockett of the University of Oxford, who carried out the research while based at the UCL Wellcome Centre for Neuroimaging. "Ill-gotten gains evoke weaker responses in this network, which may explain why most people would rather not profit from harming others. Our results suggest the money just isn't as appealing." The research team scanned volunteers' brains as they decided whether to anonymously inflict pain on themselves or strangers in exchange for money. The study builds on previous research by the same team that showed people dislike harming others more than harming themselves. This behaviour was seen again in this study, with most people more willing to harm themselves than others for profit. The study involved 28 pairs of participants who were anonymously paired and randomly assigned to be either the 'decider' or the 'receiver'. Deciders picked between different amounts of money for different numbers of electric shocks. Half the decisions related to shocks for themselves and half to shocks for the receiver, but in all cases the deciders would get the money. The shocks were matched to each recipient's pain threshold to be mildly painful but tolerable. The deciders were in an fMRI brain scanner. As they made their decisions, a brain network including the striatum was activated, as it has been shown in previous studies to be key to value computation. As they decided between more profitable options or those with fewer shocks, this brain network signalled how beneficial each option was. The network responded less to money gained from shocking others, compared with money gained from shocking oneself - but only in those people who behaved morally. Meanwhile, the lateral prefrontal cortex (LPFC), a brain region involved in making moral judgments, was most active in trials where inflicting pain yielded minimal profit. In a follow-up study, participants made moral judgements about decisions to harm others for profit, and considered those same trials to be the most blameworthy. Taken together, the findings suggest the LPFC was assessing blame. When people refused to profit from harming others, this region was communicating with the striatum, suggesting that neural representations of moral rules might disrupt the value of ill-gotten gains encoded in the striatum. "Our findings suggest the brain internalizes the moral judgments of others, simulating how much others might blame us for potential wrongdoing, even when we know our actions are anonymous," Dr Crockett said. Senior author Professor Ray Dolan (UCL Max Planck Centre for Computational Psychiatry and Ageing Research) said: "What we have shown here is how values that guide our decisions respond flexibly to moral consequences. An important goal for future research is understanding when and how this circuitry is disturbed in contexts such as antisocial behaviour."


News Article | April 20, 2017
Site: www.scientificcomputing.com

Six High Performance Computing (HPC) centres that will give academics and industry access to powerful computers to support research in engineering and the physical sciences, will be officially launched on Thursday 30 March at the Thinktank science museum in Birmingham. Funded by £20 million from the Engineering and Physical Sciences Research Council (EPSRC) the centres are located around the UK, at the universities of Cambridge, Edinburgh, Exeter, and Oxford, Loughborough University, and UCL. Professor Philip Nelson, EPSRC's Chief Executive, said: "These centres will enable new discoveries, drive innovation and allow new insights into today's scientific challenges. They are important because they address an existing gulf in capability between local university systems and the UK National Supercomputing Service ARCHER. Many universities are involved in the six new centres, and these will give more researchers easy access to High Performance Computing." The centres will be used by a diverse range of the research community and will, for example, be used to predict how a jet engine will perform; explore new materials for energy generation and storage; and develop driverless cars. Some of the centres will be available free of charge to any EPSRC-supported researcher, and some will give access to UK industry. The new centres provide a diversity of computing architectures, which are driven by science needs and are not met by the national facilities or universities. This is because the National HPC Service must meet the needs of the whole UK community and so cannot specialise in specific novel architectures or novel requirements. The different types of computing requirements provided by this Tier-2 group include high-throughput and GPU computing; for example, the JADE system at the University of Oxford will be the largest GPU facility in the UK. The GW4 centre will be a world-leading ARM-based testbed, where scientists will be able to choose from a wide range of emerging architectures to run their applications.


News Article | April 20, 2017
Site: www.scientificcomputing.com

Six High Performance Computing (HPC) centres that will give academics and industry access to powerful computers to support research in engineering and the physical sciences, will be officially launched on Thursday 30 March at the Thinktank science museum in Birmingham. Funded by £20 million from the Engineering and Physical Sciences Research Council (EPSRC) the centres are located around the UK, at the universities of Cambridge, Edinburgh, Exeter, and Oxford, Loughborough University, and UCL. Professor Philip Nelson, EPSRC's Chief Executive, said: "These centres will enable new discoveries, drive innovation and allow new insights into today's scientific challenges. They are important because they address an existing gulf in capability between local university systems and the UK National Supercomputing Service ARCHER. Many universities are involved in the six new centres, and these will give more researchers easy access to High Performance Computing." The centres will be used by a diverse range of the research community and will, for example, be used to predict how a jet engine will perform; explore new materials for energy generation and storage; and develop driverless cars. Some of the centres will be available free of charge to any EPSRC-supported researcher, and some will give access to UK industry. The new centres provide a diversity of computing architectures, which are driven by science needs and are not met by the national facilities or universities. This is because the National HPC Service must meet the needs of the whole UK community and so cannot specialise in specific novel architectures or novel requirements. The different types of computing requirements provided by this Tier-2 group include high-throughput and GPU computing; for example, the JADE system at the University of Oxford will be the largest GPU facility in the UK. The GW4 centre will be a world-leading ARM-based testbed, where scientists will be able to choose from a wide range of emerging architectures to run their applications.


News Article | April 21, 2017
Site: marketersmedia.com

A new Festival to be held in Hay-on-Wye for Book Lovers and Lovers of Art, Music and Ideas looking for the latest information on Love and Relationships is being launched this year and interested parties can now register to attend The Greatest Adventure – Love in the time of Tinder. It’s a new May Day weekend Festival for Hay-on-Wye, scheduled for 29 and 30 April 2017, the first bank-holiday weekend in May in the UK. Hideaways In Hay, based in Hay-on-Wye on the border of England and Wales, whose two holiday cottages have been voted consistently the Nº 1 Romantic Self-catering Cottages in Wales on Trip Advisor is supporting this year’s event, which will cover key issues such as: Debate: Love Story – Discover the science of attraction, its impact on the brain, and why love fades or lasts. CEO of Relate Chris Sherwood, BAFTA nominated director Martha Fiennes, and Romanticism expert Shahidha Bari rethink romance. Talk: Why Are Humans Monogamous? – Only 3 percent of mammals are monogamous. The faithful few include beavers, wolves, bats, and, of course, humans. Why is monogamy so rare? And how did this come to pass? UCL anthropologist Kit Opie takes a journey back to the beginning of human relationships. Workshop: How to Find Love Online – One in three couples now find love on the internet. Learn how to do it successfully. Creating a profile can seem daunting at the best of times. What’s the best way to be presented online? Dating expert and School of Life coach Susan Quilliam reveals the top tips for making the most of an online profile. Full details of the event program can be found on the website of the Institute of Art & Ideas at https://iai.tv. And Hay-on-Wye Accommodation information can be found on the Hideaways In Hay website at http://hideawaysinhay.co.uk. When asked about the reasons behind creating this event, the hosts of the event, Robert Rowland Smith and Shahidha Bari said: “Creating a truly unique offering in a beautiful setting where attendees can make meaningful change in their life, love and relationships was the objective. This is an empowering weekend of debates, lectures and workshops in Hay-on-Wye designed to map what is for all humanity: The Greatest Adventure.” The Institute of Art & Ideas, based in London in the UK, and the people behind the “How the Light Gets In” Philosophy & Music Festivals are launching this new Festival for Hay-on-Wye over the May Day Holiday Weekend, the first weekend in May. With the upcoming Hay Literary Festival taking place at the end of May annually (the second bank-holiday weekend in May), and attracting over 250,000 visitors and most of the world’s literary press and famous names from President Bill Clinton, Noam Chomsky, and J.K. Rowling to Margaret Atwood, Steven King, and this year, even Bernie Saunders, visiting this new May Day weekend festival earlier in the month, will be just as much fun, draw less on the pocket and have more luxury accommodation available at reasonable prices. This year’s Festival is jointly hosted by Robert Rowland Smith and Shadidha Bari: Robert Rowland Smith began his career as a Prize Fellow of All Souls College, Oxford. Now a philosopher and psychoanalyst, Robert is the author of best-selling Breakfast with Socrates: The Philosophy of Everyday Life and Driving with Plato: The Meaning of Life’s Milestones. Shadidha Bari is Former BBC New Generation Thinker and Senior Lecturer in Romanticism at Queen Mary University London. The weekend is packed with lectures from world-leading neuroscientists, philosophers and psychologists and with live music from emerging artists. Full details on the sessions at this year’s The Greatest Adventure event can be found at https://iai.tv. The Hideaways In Hay website has Hay-on-Wye accommodation availability details at http://hideawaysinhay.co.uk. For more information, please visit http://hideawaysinhay.co.uk


12 Months on: European Commission Present Updates on GDPR Timelines and Objectives at 7th Annual Biobanking Industry Summit Legal advisor and policy analyst to provide opening keynote on the Impact of the General Data Protection Regulation (GDPR) on collaborative science in Europe. London, United Kingdom, April 29, 2017 --( Adopted in April 2016, the EU General Data Protection Regulation is a legal framework for the protection of personal data and will effect biobanks in terms of how they collect, store and/or process human biological samples alongside other forms of sensitive personal information such as genetic and health data.* With an expertise in European public affairs and legislation, Emanuele specialises in the impact of data protection rules on the research sector in Europe. Highlights from his talk at BioBanking 2017 will include a description of GDPR rationale, objectives and timelines; discussions on the impact of regulation in European research and innovation; insight into the “research exemption” rule; and progressive outlook into overcoming future challenges. The event spotlight on ethics and regulation will also feature presentations and case studies from The European Sperm Bank, UCL Baby Biobank, Nottingham Health Science Biobank and Cambridge Blood and Stem Cell Biobank. Other sessions on the agenda for Biobanking 2017 will include talks on data management solutions, bio sample management and bio sample access presented by UK Biobank, BioKryo GmbH, MHRA-NIBSC, Auria Biobank, Bayer AG and Biostor Ireland. Further information including a detailed agenda and full speaker line-up is available at http://www.bio-banking-event.com BioBanking 2017 will take place on 14th & 15th June at the Holiday Inn Kensington Forum, London UK. Sponsored by Liconic UK Ltd, Scientist.com, Thermo Fisher Scientific * Source: http://www.bbmri-eric.eu/wp-content/uploads/2016/08/BBMRI-ERIC_FAQs_on_the_GDPR_V1.0_for_print.pdf Contact Information: For media enquiries contact Teri Arri on Tel: +44 (0)20 7827 6162 / Email: tarri@smi-online.co.uk For exhibition and sponsorship enquires contact Alia Malick on Tel: +44 (0)20 7827 6168 / Email: amalick@smi-online.co.uk For all other enquires contact the team on Tel: +44 (0)20 7827 6000 or email events@smi-online.co.uk About SMi Group: Established since 1993, the SMi Group is a global event-production company that specializes in Business-to-Business Conferences, Workshops, Masterclasses and online Communities. We create and deliver events in the Defence, Security, Energy, Utilities, Finance and Pharmaceutical industries. We pride ourselves on having access to the world’s most forward thinking opinion leaders and visionaries, allowing us to bring our communities together to Learn, Engage, Share and Network. More information can be found at http://www.smi-online.co.uk London, United Kingdom, April 29, 2017 --( PR.com )-- SMi Group are delighted to have Emanuele Barbarossa, European Commission Legal Adviser & Policy Analyst, present on the General Data Protection Regulation (GDPR) in an opening keynote address at the 7th annual BioBanking conference which returns to Central London this June.Adopted in April 2016, the EU General Data Protection Regulation is a legal framework for the protection of personal data and will effect biobanks in terms of how they collect, store and/or process human biological samples alongside other forms of sensitive personal information such as genetic and health data.*With an expertise in European public affairs and legislation, Emanuele specialises in the impact of data protection rules on the research sector in Europe. Highlights from his talk at BioBanking 2017 will include a description of GDPR rationale, objectives and timelines; discussions on the impact of regulation in European research and innovation; insight into the “research exemption” rule; and progressive outlook into overcoming future challenges.The event spotlight on ethics and regulation will also feature presentations and case studies from The European Sperm Bank, UCL Baby Biobank, Nottingham Health Science Biobank and Cambridge Blood and Stem Cell Biobank. Other sessions on the agenda for Biobanking 2017 will include talks on data management solutions, bio sample management and bio sample access presented by UK Biobank, BioKryo GmbH, MHRA-NIBSC, Auria Biobank, Bayer AG and Biostor Ireland.Further information including a detailed agenda and full speaker line-up is available at http://www.bio-banking-event.comBioBanking 2017 will take place on 14th & 15th June at the Holiday Inn Kensington Forum, London UK. Sponsored by Liconic UK Ltd, Scientist.com, Thermo Fisher Scientific* Source: http://www.bbmri-eric.eu/wp-content/uploads/2016/08/BBMRI-ERIC_FAQs_on_the_GDPR_V1.0_for_print.pdfContact Information:For media enquiries contact Teri Arri on Tel: +44 (0)20 7827 6162 / Email: tarri@smi-online.co.ukFor exhibition and sponsorship enquires contact Alia Malick on Tel: +44 (0)20 7827 6168 / Email: amalick@smi-online.co.ukFor all other enquires contact the team on Tel: +44 (0)20 7827 6000 or email events@smi-online.co.ukAbout SMi Group:Established since 1993, the SMi Group is a global event-production company that specializes in Business-to-Business Conferences, Workshops, Masterclasses and online Communities. We create and deliver events in the Defence, Security, Energy, Utilities, Finance and Pharmaceutical industries. We pride ourselves on having access to the world’s most forward thinking opinion leaders and visionaries, allowing us to bring our communities together to Learn, Engage, Share and Network. More information can be found at http://www.smi-online.co.uk Click here to view the list of recent Press Releases from SMi Group


News Article | April 25, 2017
Site: www.sciencedaily.com

How lithium-ion (Li-ion) batteries behave under short-circuit conditions can now be examined using a new approach developed by a UCL-led team to help improve reliability and safety. The use of high energy density Li-ion batteries is ubiquitous -- from powering portable electronics to providing grid-scale storage -- but defects can lead to overheating and explosions. Although catastrophic failure is extremely rare, recent high-profile cases including the recall of Samsung's Galaxy Note 7 smartphone line and the grounding of an aircraft fleet highlight why it's important to understand battery failure. "In previous work, we've tracked Li-ion battery failure caused by extreme heat in 3D and real-time, but this is the first time we've tracked what happens to the temperature and structure of cells when we short circuit the battery in a controlled way at an internal location of our choosing, initiating a series of potentially dangerous events," explained first author, Dr Donal Finegan (UCL, NASA and NREL). "This is of particular interest, as short-circuiting is thought to be responsible for a number of high-profile, real world failures. Knowing when and where the cell will fail has allowed us to characterise what happens during catastrophic failure in-depth using high-speed X-ray imaging. This provides us with new insights to help guide the design and development of safer and more reliable Li-ion batteries." The study published today in Energy and Environmental Science involved researchers from UCL, NASA-Johnson Space Center (USA), the U.S. Department of Energy's National Renewable Energy Laboratory (NREL, USA), WMG University of Warwick, Diamond Light Source (UK), The European Synchrotron (ESRF, France) and the National Physical Laboratory (NPL, UK). To induce failure, the team inserted a device capable of generating an internal short circuit on-demand and at a pre-determined location into commercially available Li-ion batteries, which are commonly used to power portable electronics and electric vehicles. Designed and patented by U.S. researchers Dr Eric Darcy (NASA) and Matthew Keyser (NREL), the temperature-activated device allows researchers to mimic hidden defects that can occur during the battery manufacturing processes, leading to a dangerous chain reaction of heat generation and battery failure. The team used the device to gain insight into cell design vulnerabilities by causing cell walls to rupture or cells to burst open. Using high-speed X-ray imaging, researchers monitored what happened to the structure of the cells in real-time, as the short circuit drove the catastrophic failure process which propagated through cells and modules. Individual cells, as well as small cell modules, were tested under conditions that represented a worst-case battery failure scenario. Short circuits were initiated inside the batteries at ~60 degrees C. During the failure process, cell temperatures reached in excess of 1085 degrees C. From analysing the high-speed imaging frame by frame, the team looked at the effects of gas pockets forming, venting and increasing temperatures on the layers inside two distinct commercial Li-ion batteries and identified consistent failure mechanisms. Corresponding author, Dr Paul Shearing (UCL) explained: "It is fascinating to see how quickly the process of thermal runaway can spread throughout these cells, which went from being completely intact to being completely destroyed within around one second. "This investigation provides the first description of how short-circuit failure propagates inside a cell in real time, this was only possible by combining the novel short-circuiting devices developed by NASA and NREL with ultra high-speed X-ray imaging. We were surprised to learn how susceptible neighbouring cells are to propagation of thermal runaway. This demonstrates the importance of isolating failing cells within larger battery packs and modules, which may be found in a range of applications from space suits to electric vehicles." The team now plans to examine how these new insights can be used to improve the safety of commercial battery and module designs. For example, researchers will study how the rupture of the highest energy density commercial cells can be prevented and how to reduce the risk of cell-to-cell propagation.


News Article | April 26, 2017
Site: motherboard.vice.com

When thousands of football fans pour into Cardiff's Principality Stadium on June 3 to watch the final match of the UEFA Champions League, few will be aware that their faces will have already been scanned, processed, and compared to a police database of some 500,000 "persons of interest". Despite significant criticism against the technology from fans, British police will pilot a new facial recognition surveillance system at the UEFA Champions League final in Cardiff, Wales this summer. According to a government tender issued by South Wales Police, the system will be deployed during the day of the game in Cardiff's main train station, as well as in and around the Principality Stadium situated in the heart of Cardiff's central retail district. Cameras will potentially be scanning the faces of an estimated 170,000 visitors plus the many more thousands of people in the vicinity of the bustling Saturday evening city center on match day, June 3. Captured images will then be compared in real time to 500,000 custody images stored in the police information and records management system alerting police to any "persons of interest," according to the tender. The security operation will build on previous police use of Automated Facial Recognition, or AFR technology by London's Metropolitan Police during 2016's Notting Hill Carnival. "I have seen the use of AFR increase" In an email interview with the UK Government's surveillance camera commissioner Tony Porter, who in March released a national strategy on use of surveillance cameras, Motherboard was told that incidents like the recent attack on the Borussia Dortmund team bus before a Champions League quarter-final match are examples of why law enforcement organisations are looking at AFR. However, he outlined that police must utilise the technology in a measured way that is compliant with the surveillance camera code of practice. "My office has been in touch with South Wales Police to help them ensure that when deploying AFR they are complying with the code [of practice]," he said. "I have seen the use of AFR increase [over] the past few years and a recent report by the National Institute of Standards and Technology indicated that facial recognition is a difficult challenge. Getting the best, most accurate results for each intended application requires good algorithms, a dedicated design effort, a multidisciplinary team of experts, limited-size image databases, and field tests to properly calibrate and optimize the technology." But questions of effectiveness of AFR, as well as a lack of oversight, still surround the technology. South Wales Police have not responded to multiple requests for comment. Recent findings in NIST's Face In Video Evaluation program report, which the commissioner referred to, details the limitations of AFR in identifying "non-cooperative" subjects—that is, subjects who are not facing the camera or whose faces are obscured. The report finds that accurate facial recognition can only be achieved in controlled environments with high quality cameras, as a subject's face can easily be obscured for any number of reasons. It also outlines that the need for multiple cameras comes with a high computation cost. The accuracy of facial recognition software has also recently been publicly criticised in the US during a House Committee on Oversight and Government Reform. The committee revealed findings by the Government Accountability Office that algorithms used by the Federal Bureau of Investigation were inaccurate 14 percent of the time and were more likely to misidentify black people. The report was also damming of the FBI's unregulated and disproportionate use of facial recognition tech, which mirrors recent controversy caused by findings of unlawful retention of photos of millions of innocent people by UK police forces. The practical limitations of AFR are corroborated by the follow up statement issued by the Metropolitan Police concerning the Notting Hill Carnival operation. Use of AFR during the security operation led to zero arrests, failing to identify even a single person of interest despite there being a total of 454 arrests made during the course of the carnival. "The lack of legal safeguards for the public is growing wider and more alarming all the time," The limitations in the effectiveness of AFR, as well as confusion around regulations, are worrying to privacy advocates like Rachel Robinson, policy director at human rights and civil liberties campaign organisation Liberty. "The chasm between the increasingly advanced surveillance technology rolled out by police and the lack of legal safeguards for the public is growing wider and more alarming all the time," she told Motherboard via email. Robinson said that there are indeed times when targeted CCTV is necessary and proportionate, but that, "instantaneous facial recognition technology with the potential to identify anyone in a crowd of thousands, alongside ongoing police storage of huge numbers of innocent people's photographs, is a seriously intrusive combination." Despite clear issues and trepidations concerning AFR, appetite for the use of the technology by law enforcement appears to be significant. "I foresee this continuing," said Porter concerning future use of AFR by police. "In terms of additional applications I can see it linking in with other technology such as body worn video, being used along other databases and so on." This statement aligns with information contained within a financial strategy document showing that South Wales Police took a national lead in securing a £2 million grant from the Home Office through the Police Transformation Fund to be allocated to various UK police forces to spend on facial recognition systems. The £177,000 contract notice issued by South Wales Police titled "Automated Facial Recognition Solution" directly related to the UCL final states the duration of the contract to be five years; indicating that the controversial technology is certainly set to see further police deployment in the future. On April 27, South Wales Police responded to Motherboard's requests for comment. Chief Superintendent Jon Edwards, Gold Commander for event, said, "South Wales Police has secured funding from the Home Office to develop automated facial recognition technology for policing. The UEFA Champions League finals in Cardiff give us a unique opportunity to test and prove the concept of this technology in a live operational environment, which will hopefully prove the benefits and the application of such technology across policing." Subscribe to Science Solved It, Motherboard's new show about the greatest mysteries that were solved by science.


News Article | April 17, 2017
Site: www.bbc.co.uk

After two decades of development and "heartbreak", scientists are on the verge of sending missions to explore the ocean world of Europa. Could this be our best shot at finding life elsewhere in the Solar System? Orbiting the giant planet Jupiter is an icy world, just a little smaller than Earth's moon. From a distance, Europa appears to be etched with a nexus of dark streaks, like the product of a toddler's chaotic scribbling. Close up, these are revealed to be long linear cracks in the ice, many of which are filled with an unknown contaminant that scientists have dubbed the "brown gunk". Elsewhere, the surface is tortured and irregular, as if massive slabs of ice have drifted, spun and flipped over in slush. Jupiter's immense gravity helps generate tidal forces that repeatedly stretch and relax the moon. But the stresses that created Europa's smashed up terrain are best explained by the ice shell floating on an ocean of liquid water. "The fact that there's liquid water underneath the surface which we know from previous missions, in particular from the magnetometer observations made by the Galileo spacecraft as it flew past [in the 1990s], makes it one of the most exciting potential targets to look for life," says Prof Andrew Coates of UCL's Mullard Space Science Laboratory in Surrey, UK. Europa's dark, briny deep might extend 80-170km into the moon's interior, meaning it could be holding twice as much liquid water as there is in all of Earth's oceans. And while water is one vital prerequisite for life, Europa's ocean might have others - such as a source of chemical energy for microbes. What's more, the ocean may communicate with the surface through a number of means, including warm blobs of ice from below rising up through the ice shell - which could be tens of kilometres thick. So studying the surface could provide clues to what's going on deep below. Now, Nasa is priming two missions to explore this intriguing world. Both have been discussed here at the 48th Lunar and Planetary Science Conference (LPSC) in Houston. The first is a flyby mission called Europa Clipper that would likely launch in 2022. The second is a lander mission that would follow a few years later. "We're really trying to get at Europa's potential habitability, the ingredients for life: water, and whether there's chemical energy for life," he tells me. "We do that by trying to understand the ocean and the ice shell, the composition and the geology. And mixed into those is the level of current activity at Europa." Clipper carries a payload of nine instruments, including a camera that will image most of the surface; spectrometers to understand its composition; ice-penetrating radar to map the ice shell in three dimensions and find water beneath the ice shell; and a magnetometer to characterise the ocean. However, since the Galileo spacecraft provided evidence for an ocean in the 1990s, we've learned that Europa isn't one of a kind. "One of the most amazing and significant discoveries of the past decade or so in planetary exploration is that you can't swing a dead cat in the outer Solar System without hitting an ocean world," says Clipper's programme scientist Curt Niebur, from Nasa headquarters in Washington DC. At Saturn's moon Enceladus, for example, ice from a subsurface ocean gushes into space through fissures at the south pole. The saturnian satellite could also get a dedicated mission in the 2020s, but Dr Niebur believes Europa stands out: "Europa is much larger than Enceladus and has more of everything: more geological activity, more water, more space for that water, more heat, more raw ingredients and more stability in its environment." But there's something else that marks the moon out: its neighbourhood. Europa's orbital path takes it deep into Jupiter's powerful magnetic field, which traps and speeds up particles. The resulting belts of intense radiation fry spacecraft electronics, limiting the durations of missions to months or even weeks. That said, this radiation also drives reactions on Europa's surface, yielding chemicals called oxidants. On Earth, biology exploits the chemical reactions between oxidants and compounds known as reductants to supply the energy needed for life. However, the oxidants made on the surface are only useful to Europan microbes if they can get down into the ocean. Fortunately, the process of convection that pushes warm blobs of ice upwards might also drive surface material down. Once in the ocean, oxidants could react with reductants made by seawater interacting with the rocky ocean floor. "You need both poles of the battery," explains Robert Pappalardo. For scientists like Bob Pappalardo and Curt Niebur, the impending missions are the realisation of a two-decades-long dream. Since the first Europa mission concepts were drawn up in the late 1990s, one promising proposal after another has been thwarted. During the noughties, the US and Europe even pooled resources on a mission that would have sent separate spacecraft to Europa and Jupiter's larger ice moon Ganymede. But the plan was cancelled amid budget cuts, with the European part evolving into the Juice mission. "I don't think there's been a Europa mission over the past 18 years that I have not either had my fingers in or has not passed under my eye," says Curt Niebur. "It's been a long road. The road to launch is always a rocky one, and it's always full of heartbreak. We've experienced that more than most on Europa." Exploring Europa is costly - though no more so than other Nasa "flagship" missions such as Cassini or the Curiosity rover. There are inherent engineering challenges, such as operating within Jupiter's radiation belts. Spacecraft instruments need to be shielded with materials such as titanium metal but, says Dr Pappalardo, "you can only shield them so much because they have to be able to see Europa". So to keep Clipper safe, Nasa is going to stray from the rulebook somewhat. "The assumption always was: Galileo flew past Europa, so the next mission has to be an orbiter. That's just how we do business," says Dr Niebur. But rather than orbit Europa, Clipper will instead reduce its exposure to mission-shortening radiation by orbiting Jupiter, and make at least 45 close flybys of the icy moon over three-and-a-half years. "We realised we could avoid those technical challenges of orbiting Europa, make the mission much more achievable and still get the science we want if we fly past it a lot," says Clipper's programme scientist. The strength of sunlight near Europa is about a 30th of what it is at Earth. But Nasa decided it could power Clipper with solar panels rather than the radioactive generators some other outer planet missions have used. "All those years of study forced us to burn away our pre-conceptions and get us to really focus on reality, not on our wish-list... to focus on the best science," says Curt Niebur. In 2011, a National Research Council report re-stated the importance of exploring the icy moon. Even so, Nasa remained wary because of the cost. But the support on Capitol Hill has been pivotal. A Europa venture has bipartisan backing, and in Republican Congressman John Culberson - the chair of the particular House Appropriations Subcommittee with jurisdiction over Nasa's budget - the mission has had a unique champion. The 60-year-old Texan lawmaker has been entranced by Europa ever since observing it through the Celestron 8 telescope he bought himself as a high school graduation present. Over the last four years, the subcommittee he chairs has channelled money to scientists working on Europa, even when the space agency's chief wasn't asking for it. Generous investment means that much more of the technical work has been completed on Clipper than is normal for a mission at its stage (phase B) in the Nasa project cycle. The lander is at an earlier stage of development, called pre-phase A, but a report on the mission's science value was discussed at a workshop here at the LPSC. The lander has received no funding in the President's 2018 budget request for Nasa. But Dr Jim Green, director of planetary science at the agency, tells me: "That mission in particular is tremendously exciting, because it tells us the science we have to do from the surface of a moon that's really hard to get to. "We still have quite the process to go through, do the due diligence, understanding the kind of measurements we need to make. Then we'll work with the administration in the future at the right time to see if, budgetarily, we can move forward with it." Some innovative Europa lander concepts have been proposed over the last two decades, reflecting the scientific bounty to be had by touching down. Dr Geraint Jones of the Mullard Space Science Laboratory has worked on one concept called a penetrator. "They haven't been flown in space before, but it's a really promising technology," he explains. A projectile deployed from a satellite hits the surface "really hard, at about 300m/second, about 700 miles an hour", exposing pristine ice for analysis by onboard instruments, which could be designed to withstand the impact. By contrast, Nasa's forthcoming lander would put down softly with the help of the Sky Crane technology used to drop the Curiosity rover safely on Mars in 2012. During the touchdown, it will use an autonomous landing system to detect and avoid surface hazards in real time. Clipper will provide the reconnaissance for a landing site. "I like to think of it as finding that right oasis, where there might be water close to the surface. Maybe it's warm and maybe it has organic materials," says Bob Pappalardo. The craft would be equipped with a sensitive instrument payload and a counter-rotating saw to help get at fresher samples below the radiation-processed surface ice. "The lander is all about hitting the freshest, most pristine sample possible. One way to do that is to dig deep, another way is going to where there is some kind of eruption on the surface - like a plume - that's dropping very fresh material onto the surface," says Curt Niebur. In recent years, the Hubble telescope has made tentative observations of plumes of water-ice erupting from beneath Europa, much as they do on Enceladus. But there's no point in the lander going to the site of a decades-old eruption, it would need to visit the location of a much more recent plume. So scientists need to understand what's controlling these geysers: for example, Clipper will determine whether the plumes are correlated with any hot spots on the surface. Earth's seas are teeming with life, so it can be hard for us to contemplate the prospect of a sterile, 100km-plus deep ocean on Europa. But the scientific threshold for detecting life is set very high. So will we be able to recognise alien life if it's there? "The goal of the lander mission is not simply to detect life [to our satisfaction], but to convince everyone else that we have done so," Dr Niebur explains. "It does no good for us to invest in this mission if all we create is scientific controversy." Thus, the lander's science definition team came up with two ways to address this. First, any detection of life has to be based on multiple, independent lines of evidence from direct measurements. "There's no silver bullet; you don't do one measurement and say: 'aha, eureka we've found it'. You look at the sum total," says Dr Niebur. Second, the scientists have come up with a framework to interpret those results, some of which might be positive, while others negative: "It creates a decision tree that marches through all the different variables. Following all these different paths, the end result is: yes, we've found life, or no we haven't," he says. At the lander workshop here at the LPSC, Nasa's Kevin Hand described the process as "biosignature bingo". Now, the team will have to see if the scientific community is persuaded. Curt Niebur explains: "I want to have that discussion now, today, years before we launch so that we can all be focused on analysing the data once we land."

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