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Kaikoura: ‘Most complex quake ever studied’

PapateaImage copyright
JOHN ELLIOTT/LEEDS UNI/COMET

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New wall: Whole blocks of ground were lifted upwards

The big earthquake that struck New Zealand last year may have been the most complex ever, say scientists.

November’s Magnitude 7.8 event ruptured a near-200km-long swathe of territory, shifting parts of NZ’s South Island 5m closer to North Island.

Whole blocks of ground were buckled and lifted upwards, in places by up to 8m.

Subsequent investigations have found that at least 12 separate faults broke during the quake, including some that had not previously been mapped.

Writing up its findings in the journal Science, an international team says the Kaikoura event, as it has become known, should prompt a rethink about how earthquakes are expected to behave in high-risk regions such as New Zealand.

“What we saw was a scenario that would never have been included in our seismic hazard models,” said Dr Ian Hamling from the country’s geophysics research agency, GNS Science.

Media captionDrone footage of the Papatea fault crossing State Highway 1

At issue was the way the quake was able to rupture so far along its path, to produce such a big magnitude.

Starting in South Island’s North Canterbury region, the crustal failure moved eastwards and northwards along the coast to Marlborough Province, before then petering out offshore. In the process, the quake managed to straddle two major fault networks.

The behaviour challenged some long-accepted ideas. One of these is the notion that ruptures cannot jump large separations between individual fault segments.

Five km is considered something of a limit. But in the Kaikoura event, substantially larger step-overs were recorded.

How this was possible is not fully explained, says Prof Tim Wright from Leeds University, UK.

“We think the main reason was some very large stress changes introduced early in the earthquake that then triggered the later segments to fail,” he told the Science In Action programme on the BBC World Service.

“There were also in this case some faults we didn’t know about, even though New Zealand has one of the best fault maps in the world; and so some of these big jumps were facilitated by motion on faults we didn’t know were there. But in many cases, there are genuine gaps of 15-20km.”

Media captionProf Tim Wright: “The Kaikoura quake broke the rules”

The team believes the exceptional nature of the Kaikoura event raises questions about how the risk of future quakes is assessed. Some of the assumptions that go into building seismic models now need to be revisited, the group argues.

In terms of magnitude, only December’s M7.9 event in Papua New Guinea was bigger in 2016. Given the level of shaking produced in the New Zeland quake, it is remarkable there were so few deaths (“just” two) and injuries. Hundreds of people in the town of Kaikoura itself did though have to be evacuated because landslides had cut local roads.

Also astonishing was the scale of “surface expression”. Giant fissures opened in the ground, highways were broken by metres-long offsets, beaches rose up from the sea, and railway lines were lifted high into the air.

Image copyright
HAMLING ET AL

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Walking the faults: Multiple techniques are used to study quakes – on the ground and from space

One of the most photographed areas was the countryside around the Papatea fault.

“You can call it bonkers; it’s certainly a real puzzle,” said Dr Hamling. “It’s a block of material of about 50 sq km that’s been thrust up out of the ground by about 8m and then pushed south by 4-5m.

“To try to model it in the traditional way is almost impossible; it’s very hard to explain how you can get this thing to pop up in the manner that it has.”

Image copyright
Philip Carthew/GNS

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Earthquakes can be studied using satellite radar images. They will trace the amount of ground movement. In the Kaikoura event, parts of northern South Island moved by about 6m horizontally with an uplift of about 8m

To understand the complexity of the Kaikoura quake, the scientists used a range of techniques, including mapping with satellite interferometry.

This works by finding the difference in “before” and “after” radar images of the Earth taken from orbit. It allows even quite subtle ground movements to be detected, including in those areas where the surface itself has not been ripped apart.

The team was able to call on two different systems – the Sentinel-1 spacecraft operated by Europe, and the Alos platform owned by the Japanese.

“Alos’s longer radar wavelengths allow us to see through the vegetation; we can see the tree trunks rather than the leaves and they’re much more stable for making deformation maps,” explained Prof Wright.

“However, with Sentinel’s shorter wavelengths you get much more detail, which allows us to narrow down exactly where the deformation has occurred.”

Media captionThree cows left stranded by the quake became an internet sensation

Article source: http://www.bbc.co.uk/news/science-environment-39373846

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Europa: Our best shot at finding alien life?

View of Europa taken in the 1990s by the Galileo spacecraftImage copyright
NASA/JPL-Caltech/SETI Institute

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Europa holds a vast, salty ocean beneath its fractured ice shell

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, extending in some cases for thousands of kilometres. Many are filled with an unknown contaminant that scientists dub 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 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.

Image copyright
NASA/JPL-Caltech

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Europa Clipper will make at least 45 flybys of the jovian moon during its primary mission

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. So studying the surface could provide clues to what’s going on in the ocean.

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.

Dr Robert Pappalardo, from Nasa’s Jet Propulsion Laboratory, is Clipper’s project scientist.

“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.

Media captionProf Andrew Coates explains why Europa is a good place to look for life beyond Earth

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 reacting with the rocky ocean floor.

“You need both poles of the battery,” explains Robert Pappalardo.

Image copyright
NASA

Image caption

Artwork (not to scale): Europa in cross-section, showing processes from the seafloor to the surface (Europa Lander Study 2016 Report)

For scientists like Dr Pappalardo, 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 program 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, following the cancellation of the US-European mission, a National Research Council report restated the importance of exploring the icy moon. Even so, Nasa remained wary because of the cost.

Image copyright
NASA/JPL/University of Arizona

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Four views of Europa’s surface from the Galileo mission, clockwise from top left: (1) disrupted ice crust in the Conamara region; (2) crustal plates, which are thought to have broken apart and “rafted” into new positions; (3) reddish bands; (4) an impact structure about the size of Hawaii

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 House Appropriations Subcommittee, which has 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.

Media captionDr Geraint Jones explains how to punch through the hard icy surface of Europa

“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.

Image copyright
NASA/JPL-Caltech

Image caption

Nasa’s Europa lander could determine whether there was or is life on the jovian moon

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.”

Follow Paul on Twitter.

Article source: http://www.bbc.co.uk/news/science-environment-38925601

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Bloodhound record bid slips again

CarImage copyright
BLOODHOUND SSC

The British-led effort to break the World Land Speed Record is going to slip again – to 2018.

The Bloodhound Super-Sonic Car was supposed to go racing later this year, to try to raise the current mark of 763mph (1,228km/h) to over 800mph.

But what are described as “short-term cash flow problems” have put a dent in the schedule.

The upside, says the team, is that it provides additional time to eke more power from the car’s rocket.

Engineers want some extra thrust margin just in case the final build of the vehicle turns out to be heavier than expected.

“It’s frustrating, I know; and the team are disappointed but we’re resilient and we’re going to make this happen,” Bloodhound director Richard Noble told BBC News.

“The money is coming in but it doesn’t always match our planning and fit with the times when we need it.”

Fashion backing

In the meantime, the project’s education programme, which delivers STEM activities to schools, continues apace. Nearly 100,000 children have participated in the last year, developing their knowledge of maths and physics by constructing and running mini rocket cars.

Bloodhound has signed some big sponsorship deals recently, notably with the Chinese auto manufacturer Geely. This cleared all debts.

Mr Noble said he was also in the process of inking two more – one with a major IT company, and another with a leading fashion brand.

But the time it takes for deals to be agreed, for contracts to be signed, and for money then to flow sometimes leaves Bloodhound cash-short, he explained.

“I’m reasonably happy now that we’ll be able to make our budget this year, which is great – and that means we will be on the desert, running the car, probably in mid-summer 2018.”

The car itself is all but finished. It was put on static display in October 2015, and then stripped down for a final re-assembly, with fluids, and checks.

Image copyright
BLOODHOUND SSC

The plan now is for Bloodhound to do its slow-speed testing (about 200mph) on the runway at Newquay Aerohub in late summer/autumn this year.

A specific date has yet to be announced but it will follow the completion of some “tie down” investigations, in which the car is held in place while its EJ200 Eurofighter jet engine is taken up to speed.

The jet is what will get the car rolling for its assault on the land speed record when it eventually gets to the race track on Hakskeen Pan in Northern Cape, South Africa. But it is the grunt from a rocket that will push the vehicle through the sound barrier and up to 800mph.

Bloodhound’s partner on this is the Norwegian aerospace and defence company Nammo.

It is providing in the first instance what is termed a monopropellant rocket. Monopropellants work by pumping High Test Peroxide over a catalyst. This decomposes the liquid to produce super-hot steam that is then vented through a nozzle.

More performance

Nammo has been testing rockets that have produced 30 kilonewtons of thrust. But Bloodhound’s engineers would like to get closer to the rockets’ expected monopropellant thrust ceiling of 40-45kN.

This would yield some margin in performance if the final assembly of the car turns out to be significantly heavier than the anticipated 7.5 to 7.75 tonnes.

“The car’s weight has fluctuated between 200 and 500 kilos from where we thought we were going to be. It’s something of a moving feast; we’re weighing the car as we’re building it,” said chief engineer Mark Chapman.

“But if the figures turned out to be pessimistic, we’d look pretty stupid if we turned up at Hakskeen Pan and could only do 680mph. So, the thought was: let’s be sure we can get to the speeds we want.

“Nammo are confident they can deliver a 45kN motor. They’ll test that motor later this year and then we’ll test it in-car next year.”

The Bloodhound project was launched in 2008. Back then, the thought was a new record bid would be made in 2011. But the scale of this land speed attempt has dwarfed all previous efforts.

‘Bloodhound effect’

Richard Noble was the director for the Thrust SSC car when it set the current world record in 1997. He says just £2.48m in cash was spent to achieve its supersonic mark.

In contrast, the cash spend on Bloodhound is likely to be in the region of £60m. On top of this are a whole host of in-kind contributions, which include the loan of EJ200 engines from the Ministry of Defence and the consultancy work that comes with them from Rolls-Royce.

The companies and scientific institutions involved all speak of a “Bloodhound effect”.

The two universities – Swansea and the West of England – who helped to design the car say there has been a big rise in the numbers applying to take their aerospace and engineering courses.

Likewise, engineering firms such as Castle in Glasgow, which has made the aluminium wheels for Bloodhound, say they have found it much easier to attract apprentice applications – a boost it attributes directly to the Bloodhound association.

Article source: http://www.bbc.co.uk/news/science-environment-39379499

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Dinosaur crater’s clue to origin of life

Yucatan PeninsulaImage copyright
Tim Peake/Nasa/ESA

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The crater is buried partly offshore and partly onshore, under Mexico’s Yucatan Peninsula

The crater made by the asteroid that killed off the dinosaurs is revealing clues to the origins of life on Earth.

Scientists have drilled into the 200km-wide Chicxulub crater now buried under the Gulf of Mexico.

They say its rocks show evidence of having been home to a large “hydrothermal system”, where hot fluids flowed through cracks and fissures.

Similar systems, generated by impacts on the early Earth, could have helped kickstart the first lifeforms.

The hydrothermal system at Chicxulub may have been active for two million years or more, the scientists say.

Dr David Kring, from the Lunar and Planetary Institute in Houston, is one of the researchers who discovered and reported the crater’s location.

“The impact generated a very large subsurface hydrothermal system,” he told BBC News.

“That’s exciting because we are using Chicxulub as a proxy for other, large impact events very early in Earth’s history when we think these kinds of systems might have been crucibles for pre-biotic chemistry and the habitats for the evolution of the earliest life on our planet.”

About 829m of Chicxulub core material was drilled between May and June 2016. Since then, team-members have been hard at work examining rocks from the crater which was punched in the crust by a 15km-wide space object some 66 million years ago.

The drilling project targeted an area called the peak ring, which contains the rocks that moved the greatest distance in the impact.

Image copyright
PAul Rincon

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A sample of the core drilled from the Chicxulub peak ring; about 829m of core material was recovered

At a briefing here at the Lunar and Planetary Science Conference (LPSC) in Texas, Prof Sonia Tikoo, who studies palaeomagnetism, said the cores had given scientists a lower bound for how long this hydrothermal system lasted.

The direction of Earth’s magnetic field flips every few hundred thousand years. When the Chicxulub extinction event occurred it had the reverse polarity to today.

“One thing that was very intriguing was that there were several samples in the breccia melt sequence that had what’s now the normal polarity – the same direction as what we have today,” the Rutgers University, New Jersey, scientist said.

“Three hundred thousand years [after the impact] the Earth’s magnetic field crosses over and assumes the ‘normal’ polarity – it has the opposite direction [to that which existed at the time of the imapct]. These rocks must have acquired their magnetisation during one of these normal polarity times that came later. Since the first of these happened 300,000 years later – that provides a lower bound constraint for the hydrothermal system, telling us how long hot fluids were going through the crater.”

The whole system may at first have been too hot for even the most heat-tolerant microorganisms. However, as time went on, the peak ring would have cooled down, allowing tiny lifeforms to exploit the chemicals dissolved in the hot fluids for fuel.


Chicxulub Crater – The impact that changed life on Earth

Image copyright
NASA

Image caption

The outer rim (white arc) of the crater lies under the Yucatan Peninsula itself, but the inner peak ring is best accessed offshore

  • A 15km-wide object dug a hole in the crust 100km across and 30km deep
  • This bowl then collapsed, leaving a crater 200km across and a few km deep
  • Its central zone rebounded and relaxed, producing an inner “peak ring”
  • Today, much of the crater is offshore, buried under 600m of sediments
  • On land, it is covered by limestone deposits, but its outline is visible
  • It is evident in an arc of famous sinkholes referred to as cenotes

Image copyright
Max Alexander/B612/Asteroid Day

Image caption

Mexico’s famous sinkholes (cenotes) have formed in weakened limestone overlying the crater


“With regard to the hydrothermal system, we’ve been able to deduce the mineralogy that the hot water fluids produced,” said Prof Tikoo.

“We’re starting to track, in time, the thermal evolution: how hot the waters got and we’ve been able to watch how they cool down.

“Eventually, they get cool enough to support thermophilic and hyperthermophilic organisms – the same type of biota that live at volcanic hot springs. These would have lived within the fractures and the veins of this subsurface impact crater.

“We don’t know how diverse this population will be. Is it two species that persists for millions of years? Or will we see an explosion of life so that we suddenly see 15 or 30 or 50 species?”

The asteroid impact killed off 75% of species on Earth, including the dinosaurs.

Debris thrown into the atmosphere probably saw the skies darken and the global climate cool. It may also have triggered raging wildfires. But why this environmental cataclysm killed off some groups such as the dinosaurs, while allowing birds and mammals, for example, to survive remains unclear.

“The differential survival of animals on the planet – we don’t know why birds survived and why turtles and some types of reptiles survived,” pondered Prof Tikoo. “But based on this borehole, we are going to get some limits on important parameters like energy, like trajectory – and all of that is data that will carry us towards those answers.”

The project to drill into Chicxulub Crater was conducted by the European Consortium for Ocean Research Drilling (ECORD) as part of the International Ocean Discovery Program (IODP). The expedition was also supported by the International Continental Scientific Drilling Program (ICDP).

Article source: http://www.bbc.co.uk/news/science-environment-39361007

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Major shake-up suggests dinosaurs may have ‘UK origin’

T Rex SkullImage copyright
Millard H. Sharp

Image caption

The shake-up means savage, meat-eating dinosaurs such as Tyrannosaurus rex get reclassified

The first dinosaurs may have originated in the Northern Hemisphere, possibly in an area that is now Britain.

This is one of the conclusions of the first detailed re-evaluation of the relationships between dinosaurs for 130 years.

It shows that the current theory of how dinosaurs evolved and where they came from may well be wrong.

This major shake-up of dinosaur theory is published in this weeks’s edition of the journal Nature.

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‘New’ wave-like cloud finally wins official recognition

asperitasImage copyright
Gary McArthur

Image caption

The wavy ridges of the rare asperitas cloud

Twelve “new” types of cloud – including the rare, wave-like asperitas cloud – have been recognised for the first time by the International Cloud Atlas.

The atlas, which dates back to the 19th Century, is the global reference book for observing and identifying clouds.

Last revised in 1987, its new fully-digital edition includes the asperitas after campaigns by citizen scientists.

Other new entries include the roll-like volutus, and contrails, clouds formed from the vapour trail of aeroplanes.

Collector’s item

Since its first publication in 1896, the International Cloud Atlas has become an important reference tool for people working in meteorological services, aviation and shipping.

The first edition contained 28 coloured photographs and set out detailed standards for classifying clouds. The last full edition was published in 1975 with a revision in 1987, which quickly became a collector’s item.

Now, embracing the digital era, the new atlas will initially be available as a web portal, and accessible to the public for the first time.

The World Meteorological Organisation (WMO) publishes the atlas, and also has the final say on the contents, including the addition of “new” clouds and cloud features.

This time around 12 new terms have been added. The best known of these is asperitas, meaning rough-like in Latin, as the clouds can look like the tossing of the waves at sea when viewed from below.

Image copyright
Ivica Brlić

Got a great picture of clouds or other weather phenomenon you’d like to share? Sign up to be a BBC Weather Watcher.


These clouds were first recorded over Iowa in the US in 2006, but soon a torrent of similar images from around the world began to pour in to the Cloud Appreciation Society, a citizen science body.

They began to lobby the WMO for official recognition of the cloud type. But the fact that it has now been officially included came as something of a surprise.

“Back in 2008, I thought the chances of this becoming official were really minimal,” said Gavin Pretor-Pinney, president of the society.

“At first the WMO were saying they had no plans to do a new edition, but over time I think they began to realise there is an interest among the public in clouds and there is a need for that interest to be an informed one, there’s a need for this authoritative work.”

Asperitas becomes the first addition of a new recognisable term since 1953. In addition several other supplementary features of clouds have also been added including cavum, cauda (known as a tail cloud), fluctus and murus (known as a wall cloud).

In terms of the way the WMO classifies clouds, they have also added one new “species” – the volutus, or roll-cloud, a low horizontal tube-shaped cloud mass that appears to roll about a horizontal axis.

Image copyright
Mirosalv Chichanowicz

Image caption

An example of a roll cloud or volutus which has now been added to the atlas

A key element in the evolution of the atlas has been the impact of technology. People all over the world are able to capture and exchange images on their smart phones of fleeting cloud formations.

“People don’t have to be an official weather observer, they don’t have to be schooled in the finer points of the International Cloud Atlas, they just go ‘that’s amazing’ and take a picture and send it to us, and being in the centre of that network we can spot a pattern,” said Gavin Pretor-Pinney.

The atlas also includes a recognition of the processes that can lead to cloud formation, so the clouds that arise from wildfires are now classified as flammagenitus.

Similarly patches of cloud that are formed over forests and over waterfalls are classified, but also one of the most widely seen features in the sky, contrails formed from the exhausts of airplanes, are given greater recognition.

“In the modern day you will look up to the sky and see clouds made by airplanes. Once they are made they can linger for days,” said BBC meteorologist John Hammond.

“It’s one example of how crucial knowledge of cloud physics is – it’s not just an aesthetic, our knowledge of clouds is still fairly limited.”

The new atlas also recognises some weather features that not everyone might agree can be seen as clouds. These include rainbows, halos, snow devils and hailstones.

“There is a blurred edge between what is a cloud and what is a sheet of hail falling from the sky,” said John Hammond.

“There are grey areas around the edge of this. All types of optical effects can be defined as clouds, be they halos or snow devils or rainbows, but I’m a little bit old-fashioned and I struggle with the inclusion of rainbows as clouds.”

Image copyright
Ernie Johnson

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Weather phenomena like snow devils have now been included in the atlas

Hammond believes that there will be many new entries in the future as long as the public remains engaged in the subject and he believes the opening up of the atlas via a web portal is a very good thing towards that end.

Gavin Pretor-Pinney from the Cloud Appreciation Society agrees that opening up the atlas is a huge positive.

“The value of the atlas is that it draws our attention to the sky and by learning the name of the formations, that is the way we pay attention to and value what we see around us.

“By giving a language to the forms of our atmosphere we are helping people to value our atmosphere and to pay attention our impact on it.”

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Article source: http://www.bbc.co.uk/news/science-environment-39351843

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Fossil named after Sir David Attenborough

Cascolus ravitisImage copyright
Siveter et al

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Cascolus ravitis has been reconstructed as a virtual fossil, revealing every detail of the animal

A 430-million-year-old fossil discovered “frozen in time” in ancient volcanic rock has been named after Sir David Attenborough.

The tiny crustacean, measuring less than 1cm long, was found by researchers in Herefordshire.

It has been named Cascolus Ravitis, the first word a Latin rendering of the Old English equivalent to Attenborough.

Ravitis is is a reference to Roman name for Leicester, where Sir David lived on the city’s university campus.

The fossil was given its name by researchers from the universities of Oxford, Leicester, Yale and Imperial College London.

Sir David said: “The biggest compliment that a biologist or palaeontologist can pay to another one is to name a fossil in his honour and I take this as a very great compliment.”

The fossil is the latest in a long list of species and objects to be named after the famous naturalist and broadcaster.

Others include:

  • A pygmy grasshopper species named Electrotettix attenboroughi found in 2014 preserved in amber in the Dominican Republic
  • A long-beaked echidna given the name Zaglossus attenboroughi which lives in the forested areas of New Guinea
  • A rare butterfly named Euptychia attenboroughi, in honour of his love for butterflies, which live in tropical forests in places like Colombia and Brazil
  • A flightless weevil from Indonesia was given the name Trigonopterus attenboroughi
  • A species of wildflower named the Attenborough Hawkweed discovered in the Brecon Beacons
  • Dinosaur Attenborosaurus conybeare – a type of plesiosaur which lived millions of years ago
  • A polar research ship called the RRS Sir David Attenborough – which was given his name despite the title “Boaty McBoatface” topping a public vote.
Media captionThe researchers presented Sir David Attenborough with a high resolution image of the fossil they named in his honour

Sir David, who turned 90 in May last year, grew up on the campus of the former University College Leicester where his father Frederick was the principal.

Lead researcher Prof David Siviter, from the University of Leicester, said Sir David had inspired his interest in natural history.

He said one of the reasons Sir David became a great naturalist was by collecting Jurassic rock fossils in the Leicester countryside.

The newly discovered creature is a tiny arthropod – a group of animals that includes modern insects, spiders, shrimp, and crayfish.

Prof Siviter said the fossil found in the rocks had been “frozen in time” by volcanic ash.

“It’s like an undersea Pompeii,” he told BBC News.

It was so well preserved, the research team were able to use 3D computer modelling to show its features – including minuscule eyes, delicate antennae, multiple jointed limbs and a tough exoskeleton.

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Article source: http://www.bbc.co.uk/news/science-environment-39348150

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Sea otters ahead of dolphins in using tools

Sea otters use rocks to crack open shellfishImage copyright
Jessica Fujii

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Sea otters use rocks to crack open shellfish

Sea otters may have been using stone tools for thousands or even millions of years, according to scientists.

It appears otters learned how to use tools long before other marine mammals.

Sea otters are often seen floating on their backs, using rocks to break open shellfish for food.

A genetic study of more than 100 wild sea otters living off the Californian coast suggests their ancestors living millions of years ago showed this behaviour.

Dolphins in Australia have been seen to use sponges to protect their noses when scouting for fish on the sea floor.

However, this seems to be a relatively new invention, happening less than 200 years ago.

Dr Katherine Ralls of the Smithsonian Conservation Biology Institute in Washington, US, said they were surprised to find sea otters using tools were not from the same family group, suggesting the behaviour originated in the ancestors of modern sea otters.

“It’s older in sea otters,” she told BBC News. “They’re very smart; they’ll use rocks as anvils and as hammers.”

Unlike dolphins, using tools seems to be innate in all young sea otters, said the researchers.

“Orphaned otter pups raised in captivity exhibit rudimentary pounding behaviour without training or previous experience, and wild pups develop tool-use behaviour before weaning regardless of their mother’s diet type,” they wrote in the Royal Society journal Biology Letters.

The sea otter is found along the coasts of the Pacific Ocean in North America and Asia.

They were once hunted for their fur almost to extinction.

Early in the 20th Century only 1,000 to 2,000 animals remained. Sea otters are now protected by law.

The researchers plan to study fossil remains of sea otters to confirm when the behaviour emerged.

They think depressions in the chests of some modern otters – thought to be from holding rocks on their chests – might be present in fossil specimens.

Tool use has been observed in a range of animals, including crows and primates.

“Sea otters provide a fascinating opportunity to investigate how genetic predispositions, learning, and environmental conditions contribute to a species’ capacity to use foraging tools,” said Dr Christian Rutz, an evolutionary ecologist at the University of St Andrews, who studies tool use in Hawaiian crows and New Caledonian crows.

“It is particularly exciting that otter pups express rudimentary tool behaviour in captivity without any demonstration or training. We have seen similar developmental patterns in our experiments with young crows.”

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Article source: http://www.bbc.co.uk/news/science-environment-39339424

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Plans for coal-fired power plants drop by almost half in 2016

coal stationImage copyright
Getty Images

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This new Chinese coal-fired plant opened in January but many more have been put on hold

Twenty-sixteen saw a “dramatic” decline in the number of coal-fired power stations in pre-construction globally.

The authors of a new study say there was a 48% fall in planned coal units, with a 62% drop in construction starts.

The report, from several green campaign groups, claims changing policies and economic conditions in China and India were behind the decline.

However, the coal industry argues the fuel will remain essential to economic growth in Asia for decades to come.

Rapid swing

Between 2006 and 2016, India and China together accounted for 85% of the coal plants built around the world.

But according to the Boom and Bust 2017 report, put together by Greenpeace, the Sierra Club and CoalSwarm, there has been a huge swing away from coal in these two countries in just 12 months.

Image copyright
Getty Images

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The study says that questions over finance are threatening coal plants in India

The main causes of the decline are the imposition of restrictive measures by China’s central government – with the equivalent of 600 coal-fired units being put on hold until at least 2020.

The Indian go-slow was prompted, according to the authors, by the reluctance of banks to provide funds. Work at 13 locations is currently not going ahead.

However, there have also been significant retirements of coal plants in Europe and the US over the past two years, with roughly 120 large units being taken out of commission.

“This has been a messy year, and an unusual one,” said Ted Nace, director of CoalSwarm.

“It’s not normal to see construction frozen at scores of locations, but central authorities in China and bankers in India have come to recognize overbuilding of coal plants as a major waste of resources.

“However abrupt, the shift from fossil fuels to clean sources in the power sector is a positive one for health, climate security, and jobs. And by all indications, the shift is unstoppable.”

The study comes as other groups analyse the potential for investments in coal to become stranded assets if governments continue to restrict CO2 emissions. The International Energy Agency (IEA) says that hundreds of billions of dollars could be at risk.

“The decline in new coal plants in Asian countries is truly dramatic, and shows how a perfect storm of factors is simply making coal a bad investment,” said Paul Massara, now of North Star Solar but a former CEO of RWE npower.

Image copyright
Getty Images

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Investments in solar power in India have soared in recent years

“Growing awareness of the air pollution problems coal causes, the impact of policies to tackle climate change, and the rapid growth and cost-competitiveness of renewable sources of energy, along with emerging battery technologies, are making new coal plants redundant before they are even built,” he said.

However, the World Coal Association vehemently disagrees. It says the complexity of large infrastructure projects means that until they break ground, it’s no surprise if they don’t go ahead.

“Yes, China, is reducing the number of coal-stations but not because it’s transitioning away from coal. Instead, the new dynamics is a signal of a more developed economy,” said Benjamin Sporton.

“Contrary to the picture being portrayed by certain quarters, China’s climate pledge suggests that coal will continue to be central to its energy solutions, albeit through efficiencies including the use of new coal technologies.

“In India’s case, it’s simply not true that renewables are displacing coal. The International Energy Agency has said that India’s coal demand will see the biggest growth over next five years with an annual average growth rate of 5% by 2021.

“For these countries, excluding coal from the energy mix is not an option; it is essential for economic growth and critical in securing energy access.”

According to the authors of the study, the slowdown brings the possibility of keeping global warming under 2 degrees C since pre-industrial times “within feasible reach.”

However, the study says that much more progress needs to be made to reduce the number of coal-fired plants under development in Vietnam, Indonesia, Turkey, Japan and elsewhere.

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Article source: http://www.bbc.co.uk/news/science-environment-39342818

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Spaceport protest delays rocket launch in French Guiana

A handout photo released on 14 February 2017 shows the liftoff of flight VA235, Ariane 5 ECA, from the Spaceport in Kourou, French Guiana, France, 14 February 2017Image copyright
EPA

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The Ariana 5 rocket during a previous launch

The launch of a French rocket from a space centre in French Guiana has been delayed after workers erected barricades as part of a labour dispute.

The Ariana 5 rocket was due to take a South Korean satellite and a Brazilian satellite into orbit later on Tuesday.

But the booster could not be rolled to the launch pad because of the protest at the Guiana Space Center over what workers for energy company EDF said were “deplorable working conditions”.

The launch has been moved to Wednesday.

Workers used tyres and wooden pallets to erect barricades at the facility in French Guiana.

Satellite launch company Arianespace said in a statement that “due to a social movement, it was not possible to carry out today’s [Monday's] scheduled transfer of the launch vehicle from the Spaceport’s Final Assembly Building to the launch zone.”

It said that the launch vehicle, as well as the satellites had been “placed in a stand-by mode and are being maintained in fully safe conditions”.

The two satellites, owned by Brazil and South Korea respectively, aim to improve internet access to remote communities in Brazil and provide a range of video and data services over East and Southeast Asia.

It is not the first time industrial action has delayed a launch at the Kourou Space Centre.

In 2011, another Ariana 5 rocket launch had to be moved back when workers demanded extra pay for working on Sundays.

Article source: http://www.bbc.co.uk/news/world-latin-america-39330971

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