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Genomes document ancient mass migration to Europe

Genomes document ancient mass migration to Europe
From the BBC

ancient skeleton

Nomadic herders moved en masse into Europe from the steppe around 4,500 years ago

DNA analysis has revealed evidence for a massive migration into the heartland of Europe 4,500 years ago.

Data from the genomes of 69 ancient individuals suggest that herders moved en masse from the continent’s eastern periphery into Central Europe.

These migrants may be responsible for the expansion of Indo-European languages, which make up the majority of spoken tongues in Europe today.

An international team has published the research in the journal Nature.

Prof David Reich and colleagues extracted DNA from remains found at archaeological sites around the continent. They used a new DNA-enrichment technique that greatly reduces the amount of sequencing needed to obtain genome-wide data.

Their analyses show that 7,000-8,000 years ago, a closely related group of early farmers moved into Europe from the Near East, confirming the findings of previous studies.

The farmers were distinct from the indigenous hunter-gatherers they encountered as they spread around the continent. Eventually, the two groups mixed, so that by 5,000-6,000 years ago, the farmers’ genetic signature had become melded with that of the indigenous Europeans.

But previous studies show that a two-way amalgam of farmers and hunters is not sufficient to capture the genetic complexity of modern Europeans. A third ancestral group must have been added to the melting pot more recently.

Prof Reich and colleagues have now identified a likely source area for this later diaspora. The Bronze Age Yamnaya pastoralists of southern Russia are a good fit for the missing third genetic component in Europeans.

The team analysed nine genomes from individuals belonging to this nomadic group, which buried their dead in mounds known as kurgans.

The scientists contend that a group similar to the Yamnaya moved into the European heartland after the invention of wheeled vehicles, contributing up to 50% of ancestry in some modern north Europeans. Southern Europeans on the whole appear to have been less affected by the expansion.

By 5,000-6,000 years ago, Europeans were a two-way mix of indigenous hunters and Near Eastern farmers

Even more intriguing is the possible link between this steppe expansion and the origins of Indo-European languages.

Most indigenous European tongues, from English to Russian and Spanish to Greek, belong to the Indo-European group. The classification is based on shared features of vocabulary and grammar.

Basque, spoken in south-west France and northern Spain, does not fit in this group, and may be the only surviving relic of an earlier group of languages once spoken more widely.

Two principal hypotheses have been put forward to explain the preponderance of Indo-European tongues in Europe today.

According to the “Anatolian hypothesis”, Indo-European languages were spread by the first farmers from the Near East 7,000-8,000 years ago.

But the latest paper supports the “Steppe hypothesis”, which proposes that early Indo-European speakers were Bronze Age farmers on the grasslands north of the Black and Caspian Seas.

“An open question for us is whether the languages spoken by these steppe migrants were just ancestral to a sub-set of Indo-European languages in Europe today – for example, Balti-Slavic and maybe Germanic – or the great majority of Indo-European languages spoken in Europe today,” Prof Reich told BBC News.

But he added that Indo-European languages spoken in Iran and India had probably already diverged from those spoken by the Yamnaya before the nomads blazed a trail into Europe.


Bright spotlight on Dawn mission to Ceres

Bright spotlight on Dawn mission to Ceres
By Jonathan Amos
BBC Science Correspondent

The bright spots inside a 92km-wide crater have been the big surprise of the encounter so far

Scientists say they are hugely excited to learn the origin of two bright spots on the surface of Ceres.

The US space agency’s Dawn probe is bearing down on the dwarf planet and on Friday will be captured by its gravity.

That will allow the satellite to spiral down in altitude in the coming months, to take ever sharper images of the spots, which sit inside a wide crater.

The striking features could be where an impact has dug out surface deposits and exposed the dwarf’s interior layers.

But deputy project scientist Dr Carol Raymond cautioned that the resolution of Dawn’s imagery was not good enough at the moment to make any definitive statements.

“These spots were extremely surprising and they have been puzzling to everyone who has seen them,” the Nasa Jet Propulsion Laboratory researcher told reporters.

“They show up in a 92km-wide crater that’s about 19 degrees North latitude. The spot in the centre is about twice as bright as the spot on the side of the crater, and as yet it has not been resolved, meaning it is smaller than the 4km pixel size [of the images].

“But its apparent brightness is already off-scale; it’s consistent with high reflective materials.”

Intriguingly, the European Space Agency’s Herschel telescope reported last year seeing water vapour coming from two sectors on Ceres. One of these sectors includes the location of the spots. That could be very significant, Dr Raymond said.

“The association with the impact crater may indicate that impact heating resulted in exposure of underlying ice [and] its vaporisation; and perhaps we’re seeing a deposit left behind which is rich in material like salts.”

Dawn will spend 14 months studying the 950km-diameter dwarf planet, which is the largest object in the asteroid belt between Mars and Jupiter.

NASA

An artist’s impression of Dawn firing its ion engine on approach to Ceres

The satellite has turned up at Ceres having previously visited the asteroid Vesta. This 530km-wide rock had the look of a punctured football, the result of a colossal collision sometime in its past that ripped a big chunk out of its southern polar region.

Ceres, on the other hand, is big enough for gravity to have pulled it into a more spherical shape.

Scientists think both bodies are fledglings that never quite made it to the planetary big time.

In the case of Vesta, it underwent a lot of the same processes that transformed the early Earth, such as differentiating its insides to include an iron core.

In contrast, Ceres’s bid to reach the major planet league probably stalled quite quickly.

Researchers believe its interior is dominated by a rocky core topped by ice that is then insulated by rocky lag deposits at the surface.

The surface of Ceres is covered with craters of many shapes and sizes

A big question the mission hopes to answer is whether there is a liquid ocean of water at depth. Some models suggest there could well be.

The evidence may well be found in Ceres’ craters which have a very muted look about them. That is, the soft interior of the dwarf has undoubtedly had the effect of relaxing their original hard outline.

“One of the prime motivations of the Dawn mission is to examine these building blocks of the planets, Vesta and Ceres, which are two intact proto-planets from the very dawn of the Solar System. They’re literally fossils that we can investigate to really understand the processes that were going on at that time,” Dr Raymond said.

At capture, the satellite will be at a separation of about 40,000km. Controllers at Earth will work in the next few weeks to reshape the orbit to get it ready for science.

One issue is that Dawn approached the dwarf from its Sun-lit side. The probe has now gone over to the dark side, and it will not come back around again to take images until late April.

But then onwards, the pictures will just get better and better as the orbit is progressively lowered.

“We’ll get to our final orbit in December of this year at just [380km] from the surface, which for context is just a little bit lower than the International Space Station orbits around the Earth. From this vantage point, Dawn will acquire its highest detail and highest resolution images of the surface,” said Nasa project manager Robert Mase.

Discovered in 1801 by the Sicilian astronomer Father Giuseppe Piazzi, Ceres is named after the Roman goddess of agriculture and harvests.

Craters on Ceres will follow a similar theme and will be named after gods and goddesses of agriculture and vegetation from mythology. Other features on the dwarf will be named after agricultural festivals.

Ceres

The soft outline of the big basin suggests that the surface has relaxed over time


Shocking or intriguing NASA challenges physics to build faster than light spaceship warp drive

 

Shocking or intriguing NASA challenges physics to build faster than light spaceship warp drive

by Vandita from We Are Anonymous anahq.com

Startrek

Starship

NASA scientist Harold White has stunned the world with his announcement that he and his team has begun work on the development of a faster-than-light Warp Drive spaceship that can move faster than the speed of light defying Albert Einstein’s Theory of Special Relativity. Warp Drive, which is all set to challenge the light speed barrier, could result in speeds that could take a spacecraft to Alpha Centauri in a only two weeks even though the system is 4.3 light-years away! The idea sounds fascinating but disobeys the laws of physics.

In his 1994 paper titled The Warp Drive: Hyper-Fast Travel Within General Relativity physicist Miguel Alcubierre had suggested a mechanism by which space-time could be “warped” both in front of and behind a spacecraft. The idea immediately caught White’s attention.

“Remember, nothing locally exceeds the speed of light, but space can expand and contract at any speed. However, space-time is really stiff, so to create the expansion and contraction effect in a useful manner in order for us to reach interstellar destinations in reasonable time periods would require a lot of energy,” White told io9.

Warp Drive

Alcubierre Warp Drive

The Theory of Special Relativity does not allow objects to move faster than the speed of light within space-time. To increase the speed of moving objects to match the speed of light, it would need infinite amount of energy. White in a way suggested horrific amounts of energy —equal to the mass-energy of planet Jupiter (which is 1.9 × 1027 kilograms or 317 Earth masses). As a result, the idea was brushed aside as being far too impractical.

White later collaborated with Mark Rademaker, an artist, to create a new, more realistic design of what such a ship might actually look like. The updated model is more compact and chunkier and includes a sleek ship nestled at the center of two massive rings of negative energy which will create the warp bubble.

Mark Rademaker’s design of what such a ship might actually look like.

At the 100 Year Starship Conference in Atlanta, he said that the Warp Drive could be powered by a mass that’s even less than that of the Voyager 1 spacecraft. The reduction in mass from a Jupiter-sized planet to an object that weighs a mere 1,600 pounds completely reset White’s sense of plausibility — and NASA’s.

Warp Drive for FTL travel is at the level of speculation since NASA also considers that FTL travel is impossible. FTL results in time travel and time travel is considered far more impossible than light travel. Dr White too admits his research is still small-scale and is light years away from any type of engine that could be constructed into a spaceship like the USS Enterprise.

The story so far. Here are a number of clips from the BBC Explorations series that looks at what we have achieved so far in space travel.


Sources:

http://fossbytes.com/nasa-working-warp-drive-faster-than-light-spaceship/

http://io9.com/5963263/how-nasa-will-build-its-very-first-warp-drive

http://anonhq.com/shocking-or-intriguing-nasa-challenges-physics-to-build-faster-than-light-spaceship-warp-drive/

Alien star system buzzed the Sun

 

 

Alien star system buzzed the Sun
By Paul Rincon
Science editor, BBC News website

Scholz’s star – shown in this artist’s impression – is currently 20 light-years away. But it once came much closer

An alien star passed through our Solar System just 70,000 years ago, astronomers have discovered.

No other star is known to have approached this close to us.

An international team of researchers says it came five times closer than our current nearest neighbour – Proxima Centauri.

The object, a red dwarf known as Scholz’s star, cruised through the outer reaches of the Solar System – a region known as the Oort Cloud.

Scholz’s star was not alone; it was accompanied on its travels by an object known as a brown dwarf. These are essentially failed stars that lacked the necessary mass to get fusion going in their cores.

The findings are published in Astrophysical Journal Letters.

Observations of the dim star’s trajectory suggest that 70,000 years ago this cosmic infiltrator passed within 0.8 light years of the Sun. By comparison, Proxima Centauri is 4.2 light years away.

Close encounter
In the paper, astronomers led by Eric Mamajek at the University of Rochester, New York, say they are 98% certain that Scholz’s star travelled through what is known as the “outer Oort Cloud” – a region at the edge of the Solar System filled with trillions of comets a mile or more across.

This region is like a spherical shell around the Solar System and may extend out to as much as 100,000 Astronomical Units, or AU (one AU is the distance between the Earth and the Sun).

The Oort Cloud is thought to give rise to long-period comets that can swing past the Sun when their orbits are disturbed.

Alien

The Oort Cloud in perspective: 1 Astronomical Unit (AU) represents the distance from the Earth to the Sun

To determine the trajectory of the star, the researchers needed two pieces of information: the change in distance from the Sun to the star (its radial velocity) and the star’s motion across the sky (its tangential velocity).

Scholz’s star currently lies 20 light years away – making it a fairly nearby system. But it showed very slow tangential motion for a star this close. This indicated that it was either moving away from us or towards a future close encounter with the Solar System.

The radial velocity measurements confirmed that the binary star system was actually speeding away from us. By tracing its movements back in time, they found its close shave with the Sun occurred some 70,000 years ago.

Grand theft Oort-o?
A star passing through the Oort Cloud could potentially play gravitational havoc with the orbits of comets there, sending them on trajectories into the inner Solar System. But Dr Mamajek believes the effects of Scholz’s star on our cosmic neighbourhood were “negligible”.

“There are trillions of comets in the Oort cloud and likely some of them were perturbed by this object,” he told BBC News.

“But so far it seems unlikely that this star actually triggered a significant ‘comet shower’.”

The effect of a passing star on the Oort Cloud is a function of the star’s mass, speed and proximity. The worst case scenario for stirring up comets would be a slow-moving, massive star that came close to the Sun.

Scholz’s star came relatively close, but the binary system (the red dwarf and its brown dwarf companion) has a low mass and it was speeding by. These factors conspired to make its effect on the Oort Cloud very small.

While this is the closest flyby detected so far, Dr Mamajek thinks it’s not uncommon for alien stars to buzz the Sun. He says a star probably passes through the Oort Cloud every 100,000 years, or so.

But he suggests an approach as close – or closer – than that made by Scholz’s star is somewhat rarer. Dr Mamajek said mathematical simulations show such an event occurs on average about once every nine million years.

“So it is a bit of a strange coincidence that we happen to have caught one that passed so close within the past 100,000 years or so,” he said.


New Horizons probe eyes Pluto for historic encounter

By Jonathan Amos

Science correspondent, BBC News

When it gets to Pluto, the New Horizons probe will have a packed schedule of observations

A Nasa probe is to start photographing the icy world of Pluto, to prepare itself for a historic encounter in July.

The New Horizons spacecraft has travelled 5bn km (3bn miles) over nine years to get near the dwarf planet.

And with 200m km still to go, its images of Pluto will show only a speck of light against the stars.

But the data will be critical in helping to align the probe properly for what will be just a fleeting fly-by.

Pluto will be photographed repeatedly during the approach, to determine the probe’s position relative to the dwarf planet, explained Mark Holdridge, from the Johns Hopkins University’s Applied Physics Laboratory (JHUAPL) in Baltimore.

“We then perform a number of correction manoeuvres to realign our trajectory with the reference trajectory, thus ensuring we hit our aim point to travel through the Pluto system,” he said.

Any initial correction is likely to be made in March.

The Pluto system has five known moons. Others may be discovered in the coming months

When New Horizons arrives at Pluto it will be moving so fast – at almost 14km/s – that going into orbit around the distant world is impossible; it must barrel straight through instead.

One complication is that the seven different instruments aboard the spacecraft need to work at different distances to get their data, and so the team has constructed a very elaborate observation schedule for them all.

But what this means is that very precise timing will be required to make sure the flyby runs smoothly.

The closest approach to Pluto is set for around 11:50 GMT on 14 July – at a miss distance of roughly 13,695km from the surface.

Mission planners want the exact timings nailed to within 100 seconds. New Horizons will know then where and when to point the instruments.


Dwarf Planet Pluto – Demoted but undiminished

mysterious shape to be investigated

Synthetic view Hubble’s best is a synthetic composite of multiple views. What are those shapes?

  • Discovered by Clyde Tombaugh on 18 February 1930
  • It is named after the Roman god of the underworld
  • An average of 5.9bn km from Sun and orbits every 248 years
  • Measuring its diameter is difficult but roughly 2,300km
  • It has a thin nitrogen atmosphere that comes and goes

 


The Pluto mission is being billed as the last great encounter in planetary exploration.

For people who grew up with the idea that there were “nine planets”, this is the moment they get to complete the set.

Robotic probes have been to all the others, even the distant Uranus and Neptune. Pluto is the last of the “classical nine” to receive a visit.

Of course, this 2,300km-wide ice-covered rock was demoted in 2006 to the status of mere “dwarf planet”, but scientists say that should not dull our enthusiasm.

The dwarfs are the most numerous planetary class in the Solar System, and Nasa’s New Horizons probe is one of the first opportunities to study an example up close.

The first set of navigation pictures may not be anything special, but by May, the probe will be returning views of Pluto that are better than anything from Hubble. Come July, the view should be spectacular, said Andy Cheng, the principal investigator on the probe’s main camera, which is called LORRI.

As Rebecca Morelle reports, even the Hubble Space Telescope could only capture blurry images of Pluto
“The most recent surprise we had was with the Rosetta mission. Hubble had made a ‘shape model’ of Comet 67P but no-one expected it to look like a rubber duckie,” he told BBC News. “I am more than hopeful that we will get similar surprises with New Horizons – it’s what we should expect.”

Those surprises could include yet more moons (five are currently known) and possibly even rings like those seen around some of the bigger planets.

Pluto is currently 5bn km from Earth. It has taken New Horizons more than nine years to get to the dwarf’s doorstep.

Once the flyby is complete, the probe will be targeted at an even more distant object in the Kuiper Belt – the name given to the icy domain beyond the main planets. Scientists think this region of space, and beyond, may contain many thousands of Pluto-like objects. Some even speculate there are far-flung worlds that rival Mars and Earth in size.

The first optical navigation images should be back on Earth by Tuesday at the latest. They will show Pluto with its largest moon, Charon.

The clip below is an interesting look at humanities probing of the stars. From the BBC series Explorations

 

Mystery Mars haze baffles scientists

 

 

Mystery Mars haze baffles scientists

By Rebecca Morelle
Science Correspondent, BBC News

'War of the Worlds' type plume

The plume appeared twice in 2012, and stretched for 1,000km

A mysterious haze high above Mars has left scientists scratching their heads.

The vast plume was initially spotted by amateur astronomers in 2012, and appeared twice before vanishing.

Scientists have now analysed the images and say that say the formation, stretching for more than 1,000km, is larger than any seen before.

Writing in the journal Nature, the researchers believe the plume could be a large cloud or an exceptionally bright aurora.

However, they are unsure how these could have formed in the thin upper reaches of the Martian atmosphere.

“It raises more questions than answers,” said Antonio Garcia Munoz, a planetary scientist from the European Space Agency.

Around the world, a network of amateur astronomers keep their telescopes trained on the Red Planet.

They first spotted the strange plume in March 2012 above Mars’ southern hemisphere.

Damian Peach was one of the first stargazers to capture images of the phenomenon.

He told BBC News: “I noticed this projection sticking out of the side of the planet. To begin with, I thought there was a problem with the telescope or camera.

“But as I checked more of the images, I realised it was a real feature – and it was quite a surprise.”

Damian Peach was one of the first astronomers to image the plume

The vast, bright haze lasted for about 10 days. A month later, it reappeared for the same length of time. But it has not been seen since.

An international team of scientists has now confirmed the finding, but they are struggling to find an explanation.

One theory is that the plume is a cloud of carbon dioxide or water particles.

“We know there are clouds on Mars, but clouds, up to this point, have been observed up to an altitude of 100km,” Dr Garcia Munoz said.

“And we are reporting a plume at 200km, so it is significantly different. At 200km, we shouldn’t see any clouds, the atmosphere is too thin – so the fact we see it for 20 days in total is quite surprising.”

Another explanation is that this is a Martian version of the northern or southern lights.

Dr Garcia Munoz explained: “We know in this region on Mars, there have been auroras reported before. But the intensities we are reporting are much much higher than any auroras seen before on Mars or on Earth.

“It would be 1,000 times stronger than the strongest aurora, and it is difficult to come to terms that Mars has such an intense aurora.”

If either of these theories are right, he said, it would mean our understanding of Mars’ upper atmosphere is wrong.

He hopes that by publishing the paper, other scientists might also come up with explanations.

If they cannot, astronomers will have to wait for the plumes to return.

Close-up observations from telescopes or the spacecraft that are currently in orbit around the Red Planet could help to solve this Martian mystery.

Earth’s biodiversity is helping scientist to design vehicles that will travel through space and land on Mars and other planets. It’s called ‘bio-inspiration’ as this video clip shows.


Brazil Amazon: Drone to scan for ancient Amazonia

Brazil Amazon: Drone to scan for ancient Amazonia
By Jonathan Amos
BBC Science Correspondent, San Jose

Amazon Drone

The drone to be used in the project has a wingspan of about 3m

Scientists are to scan the Amazon forest in Brazil to look for evidence of occupation by ancient civilisations.

A drone will be sent up with a laser instrument to peer through the canopy for earthworks that were constructed thousands of years ago.

The UK-led project is trying to determine how big these communities were, and to what degree they altered the landscape.

The data is likely to inform policies on sustainable forest use today.

Researchers announced the initiative at the annual meeting of the American Association for the Advancement of Science in San Jose.

It has just won a 1.7m-euro (£1.25m; $1.9m) grant from the European Research Council.

The key quest is to try to understand the scale and activities of populations living in the late pre-Columbian period (the last 3,000 years before the Europeans arrived in the 1490s).

‘Cultural parkland’
The international team will endeavour to find more geoglyphs, which are large geometric patterns left in the ground.

More than 450 of these are known in places where the forest has been cleared.

No-one is really quite sure what these earthen circles, squares and lines represent. Perhaps, they were ceremonial centres. But what is certain is that they are evidence of collective behaviour.

“It’s a hot debate right now in New World archaeology,” said Dr Jose Iriarte from Exeter University, UK.

“While some researchers think that Amazonia was inhabited by small bands of hunter-gatherers and shifting cultivators who had a minimal impact on the environment, and that the forest we see today is pristine and untouched for thousands of years – mounting evidence is showing this may not be the case.

“This evidence suggests that Amazonia may have been inhabited by large, numerous, complex and hierarchical societies that had a major impact on the environment; what we call the ‘cultural parkland hypothesis’,” he told BBC News.

Amazon Forest un

The Mysterious Amazon © SMG

The drone to be used in the project has a wingspan of about 3m
Dr Iriarte’s project will fly its robotic plane across sample areas of forest.

This vehicle’s lidar instrument should reveal how many more geoglyphs remain hidden beneath still-canopied regions of Amazonia.

While some of the light from the lidar scatters back off the leaves, some is able to penetrate to the ground.

A smart algorithm can then be used to separate the two signals, digitally removing the trees to expose anything unusual beneath.

If candidate geoglyphs are confirmed in follow-up inspections, scientists would then move in to characterise signature changes that have been left in the soils and vegetation by the ancient inhabitants.

These “fingerprints” could then be searched for in satellite images, enabling a much broader swathe of Amazonia to be probed than is possible with just a small unmanned aerial vehicle. The arguments over the scale of occupation and its impacts should then be settled.

Amazon Forest

In normal airborne imagery only the tops of the trees are visible

The lidar makes a map of the canopy in digital form…

…which can then be removed to leave only that signal of the laser that made it through to the ground

The project is a partnership between agencies and institutions in Europe and, of course, in Brazil.

Mysterious geoglyphs

The expectation is that lessons learned will feed into policies for the management and sustainable use of the Amazon and its resources.

Dr Iriarte said it was not possible to gauge properly what future changes would be acceptable unless there was a fuller understanding of how the forest had been altered in the past.

“We want to see what is the human footprint in the forest and then inform policy, because it may be the case that the very biodiversity that we want to preserve is the result of the past historical manipulation of this forest,” he explained.

Video clip of the amazing amazon.

 

Meteorite is ‘hard drive’ from space

Meteorite is ‘hard drive’ from space

By Simon Redfern
BBC Science writer

Meteor

The Esquel meteorite consists of gem-quality crystals embedded in metal.

Researchers have decoded ancient recordings from fragments of an asteroid dating back billions of years to the start of the Solar System.

They found tiny “space magnets” in meteorites which retain a memory of the birth and death of the asteroid’s core.

Like the data recorded on the surface of a computer hard drive, the magnetic signals written in the space rock reveal how Earth’s own metallic core and magnetic field may one day die.

The work appears in Nature journal.

Using a giant X-ray microscope, called a synchrotron, the team was able to read the signals that formed more than four-and-a-half billion years ago, soon after the birth of the Solar System.

The meteorites are pieces of a parent asteroid that originally came from asteroid belt, between Mars and Jupiter.

They represents the left-over fragments of a planet that failed to form. The magnetic recording within it traps a signal of the precise moments when an iron-rich core formed in the asteroid as well as when it froze, killing its magnetic field.

The new picture of metallic core solidification in the asteroid provide clues about the magnetic field and iron-rich core of Earth.

Core values

“Ideas about how the Earth’s core evolved through [our planet’s] history are really changing at the moment,” lead researcher Dr Richard Harrison, from the University of Cambridge, told BBC News.

“We believe that Earth’s magnetic field is linked to core solidification. Earth’s solid inner core may have started to form at very interesting time in terms of the evolution of life on Earth.

“By studying an asteroid we get to see this in fast forward. We can see the start of core solidification in the magnetic records as well as its end, and start to think about how these processes work on Earth.”

Gravity

Magnetic field The Earth’s magnetic field will likely die off when the core completely freezes

The meteorites studied by the team originally fell to Earth in Argentina, and are composed of gem-quality crystals enclosed in a metallic matrix of iron and nickel.

Tiny particles, smaller than one thousandth the width of a human hair, trapped within the metal have retained the magnetic signature of the parent asteroid from its birth in the early Solar System.

“We’re taking ancient magnetic field measurements in nano-scale materials to the highest ever resolution in order to piece together the magnetic history of asteroids – it’s like a cosmic archaeological mission,” said Dr James Bryson, the paper’s lead author.

“Since asteroids are much smaller than Earth, they cooled much more quickly, so these processes occur on a shorter timescales, enabling us to study the whole process of core solidification.”

Don’t panic
Prof Wyn William, from the University of Edinburgh, who was not involved in the study, commented: “To be able to get a time stamp on these recordings, to get a cooling rate and the time of solidification, is fantastic. It’s a very nice piece of work.”

The key to the long-lived stability of the recording is the atomic-scale structure of the iron-nickel particles that grew slowly in the asteroid core and survived in the meteorites.

Scientists have attempted to synthesise the same iron-nickel structures in the lab, without widespread success so far. But their remarkable magnetic properties rival those of rare earth magnets, a key component of wind turbines and electric cars.

They may yet prove a route to making cheap, strong magnets without the need for scarce rare earth metals.

Making a final comment on the results, Dr Harrison said: “In our meteorites we’ve been able to capture both the beginning and end of core freezing, which will help us understand how these processes affected the Earth in the past and provide a possible glimpse of what might happen in the future.”

The Earth’s magnetic field will likely die off when the core completely freezes, and Earth will no longer be protected from the Sun’s radiation.

“There’s no need to panic” said Dr Harrison. “The core won’t completely freeze for billions of years, and chances are, the Sun will get us first.”


India’s Mars satellite ‘Mangalyaan’ sends first images

India’s Mars satellite ‘Mangalyaan’ sends first images

 

Mars

The first image of Mars taken by the Indian orbiter

India’s space agency has released its first picture of Mars, taken by its satellite which entered orbit around the Red Planet.

“The view is nice up here,” tweeted @isro. A handful of images have been sent by the Mangalyaan probe so far.

Part of its mission is to study the Martian atmosphere for signs of life.

It is the first time a maiden voyage to Mars has entered orbit successfully and it is the cheapest. Nasa’s latest Maven mission cost almost 10 times as much.

Media in India have hailed the venture as a “historic achievement”.

The Hindu newspaper reported that the probe had “beamed back about 10 pictures of the Red Planet’s surface which show some craters”.

Officials were quoted by the newspaper as saying the pictures were of “good quality”.

line
Analysis – Jonathan Amos, Science correspondent
India’s space programme has succeeded at the first attempt where others have failed – by sending an operational mission to Mars.

It is, without doubt, a considerable achievement. This is a mission that has been budgeted at 4.5bn rupees ($74m), which, by Western standards, is staggeringly cheap.

The American Maven orbiter that arrived at the Red Planet on Monday is costing almost 10 times as much.

Back in June, Indian Prime Minister Narendra Modi even quipped that India’s real-life Martian adventure was costing less than the make-believe Hollywood film Gravity.

Why India’s Mars mission is so cheap – and thrilling

Mars

Applause broke in the control room out as the news came through that the probe had entered Mars’s orbit

Reports said the camera was the first of the instruments being carried by the satellite to be switched on, a few hours after it entered into orbit.

India’s 1,350kg (2,970lb) robotic spacecraft, which undertook a 10-month-long 200-million-km journey, is equipped with five instruments.

They include a thermal imaging spectrometer to map the surface and mineral wealth of the planet, and a sensor to track methane – a possible sign of life – and other components of the atmosphere.

India has become the fourth nation or geo-bloc to put a satellite into orbit around Mars, and the first from Asia.

Only the US, Russia and Europe have previously sent missions to Mars.

Here’s a series of clips about the universe and what it looks like through some of the world’s biggest telescopes….


Nasa ‘flying saucer’ tests Mars tech

By Mike Wall, Senior Writer www.space.com

This artist’s concept shows the test vehicle for NASA’s Low-Density Supersonic Decelerator (LDSD), designed to test landing technologies for future Mars missions. A balloon will lift the vehicle to high altitudes, where a rocket will take it even higher, to the top of the stratosphere, at several times the speed of sound.
Credit: NASA/JPL-Caltech

A saucer-shaped vehicle that could help NASA land big payloads on the surface of Mars is about to take to the skies for the first time.

NASA hopes to launch its Low-Density Supersonic Decelerator (LDSD) test vehicle — which the agency has dubbed its own “flying saucer” — Thursday (June 5) from the U.S. Navy’s Pacific Missile Range Facility in Kauai, Hawaii. The balloon-aided liftoff was originally scheduled for today (June 3), but the weather did not cooperate.

“After years of imagination, engineering and hard work, we soon will get to see our Keiki o ka honua, our ‘boy from Earth,’ show us its stuff,” LDSD project manager Mark Adler, from NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, said in a statement. [NASA’s Inflatable Flying Saucer for Mars Landings (Photos)]

 

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