Dozen black holes found at galactic centre

A dozen black holes may lie at the centre of our galaxy, the Milky Way, researchers have said.

A new analysis provides support for a decades-old prediction that “supermassive” black holes at the centres of galaxies are surrounded by many smaller ones.

However, previous searches of the Milky Way’s centre, where the nearest supermassive black hole is located, have found little evidence for this.

Details appear in the journal Nature.

Charles Hailey from Columbia University in New York and colleagues used archival data from Nasa’s Chandra X-ray telescope to come to their conclusions.

They report the discovery of a dozen inactive and low-mass “binary systems”, in which a star orbits an unseen companion – the black hole.

The supermassive black hole at the centre of the Milky Way, known as Sagittarius A* (Sgr A*), is surrounded by a halo of gas and dust that provides the perfect breeding ground for the birth of massive stars. These stars live, die and could turn into black holes there.

In addition, black holes from outside the halo are believed to fall under the influence of Sgr A* as they lose their energy, causing them to be pulled into its vicinity, where they are held captive by its force.

Some of these bind – or “mate” – to passing stars, forming binary systems.

Previous attempts to detect this population of black holes have looked for the bright bursts of X-rays that are sometimes emitted by black hole binaries.

Faint and steady

“The galactic centre is so far away from Earth that those bursts are only strong and bright enough to see about once every 100 to 1,000 years,” said Prof Hailey.

Instead, the Columbia University astrophysicist and his colleagues decided to look for the fainter but steadier X-rays emitted when these binaries are in an inactive state.

“Isolated, unmated black holes are just black – they don’t do anything,” said Prof Hailey.

“But when black holes mate with a low mass star, the marriage emits X-ray bursts that are weaker, but consistent and detectable.”

A search for the X-ray signatures of low-mass black hole binaries in the Chandra data turned up 12 within three light-years of Sgr A*.

By extrapolating from the properties and distribution of these binaries, the team estimates that there may be 300-500 low-mass binaries and 10,000 isolated low-mass black holes surrounding Sgr A*.

Prof Hailey said the finding “confirms a major theory”, adding: “It is going to significantly advance gravitational wave research because knowing the number of black holes in the centre of a typical galaxy can help in better predicting how many gravitational wave events may be associated with them.”

Gravitational waves are ripples in the fabric of space-time. They were predicted by Albert Einstein’s general theory of relativity and detected by the Ligo experiment in 2015. One way these ripples arise is through the collision of separate black holes.

European Space Agency teams with ICEYE Finnish start-up

The European Space Agency is to work with Finnish start-up ICEYE on ways to exploit its novel radar satellites.

ICEYE-X1 was launched in January – the first of multiple spacecraft that will go up in the coming years.

About the size of a suitcase, these are the world’s smallest synthetic aperture radar satellites and cost a fraction of traditional platforms.

The Esa/ICEYE cooperation will focus on technology development and uses for the forthcoming constellation.

It will see future satellites – in particular, their radar antenna design – being tested at the agency’s technical centre (ESTEC) at Noordwijk, Netherlands.

Esa’s Earth observation headquarters (ESRIN) at Frascati, Italy, will also assist with calibration and validation of the ICEYE data.

  • UK satellite to make movies from space
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    The agency is keen to see how radar images from the mini-satellites can be drawn into the European Union’s Copernicus programme, the broad system of services that depend on space data.

    Areas of interest are likely to include maritime applications such as ship monitoring, and oil-spill and iceberg detection.

    “This is how we can best help so-called ‘New Space’ companies,” said Esa’s director of Earth observation, Josef Aschbacher.

    “They don’t need us to build their radar instrument or their satellites; they’re doing that themselves, and I would say faster than if we were involved. But there is a lot of engineering expertise here at Esa that is based on radar missions of more than 20 years,” he told BBC News.

    “We want to help ICEYE grow the market by testing and evaluating their value for Copernicus which is potentially a huge customer for them.”

    Esa’s own radar missions currently in service include the Sentinel 1a and 1b spacecraft.

    • In this preliminary flood analysis exercise image, ICEYE has combined and processed Esa’s Sentinel-1 satellite data with ICEYE-X1 satellite data to visualise potential change detection capabilities. The image features the River Seine as it ran past Paris-Orly airport in France at the start of the year when water levels were extremely high.

      ICEYE-X1’s bus, or chassis, which contains the radar instrument and spacecraft sub-systems, measures 80cm by 60cm by 50cm. Its radar antenna, after being unfolded in orbit, is 3.5m in length.

      These dimensions are much smaller than those of past radar missions.

      Like all New Space companies, the Helsinki-based outfit is exploiting the use of cheap electronics normally found in consumer products to reduce both the size and cost of its designs.

      The first satellite has now taken hundreds of images from an altitude of 505km.

      ICEYE is exploring how these pictures, and the analysis of them, could best benefit commercial partners.

      Radar’s great advantage is that it senses the ground in all weathers and at night.

      ICEYE wants to couple this vision with high temporal resolution, meaning a single spot on the Earth’s surface would be surveyed several times a day. Algorithms will scour the data to detect significant changes.

      High-repeat requires a network of satellites, and ICEYE envisages perhaps 30 platforms in orbit.

      Such a constellation could observe London or Paris, say, 15 times a day.

      Spatial resolution is important, too. ICEYE-X1 has been returning 10m-resolution pictures, meaning they see any features bigger than that. But iterations of the instrument and the radar antenna are expected to bring the resolution down to 3m.

      “ICEYE-X1 has far exceeded our expectations,” said Rafal Modrzewski, CEO and co-founder of ICEYE.

      “We did expect it to perform well, obviously; but for a first spacecraft from a start-up to perform so well – it’s been a great mission and a really exciting period for us,” he told BBC News.

      ICEYE-X2 is scheduled to go up in August and ICEYE-X3 is aiming for a November launch.

      ICEYE is working with a Polish company to part-manufacture ICEYE-X2.

      For ICEYE-X3, the entire bus will come from York Space Systems, a Colorado, US, concern.

      Mr Modrzewski said his company was trying to establish how much in-house building to do versus external sourcing.

      “We’re also looking into at least one more satellite because the sooner we get our constellation up and running, the sooner it will be providing our customers and partners with the capability. But we have to be careful. We don’t want to launch too fast and then fail.”

      Jonathan.Amos-INTERNET@bbc.co.uk and follow me on Twitter: @BBCAmos

Stephen Hawking’s final interview: A beautiful Universe

Last October I invited Prof Stephen Hawking to comment on the detection of gravitational waves from the collision of two neutron stars. It turned out to be his final broadcast interview.

The collision was a really big story for many reasons, not least because within minutes of the detection the world’s telescopes were trained on what was an incredible cosmic event.

This meant that as well as detecting the ripples in space-time from the merger, astronomers could see also for the first time what happens when two incredibly massive objects come together in a process that may be the only way of creating gold and platinum in the Universe.

It was definitely one for Prof Hawking to explain.

  • Einstein’s waves detected in star smash
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    In recent years, he made comments about climate change, space travel and artificial intelligence. His interviews always captivated audiences. I was lucky enough to have interviewed him many times and for me he was at his most enthralling when he was on ‘home turf’ – talking about the physics he so loved and bending our minds with the implications of new discoveries. And I was so touched and honoured to hear from his staff that he had always enjoyed our encounters.

    I was only able to use one answer in my news report and so the rest of his interview was not broadcast or published. Here it is now in full. He leaves us with his trademark, awe-inspiring take on a cosmos that, as we look through his eyes, we should view as both beautiful and mysterious.

    Tell us how important is the detection of two colliding neutron stars?

    It is a genuine milestone. It is the first ever detection of a gravitational wave source with an electromagnetic counterpart. It confirms that short gamma-ray bursts occur with neutron star mergers. It gives a new way of determining distances in cosmology. And it teaches us about the behaviour of matter with incredibly high density.

    What will we learn from the electromagnetic waves emanating from the collision?

    The electromagnetic radiation gives us a precise location on the sky. It also tells us the ‘redshift’ of the event. The gravitational waves tell us the luminosity distance. Combining these measures give us a new way of measuring distances in cosmology. This is the first rung of what will become a new cosmological distance ladder. The matter inside a neutron star is much denser than anything we can produce in a laboratory. The electromagnetic signal from merging neutron stars will tell us about the behaviour of matter at such high density.

    • What Hawking predicted about the future
    • Hawking: The science that made him famous
    • Obituary: Stephen Hawking

      Will it give us insights into how black holes form?

      The fact that a black hole can form from the merger of two neutron stars was known from theory. But this event is the first test, or observation. The merger probably produces a rotating, hyper-massive neutron star which then collapses to form a black hole.

      This is very different from other ways of forming black holes, such as in a supernova or when a neutron star accretes matter from a normal star. With careful analysis of the data and theoretical modelling on supercomputers, there is vast scope for new insights to be obtained about the dynamics of black hole formation and gamma-ray bursts.

      Will gravitational wave measurements bring us a greater insight of how space-time and gravity operates and so transform our understanding of the Universe?

      Yes, without a shadow of a doubt. An independent cosmological distance ladder may provide independent confirmation of cosmological observations or it may reveal huge surprises. Gravitational wave observations let us test general relativity in situations where a gravitational field is strong and highly dynamical. Some people think that general relativity needs modifying in order to avoid introducing dark energy and dark matter. Gravitational waves are a new way to search for a signature of possible modifications of general relativity. A new observational window on the Universe typically leads to surprises that cannot yet be foreseen. We are still rubbing our eyes, or rather ears, as we have just woken up to the sound of gravitational waves.

      • The day I thought we’d unplugged Stephen Hawking
      • Stephen Hawking: The book that made him a star

        Is the collision of neutron stars one of the very few ways, or possibly the only way, that gold is produced in Universe. Could this explain why it’s so rare on Earth?

        Yes, the collision of neutron stars is one way of producing gold. It can also be formed from fast neutron capture in supernovas. Gold is rare everywhere, not just on Earth. The reason it’s rare is that by nuclear-binding energy peaks at iron, making it hard to produce heavier elements in general. Also strong electromagnetic repulsion must be overcome by the nuclear force in order to form stable heavy nuclei like gold.

        Follow Pallab on Twitter

Mount Etna is ‘sliding towards the sea’

Europe’s most active volcano, Mount Etna, is sliding towards the sea.

Scientists have established that the whole structure on the Italian island of Sicily is edging in the direction of the Mediterranean at a rate of 14mm per year.

The UK-led team says the situation will need careful monitoring because it may lead to increased hazards at Etna in the future.

The group has published its findings in the Bulletin of Volcanology.

“I would say there is currently no cause for alarm, but it is something we need to keep an eye on, especially to see if there is an acceleration in this motion,” lead author Dr John Murray told BBC News.

  • Space project to monitor all volcanoes

    The Open University geologist has spent almost half a century studying Europe’s premier volcano.

    In that time, he has placed a network of high-precision GPS stations around the mountain to monitor its behaviour.

    This instrumentation is sensitive to millimetric changes in the shape of the volcanic cone; and with 11 years of data it is now obvious, he says, that the mountain is moving in an east-south-east direction, on a general track towards the coastal town of Giarre, which is about 15km away.

    Essentially, Etna is sliding down a very gentle slope of 1-3 degrees. This is possible because it is sitting on an underlying platform of weak, pliable sediments.

    Dr Murray’s team has conducted lab experiments to illustrate how this works. The group believes it is the first time that basement sliding of an entire active volcano has been directly observed.

    On the human scale, a movement of 14mm/yr – that is 1.4m over a hundred years – will seem very small, and it is. But geological investigations elsewhere in the world have shown that extinct volcanoes that display this kind of trend can suffer catastrophic failures on their leading flank as they drift downslope.

    Stresses can build up that lead eventually to devastating landslides.

    Dr Murray and colleagues stress such behaviour is very rare and can take many centuries, even thousands of years, to develop to a critical stage.

    Certainly, there is absolutely no evidence that this is about to happen at Etna. Local residents should not be alarmed, the Open University scientist said.

    “The 14mm/yr is an average; it varies from year to year,” he explained.

    “The thing to watch I guess is if in 10 years’ time the rate of movement has doubled – that would be a warning. If it’s halved, I’d say there really is nothing to worry about.”

    Of more immediate concern is the confounding effect this sliding could have for the day-to-day assessment of the volcano.

    Scientists get hints that eruptive activity is about to occur when magma bulges upwards and deforms the shape of the mountain. To gain an unambiguous view of this inflation, researchers will need to subtract the general E-S-E motion.

    Jonathan.Amos-INTERNET@bbc.co.uk and follow me on Twitter: @BBCAmos

Mount Etna is ‘sliding towards the sea’

Europe’s most active volcano, Mount Etna, is sliding towards the sea.

Scientists have established that the whole structure on the Italian island of Sicily is edging in the direction of the Mediterranean at a rate of 14mm per year.

The UK-led team says the situation will need careful monitoring because it may lead to increased hazards at Etna in the future.

The group has published its findings in the Bulletin of Volcanology.

“I would say there is currently no cause for alarm, but it is something we need to keep an eye on, especially to see if there is an acceleration in this motion,” lead author Dr John Murray told BBC News.

  • Space project to monitor all volcanoes

    The Open University geologist has spent almost half a century studying Europe’s premier volcano.

    In that time, he has placed a network of high-precision GPS stations around the mountain to monitor its behaviour.

    This instrumentation is sensitive to millimetric changes in the shape of the volcanic cone; and with 11 years of data it is now obvious, he says, that the mountain is moving in an east-south-east direction, on a general track towards the coastal town of Giarre, which is about 15km away.

    Essentially, Etna is sliding down a very gentle slope of 1-3 degrees. This is possible because it is sitting on an underlying platform of weak, pliable sediments.

    Dr Murray’s team has conducted lab experiments to illustrate how this works. The group believes it is the first time that basement sliding of an entire active volcano has been directly observed.

    On the human scale, a movement of 14mm/yr – that is 1.4m over a hundred years – will seem very small, and it is. But geological investigations elsewhere in the world have shown that extinct volcanoes that display this kind of trend can suffer catastrophic failures on their leading flank as they drift downslope.

    Stresses can build up that lead eventually to devastating landslides.

    Dr Murray and colleagues stress such behaviour is very rare and can take many centuries, even thousands of years, to develop to a critical stage.

    Certainly, there is absolutely no evidence that this is about to happen at Etna. Local residents should not be alarmed, the Open University scientist said.

    “The 14mm/yr is an average; it varies from year to year,” he explained.

    “The thing to watch I guess is if in 10 years’ time the rate of movement has doubled – that would be a warning. If it’s halved, I’d say there really is nothing to worry about.”

    Of more immediate concern is the confounding effect this sliding could have for the day-to-day assessment of the volcano.

    Scientists get hints that eruptive activity is about to occur when magma bulges upwards and deforms the shape of the mountain. To gain an unambiguous view of this inflation, researchers will need to subtract the general E-S-E motion.

    Jonathan.Amos-INTERNET@bbc.co.uk and follow me on Twitter: @BBCAmos

Mount Etna is ‘sliding towards the sea’

Europe’s most active volcano, Mount Etna, is sliding towards the sea.

Scientists have established that the whole structure on the Italian island of Sicily is edging in the direction of the Mediterranean at a rate of 14mm per year.

The UK-led team says the situation will need careful monitoring because it may lead to increased hazards at Etna in the future.

The group has published its findings in the Bulletin of Volcanology.

“I would say there is currently no cause for alarm, but it is something we need to keep an eye on, especially to see if there is an acceleration in this motion,” lead author Dr John Murray told BBC News.

  • Space project to monitor all volcanoes

    The Open University geologist has spent almost half a century studying Europe’s premier volcano.

    In that time, he has placed a network of high-precision GPS stations around the mountain to monitor its behaviour.

    This instrumentation is sensitive to millimetric changes in the shape of the volcanic cone; and with 11 years of data it is now obvious, he says, that the mountain is moving in an east-south-east direction, on a general track towards the coastal town of Giarre, which is about 15km away.

    Essentially, Etna is sliding down a very gentle slope of 1-3 degrees. This is possible because it is sitting on an underlying platform of weak, pliable sediments.

    Dr Murray’s team has conducted lab experiments to illustrate how this works. The group believes it is the first time that basement sliding of an entire active volcano has been directly observed.

    On the human scale, a movement of 14mm/yr – that is 1.4m over a hundred years – will seem very small, and it is. But geological investigations elsewhere in the world have shown that extinct volcanoes that display this kind of trend can suffer catastrophic failures on their leading flank as they drift downslope.

    Stresses can build up that lead eventually to devastating landslides.

    Dr Murray and colleagues stress such behaviour is very rare and can take many centuries, even thousands of years, to develop to a critical stage.

    Certainly, there is absolutely no evidence that this is about to happen at Etna. Local residents should not be alarmed, the Open University scientist said.

    “The 14mm/yr is an average; it varies from year to year,” he explained.

    “The thing to watch I guess is if in 10 years’ time the rate of movement has doubled – that would be a warning. If it’s halved, I’d say there really is nothing to worry about.”

    Of more immediate concern is the confounding effect this sliding could have for the day-to-day assessment of the volcano.

    Scientists get hints that eruptive activity is about to occur when magma bulges upwards and deforms the shape of the mountain. To gain an unambiguous view of this inflation, researchers will need to subtract the general E-S-E motion.

    Jonathan.Amos-INTERNET@bbc.co.uk and follow me on Twitter: @BBCAmos

How effective are earthquake early warning systems?

Earthquake early warning detection is more effective for minor quakes than major ones.

This is according to a new study from the United States Geological Survey.

Seismologists modelled ground shaking along California’s San Andreas Fault, where an earthquake of magnitude 6.5 or more is expected within 30 years.

They found that warning time could be increased for residents if they were willing to tolerate a number of “false alarms” for smaller events.

This would mean issuing alerts early in an earthquake’s lifespan, before its full magnitude is determined. Those living far from the epicentre would occasionally receive warnings for ground shaking they could not feel.

“We can get [greater] warning times for weak ground motion levels, but we can’t get long warning times for strong shaking,” Sarah Minson, lead author of the study, told BBC News.

“Alternatively, we could warn you every time there was an earthquake that might produce weak ground shaking at your location… A lot of baby earthquakes don’t grow up to become big earthquakes,” she added.

  • ‘Phone seismometers’ prove their worth
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    Earthquake early warning systems have been in place in Mexico and Japan for years. Now, a system called ShakeAlert is being developed for the west coast of North America.

    So how can it predict the unpredictable? In short, it can’t.

    “It’s a misnomer… because it’s not earthquake early warning, the earthquake has already happened… It’s ground motion early warning,” said Dr Minson.

    Earthquakes occur along tectonic plate boundaries and faults in the Earth’s crust – long fractures where friction has built up over time.

    Dr Lucy Jones, a seismologist who was not involved in the study, explained: “The whole fault doesn’t move at once. It starts at an epicentre and the rupture moves down the fault like how you would rip a piece of paper.”

    This release of energy moves in two parts.

    Primary waves (p-waves) accordion out first and fastest.

    They are followed by slower secondary, or s-waves, which cause the ground to ripple up and down – the shaking that people experience during a quake.

    Life on the line

    The physics of earthquakes is one of the reasons why a single, universal warning system hasn’t been rolled out across all quake prone countries.

    California and Japan have populations living directly alongside fault lines, and cannot waste precious seconds before warning their citizens.

    In both countries, the p-waves and some very rapid algorithms determine the potential magnitude and dispatch an alert.

    But in Mexico, the capital city is about 300km from the nearest tectonic plate boundary.

    This allows geologists to use a system that can take some more time to issue a warning. They wait to detect the s-waves.

    Sirens blare in the streets of Mexico City whenever ground shaking above M5 is detected.

    Better living through algorithms

    However, the country’s usually robust SASMEX early warning system didn’t have sufficient time to respond to last September’s second earthquake.

    The system can usually provide up to a minute’s warning but the M7.1 earthquake originated much nearer the city than usual. The ground began to shake almost immediately after the alarm was triggered.

    A new algorithm was being tested for the SASMEX system at the time, which could, in the future, issue a warning 8-10 seconds earlier.

    Similarly, Japanese seismologists have looked to improve their early warning system after the devastating 2011 M9 earthquake.

    Dr Mitsuyuki Hoshiba, who has developed the new PLUM algorithm launched this week, explained. “In PLUM method: strength of shaking is predicted directly from observed shaking, skipping the process of estimation of epicentre and magnitude.”

    This will, Dr Hoshiba says, reduce the problem of missed alarms for future earthquakes.

    The big one

    Back in California, work continues on ShakeAlert.

    It is due to have a limited public rollout later this year, supported by federal funding which was approved on Friday 23 March.

    The system will use both ground-based seismometers and satellite observations to provide the maximum warning time to populations on the west coast.

    The work done by Dr Minson and her colleagues shows that for San Francisco this may be about 50 seconds for minor shaking, or as little as eight seconds for a major earthquake.

    If the system is to be as sensitive as possible, false alerts may also become a necessary part of life for Californians in the future.

    Dr Cochran, who spent time in Mexico following the 2017 earthquakes, noted that “people wanted as much information as they could get, and they were not particularly bothered as long as they heard there was an earthquake associated with that alert.”

    Dr Jones agrees: “I do not believe that is a great shortcoming of early warning systems as long as it is understood… we need to invest in appropriate education for the general public about early warning for the information to be most effectively used.”

How effective are earthquake early warning systems?

Earthquake early warning detection is more effective for minor quakes than major ones.

This is according to a new study from the United States Geological Survey.

Seismologists modelled ground shaking along California’s San Andreas Fault, where an earthquake of magnitude 6.5 or more is expected within 30 years.

They found that warning time could be increased for residents if they were willing to tolerate a number of “false alarms” for smaller events.

This would mean issuing alerts early in an earthquake’s lifespan, before its full magnitude is determined. Those living far from the epicentre would occasionally receive warnings for ground shaking they could not feel.

“We can get [greater] warning times for weak ground motion levels, but we can’t get long warning times for strong shaking,” Sarah Minson, lead author of the study, told BBC News.

“Alternatively, we could warn you every time there was an earthquake that might produce weak ground shaking at your location… A lot of baby earthquakes don’t grow up to become big earthquakes,” she added.

  • ‘Phone seismometers’ prove their worth
  • Gravity signals show true size of giant earthquakes
  • History of deadly earthquakes

    Earthquake early warning systems have been in place in Mexico and Japan for years. Now, a system called ShakeAlert is being developed for the west coast of North America.

    So how can it predict the unpredictable? In short, it can’t.

    “It’s a misnomer… because it’s not earthquake early warning, the earthquake has already happened… It’s ground motion early warning,” said Dr Minson.

    Earthquakes occur along tectonic plate boundaries and faults in the Earth’s crust – long fractures where friction has built up over time.

    Dr Lucy Jones, a seismologist who was not involved in the study, explained: “The whole fault doesn’t move at once. It starts at an epicentre and the rupture moves down the fault like how you would rip a piece of paper.”

    This release of energy moves in two parts.

    Primary waves (p-waves) accordion out first and fastest.

    They are followed by slower secondary, or s-waves, which cause the ground to ripple up and down – the shaking that people experience during a quake.

    Life on the line

    The physics of earthquakes is one of the reasons why a single, universal warning system hasn’t been rolled out across all quake prone countries.

    California and Japan have populations living directly alongside fault lines, and cannot waste precious seconds before warning their citizens.

    In both countries, the p-waves and some very rapid algorithms determine the potential magnitude and dispatch an alert.

    But in Mexico, the capital city is about 300km from the nearest tectonic plate boundary.

    This allows geologists to use a system that can take some more time to issue a warning. They wait to detect the s-waves.

    Sirens blare in the streets of Mexico City whenever ground shaking above M5 is detected.

    Better living through algorithms

    However, the country’s usually robust SASMEX early warning system didn’t have sufficient time to respond to last September’s second earthquake.

    The system can usually provide up to a minute’s warning but the M7.1 earthquake originated much nearer the city than usual. The ground began to shake almost immediately after the alarm was triggered.

    A new algorithm was being tested for the SASMEX system at the time, which could, in the future, issue a warning 8-10 seconds earlier.

    Similarly, Japanese seismologists have looked to improve their early warning system after the devastating 2011 M9 earthquake.

    Dr Mitsuyuki Hoshiba, who has developed the new PLUM algorithm launched this week, explained. “In PLUM method: strength of shaking is predicted directly from observed shaking, skipping the process of estimation of epicentre and magnitude.”

    This will, Dr Hoshiba says, reduce the problem of missed alarms for future earthquakes.

    The big one

    Back in California, work continues on ShakeAlert.

    It is due to have a limited public rollout later this year, supported by federal funding which was approved on Friday 23 March.

    The system will use both ground-based seismometers and satellite observations to provide the maximum warning time to populations on the west coast.

    The work done by Dr Minson and her colleagues shows that for San Francisco this may be about 50 seconds for minor shaking, or as little as eight seconds for a major earthquake.

    If the system is to be as sensitive as possible, false alerts may also become a necessary part of life for Californians in the future.

    Dr Cochran, who spent time in Mexico following the 2017 earthquakes, noted that “people wanted as much information as they could get, and they were not particularly bothered as long as they heard there was an earthquake associated with that alert.”

    Dr Jones agrees: “I do not believe that is a great shortcoming of early warning systems as long as it is understood… we need to invest in appropriate education for the general public about early warning for the information to be most effectively used.”

Origin of ‘six-inch mummy’ confirmed

Tests on a six-inch-long mummified skeleton from Chile confirm that it represents the remains of a newborn with multiple mutations in key genes.

Despite being the size of a foetus, initial tests had suggested the bones were of a child aged six to eight.

These highly unusual features prompted wild speculation about its origin.

Now, DNA testing indicates that the estimated age of the bones and other anomalies may have been a result of the genetic mutations.

Details of the work have been published in the journal Genome Research.

In addition to its exceptionally small height, the skeleton had several unusual physical features, such as fewer than expected ribs and a cone-shaped head.

The remains were initially discovered in a pouch in the abandoned nitrate mining town of La Noria. From there, they found their way into a private collection in Spain.

Some wondered whether the remains, dubbed Ata after the Atacama region where they were discovered, could in fact be the remains of a non-human primate. A documentary, called Sirius, even suggested it could be evidence of alien visitations.

Genetic investigation

The new research puts those ideas to rest.

A scientific team analysed the individual’s genome – the genetic blueprint for a human, contained in the nucleus of cells.

They had already used this to confirm that the individual was human. Now, the team has presented evidence that Ata was a female newborn with multiple mutations in genes associated with dwarfism, scoliosis and abnormalities in the muscles and skeleton.

“What was striking and caused us to speculate early on that there was something strange about the bones was the apparent maturity of the bones (density and shape),” said Garry Nolan, a professor of microbiology and immunology at the Stanford University School of Medicine in California.

He told BBC News: “There was proportionate maturation of the bones, making the body look more mature despite the fact that the specimen was itself small. This discrepancy drove much of the research. So, we believe that one or more of the mutated genes was responsible for this.”

The results revealed four new single nucleotide variants (SNVs) – a type of genetic mutation – in genes that were known to cause bone diseases, like scoliosis or dislocations, as well as two more SNVs in genes involved in producing collagen.

Ata also had 10 pairs of ribs, rather than 12 – a feature that has never been seen in humans before.

“We actually believe the girl was stillborn or died immediately after birth,” said Prof Nolan.

“She was so badly malformed as to be unable to feed. In her condition, she would have ended up in the neonatal ICU.”

However, access to advanced medical care was probably unavailable in the remote Chilean region where she was found. The skeleton’s intact condition suggests it may be no more than 40 years old.

Future benefit

Prof Nolan began the scientific investigation of Ata in 2012, when a friend called saying he might have found an “alien”.

He explained: “While this started as a story about aliens, and went international – it’s really a story of a human tragedy. A woman had a malformed baby, it was preserved in a manner and then “hocked”, or sold.”

The scientists said that future studies of Ata had the potential to improve our understanding of the underlying basis of genetic skeletal disorders – with the potential to help others.

“Analysing a puzzling sample like the Ata genome can teach us how to handle current medical samples, which may be driven by multiple mutations,” said Atul Butte, director of the Institute for Computational Health Sciences at the University of California, San Francisco.

“When we study the genomes of patients with unusual syndromes, there may be more than one gene or pathway involved genetically, which is not always considered.”

Prof Nolan says further research into Ata’s precocious bone aging could one day benefit patients. “Maybe there’s a way to accelerate bone growth in people who need it, people who have bad breaks,” he said. “Nothing like this had been seen before. Certainly, nobody had looked into the genetics of it.”

He added: “I think it should be returned to the country of origin and buried according to the customs of the local people.”

Origin of ‘six-inch mummy’ confirmed

Tests on a six-inch-long mummified skeleton from Chile confirm that it represents the remains of a newborn with multiple mutations in key genes.

Despite being the size of a foetus, initial tests had suggested the bones were of a child aged six to eight.

These highly unusual features prompted wild speculation about its origin.

Now, DNA testing indicates that the estimated age of the bones and other anomalies may have been a result of the genetic mutations.

Details of the work have been published in the journal Genome Research.

In addition to its exceptionally small height, the skeleton had several unusual physical features, such as fewer than expected ribs and a cone-shaped head.

The remains were initially discovered in a pouch in the abandoned nitrate mining town of La Noria. From there, they found their way into a private collection in Spain.

Some wondered whether the remains, dubbed Ata after the Atacama region where they were discovered, could in fact be the remains of a non-human primate. A documentary, called Sirius, even suggested it could be evidence of alien visitations.

Genetic investigation

The new research puts those ideas to rest.

A scientific team analysed the individual’s genome – the genetic blueprint for a human, contained in the nucleus of cells.

They had already used this to confirm that the individual was human. Now, the team has presented evidence that Ata was a female newborn with multiple mutations in genes associated with dwarfism, scoliosis and abnormalities in the muscles and skeleton.

“What was striking and caused us to speculate early on that there was something strange about the bones was the apparent maturity of the bones (density and shape),” said Garry Nolan, a professor of microbiology and immunology at the Stanford University School of Medicine in California.

He told BBC News: “There was proportionate maturation of the bones, making the body look more mature despite the fact that the specimen was itself small. This discrepancy drove much of the research. So, we believe that one or more of the mutated genes was responsible for this.”

The results revealed four new single nucleotide variants (SNVs) – a type of genetic mutation – in genes that were known to cause bone diseases, like scoliosis or dislocations, as well as two more SNVs in genes involved in producing collagen.

Ata also had 10 pairs of ribs, rather than 12 – a feature that has never been seen in humans before.

“We actually believe the girl was stillborn or died immediately after birth,” said Prof Nolan.

“She was so badly malformed as to be unable to feed. In her condition, she would have ended up in the neonatal ICU.”

However, access to advanced medical care was probably unavailable in the remote Chilean region where she was found. The skeleton’s intact condition suggests it may be no more than 40 years old.

Future benefit

Prof Nolan began the scientific investigation of Ata in 2012, when a friend called saying he might have found an “alien”.

He explained: “While this started as a story about aliens, and went international – it’s really a story of a human tragedy. A woman had a malformed baby, it was preserved in a manner and then “hocked”, or sold.”

The scientists said that future studies of Ata had the potential to improve our understanding of the underlying basis of genetic skeletal disorders – with the potential to help others.

“Analysing a puzzling sample like the Ata genome can teach us how to handle current medical samples, which may be driven by multiple mutations,” said Atul Butte, director of the Institute for Computational Health Sciences at the University of California, San Francisco.

“When we study the genomes of patients with unusual syndromes, there may be more than one gene or pathway involved genetically, which is not always considered.”

Prof Nolan says further research into Ata’s precocious bone aging could one day benefit patients. “Maybe there’s a way to accelerate bone growth in people who need it, people who have bad breaks,” he said. “Nothing like this had been seen before. Certainly, nobody had looked into the genetics of it.”

He added: “I think it should be returned to the country of origin and buried according to the customs of the local people.”