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June 2011 Archives

Facebook poll

By James Dacey

July’s edition of Physics World will be celebrating all things relating to the science of invisibility. IOP members will be able to view this special issue tomorrow from MyIOP.org.

In one of the features, physicist and Hollywood adviser Sidney Perkowitz reflects on how invisible people and objects have captured the popular imagination for millennia. But we want to know your opinion on this topic. Which of the following science-fiction stories has the best use of invisibility as a plot device?

    * The Invisible Man
    * Star Trek
    * Predator
    * Harry Potter
    * Lord of the Rings
    * The Ring of the Nibelung
    * Heroes
    * Hollow Man

Go to the Physics World Facebook page to vote for one. And feel free to add a comment if your favourite book or film is not included.

Last week’s poll addressed the topic of particle physics. We asked our Facebook followers: If the LHC or the Tevatron fail to find the Higgs, should the world invest in a new machine to continue the search?

It seems that the majority of respondents are keen on big physics and the pursuit of fundamental answers because 78% voted yes.

We also had a number of comments from our fans. And interestingly, the majority of feedback came from our fans who voted no. Bengt Månsson who lives in Partille, Sweden, for instance, explains why he would not favour another expensive collider. “If LHC fails then it is rather probable that there is something wrong/unfinished with the theory.”

Marc Merlin, a fan based in Georgia in the US, did not vote either way. He did make some interesting points, however, that go right to the heart of the situation in the US where the Tevatron collider at Fermilab will be closed at the end of September. “This is a really tough question, and it can only be reasonably discussed in the context of budgets and competing science objectives,” he said. “The physics goals would be alluring, but what would pursuing a successor to the LHC mean in terms of other important research being deferred or even cancelled?”

We’re looking forward to some lively debates about your opinions relating to this week’s poll.

By Matin Durrani in Perth, Australia

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If there’s one issue dominating Australian politics right now, it’s the proposed tax on emissions of greenhouse gases.

It seems a genuine attempt to encourage Australia – probably the world’s highest per capita emitter of carbon dioxide – to slow down or halt its growth in emissions.

Unfortunately, the climate-change debate in Australia is lagging well behind that in the rest of the world, with the media giving way too much attention to those “climate sceptics” who remain unconvinced that rising levels of greenhouse gases in the atmosphere are changing the Earth’s climate.

We’re not talking about providing airspace to the relatively small band of genuine scientists who are questioning particular aspects of the scientific evidence for climate change, based on a thorough knowledge of the relevant research.

Instead, the Australian media seems to be focusing on one character in particular: a certain Lord Monckton, deputy leader of the UK Independence Party.

This is the man who, apart from claiming that global warming stopped in 2001, likened the Australian federal government’s chief climate-change adviser Ross Garnaut of the University of Melbourne to a Nazi for his views on global warming, a below-the-belt accusation for which he was forced to apologize earlier this week.

Yesterday, however, as I was nearing the end of my week-long fact-finding tour of Australian science, who else should be appearing in the Perth district than Monckton himself.

He was invited to deliver the Lang Hancock Lecture at Notre Dame University in Fremantle, just south of Perth on Thursday night. Unfortunately, the university press office declined a request to attend to the event that was put in by one of the other journalists on the tour I’m on.

Monckton’s visit had already caused a fair bit of noise, including a formal complaint from more than 50 Australian scientists, who called for the lecture to be cancelled. Despite the protests, the lecture went ahead as planned, as did a separate talk at the Association of Mining and Exploration Companies annual convention on Math Lessons for Climate-Crazed Lawmakers

To me there’s no point calling for Monckton’s views to be stifled, which only adds to his martyr status and makes it appear that climate scientists have something to hide and are too scared to see the topic out in the open.

What’s needed instead is a careful unpicking of his main points, such as those offered here

That was certainly the view taken a few years ago in the UK by the likes of former science adviser David King. It’s the path that Australia needs to go down too.

But the controversy has not reached the end of its course. Monckton is also due to speak on 4 July in the chemistry department at the University of Western Australia. However, UWA president Alan Robson, who I met for lunch today, has insisted that the talk was not endorsed by the university but that it had been organized by a local community group that merely chose to use the department as a venue.

The row looks set to go on.

Subverting science

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By Matin Durrani in Perth, Australia

Donna Franklin's Fibre reactive hybrid dress

Donna Franklin’s Fibre reactive
hybrid dress
, 2004–2008

If you think Australia is remote from the rest of the world, well the city of Perth is even more cut-off, being a five-hour flight from Sydney and 1000 km from the next main centre of population.

That remoteness has engendered a kind of “wild west” spirit, where people have the time and space to think up radical ideas that might be more quickly dismissed in less isolated places.

That, at least, was the view of the Nobel-prize-winning microbiologist Barry Marshall from the University of Western Australia (UWA) – best known for proving that most ulcers are caused by certain bacteria called Helicobacter pylori. Marshall was talking to me over lunch at the university on the latest leg of my week-long fact-finding tour of Australian science that I’m on with three fellow European science journalists.

The subversive spirit was echoed after lunch by Ionat Zurr, an Israeli-born artist working at UWA within SymbioticA – a self-styled “artistic laboratory” within the School of Anatomy and Human Biology that describes itself as being “dedicated to the research, learning, critique and hands-on engagement with the life sciences”.

Unlike most art–science projects, which involve artists reinterpreting scientific ideas in an artistic form, the people at SymbioticA are getting their hands dirty by learning various experimental scientific techniques to create works of art.

Projects include making loudspeakers from bones, growing edible steak from artificial tissue, and (well before Lady Gaga had a similar idea) creating wearable dresses from fungus leaves (pictured above).

SymbioticA, which was founded in 2000 after fighting off a rival bid to buy a boring old confocal microscope, seeks to question the very nature of science, art and even life itself. It also wants to demystify and “democratize” the scientific laboratory.

The delightfully garrulous Zurr admitted that not everyone understands, or even approves of, what she and her colleagues are trying to do. What, you may ask, is the point of designing jewellery made from pig wings grown from bone-marrow stem cells?

But the strong reaction of some scientists to SymbioticA surely shows that she and her fellow artists must be doing something right: after all, isn’t science itself about challenging orthodox thinking? Perhaps scientists are happy to be subversive but don’t like being subverted themselves.

As one of my fellow science journalists complained, shaking his head in derision as we left: “They should have bought that microscope.”

By Matin Durrani, Sydney, Australia

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Australia is a big country but, as far as science is concerned, it does just about as much one might expect for a country with a population of just 23 million.

But according to Thomas Barlow, a former academic and journalist who is now a kind of freelance policy wonk and science adviser, Australians are far too pessimistic about their scientific future. In other words, while Australians believe they are an inherently inventive people, they are less good, or so the thinking goes, at capitalizing on their smart ideas.

I met Barlow yesterday during my visit to Sydney at the home of Peter Pockley – a veteran Australian science journalist and broadcaster who also regularly reports on Australian science for Physics World.

Barlow has outlined his thoughts in his 2006 book The Australian Miracle, which offers an honest, well written and sober perspective on Australian science.

It’s worth reading if you’re at all interested in the country’s science and Barlow has as good a perspective as any – he’s married to Michelle Simmons, who’s a leading quantum-computing physicist at the University of New South Wales and who directs a successful national Centre for Quantum Computer Technology funded by the Australian Research Council.

Still, I just can’t get away from the nagging feeling that Australia, being physically so far removed from the US, Europe, China, Japan and other centres of power in global science, is destined to always remain one step behind the rest of the world.

In his book, Barlow denies that there is a brain drain of talent from Australia, which may be true. But unless there is a steady flow of people and ideas in and out of the country, true innovation may struggle. And being so far away, that flow is simply hard to sustain.

Neutrino mixing angles from T2K and MINOS
Neutrino mixing angles from T2K and MINOS

By Hamish Johnston

Less than a fortnight ago we brought you news that the T2K experiment in Japan has caught the first glimpse of muon neutrinos changing (or oscillating) into electron neutrinos as they travel 300 km under Japan.

Now researchers at the MINOS experiment in the US have seen the same neutrino oscillation. The MINOS physicists sent a beam of neutrinos more than 700 km underground from Fermilab in Chicago to the Soudan Underground Laboratory in Minnesota. At Soudan, the team detected a total of 62 electron neutrinos, which is 13 more than they should have seen if some muon neutrinos had not changed to electron neutrinos.

Neutrinos exist in three “flavours” – muon, electron and tau – that change or “oscillate” from one to another as they travel in space. The oscillation strength between different types of neutrino is characterized by three “mixing angles” – known as theta-12, theta-23 and theta-13. Theta-12 and theta-23 have already been measured but theta-13 requires the observation of the muon-electron neutrino oscillation.

More data are required before theta-13 can be nailed down – you can see the uncertainties in the T2K and MINOS results in the diagram. Then physicists will try to measure the same quantity for anti-muon and anti-electron neutrinos. Comparing the two angles could help physicists understand why there is much more matter than antimatter in the universe.

You can read Fermilab’s announcement here.

Avoiding the grump

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Phil Diamond

By Matin Durrani, Marsfield, Australia

There’s someone who says he’s going to be “in a grump” if the Square Kilometre Array (SKA) is not built in Australia. That’s Phil Diamond (above), head of astronomy and space science at the country’s Commonwealth Scientific and Industrial Research Organisation (CSIRO).

Diamond took up his post last year after moving from the University of Manchester in the UK, where he was director of the Jodrell Bank Centre for Astrophysics and co-ordinator of PrepSKA – the preparatory study for SKA itself.

I caught up with Diamond earlier today at CSIRO’s radiophysics laboratory at Marsfield, about 20 km north-west of Sydney, where I’m on a fact-finding tour of Australian science with three other European science journalists. The newly appointed CSIRO chief is obviously keen for SKA to be built in Australia, having upped sticks from the UK, but unfortunately the Australian plan is faced with a rival bid from various nations in southern Africa.

Both bidders are planning to construct an array of some 3000 radio-telescopes, about a third of which (in the Australian case) will be located in an area about 5 km across in the remote outback in the west of the country, with about a half distributed over another 180 km, with the final fifth spread over several thousand kilometres (including some as far away as New Zealand).

Given that the smallest object a telescope can resolve is inversely proportional to its diameter, spreading lots of dishes far apart means that SKA will have a really high “resolving power”.

And the big advantage of locating SKA in the outback is that there will be hardly any radio interference from mobile phones, power lines or other effects of modern civilization. That’s because almost no-one lives there: the shire of Murchison, where the central SKA core will be located, has a population of just 110 spread over an area that’s 20% bigger than the whole of the Netherlands. And the lack of interference is essential given that the radio emissions that SKA’s interested in are so weak that, says Diamond, it’s like having to detect the signal from an airport radar located 50 light-years away from Earth.

So the Australians think they have quite a strong case, but no doubt the Africans do too and the final decision will be made on 29 February 2012 by the international astronomy community spearheaded by the SKA project office, which is based in Diamond’s old haunt of Jodrell Bank. Not that anyone is suggesting any bias of course.

One thing both bids are having to deal with is the huge amount of information spewing out from the array – with 2 terabits of data per second from each dish, we’re talking the equivalent of a kilometre-high stack of CDs every minute. That information has to be filtered and then sent down high-performance optical cables to a central data centre.

And the point of the project? Oh, just the small matter of finding out how the first black holes and stars formed, how galaxies evolve, the nature of dark energy, the origin of cosmic magnetic fields, the nature of gravity under extreme conditions and possibly even whether we are alone in the universe.

Plus whoever wins will have the world’s astronomers knocking on their doors. So you can see why Diamond will be in a grump if it doesn’t work out for Australia.

Physicsworld.com wins at the online media awards

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Me (James Dacey, right) receiving the award from Noel Young, one of the judges

By James Dacey

I was absolutely delighted to be in London on Thursday night on behalf of physicsworld.com, to receive the award for Best Specialist Site for Journalism at the Online Media Awards. It was humbling just to be shortlisted for the award alongside the likes of popular sports sites Espn.com and foxsports.com – but to win was really fantastic!

The awards, which are sponsored by the Press Association, are said to “identify the best and boldest of online news-based creativity and also the most original.” Websites in the different categories were assessed by a panel of 11 judges based in a number of countries including the US, China and Australia.

Other winners included bbc.co.uk and theguardian.co.uk, which shared the award for Best Site For News-Led Journalism. And the biggest haul of the evening went to thesundaytimes.co.uk, which took six awards including Best Video Journalism and Best Campaigning/Investigative Journalism.

The award ceremony was held at the swanky Marriott Hotel in Kensington and the opening address was given by Gordon Young, editor of The Drum, the magazine that organized the event. “We believe that online media is really becoming a discipline on its own,” he said. “It’s important to establish an event that gets down to the business of comparing like with like and really celebrating and appreciating the very best of these skills.”

Flattering words indeed! I have to admit that I wasn’t entirely convinced that we’d win the prize, largely because we were up against some websites with far more general remits. But it’s great that a specialist site like ours can occasionally get recognition from the mainstream. Of course, it helps that it’s a really exciting time for physics right now. You’ve got particle physicists closing in on exciting new understandings of nature at the Tevatron and the LHC. Then there are exoplanet hunters who seem to be discovering new alien worlds every other day. I could go on.

But online media – including videos and embedded audio clips – is bringing new opportunities for us to tell these exciting stories to new audiences in different ways. We’ve plunged headfirst into digital publishing in the last few years, having existed as a print publication for over two decades. Who knows how you will be able to digest Physics World content two decades from now. But whatever form it takes, I’m sure it will be the fascinating stories from the world of physics that will give the magazine its enduring appeal.

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By Matin Durrani, Sydney, Australia

It’s a tough life, but someone had to do it.

I’m here in Sydney with three other European science journalists after accepting an invitation from Australia’s Department for Foreign Affairs and Trade to take part in a week-long fact-finding tour of the country on the theme of “science and innovation”.

We’re being introduced to a range of Australian scientists and later this week are flying to Perth before being taken to the proposed site for the main component of the Square Kilometre Array (SKA). SKA is a set of radio-telescopes that will either be built in Australia and New Zealand or possibly in southern Africa. A choice is set to be made between the two competing bids by the international astronomy community on 29 February 2012.

The Australian government has a regular programme of inviting journalists from around the world to help showcase the country’s efforts in a range of different themes, not just science. You can’t blame them for making the effort. After all, Australia is just so far from the rest of the world – it’s a five-hour flight from Sydney to Perth alone – that a well-crafted programme of events is what’s needed to encourage busy journalists to give up their time to find out more.

So over the next few days I’ll be keeping you up to date with events Down Under. In the meantime, I hope you enjoy the photo I took from Circular Quays as an early Sunday-morning passenger ferry from Manly approaches me with the iconic Sydney harbour bridge in the background.

Australians have been moaning about all the poor weather they’ve been having in the last week or two, but all I can say is that having left the UK late last week, the Sydney winter seems as good as the summer I left behind.

I won’t make you jealous by showing what the beaches look like – oh, go on then (see below).

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Cassini enhanced and false-coloured image of Enceladus backlit by the Sun shows the fountain-like plumes of the fine spray of material that spews from the south polar region (Credit: NASA/JPL/Space Science Institute)

Cassini’s enhanced and false-coloured image of Enceladus backlit by the Sun shows the fountain-like plumes of the fine spray of material that spews from the south polar region (Courtesy: NASA/JPL/Space Science Institute)

By Tushna Commissariat

Enceladus, Saturn’s sixth largest moon is back in the news as the Cassini-Huygens mission has managed to directly sample the water plumes jetting into space from its southern polar region. These plumes of ice and salt originate from the moon’s famed “tiger stripes” region – four parallel giant fissures on the southern face of the moon.

The findings from these fly-throughs are the strongest evidence yet for the existence of large-scale saltwater reservoirs beneath the moon’s icy crust. “Enceladus is a tiny icy moon located in a region of the outer solar system where no liquid water was expected to exist, because of its large distance from the Sun,” says Nicolas Altobelli, ESA’s project scientist for the Cassini-Huygens mission. “This finding is therefore a crucial new piece of evidence showing that environmental conditions favourable to the emergence of life may be sustainable on icy bodies orbiting gas-giant planets.”

Indeed, the moon has been described previously by other Cassini researchers as one of the “most habitable spots beyond Earth in the solar system for life as we know it”.

Enceladus’ water plumes are though to contribute towards replenishing Saturn’s outermost and faint E-ring, which traces the orbit of Enceladus around Saturn. The Cassini spacecraft discovered the plumes in 2005 and more recently has been able to fly directly through them.

During three of Cassini’s passes in 2008 and 2009, its Cosmic Dust Analyser measured the composition of freshly ejected plume grains. The icy particles hit the detector target at speeds of 6.5–17.5 km/s, and vaporized instantly. Electrical fields inside the instrument then separated the various constituents of the resulting impact cloud for analysis.

Researchers looking at the data from the detector have found that grains ejected in the plumes and into the atmosphere of the moon and out towards the E-ring are relatively small and mostly salt-poor, closely matching the composition of the E-ring. However, closer to the moon itself relatively large, salt-rich ice grains were found.

This mosaic of 21 Cassini images is a false colour full-disc view of the anti-Saturn hemisphere on Enceladus (Credit: NASA/JPL/Space Science Institute)

This mosaic of 21 Cassini images is a false colour full-disc view of the anti-Saturn hemisphere on Enceladus (Courtesy: NASA/JPL/Space Science Institute)

Scientists explain this by saying that more than 99% of the total mass of ejected solids is in salt-rich grains, but most of these are heavy and fall back to the moon, so never make it into the E-ring. The salt-rich particles have an “ocean-like” composition which indicates that most, if not all, of the expelled ice comes from liquid saltwater body somewhere under the surface, rather than from the icy face of the moon.

The scenario envisioned by the team goes something like this – deep underneath Enceladus’ surface, perhaps 80 km down, there is a reservoir of water between the rocky core and the icy mantle, kept liquid by tidal forces generated by Saturn and its neighbouring moons, as well as by the heat generated by radioactive decay. When the outermost layer cracks open, the reservoir is exposed to space. The drop in pressure causes the liquid to evaporate, with some of it flash-freezing into salty ice grains: together these create the plumes.

When salty water freezes slowly, the salt is squeezed out, leaving pure water ice behind. So, if the plumes were coming from the surface ice, there should be very little salt in them. “There currently is no plausible way to produce a steady outflow of salt-rich grains from solid ice across the tiger stripes other than from saltwater under Enceladus’ icy surface,” says Frank Postberg, Universität Heidelberg, Germany, who is the lead author of a Nature paper announcing these results.

Have your say by taking part in our reader polls

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By James Dacey

Like many I was initially quite sceptical about the value that social media could add to journalism. To the uninitiated just “dipping their toe” into the likes of Facebook and Twitter it can seem like an unrelenting stream of throwaway remarks. But I’m starting to realize that, used effectively, social media can offer certain things that go beyond traditional journalism. One of the real positives of social media is its ability to break down boundaries and connect with audiences.

Physics World has existed in various social media formats for some time now, and we are keen to explore ways of engaging with readers using social media. One mini project we have tried recently is to run a series of polls on our Facebook page relating to hot topics within the physical sciences. This week we asked about a topic that never fails to provoke opinions: climate change. It is an issue that grabbed the headlines again recently after it emerged that several Australian climate researchers have received death threats on account of their research.

So we asked our Facebook followers if they believe it is realistic to think that the science and politics of climate issues can ever be truly separated. While I was perhaps not surprised by the outcome, I was surprised by its decisiveness as 93% of respondents said “no” – these issues cannot be separated. Of course, it is highly reductionist to boil such a complicated issue down to a simple yes/no response. But that’s why we are encouraging you to offer your comments too when taking part in the poll.

Our latest poll concerns particle physics. The community is geared up for an important few months as the LHC continues to perform well and Fermilab’s Teveatron will close at the end of September after a dazzling career. What we want to know is the following: If the LHC or the Tevatron fail to find the Higgs boson, should the world invest in a new machine to continue the search?

To take part in the poll then go to our fanpage on Facebook. And, as I said, feel free to add a comment to explain your reasons!

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By Hamish Johnston

What’s your favourite number, and does the fact that you are interested in physics inform your choice?

I have been thinking about this today after hearing an interview on BBC radio with the mathematics writer Alex Bellos, author of the book Alex’s Adventures in Numberland, or Here’s looking at Euclid if you are in North America.

Bellos (right) has launched an online survey asking people for their choices and the reasons behind their picks. He also requests for a small amount of biographical information.

What did I say? Three, because of the old adage “Two’s company, three’s a crowd”. Although a small number, three is fascinating because it can cause very large problems in social settings.

Three is also interesting from a physics point of view. Solving problems involving three bodies is much more difficult than those involving two. And then there’s the Efimov effect, whereby a group of three particles will bind together, even though pairs of the constituent particles will not.

How about you, perhaps it’s one over the fine-structure constant (137) or Avogadro’s number?

You can read more about the project and listen to an interview with Bellos here.

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Krauss will bring cosmology into the humanities

By James Dacey

The physicist and popular-science author, Lawrence Krauss, will join a star-studded array of academics to teach at a private university in London called the New College for the Humanities.

The new university is the brainchild of A C Grayling, a philosopher at the University of London, who is well known in the UK through his regular appearances in the media. Grayling says the university will bring a much needed boost to the arts and humanities in the UK, which are being squeezed in state-supported universities due to budget cutbacks. Its business model takes inspiration from the US Ivy League universities as students will pay £18,000 a year for tuition fees – double the maximum that most UK universities can charge.

Students will be offered a very broad syllabus and will be encouraged at every turn to take a critical outlook. They will be treated to lectures by world-leading academics including Richard Dawkins who will teach evolutionary biology and science literacy, and Stephen Pinker who will cover philosophy and psychology.

Among this dream team will be Lawrence Krauss, the author of Physics of Star Trek and several other popular-science books. He told me that he plans to give an introduction to the modern view of the universe, and he will touch on other subjects, including quantum mechanics. “Science literacy will play a large part in the program, as it should,” he said. “A literate person should have the same kind of fluency in the ideas of science that they have in the arts and humanities.”

Krauss says that he will pitch the course to be understood by students with little scientific background. “Based on my teaching experience at a variety of US institutions, I believe one can proceed rather far in this regard with minimal background – with motivated students it should be fun” he said.

But not everybody in the UK has been as enthusiastic as Krauss about Grayling’s new venture. Since the philosopher announced his plans for the new university at the beginning of June, he has been attacked by critics who have dismissed the venture as elitist or opportunistic. Last week, both Grayling and Dawkins were both confronted by angry protesters during public lectures, with Grayling’s talk being evacuated after a smoke bomb was let off. Even the Mayor of London, Boris Johnson, has chirped in with a letter to the Telegraph in which he labels the university as “rejects college” – for rich kids who weren’t bright enough to get into Oxford and Cambridge.

Grayling has since struck back by emphasizing the fact that 30% of students will be offered financial support, funded largely by the fees of the wealthier students. He also argues that foreign students at state-funded universities already pay in the region of £18,000, and many universities have been increasing their overseas student intake for some time. You can read Grayling’s full arguments expanded in this opinion piece published in the Independent yesterday.

So I bid Lawrence good luck. But with continuing criticism, including a big thumbs down from the president of the National Union of Students, it may not be plain-sailing. The celebrity professors will have to use all their brain power to win the hearts and minds of the British public.

The lunar eclipse as Physics World readers saw it

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By James Dacey

Skygazers in many parts of the world were treated yesterday to the longest total lunar eclipse in over a decade. Sadly, here in the south-west of England almost complete cloud cover meant that I saw precisely none of it. It was rotten luck and Google’s “live coverage‘“of the eclipse felt like a very poor second best.

But thankfully my spirits were lifted this morning when I saw these two splendid photographs sent to us by readers via the Physics World Facebook page. The first image was taken by Pedram Esfahani, an engineering physics student based in Tehran, Iran, who captured this shot of the Moon just before the total eclipse.

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This second photo taken by Jawaid Siddiq in Lahore, Pakistan, also shows the Moon just before the total eclipse at 0910 GMT (0110 local time).

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In the second image you can see that the shadowy region takes on a slightly red hue. This effect (as I’m sure you’ve all been explaining to your non-physicist friends) is due to the way light interacts with the Earth’s atmosphere. To reach the Moon during an eclipse, light has to pass around the Earth and light at the blue end of the spectrum tends to be scattered by the atmosphere. But light at the red end of the spectrum, with its relatively longer wavelengths, has a much better chance of sneaking through and reaching the Moon, before it is then reflected back to Earth.

Totality – when the lunar face is completely blocked – lasted from 1922 GMT until 2102 GMT, making it the longest total eclipse since July 2000. The diagram below was created by NASA to show the extent to which the eclipse was observable across the planet.

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You can see a larger version of this diagram with the different eclipse stages explained at NASA’s official eclipse website. The site also gives details of the eclipses coming up during the rest of the year, with the next event to add to your calendar being a partial solar eclipse on 1 July.

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Temperature and humidity graph from Wichita, Kansas (Courtesy: AccuWeather)

By Margaret Harris

I grew up in Kansas, where unusual weather isn’t so much a conversation topic as a spectator sport. But even by Kansas standards, what happened in Wichita (the state’s largest city) last Thursday night was decidedly weird.

As the graph shows, shortly after midnight on 9 June, the temperature in Wichita jumped from 85 to 102 °F (roughly from 30 to 40 °C) in less than 20 minutes. At the same time, the relative humidity plunged, dropping from 55% to a desert-like 7%. Two hours later, both readings had returned to “normal” – or at least, as normal as Kansas weather ever gets.

What happened in Wichita is known as a “heat burst”, and it occurs when a pocket of air in the upper atmosphere collapses, producing a hot, dry downdraft and winds in excess of 60 miles per hour. Such bursts can be seriously damaging: when a meteorologically similar (but colder and wetter) event called a microburst hit a neighbourhood in my hometown back in the late 1990s, it flattened houses as efficiently as any tornado. But how did the air pocket get there in the first place?

The answer (courtesy of this excellent post from John Rennie of The Gleaming Retort blog) turns out to involve one of my favourite weather phenomena: virga, the high-altitude rain that leaves grey streaks across the sky as the moisture evaporates before reaching the ground. This evaporation process pulls heat out of the surrounding air, leaving it colder and denser. If this pocket of air becomes more dense than the air below it, it falls.

But as Rennie notes, that doesn’t explain the heat and low humidity in Wichita’s heat burst. For that, we need some more physics. As a parcel of cold, dense air falls, it becomes even more dense because it gets squeezed by the higher-pressure air present at lower altitudes. This squeezing does work on the parcel, heating it adiabatically. But of course, heating air causes it to expand, and as a result, most potential bursts never hit the ground. Instead, the competing influences of pressure and temperature cancel each other out, the parcels reach an equilibrium at some altitude, and any excess heat is absorbed by the surrounding air. Wet air is particularly good at this, thanks to the high heat capacity of water vapour.

In Wichita, however, the air seems to have been falling too fast to achieve any kind of equilibrium. It was also falling through a relatively dry layer of atmosphere, so there wasn’t much water vapour around to absorb the heat it generated as it fell. The result was the hot, dry “whoosh” shown in the graph.

I should warn you that there are probably some holes in this explanation, since downbursts of all types (wet, cold, hot, dry) are still poorly understood. But the next time you wake up hot and thirsty in the middle of a strange wind storm, relax:it may just be Kansas weather up to its usual tricks.

D0 fails to reproduce CDF’s mysterious bump

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By James Dacey

In April the CDF collaboration at the Tevatron triggered excitement and frantic speculation when it announced the discovery of a mysterious bump in its data that could not be explained by the Standard Model of particle physics. But alas, it appears that this mysterious bump will now fade into the night, following the announcement today by the D0 collaboration – CDF’s sister experiment – that it has failed to reproduce the result.

Two months ago the CDF collaboration reported the unexplained signal, which was spotted in a study of W and Z boson pairs that are created when protons and antiprotons collide in Fermilab’s Tevatron collider. The researchers noted a bump between 120 and 160 GeV /C2 in the jets of W bosons with a statistical significance of about “three sigma”.

Within days, speculation surrounding CDF’s bump was rife. People quickly ruled out the possibility that this was the elusive Higgs boson, but some were suggesting that it could be explained by a kind of hybrid force dubbed “technicolour”. A separate theory, proposed by Dan Hooper at Fermilab, was that the excess of events could be explained by a new force responsible for interactions between dark matter and normal matter.

And excitement grew even stronger last week when further analysis by the CDF collaboration saw the significance of its result upgraded to almost five sigma. In everyday terms, this means that there was just a one-in-a-million chance of the bump being due to a statistical fluke.

But earlier today, the D0 collaboration may have killed the party following its analysis of a similar data selection. Publishing a related paper on their website and on arXiv, the researchers report that they find no evidence for the same rare boson production in the mass range 110–170 GeV/c2.

In a statement published on Fermilab’s website, D0 co-spokesperson Dmitri Denisov is quoted as saying: “Our data for collisions that produce a W boson plus two jets are in agreement with the predictions from the Standard Model.

“We have looked among two hundred trillion particle collisions, and we don’t see the excess reported by CDF.

The D0 collaboration will report its result and the details of its analysis at 4 p.m (CDT). today at a seminar at Fermilab. You will be able to watch a live webcast.

So is this the end of the bump? I’m not sure but it will be very interesting to hear what CDF makes of the developments.

If Einstein met Confucius

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By James Dacey

An exhibition about the life and work of Einstein will no longer appear in Shanghai following a fracas between Chinese and Swiss museums. The exhibition has been touring China as part of a celebration of 60 years of diplomatic relations between Switzerland and China.

According to the Associated Press, the show’s organizers from the Historical Museum of Bern were unhappy with plans of Shanghai’s Science and Technology Museum. The would-be hosts had apparently wanted to merge the Einstein show with a separate exhibit of comparable size about the great Chinese philosopher Confucius who lived more than 2000 years earlier.

With the Historical Museum of Bern yet to issue a public statement, the precise details of the disagreement remain somewhat hazy. But the developments have left me pondering what the great physicist himself would think about having an exhibition of his life’s achievements lined up alongside those of Confucius.

Indeed, Einstein was clearly far more than a great physicist. He was also a man deeply engaged in the social issues of his time, which was no doubt influenced by his own position – being a Jewish scientist living in Europe during the rise of Nazi Germany.

Although Einstein’s guiding principle seems to have been the wonder of science, it is hard not to think that he would have admired some of the ideas of Confucius. For instance, I’m sure that Einstein would have shared some of Confucius’ ethical concerns, especially his idea that individuals should strive towards moral perfection.

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Einstein said as much in 1950 during a conversation with Reverend C. Greenaway, a minister in New York. “The most important human endeavour is the striving for morality in our actions. Our inner balance and even our very existence depend on it. Only morality in our actions can give beauty and dignity to life.”

Where the two men may have disagreed, however, is their view of humanity and collective human behaviour. Confucianism holds that through communal endeavour, humans are mouldable and perfectible. Einstein, on the other hand, appears to have taken a more hardened outlook, perhaps influenced by some of the events of his time.

“I don’t believe that humanity as such can change in essence, but I do believe it is possible and even necessary to put an end to anarchy in international relations,” he said in 1919 to Hedwig Born, the wife of Max Born, when talking about how individual states may have to give up their autonomy.

So I’m not saying that Einstein’s reflections on social philosophy and morality should overshadow his scientific achievements. But I just don’t think the idea that a Chinese museum would merge a showcase about his life with an exhibit about Confucius is such a weird idea. This is especially so given the influence Confucianism has had on political life in China.

By Michael Banks

Unobtanium, collossium and fibonaccium. Those were just some of your suggestions for the name of element 112 following its confirmation two years ago.

In the end researchers, led by Sigurd Hofmann and his group at the Centre for Heavy Ion Research (GSI) in Darmstadt, Germany, went for copernicium, which was finally approved by the International Union of Pure and Applied Chemistry (IUPAC) in July 2009.

Now we want your suggestions for two new elements – 114 and 116 – after they were added to the periodic table following a three-year review by the IUPAC, which develops standards for naming new elements and compounds.

Currently element 114 is known as ununquadium with element 116 named ununhexium.

The elements were spotted by researchers at the Joint Institute for Nuclear Research (JINR) in Dubna, Russia, back in 2004, but only confirmed last year by scientists at the Lawrence Berkeley National Laboratory in California and the GSI lab.

Researchers at the JINR will now get the chance to name the new elements. They will submit their suggestions to the IUPAC who will then publish them on its website for six months giving scientists and the public time to scrutinize and comment on the new name.

So physicsworld.com readers what are your suggestions?

By Margaret Harris

Some time ago, University of Nebraska biochemist Steve Caplan received an e-mail from someone who wanted to work in his lab. The e-mail’s beginning (“Dear sir”) was not encouraging, and it was all downhill from there – a morass of meaningless buzzwords and and vague suggestions that the writer wanted to “gain an opportunity to experience a dynamic, rigorous and systemic training”.

The writers of such e-mails don’t get jobs, but they do get a starring role in Caplan’s essay “How not to get a lab job: what your approach says about you”, which is available on the LabLit website. Most of the essay’s examples are hilarious, and Caplan’s “translations” of them are great.

Except for the third example. It’s not so amusing. And to anyone with the “two-body problem” of looking for jobs as one-half of a scientific couple, Caplan’s “translation” won’t seem funny at all. Here’s the job request:

Hi Dr Caplan,
My name is Dr XXX. I am research associate (assistant professor) at the University of Anywhere in the Department of Radiation and Cellular Oncology. As my husband Dr YYY moved in Omaha, I am also looking for a research position at your institute. Here I have attached a cover letter and my CV for your consideration.

Now here is Caplan’s “translation” of Dr XXX’s e-mail:

“My husband’s job is the important one – he is the “real” scientist. I just need to find a job doing anything – doesn’t matter what – somewhere near my husband. I’m not necessarily interested in what you do, but saw your advertisement…”

For good measure, this translation is accompanied by a cartoon drawn by Caplan’s 12-year-old daughter, in which a frilly-dressed woman declares “It’s my husband’s job that’s important, I’m just holding onto his tail!” while tied on a long leash to a bespectacled male scientist. Niiiice.

Watch that doggy run!

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Chihuahua pacing, captured by X-ray video (Courtesy: Martin Fischer)

By James Dacey

They have been our best friends for a long time, so surely we know everything there is to know about dogs. Wrong!

According to researchers in Germany we still have a very patchy knowledge of how dogs move. Of course, we know they scamper along on four legs, occasionally balancing on their back two when they decide to press their muddied front paws against your freshly cleaned shirt. But apparently we are still thin on details when it comes to the precise sequence of movements within their locomotive system.

To redress this situation, zoologist Martin Fischer (see picture, right) and colleagues at the University of Jena in Germany have carried out what they claim is the most extensive survey to date of dog movement. They have studied in fine detail the motions of 327 dogs from 32 different breeds by deploying a variety of imaging technologies.

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The dogs were filmed from the front and side using high-speed cameras as the animals walked using two different gaits. Following this, the dogs’ movements were captured in 3D by attaching reflecting markers to different parts their bodies before the researchers filmed them using infrared cameras. Then finally, to build a picture of the dogs’ skeletal movements, the researchers recorded the moving dogs using a high-speed X-ray video system.

One interesting discovery to emerge from the X-ray footage is that regardless of the total length a dog’s legs, its upper leg is always the same length – and this appears to be important in linking the movements of the shoulders with the lower legs. For this reason, the researchers conclude that dogs of all sizes run very similarly, whether they are a greyhound or a Schnauzer.

Another key finding relates to how different parts of a dog’s anatomy correlate with each other to enable the front and back legs to move in circular motions. Fischer and his team found that the shoulder blades and the thighs act as centres of rotation for the front and back legs, which contradicts earlier studies that had located these centres at the shoulder joint and hip.

Fischer’s group has compiled its findings and images in a newly published book, Dogs in Motion, which the researchers hope will also be of interest beyond the scientific community. “We explicitly want to reach all dog owners and people who love dogs in general,” says Fischer.

Meanwhile, in other dog-related news, a pair of researchers at Harvard University have used high-speed video combined with X-ray footage to study another aspect of canine motion – how dogs drink. Alfred Crompton and Catherine Musinsky have shown that dogs take the same approach as their arch rivals, cats, when lapping up liquids by allowing water to adhere to the tips of their tongues. Earlier work had suggested that dogs simply “scooped up” water with vigorous swipes of the tongue. Crompton and Musinsky describe their work in a paper recently published in the journal Biology Letters, and you can see the dog-drinking action in this related video.

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Martin Rees picks up the Templeton Prize from Prince Philip
(Courtesy: Clifford Shirley)

By Michael Banks

Can you guess what these two are saying to each other?

The photo, which was taken yesterday, shows the cosmologist Martin Rees from Cambridge University picking up the 2011 Templeton Prize at a ceremony at Buckingham Palace.

Rees was presented with the gong, which comes with a cheque for a whopping £1m, by Prince Philip, the Duke of Edinburgh, in a private ceremony that was also attended by seven former Templeton winners, including Paul Davis and George Ellis.

Yesterday also happened to be Prince Philip’s 90th birthday.

According to the Templeton Foundation, the prize is awarded for “progress toward research or discoveries about spiritual realities”.

The 68-year-old cosmologist was awarded it for his “profound insights” into the nature of the cosmos that have “provoked vital questions that address mankind’s deepest hopes and fears”.

There was some controversy around Rees being awarded the prize. Indeed, he told me he was “surprised” on hearing he had won and that he usually tries to avoid discussing science and religion with his views being “rather boring”.

There is not a £1m prize on offer from us, but physicsworld.com readers – can you guess what is being said between Rees (right) and Prince Philip in our caption competition?

If we have some funny submissions then we may be able to dig out a prize for the best one.

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The graph shows the distribution of the “w-jj excess” as seen by the CDF experiment (Courtesy: Punzi/Fermilab)

By Tushna Commissariat

Two months ago, in early April, the particle-physics community was rife with speculation and excitement over a “bump” – a possible new particle – in the data that Fermilab’s CDF experiment was looking at. On Monday 30 May Giovanni Punzi, a CDF collaborator, presented an update on what is now referred to the “ W-jj” bump, as a part of his talk at the 23rd Rencontres de Blois Particle Physics and Cosmology conference currently being held in France. The update says that the bump is seen in more recent data with an even larger statistical significance.

At the time, CDF was looking for slightly rare di-boson pairs – W bosons produced in association with another W or a Z boson. It noted a bump between 120 and 160 GeV /C2 in the jets produced in the collisions with a statistical significance of about “three-sigma”, which meant that the result would not be considered valuable until a “five-sigma” statistical significance could be established. The new data, however, have established a significance that is officially “closer to five sigma” (unconfirmed sources suggest it is as close as 4.8) and that “it was not just a statistical fluctuation” and that it is now a “serious issue for CDF to understand this”, according to Punzi.

Interestingly, Punzi’s slides also say that it is almost impossible that bump is due to the Standard Model top-quark background, as suggested by some theoretical papers, as that would imply that previous measurements for SM top-quark background had huge errors. The next step forward would be if CDF’s sister experiment D0 or the LHC’s ATLAS or CMS experiments, none of which have found the bump in their data so far, manage to detect it.

This updated result has seen a variety of responses from physicists.

Adam Falkowski, who writes the Resonaances blog, seems rather jubilant. “In a collider experiment, such a huge departure from a Standard Model prediction is happening for the first time in the human history,” he writes. “I don’t have to stress how exciting it is.”

Peter Woit, author of the Not Even Wrong blog, feels that while a five-sigma significance is important, problems with background modelling might thwart the result. “The signal is being extracted from a huge background, so a small misunderstanding of the background could be its cause.” Only a detection of the same result by another experiment would make the case more compelling, according to him.

Tommaso Dorigo, a blogger and CDF collaborator, is still sceptical of the result and chalks it up to bad background modelling, like Woit. “No, it is not the Higgs. And it is not a new particle. It is, in my humble opinion, a problem in the modelling of backgrounds, one which was unnoticed before only because it is small enough to have escaped previous attempts at “tuning” the simulations.”, he writes in his blog.

So while it seems like we the path to “new physics” is full of “bumps”, the field of particle physics is a rather exciting one right now! Take a look at the slides Punzi used for his talk here.