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Neonicotinoids at ‘chronic levels’ in UK rivers, study finds

River WaveneyImage copyright
Geograph/Adrian Cable

Image caption

River Waveney’s pollution limit was exceeded for a whole month, the report said

Rivers across the country are “chronically polluted” with pesticides believed to pose a threat to bee populations, a report has found.

The River Waveney on the Norfolk/Suffolk border was found to have the highest levels of neonicotinoids in the UK.

The River Wensum in Norwich, and the River Tame in the West Midlands were also named among the most polluted.

A growing number of studies have linked the pesticides to problems for bees.

According to figures from UK monitoring data by the European Environment Agency, 88% of sites in Britain were contaminated with neonicotinoids.

The Angling Trust, the charity Buglife, and The Rivers Trust said eight rivers in England – including the Ouse, Somerhill Stream, Wyke Beck, Ancholme, and Sincil Dyke – exceeded recommended chronic pollution limits.

The River Waveney’s pollution limit was exceeded for a whole month, they said.

Image copyright
Geograph/Dave Ferguson

Image caption

The River Wensum was “chronically polluted”, the report said

The study said the three toxins of concern were imidacloprid, clothianidin and thiamethoxam, which are used in farming and waste water treatment plants.

Matt Shardlow, chief executive of Buglife, said: “We are devastated to discover that many British rivers have been heavily damaged by neonicotinoid insecticides.

“It is vital that action is taken to ban these three toxins.”

Prof Dave Goulson, from the School of Life Sciences at the University of Sussex, said just a teaspoon of imidacloprid was enough to give a lethal dose to 1.25b honeybees.

“To find that they are washing through our rivers is very serious indeed,” he said.

Image copyright
Geograph/Gillie Rhodes

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Professor Dave Goulson said just a teaspoon of imidacloprid was enough to give a lethal dose to 1.25b honeybees

Environment Secretary Michael Gove last month said tougher restrictions on neonicotinoid pesticides were justified by the growing weight of scientific evidence they are harmful to bees and other pollinators.

The Secretary of State said, unless the scientific evidence changes, the government will maintain these increased restrictions post-Brexit.

It followed advice from the UK government’s advisory body on pesticides.

Article source: http://www.bbc.co.uk/news/uk-england-suffolk-42354947

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Star system has record eight exoplanets

Kepler-90Image copyright
NASA

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Artwork: the Kepler-90 system is the first to tie with our Solar System in number of planets

Nasa has found a distant star circled by eight planets, equal to the complement in our own Solar System.

It’s the largest number of worlds ever discovered in a planetary system outside our own.

The star known as Kepler-90, is just a bit hotter and larger than the Sun; astronomers already knew of seven planets around it.

The newly discovered world is small enough to be rocky, according to scientists.

“This makes Kepler-90 the first star to host as many planets as our own Solar System,” said Christopher Shallue, a software engineer at Google, which contributed to the discovery.

Star’s seven Earth-sized worlds set record

Engineers from Google used a type of artificial intelligence called machine learning to find planets that were missed by previous searches.

Image copyright
NASA

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Kepler-90 and our Solar System compared

Image copyright
NASA

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Artwork: The Kepler telescope was launched to detect new worlds using the “transit method”

The discovery was based on observations gathered by Nasa’s Kepler Space Telescope.

Its parent star is very distant, lying 2,545 light-years away. But its planetary system appears to be ordered in a similar way to our own.

Andrew Vanderburg, a co-discoverer at the University of Texas at Austin, said: “The Kepler-90 star system is like a mini version of our Solar System. You have small planets inside and big planets outside, but everything is scrunched in much closer.”

To give a sense of how close, the outermost planet in the system orbits at around the same distance the Earth does from the Sun.

Because the new world, dubbed Kepler-90i, is so much further in – it completes one circuit of its star every 14.4 days – it’s estimated to have a scorching hot surface temperature of around 425C.

The machine learning technique was also used to find a new Earth-sized planet, called Kepler 80g, around a different star.

Some 3,500 exoplanets – worlds circling other stars – have been documented in recent decades.

Follow Paul on Twitter.

Article source: http://www.bbc.co.uk/news/science-environment-42356305

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Sumatran rhino ‘hanging on by a thread’

Ipuh at the Cincinnati ZooImage copyright
Tom Uhlman

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Ipuh at the Cincinnati Zoo

Scientists have decoded the genome of the Sumatran rhinoceros – one of the most threatened mammals on Earth.

Its genetic blueprint shows that populations have been in decline for a very long time.

The rhino’s troubles began during the last Ice Age, when its habitat shrunk, says a US team.

Since then, human pressures have caused numbers to dwindle further. There are now thought to be fewer than 250 individuals left in the wild.

“This species has been well on its way to extinction for a very long time,” said study researcher, Terri Roth at the Center for Conservation and Research of Endangered Wildlife at the Cincinnati Zoo and Botanical Garden.

The genome sequence data revealed the Pleistocene “was a roller-coaster ride for Sumatran rhinoceros populations,” added lead researcher, Dr Herman Mays of Marshall University in West Virginia.

The Pleistocene is the geological time period that lasted from about 2,588,000 to 11,700 years ago, spanning the world’s most recent Ice Age.

Genetic legacy

The researchers sequenced and analysed the first whole Sumatran rhino genome from a sample belonging to a well-known male at Cincinnati Zoo.

Ipuh lived at the zoo from the 1990s, but died four years ago at the age of 33. He sired three offspring, more than any other Sumatran rhino in the world, and deposited his genetic material in a gene bank.

Image copyright
Tom Uhlman

Image caption

Ipuh sired several rhino offspring

From his DNA, scientists were able to model the population history of the Sumatran rhino.

They say the population approached 60,000 individuals about 950,000 years ago.

By about 12,000 years ago – the end of the Pleistocene – Sumatran rhinos had lost much of their suitable habitat, like many other large mammals.

Land bridges exposed during the Ice Age connecting the islands of Borneo, Java, and Sumatra to the Malay Peninsula and mainland Asia had disappeared into the sea.

By 9,000 years ago, numbers had declined dramatically due to climate pressures.

“Their population bottomed out and never showed signs of recovery,” said Prof Mays.

“The Sumatran rhinoceros species is hanging on by a thread,” Dr Roth added. “We need to do more to save it.”

Human hunting

The Sumatran rhino once roamed from the foothills of the Himalayas in Bhutan and north-eastern India, through southern China, Myanmar, Thailand, Cambodia, Laos, Vietnam and the Malay Peninsula, and onto the islands of Sumatra and Borneo in Indonesia.

The species is now confined mainly to Sumatra and is listed as Critically Endangered by the International Union for the Conservation of Nature (IUCN).

The IUCN says over-hunting for its horn and other medicinal products has driven the animal to the brink of extinction.

There are over 20 Sumatran rhinos in captivity, mostly in Indonesia and Malaysia, with a few in the US.

Hundreds of large mammal species disappeared after the last Ice Age, due to climate change, loss of vegetation and human hunting.

Genetics gives researchers a window into the past; from a single whole genome sequence, they are able to model how the size of a population has changed over time.

This is particularly useful for ancient DNA or in very rare animal populations; it has been used to study the giant panda, passenger pigeon and the woolly mammoth.

Follow Helen on Twitter.

Article source: http://www.bbc.co.uk/news/science-environment-42352256

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Sea reptile fossil gives clues to life in ancient oceans

Fossil skeletonImage copyright
Yasuhisa Nakajima

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Paleontologists Tanja Wintrich and Martin Sander examine the fossil

A new fossil is shedding light on the murky past of the sea reptiles that swam at the time of the dinosaurs.

With tiny heads on long necks and four pointed flippers, plesiosaurs have been likened to Scotland’s mythical Loch Ness monster.

The German discovery proves that these sea creatures were alive more than 200 million years ago during the Triassic.

The fossilised bones give clues to how the animal survived a mass extinction that wiped out most living things.

”We now have the proof that this extremely successful group of marine reptiles already existed during Triassic times,” said paleontologist Martin Sander of the University of Bonn, who examined the fossil with colleague, Tanja Wintrich.

”This had been suspected for over 150 years, but it took a surprisingly long time for the hard evidence to emerge. ”

Long reign

The plesiosaur has been named Rhaeticosaurus mertensi.

Growth marks in its bones suggest the sea creature was a juvenile, grew very quickly and was warm-blooded.

Image copyright
Georg Oleschinski

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The skeleton is 237cm long

By being warm-blooded, plesiosaurs were able to roam the open seas in late Triassic times.

”Warm-bloodedness probably was the key to both their long reign and their survival of a major crisis in the history of life, the extinction events at the end of the Triassic,” said Prof Sander.

Plesiosaurs were not as hard hit by the extinction as shallow water and coastal animals. Their fossils have been found all over the world in Cretaceous and Jurassic rocks.

”What is also interesting is the location of the find in Germany, in Europe,” said Prof Sander.

”Three hundred years ago, the first plesiosaurs were found in England and the Continent, and now we have come full circle.”

The scientists found the skeleton buried in a clay pit owned by a German brick company near the village of Bonenburg.

The creature had a very stiff neck, which probably prevented it from twisting its head from front-to-back or side-to-side.

The research is published in the journal, Science Advances.

”’Triassic plesiosaur remains are few and far between, so the discovery of Rhaeticosaurus mertensi is really important in helping to understand what early plesiosaurs looked like,” said Dean Lomax of the University of Manchester, who was not connected with the study.

”’This will also provide new information about the early evolution of the group.”

Image copyright
Martin Sander

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The fossil was unearthed in a clay pit owned by a brick company

Plesiosaurs ruled the oceans for more than a hundred million years before dying out at the same time as the dinosaurs.

Despite their dominance of the prehistoric oceans, there are still many unanswered questions about their biology, anatomy and evolution.

Follow Helen on Twitter.

Article source: http://www.bbc.co.uk/news/science-environment-42339936

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Hurricane Harvey rainfall ‘weighed 127bn tonnes’

Media captionRoads turned to rivers across Houston as Harvey hit

Scientists have weighed the water that fell on Texas during the record-breaking Hurricane Harvey in August.

They calculate, by measuring how much the Earth was compressed, that the Category 4 storm dropped 127 billion tonnes, or 34 trillion US gallons.

“One person asked me how many stadia is that. It’s 26,000 New Orleans Superdomes,” said Adrian Borsa from the Scripps Institution of Oceanography.

His numbers were released as other scientists stated that this year’s big hurricanes had a clear human influence.

Harvey, Irma and Maria ripped through the US Gulf states and the Caribbean, leading to widespread flooding and wind damage.

Researchers told the annual meeting of the American Geophysical Union here in New Orleans that the heavy rainfall seen in Harvey was very likely exacerbated by the extra warming associated with increased greenhouse gases in the atmosphere.

Sea surface temperatures were particularly high in the Atlantic and the Gulf of Mexico this hurricane season. Warm ocean water acts as a fuel for the storms.

Media captionThe BBC’s James Cook found a scene of devastation in Rockport

Harvey devastated parts of the Texas coastline because it stalled, concentrating its deluge in a very narrow region. It was one of the heaviest precipitation events in recorded hurricane history.

Standard rain gauges saw upwards of 1,270mm (50 inches) of precipitation in places. But these were point measurements and Dr Borsa attempted to get a much broader view by assessing how much the Earth moved in response to the weight of overlying water.

This was detected by a network of high-precision GPS stations, which registered the vertical displacement of the land. “It’s like you sitting down on a mattress – it depresses; you stand up and it rebounds. The Earth behaves very similarly, like a rubber block.

“So the Earth is recording the effects of the loads acting on its surface.”

The GPS network is dense enough that a very wide picture of activity can be discerned. “It gives us a holistic view, not just point measurements,” Dr Borsa told BBC News.

What is especially smart is that the system can see the immediate change after the storm as water runs off the land through rivers, but also captures the much slower effect of water removal through evaporation, driven by the warmth of the Sun. This takes several weeks.

Interactive

See how West Houston Airport was flooded

After

West Houston Airport after the storm

Before

West Houston Airport before the storm

Interactive

See how Buffalo Bayou and Allen Parkway underpass flooded

After

Aerial images show how central Houston underpasses remain flooded, 30 August

Before

Satellite images shows central Houston

“One of the big deficiencies in our models is that evapotranspiration – that’s the Sun and plants doing their things – is not currently directly observed, and it’s half of the total water budget. I think GPS is going to be able to provide very useful information about this.”

At the same AGU gathering, the American Meteorological Association revealed that its annual report on extreme weather events had identified three that would “not have been possible” without the influence of human-induced climate change.

These were: the record-breaking global temperatures in 2016; the 2016 heat wave across Asia and the high ocean temperatures measured off the coast of Alaska.

These were events that happened because “we have created a new climate,” said National Oceanographic and Atmospheric Administration (Noaa) climate scientist Stephanie Herring.

The report also concluded that other heat waves around the world were made more intense by climate change and that Arctic warming was “most likely” not possible without it.

The coral bleaching event in the Great Barrier Reef and other marine ecosystems in the Pacific Ocean were also amplified by “human-caused warming of the ocean”.

The research is primarily based on comparing models, or simulations, of our climate. “We run a model that shows what the world looks like today and we can validate those models against what is actually happening,” explained Dr Herring.

“Then we compare it to a model of an ‘alternative world’ in which – theoretically – climate change never happened; as if humans didn’t emit greenhouse gases since the industrial revolution.

“So we can look at a world with climate change and a world without it.”

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Harvey’s rain could have filled 26,000 New Orleans Superdomes

Article source: http://www.bbc.co.uk/news/science-environment-42347510

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How Greenland would look without its ice sheet

Media captionThe map reveals a hidden world of mountains and canyons

Scientists have produced a stunning visualisation of Greenland – without its ice cover.

It is made from decades of survey data that show the position and shape of the territory’s bedrock, and the surrounding seafloor.

This is critical information needed to understand how the huge island might respond to a warming world.

Were all the ice on Greenland to melt, it would raise global sea-levels by 7.42m (24.34ft).

This is one of the refined statistics to come out of the new compilation of data. It is a simple calculation: if you know the elevation of the top of the ice sheet and you subtract from that the height of the bedrock – you get a volume: 2.9 million cubic km.

The 7.42m figure is seven cm more than previous estimates.

“[It's] a little bit more than we thought, but not a whole lot more,” explained Dr Mathieu Morlighem from the University of California at Irvine, US.

“And the reason for that is that although we do find deeper fjords and deeper valleys, they’re very narrow and constrained along the sides of the ice sheet. The interior hasn’t change a lot, however.”

Greenland ice sheet by the numbers

Media captionMathieu Morlighem: “Just seeing the detail the map has is absolutely beautiful”
  • Total ice area: 1.799 million sq km
  • Total ice volume: 2.99 million cu km
  • Mean thickness: 1,673m
  • Thickest ice: 3,488m

For comparison, the Antarctic ice sheet has a volume of 26.5 million cu km

Greenland is currently losing about 260 billion tonnes of ice to the ocean every year. It sounds a lot – and it is, but no-one is expecting an immediate collapse – not for centuries, at least.

Nonetheless, some of the answers as to how fast changes may come will be in this map’s data.

“If you’re trying to model an ice sheet, the single most important input is ice thickness,” said Prof Jonathan Bamber. “Why’s that? Because velocity is proportional to the fourth power of thickness. So differences in thickness make for huge differences in the velocity of the ice in our models; and to things like thermodynamics, because thick ice is warmer than thin ice, and so on,” the Bristol University, UK, glaciologist told BBC News.

The colourful map is being distributed here at the Fall Meeting of the American Geophysical Union (AGU), the largest annual gathering of Earth and planetary scientists.

Image copyright
M.Jakobsson

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Ice drains from Greenland down deep narrow fjords

It is a dramatic rendering of an initiative called BedMachine which has sought to pull together everything we know about what lies under and around the giant ice sheet.

Image copyright
PAUL ANKER

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Kelly Hogan: Ice loss at Petermann is mostly from warm water incursion

Scientists working on this project published a summary of their findings in a paper in Geophysical Research Letters last month, and now the British Antarctic Survey’s (BAS) mapping department, at the request of Prof Bamber, has put the data in a visually understandable form.

Interesting features to peruse include the channelled terrain feeding the mighty Jakobshavn Glacier in the west.

Jakobshavn spews countless icebergs into the North Atlantic, and is responsible for draining 6.5% of the ice sheet.

Look at the spine of Greenland and you will see the mega-canyon that runs northwards towards another of the territory’s big iceberg exporters – Petermann Glacier.

In studying the hidden landscape, scientists are now pretty confident that both ice streams sit on top of valley systems that were cut by rivers that flowed across Greenland long before there was an ice sheet. And it is clear also that meltwater continues to run down these valleys, under the glaciers, lubricating their flow.

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  • New map traces Shackleton’s footsteps
  • Giant iceberg splits from Antarctic
  • ‘Upside-down ice canyon’ revealed

Media captionGreenland’s mega-canyon was originally cut by an ancient river system

The data for the map comes from three principal sources – from airborne radar that is able to penetrate the ice sheet to see the shape of the bed below; from ships surveying offshore, using sonar to map sea-bottom depths; and then there is a degree of modelling in some of the hard-to-reach places in fjords, explains BAS map-maker Dr Peter Fretwell.

“Around the coast it can be very difficult to get radio echo soundings (radar) because the surface is often crevassed and the radio waves won’t penetrate through that. So in some fjords and bays, modelling is used, based on the speed of the glaciers. From their speed, you can estimate their thickness,” he said.

Wherever possible, though, scientists have endeavoured to get up the fjords to acquire direct data.

This has been the imperative of the US-led OMG (Oceans Melting Greenland) project that is surveying large sections of the coastline.

OMG is finding that many of the glaciers terminating in fjords are so thick they are at risk of melting from the intrusion of warm ocean water at depth.

Image copyright
Bjorn Eriksson

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Great efforts are being made to get into fjords to map their shape

Dr Kelly Hogan, a BAS co-author on the BedMachine paper, found a similar picture when she joined an expedition to study Petermann.

“Most of the losses for Petermann Glacier, for sure, about 80%, are the result of warm ocean water getting under the glacier and melting it from below – not from iceberg calving,” she said. “But if you get increased melting from below, you can get big channels forming on the underside of the floating front of the glacier and this can lead to thinning and fracturing that then make the glacier potentially more predisposed to breaking up.”

Prof Bamber cautions, however, that there is a lot of complexity bound up in the new map.

Some of the mouths to the deep fjords, he says, have tall ridges, or sills, that act as barriers to the invasion of warm bottom-water.

“What we’re starting to understand is that adjacent marine-terminating glaciers that are experiencing the same changes in forcing – in other words, the same changes in the ocean – can respond in very different ways, depending on the geometry of the fjord in which they lie.

“So, the better we can constrain these geometries, the better we will be able to model the interaction between the ice sheet and the ocean. At AGU, there are lots of sessions on this interaction. It’s kind of the big thing at the moment,” the Bristol scientist told BBC News.

Article source: http://www.bbc.co.uk/news/science-environment-42260580

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Jupiter Great Red Spot has deep roots

Media captionA visualisation shows what it would be like to dive into Jupiter’s atmosphere.

Scientists are beginning to unlock the secrets of the Great Red Spot on Jupiter – the biggest storm in the solar system.

This spectacular anticyclone has been in existence for more than 150 years. It is wider than the Earth.

One of the big puzzles has concerned its roots and how deep they go.

Now, the American space agency’s Juno probe at Jupiter has an answer. The storm system extends down at least 350km (200 miles) into the atmosphere.

And the roots could well run deeper still.

The 350km is just the limit of what Juno’s microwave radiometer can sense.

This instrument tracks the warmth (hundreds of degrees Celsius) in the atmosphere associated with the storm.

But if Juno can make some gravity measurements over the region as well, it might also detect mass movements connected with the spot down at over 1,000km below the planet’s cloud tops.

Image copyright
NASA

Image caption

Juno passed directly over the Great Red Spot back in July

“We’re now putting together the 3D structure of the Great Red Spot, whereas we’ve only known it from a 2D perspective before,” said Prof Andrew Ingersoll, from the California Institute of Technology.

“Precisely how deep the roots go is still to be determined. But the warmth we see at depth is consistent with the winds we measure at the top of the atmosphere.”

Those winds move at more than 120m/second – getting on for 300mph. That is far faster than anything generally seen on Earth, including its high-altitude jet stream.

  • Behold Jupiter’s Great Red Spot
  • Juno peers below Jupiter’s clouds
  • Nasa probe arrives in Jupiter orbit

Media captionAndrew Ingersoll: “One explanation for what keeps the Spot going is cannibalism “

Prof Ingersoll was speaking at the Fall Meeting of the American Geophysical Union (AGU) – the world’s largest annual gathering of Earth and planetary scientists.

He said the Juno team wanted to understand the key mechanisms that drove the spot and kept it from dissipating.

But the data gathered on the red spot was simply not compatible with models used to study Earth’s weather.

“For practical reasons, the first efforts to understand the red spot and all the flows on Jupiter borrowed computer models from Earth science,” he said. But for this gigantic storm “we’ve got to stretch the models more than that”.

Image copyright
NASA/JPL-Caltech/SwRI/MSSS/G.Eichstadt/J.Cowart

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One of the delights of the mission has been the way citizen scientists have interpreted its images

The team has produced a stunning visualisation of the latest data. The little film takes the viewer on a flyover of the cloud tops before a plunge into and through the heat of the spot itself.

The Juno probe arrived at the fifth planet from the Sun on 4 July last year. Since then, it has been making a close pass over the gas giant every 53 days. Its seven scientific instruments are endeavouring to reveal Jupiter’s inner workings.

The mission hopes to better explain the planet’s origins.

Its great size means it was almost certainly the first object to form in the solar system after the Sun. And that means its influence on everything around it has been immense.

It is impossible, says the mission team, to understand the other planets without first thoroughly knowing Jupiter.


  • Jupiter is 11 times wider than Earth and 300 times more massive
  • It takes 12 Earth years to orbit the Sun; a “day” is 10 hours long
  • In composition, it resembles a star; it’s mostly hydrogen and helium
  • Under pressure, the hydrogen assumes a state similar to a metal
  • This “metallic hydrogen” could be the source of the magnetic field
  • Most of the visible cloud tops contain ammonia and hydrogen sulphide
  • Jupiter’s low-latitude “bands” play host to very strong east-west winds
  • The Great Red Spot is a giant storm vortex wider than planet Earth

Article source: http://www.bbc.co.uk/news/science-environment-42319405

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Nasa’s New Horizons probe strikes distant gold

The moonlet may be about 200-300km from the main objectImage copyright
NASA

Image caption

Artwork: The moonlet may be about 200-300km from the main object

The American space agency’s New Horizons mission has struck gold again.

After its astonishing flyby of Pluto in 2015, scientists have just discovered that the probe’s next target is not one object but very likely two.

Earth-based observations suggest the small icy world, referred to simply as MU69, has a moonlet.

It seems New Horizons will now be making a two-for-the price-of-one flyby when it has its encounter on New Year’s Eve and New Year’s Day, 2019.

The plan is for the spacecraft to pass the 30-40km-wide main object with a separation of just 3,500km, acquiring high-resolution pictures and other data.

This should reveal new information on the Kuiper Belt – the band of distant, frozen material that orbits far from the Sun. On flyby day, New Horizons and MU69 will be some 6.5 billion km (4.5 billion miles) from Earth.

“Besides being the farthest exploration in the history of humankind, this flyby is also going to the most primitive and pristine object ever explored,” said Prof Alan Stern, the principal investigator on New Horizons.

“We’ve really never been to anything like this. Of course, we’ve had lots of missions to comets that come from the Kuiper Belt, but they’ve come down into the inner Solar System where they’re processed, sometimes through hundreds of passages by the Sun, and they’re much smaller.

“If you remember Rosetta’s comet, 67P, which you saw so many pictures of from that great Esa/Nasa mission – this is a much larger target. It could fit about a thousand Rosetta comets inside itself.”

Prof Stern was giving an update on preparations for the MU69 encounter here at the Fall Meeting of the American Geophysical Union.

Image caption

Scientists have considered the possible shapes of the main MU69 object

His team described efforts earlier this year to tie down details about the target object’s precise movement and size using occultation.

This involves making observations of MU69 as it passes in front of a far-off star.

The tell-tale details are in the way the star blinks.

What emerged from the studies was fascinating. Not only does it seem there is an accompanying moonlet perhaps 200-300km from MU69, but the main target itself may also actually be a double act – either two individual units with a small gap between them; or just touching, something called a contact binary.

“This is very exciting. This is going to have a lot of surprises,” said New Horizons science team-member Dr Marc Buie, of the Southwest Research Institute, Boulder, Colorado.

“We think this is probably a sign that the object itself was not a collision fragment; we think it was made this way. And so we really are going to see something that dates back to the birth of our Solar System.”

Media captionAfter seeing Pluto disappear in the rearview mirror, Alan Stern looks towards MU69

The flyby campaign begins in earnest in August, when the first course corrections that may be required for New Horizons will be made.

Observations will also take place to ensure there are no hazards in the vicinity of MU69 that might necessitate a wider pass.

The serious business of the flyby occurs over a nine-day period starting on 25 December, 2018.

New Horizons will focus on the Kuiper Belt object, hoping to return images that have a best resolution of about 30m per pixel.

The first of these should come back to Earth a couple of days after closest approach, which currently is timed to occur at 05:33 GMT on 1 January, 2019.

“Using New Horizons’ suite of seven instruments, we’ll be characterising the geology and morphology of the surface, looking to see whether there are any craters. We certainly expect to see craters,” explained team member Dr Anne Verbiscer from the University of Virginia.

“Possibly there could be grooves. We’ll also map the surface composition, searching for possible ices as we saw on Pluto.

“We also want to know what makes MU69 so dark and red. And we’ll be searching for satellites and rings and asking if that moon is really there; and are there any others?”

Follow Jonathan on Twitter

Article source: http://www.bbc.co.uk/news/science-environment-42333783

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Warmer Arctic is the ‘new normal’

Media captionSea ice that is more than four years old has largely disappeared in the Arctic

A warming, rapidly changing Arctic is the “new normal” and shows no signs of returning to the reliably frozen region of the past.

This is according to the US National Oceanic and Atmospheric Administration’s Arctic Report Card.

Director of the administration’s Arctic Researcher Program, Dr Jeremy Mathis, said the region did a great service to the planet – acting as a refrigerator.

“We’ve now left that refrigerator door open,” he added.

Dr Mathis was speaking at the annual American Geophysical Union meeting in New Orleans, where Noaa presented its annual summation of Arctic science.

  • Starving polar bear: The ‘face of climate change’?

This is the 12th report the administration has produced. And although it pointed to “a few anomalies” in a recent pattern of warming in the Arctic region, Dr Mathis said: “We can confirm, it will not stay in its reliably frozen state.”

“The thing I took that had the most resonance for me was we’re able to use some really long-term records to put the Arctic change into context – going back more than 1,500 years.

“What’s really alarming for me is that we’re seeing the Arctic is changing faster than at any rate in recorded history.”

The speed of change, Dr Mathis added, was making it very hard for people to adapt.

“Villages are being washed away, particularly in the North American Arctic – creating some of the first climate refugees,” he said.

“And pace of sea level rise is increasing because the Arctic is warming faster than we anticipated even a decade ago.”

The 2017 Arctic headlines

Media captionWhich cities might flood as the ice melts?
  • Warmer air: Average annual air temperature over land was the second highest after 2016, with a temperature 1.6C above average.
  • Declining sea ice: The maximum winter sea-ice area, measured each March, was the lowest ever observed. Sea ice is also getting thinner each year.
  • Warmer ocean: Sea surface temperatures in August 2017 were 4C above the average in the Barents and Chukchi seas. Surface waters of the Chukchi Sea have warmed by more than half a degree C per decade since 1982.
  • Plankton blooms: Springtime melting and retreating sea ice allows sunlight to reach the upper layers of the ocean, meaning more of these microscopic marine plants can photosynthesise.
  • Greener tundra: Overall vegetation, including plants getting bigger and leafier and shrubs and trees taking over. Grassland or tundra, increased across the Arctic in 2015 and 2016, as measured by satellite.
  • Ups and downs for snow: For the 11th year in the past 12, snow cover in the North American Arctic was below average, with communities experiencing earlier snow melt. The Eurasian part of the Arctic saw above average snow cover extent in 2017 – the first time that has happened since 2005.
  • Less melt on Greenland Ice Sheet: Melting began early on the Greenland Ice Sheet in 2017, but slowed during a cooler summer, resulting in below-average melting when compared with the previous nine years. Overall, the Greenland Ice Sheet, a major contributor to sea-level rise, continued to lose mass this past year, as it has since 2002 when measurements began.

Source: 2017 NOAA Arctic Report Card

Scientists say it is clear that human-induced climate change is contributing to making the Arctic a warmer and more dynamic place.

“When we look at the darkening of the Arctic,” said Dr Mathis, “reflective, icy surfaces are melting to reveal darker surfaces that absorb more of the Sun’s energy.

Image copyright
NOAA

Image caption

Greening Arctic: Vegetation in the tundra is becoming ‘bigger and leafier’

“So it probably only took a little bit of human-induced change to start the Arctic down this cascading pathway; a little bit of ice melting led to a little bit of warming, which led to more ice melting, which led to more warming.

“And now we’re seeing an acceleration – a runaway effect that may eventually be a catastrophic runaway effect starting to take hold in the Arctic.”

Oceanographer and retired US Navy Rear Admiral Timothy Gallaudet, who was appointed by the Trump Administration as acting administrator of Noaa, was asked during the Arctic report presentation about the response of the White House to the findings.

Many scientists viewed President Trump’s recent decision to withdraw the US from the Paris Climate Agreement as clear evidence of his scepticism about human-induced climate change.

He said that the White House was “addressing and acknowledging it and factoring it in to their agenda”.

Dr Mathis added that information coming from this report was “beyond reproach”.

“They’re facts. Facts weighted in thousands and thousands of scientific measurements that have been validated and peer reviewed by a community of experts working in the area for decades.

“Policy-makers can use those facts as they see fit.”

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Article source: http://www.bbc.co.uk/news/science-environment-42330771

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‘Worrying alarm call’ for world’s birds on brink of extinction

Black-legged kittiwakeImage copyright
Ed Marshall

Image caption

Black-legged kittiwake: Colonies are struggling to feed their chicks

Overfishing and changing sea temperatures are pushing seabirds to the brink of extinction, according to new data on the world’s birds.

Birds that are now globally threatened include the kittiwake and the Atlantic puffin, which breed on UK sea cliffs.

Meanwhile, on land, the Snowy Owl is struggling to find prey as ice melts in the North American Arctic, say conservation groups.

The iconic bird is listed as vulnerable to extinction for the first time.

“Birds are well-studied and great indicators of the health of the wider environment,” said Dr Ian Burfield, global science coordinator at BirdLife International, the IUCN Red List authority on birds.

”A species at higher risk of extinction is a worrying alarm call that action needs to be taken now. ”

He added that success in kiwi and pelican conservation had shown that, when well-resourced and supported, conservation efforts do pay off.

Image copyright
Francais Cadien

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Snowy owl: Threatened by shortage of key prey

Worldwide, over a quarter of more than 200 bird species reassessed by the International Union for the Conservation of Nature have been moved to higher threat categories while a similar number have been downgraded.

Fishing pressures

Seabirds are of particular concern, including Cape gannets, which are now classified as Endangered, and the Antipodean Albatross, which risks being drowned by fishing lines.

Fishing pressures and ocean changes caused by climate change are reducing food supply for the chicks of seabirds, while adults receive little protection when they fly over areas of the ”high seas” that do not fall under the jurisdiction of any country, says BirdLife International.

The kittiwake (Rissa Tridactyla, or black-legged kittiwake), which breeds along northern coasts, has declined globally by about 40% since the 1970s.

Image copyright
Kath Walker

Image caption

Antipodean albatross: Bycatch in longline fishing is a major threat

More than 70% of the British breeding kittiwake population is found in Scotland.

However, there has been a dramatic decline, particularly in Orkney and Shetland and on St Kilda in the Western Isles.

“Some efforts are underway to protect important seabird foraging areas in international waters, but there is much more we could do around the UK to protect our internationally important and increasingly threatened seabird populations,” said Laura Bambini, the RSPB Scotland’s seabird recovery officer.

Sandeels are a vital food source for breeding seabirds in the North Sea. The eels are threatened by rising sea temperatures and are also harvested by commercial fisheries.

“We need to ensure that the future management of the sandeel fishery is sustainable,” said Dr Euan Dunn, the RSPB’s marine policy specialist.

Image copyright
John Paterson

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Cape gannet: Fish stocks are depleted, so it is going hungry

The other birds found in the UK to be placed on the IUCN Red List are:

  • Atlantic Puffin
  • European Turtle Dove
  • Pochard
  • Slavonian Grebe
  • Balearic Shearwater
  • Long-tailed Duck
  • Velvet Scoter
  • Aquatic Warbler.

Flagship species

Elsewhere, the Snowy Owl has moved up the rankings from Least Concern to Vulnerable. The North American population has declined by 64% since 1970, as changing temperatures affect its habitat and prey. Collisions with vehicles and utility lines are also a threat to the owl, made famous in the Harry Potter books.

“Arctic biodiversity is under pressure from a number of stressors, including climate change, so hopefully the uplisting of the Snowy Owl as a flagship species will also draw attention to wider issues in this region,” said Dr Burfield.

Image copyright
A Vizi

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Dalmatian pelican: On the rise due to added protection measures

In Asia, the Yellow-breasted Bunting (Emberiza aureola), which is illegally trapped for food, has been uplisted from Endangered to Critically Endangered.

More positive news comes from Europe, where Dalmatian Pelicans are recovering after conservation efforts. This year, pelicans on Lake Skadar in Montenegro had their most successful breeding season ever, raising 60 chicks.

However, while two species of kiwi in New Zealand are now less threatened, the Kea is declining, in part due to tourists feeding the parrots with junk food like bread and chips.

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Article source: http://www.bbc.co.uk/news/science-environment-42314289

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