Air Force awards ULA $1.18 billion contract to complete five Delta 4 Heavy NRO missions

The award covers the launch operations costs for five classified NRO missions — NROL-44, NROL-82, NROL-91, NROL-68 and NROL-70.

WASHINGTON — The Air Force Space and Missile Systems Center on Sept. 30 awarded United Launch Alliance a five-year $1.18 billion contract to complete five Delta 4 Heavy National Reconnaissance Office missions from 2020 through 2024.

The award covers the launch operations costs for five classified NRO missions — NROL-44, NROL-82, NROL-91, NROL-68 and NROL-70. The Air Force already had acquired five Delta 4 Heavy rockets for these missions under previous contracts with ULA.

Because Delta 4 Heavy launches take years to plan, the Air Force and the NRO divided the contract into two parts: Launch Vehicle Production Services (LVPS) and Launch Operations Support (LOPS). The $1.18 billion contract awarded Sept. 30 to ULA is for LOPS.

The Air Force had procured Delta 4 Heavy rockets for NROL-44 and NROL-82 in fiscal year 2017 under the Evolved Expendable Launch Vehicle Phase 1 Block Buy contract with ULA that officially ends Sept. 30, 2019. Both missions ran behind schedule and slipped to 2020, which pushed them beyond the Phase 1 contract’s period-of-performance and required the Air Force to award a separate LOPS contract.

The launch vehicle production contract for NROL-82 was awarded in April 2017 for $270.4 million and the launch vehicle for NROL-44 in December 2016 for $269.2 million. Three additional Delta 4 Heavy rockets were procured in October 2018 in a separate sole-source contract worth $467.5 million for NROL-91, NROL-68 and NROL-70.

The Sept. 30 LOPS contract covers all five missions and pays for infrastructure and launch pad maintenance and range support contractors at Vandenberg Air Force Base and Cape Canaveral Air Force Station, satellite encapsulation and propellants.

Altogether the contracts awarded for rocket production and launch service for the five missions add up to about $2.3 billion.

NROL-44 and NROL-82 are projected to launch in fiscal year 2020. NROL-91, NROL-68 and NROL-70 are forecast to launch in fiscal years 2022, 2023 and 2024 respectively.

Col. Robert Bongiovi, director of the Air Force Space and Missile Systems Center Launch Enterprise, told reporters Sept. 30 that these are the “last remnants of sole source contracts.” He said these five missions have “unique and complex launch requirements and are among the most important space assets in the nation.”

By separating the vehicle production and the launch operations contracts, the Air Force said it saved 11 months and hundreds of millions of dollars in costs over the five missions because it allowed ULA to begin procuring hardware and negotiate prices with suppliers in advance. It also gave the Air Force extra time to assess the scope of the work and negotiate a final LOPS contract with ULA. The five-year LOPS contract awarded Sept. 30 starts in fiscal year 2020, and options will be exercised annually.

Bongiovi said the NRO missions were sole-sourced to ULA because the Delta 4 was determined to be the only rocket that could satisfy those demands. NRO satellites require special handling at the launch site and complex integration studies to determine proper payload compatibility. “We are always trying to figure out how to introduce competition,” he said. In response to questions on whether SpaceX’s Falcon Heavy could have competed for these missions, Bongiovi said at the time these launches were acquired in 2016 and 2017, the Delta 4 Heavy was the only one able to meet the requirements.

Bongiovi said the Air Force wants to move away from sole-sourcing and transition to a competitive launch procurement program. Future launches will be competed under the National Security Space Launch Phase 2 Launch Service Procurement. Two providers will be selected in 2020 to split 60/40 all national security missions from 2022 to 2026. To win these contracts, companies have to demonstrate that they can meet the requirements for all national security missions projected for those five years. By the time the Delta 4 Heavy is taken out of service in 2025, the Air Force said both winners of Phase 2 will have to be able to compete for the heavy-lift “Category C” missions.

The only other certified launch provider to challenge ULA in the EELV Phase 1 procurement was SpaceX. The Falcon 9 launch vehicle was certified in May 2015. In Phase 1A of the EELV program SpaceX was awarded five GPS 3 missions, the first of which was launched in December.

The Sept. 30 contract award closes out the EELV program. Under the EELV Phase 1 Block Buy contract with ULA, the Air Force agreed to buy 35 launch vehicle booster cores over a five-year period. The associated infrastructure and support to launch rockets was funded under a separate contract known as EELV Launch Capability, or ELC.

That arrangement gave the Air Force flexibility to reschedule launches on the manifest of the Atlas 5 and the Delta 4 without incurring penalties. DoD at the time wanted to avoid the additional costs associated with the frequent launch delays caused by schedule slips in satellite programs. By paying for a capability to launch separately from launch hardware, DoD sought to ensure access to space regardless of payload delays

The National Defense Authorization Act for Fiscal Year 2016 directed the Air Force to discontinue the ELC contract by December 31, 2019 for Atlas 5 and December 31, 2020 for Delta 4 launch services.

Five missions awarded to ULA under EELV Phase 1 will be launched over the next five years, including the two Delta 4 Heavy launches for NROL-44 and NROL-82 and three Atlas 5 missions (NROL-101, AEHF-6 and AFSPC-7). The Air Force will announce a separate “completion contract” Oct. 1 for launch support operations for the three Atlas 5 missions.

A ULA spokesperson said in a statement that the contract awarded Sept. 30 to fly the five remaining Phase 1 Delta 4 Heavy missions  “includes a well-defined scope to ensure the Air Force and the NRO have the necessary capability to launch the remaining missions on schedule.”

#Space | https://sciencespies.com/space/air-force-awards-ula-1-18-billion-contract-to-complete-five-delta-4-heavy-nro-missions/

Infinite Powers: The Story Of Calculus

A rare look at the history and logic of calculus, how it was invented and developed, and what it reveals about the universe, the planet, its creators -- and, well, all of us

Cover: Infinite Powers: The Story of Calculus -- The Language of the Universe by Steven... [+] Strogatz.(Credit: Atlantic Books)

Atlantic Books

Calculus is one the most profound inventions in human history. It underlies most modern technologies such as radio, television, radar, GPS navigation, cell phones, and MRI imaging. It informs meteorology, epidemiology, biology and medicine. Thus, it is a subject that every educated person should have a conceptual understanding of, at least the very least.

In Steven Strogatz’s beautifully-written Infinite Powers: The Story of Calculus -- The Language of the Universe (Atlantic Books, 2019: Amazon US / Amazon UK), we learn about the conceptual framework upon which calculus is built and how it was developed throughout the ages to address specific challenges: from determining the area of a circle to making sure your space craft sticks its lunar landing.

We discover that the special genius of calculus is that it’s based upon breaking down complex, seemingly intractable problems into infinitely small, solvable, pieces, which then can be computed and tamed before reassembling them into the larger, much scarier, whole. But more than breaking things into infinitely tiny pieces, this strategy has made calculus into a powerful tool that has led to all sorts of technological advances and solutions to real-world problems -- solutions that most people never heard about in maths classes. For example, I was particularly interested by the lucid and fascinating discussion about how calculus played a role in the universal adoption of the triple drug cocktail to combat the maddening, seemingly insurmountable mutation rate of HIV/AIDS. Calculus also provided critical insights into the nature of the puzzling asymptotic stage of the HIV infection where, it turns out, there is a long-running, albeit delicate, balance in the pitched battle between production of new virus particles and their destruction by the immune system (pp. 218-225).

On a more theoretical level, Professor Strogatz’s thoughts about why synthesis is so much more difficult than analysis for problem solving was illuminating (pp. 102-103), especially when thinking about the relative ease of learning differential calculus compared to integral calculus.

For readers who don’t want to immerse themselves in the actual maths but who still want to appreciate the history and the reasoning that gave rise to calculus, this is the most accessible book on those topics published in many years. For serious students of calculus, Infinite Powers will give you the historical and conceptual grounding that is so often lacking in maths education these days, and in doing so, it could help you understand what the heck you are doing.

Infinite Powers: The Story Of Calculus | @GrrlScientist

#News | https://sciencespies.com/news/infinite-powers-the-story-of-calculus/

Elon Musk just unveiled wild Starship plans for "the Moon, Mars, and beyond"

Elon Musk, the founder and CEO of SpaceX, addressed planet Earth on Saturday night about his latest plans to "extend consciousness beyond Earth" using a towering steel spaceship.

Standing between two rockets that represented both the future of SpaceX and its nail-biting past, Musk delivered his talk to more than 100 people from the company's fast-developing launch site in Boca Chica, southeast Texas.

Behind Musk was a shorter rocket called Falcon 1, which – after three catastrophic failures in 2006, 2007, and 2008 – finally delivered a small payload into space for the first time. That mission's success also prevented Musk and SpaceX from going broke.

"Eleven years ago today SpaceX made orbit for the first time," Musk said of that first successful Falcon 1 launch, on September 28, 2008. "If that fourth launch had not succeeded, there would have been curtains. But fate smiled upon us that day."

Yet as he spoke, all eyes were fixed on the 164-foot-tall (50-metre-tall), stainless-steel rocket ship behind Musk that SpaceX had finished assembling only hours before his speech.

"I think this is the most inspiring thing I've ever seen," Musk said of the vehicle, called Starship Mark 1: a critical prototype for a planned system called Starship.

A complete Starship may stand 40 stories tall at a launch pad, ferry dozens of people into orbit at a time, and eventually send crews to the Moon and Mars.

"There are many troubles in the world, of course, and these are important, and we need to solve them. But we also need things that make us excited to be alive," Musk said.

"Becoming a space-faring civilisation – being out there among the stars – this is one of the things that I know makes me be glad to be alive."

"Do you want the future where we become a space-faring civilisation and are on many worlds, and are out there among the stars? Or one where we're forever confined to Earth?" he said.

"I say it is the first."

But Musk's audacious vision needs a vehicle to carry it out, and to him that vessel is Starship.

SpaceX has made radical changes to its Mars rocket over the past year

In September 2018, Musk presented a carbon-fibre version of a Mars vehicle called Big Falcon Rocket. He also introduced Yusaku Maezawa, a Japanese fashion billionaire, as a major funder of the system's development – and the person who will fly around the Moon in a SpaceX rocket in 2023.

A couple of months later, though, SpaceX abandoned the carbon-fibre design and switched to a stainless-steel variant. Musk announced the reimagined spacecraft as Starship that December.

Since then, SpaceX built and launched a crude prototype called Starhopper and finished Starship Mk 1 (which Musk said may fly in a month or so). Those prototypes are work toward a Starship system that's fully reusable – that way, no multi-million-dollar rocket parts are wasted, and the only major cost to launch is fuel.

"The critical breakthrough that is required for us to become a space-faring civilisation is to make space travel like air travel," Musk said. "This is basically the holy grail of space travel."

SpaceX posted a video to Twitter (below) on Saturday that imagines how Starship would work.

Starship will be the most powerful rocket in history, capable of carrying humans to the Moon, Mars, and beyond pic.twitter.com/LloN8AQdei

— SpaceX (@SpaceX) September 29, 2019

In the animation, a Starship vessel is stacked on top of a giant rocket booster, called Super Heavy, that's equipped with up to several dozen car-size Raptor rocket engines. The booster hauls Starship much of the way toward orbit, detaches, and falls back to Earth.

Once refueled, the booster then launches another Starship to meet the first one in orbit, refuel it with methane and oxygen – liquids Musk says can be mass-manufactured on Earth as well as Mars using carbon dioxide, water, and solar energy – and send it on its way.

The biggest changes to Starship's design include a refinement of its lower wings, flipper-like upper canards, and the addition of hexagon-shaped heat shield tiles lining the spacecraft's belly.

SpaceX got rid of three wings that also functioned as landing legs. Instead, Starship – as currently envisioned – now has six pop-out landing legs and two canard-like wings.

The wings and tiles are crucial to safeguarding Starship as it returns to Earth at 25 times the speed of sound and plows through the planet's atmosphere. This phase, called reentry, generates a searing-hot plasma that can destroy an unprotected spacecraft.

"For a reusable ship, you're coming in like a meteor. You don't want something that melts at a high temperature," Musk said, emphasising the need for steel (most rockets use aluminium or carbon-fibre). He also noted that stainless steel is about 50 times cheaper by weight than carbon-fibre composites.

Starship's redesigned wings should help the vehicle maintain lift, slow down more gradually, and spread out the heat of reentry, while the thermal tiles absorb that energy.

Once the ship reaches denser atmosphere, Musk said the wings will help steer Starship as it falls toward a landing pad.

"It just falls like a skydiver, and controls itself, and then it turns and just lands," Musk said. "It will be totally nuts to see that thing land."

Kimi Talvitie – a spaceflight enthusiast, software engineer, and artist – built an impressive 3D model of a "skydiving" Starship (below) using details Musk shared ahead of his presentation.

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'I think we could potentially see people fly next year'

Though Starship may be years away from being fully realised, Musk shared some shocking notions about how it may stack up against all other rockets – even SpaceX's own partly reusable Falcon 9 and Falcon Heavy launchers.

Musk calculated that, in an ideal scenario, one Starship system could launch to space and return three times per day, or about 1,000 times a year. Assuming each launch can fly about 150 tons of payload into orbit, that works out to about 150,000 tons per year.

That's more than 333 times the mass of the football field-size International Space Station.

Meanwhile, he said, all of Earth's rockets launching today might together deliver no more than 300 tons into space.

"We're talking about something that is, with a fleet of Starships, 1,000 times more than all Earth capacity combined. All other rockets combined would be 0.1 percent, including ours," Musk said.

"But you kind of need that if you're going to build a city on Mars. It's gotta be done."

The rapid reusability of the system, when Musk emphasised is essential, could also move Starship into an operational state much faster.

"I think we could potentially see people fly next year," Musk said. "We can do many flights to prove out the reliability very quickly."

Musk said SpaceX hasn't yet figured out how it plans to keep people alive inside its Starships, in terms of oxygen, food, water, and waste, let alone on the surface of Mars. But he added there's a definite need for "regenerative" life support systems, which recycle and conserve all the supplies humans need.

"I think for sure you'd want to have a regenerative life support system," Musk said. "Regenerative is kind of a necessity. I actually don't think its super hard to do that, relative to the spacecraft itself."

Despite Musk's optimism, though, fully functional regenerative life support systems have yet to be achieved in elaborate facilities on Earth, let alone in spacecraft.

Musk wants to save humanity before its 'window closes'

Musk's drive in creating Starship is not just about feeling good about the future, but also, in his mind, rescuing humanity from certain doom.

"As far as we know, this is the only place in this part of the galaxy, the Milky Way, where there is consciousness," Musk said of planet Earth.

He explained that it took about 4.5 billion years for that "consciousness" – we humans – to evolve, but that we have maybe a few hundred millions years left before our ageing Sun begins to expand, heat up Earth, and make our home planet uninhabitable.

Musk referred to this as a window of time for consciousness.

"That's all we've got, OK? Several hundred million years," Musk said. "If it took life an extra 10 percent longer for conscious life to evolve, it wouldn't have evolved at all, because it'd be incinerated by the Sun."

Though this or other humanity-destroying calamities are a long way off, Musk doesn't want to waste any time while our window to spread among the stars, as is evidenced by the frenetic pace of SpaceX's Starship rocket development program.

"I'm optimistic by nature, but there's some chance that window will not be open for long," Musk said. "I think we should become a multi-planet civilisation while that window is open.

"And if we do, I think the probable outcome for Earth is even better because then Mars could help Earth one day. I think we should really do our very best to become a multi-planet species, and we should extend consciousness beyond Earth, and we should do it now."

This article was originally published by Business Insider.

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#Space | https://sciencespies.com/space/elon-musk-just-unveiled-wild-starship-plans-for-the-moon-mars-and-beyond/

Realizing a giant magnetic field by moiré pattern engineering

(a) Schematic of a homobilayer moiré pattern, and periodic magnetic flux (green arrows) from the real-space Berry phase. The dashed rhombus denotes a supercell. (b) Upper panel: local atomic registries of the three locations A, B and C. Lower panel: corresponding layer distributions of conduction (C) and valence (V) band-edge electrons (yellow isosurfaces). The arrows indicate the layer pseudospin orientations. Credit: ©Science China Press

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Scientists at the University of Hong Kong and Hunan Normal University showed that, in homobilayer transition metal dichalcogenides, the real-space Berry phase from moiré patterns manifests as a periodic magnetic field. The field magnitude can reach hundreds of Tesla for a typical moiré period of 10 nanometers. For low energy carriers, this Berry phase induced magnetic field realizes a topological flux lattice for the quantum spin Hall effect.

In van der Waals layered structures, when two adjacent layers have small lattice mismatch and nearly aligned crystalline directions, the interlayer atomic registry will vary periodically on a length scale much larger than the monolayer lattice constant, known as the moiré superlattice. Engineering of the moiré pattern has become a powerful approach for tailoring electronic, optical and topological properties.

The nature of the moiré pattern as a spatial texture of atomic configurations suggests that the real-space Berry phase effect can be an indispensable part of moiré superlattice physics. In condensed matter materials, the internal quantum structure (spin or pseudospin) of a quasiparticle can have a dependence on its position and momentum, which can give rise to the real-space and momentum-space Berry phase effects. Some well-known manifestations of the momentum-space Berry phase are the anomalous Hall and spin Hall effects in homogeneous crystals. Meanwhile, spatial inhomogeneity can give rise to the real-space Berry phase which is the total flux of the Berry curvature through a surface enclosed by a loop. The real-space Berry curvature acts as a magnetic field, which can also lead to Hall current. Such topological Hall effects have attracted remarkable interest, and have been observed in magnetization skyrmion and domain structures.

Recently, in a research article published in National Science Review, scientists at the University of Hong Kong, Hong Kong, China, and at the Hunan Normal University in Hunan, China present the possibility of realizing giant magnetic field by moiré pattern engineering. Co-authors Hongyi Yu, Mingxing Chen and Wang Yao showed that, in homobilayer transition metal dichalcogenides, the real-space Berry phase from moiré patterns manifests as a periodic magnetic field, with the magnetic flux per moiré supercell being a quantized value. In a moiré pattern introduced by a uniaxial strain, the magnetic flux has a different sign from that introduced by a twisting or biaxial strain, although they can have the same potential landscape. The field magnitude scales inversely with the square of the moiré period, and can reach hundreds of Tesla for a typical moiré period of 10 nanometers. Remarkably, the real-space profile of the moiré magnetic field can be continuously tuned by an interlayer electric bias. Under a modest electric bias, a topological transition occurs where the magnetic flux per supercell has a quantized jump (from ±2π to 0).

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Three renowned scientists: Heusler, Weyl and Berry

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More information:
Hongyi Yu et al, Giant magnetic field from moiré induced Berry phase in homobilayer semiconductors, National Science Review (2019). DOI: 10.1093/nsr/nwz117

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Realizing a giant magnetic field by moiré pattern engineering (2019, September 30)
retrieved 30 September 2019
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#Physics | https://sciencespies.com/physics/realizing-a-giant-magnetic-field-by-moire-pattern-engineering/

What Earth's changing climate can teach us about altering the surface of Mars

Ozone layer. Credit: NASA

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In a rare instance of environmental success, the United Nations has just announced it believes the damage to the Earth's protective ozone layer will be fully restored by the year 2050. This stands in stark contrast to the increasing alarm over the climate emergency, caused by an increasing greenhouse effect.

Both the ozone layer and the greenhouse effect ultimately help control how much ultra-violet (UV) radiation from the sun reaches the Earth's surface, and how much infra-red (IR) radiation escapes to space. Both these forms of radiation have a critical impact on the habitability of a rocket planet.

Clearly controlling this radiation is a pressing issue on Earth. But it also presents a challenge for those who dream of colonising Mars.

Ultra-violet radiation is a form of light which has a wavelength ranging from 10—400 nanometers (1nm is 0.000000001 metres in length). This is shorter and more energetic than visible light. By contrast, the wavelength of a typical 4G phone network is a few tens of centimeters.

Solar-UV can drive the production of the essential Vitamin D in human skin, but excess levels can cause an array of health problems including sunburn, skin cancer and cataracts. It can also damage plants and harm crop production.

On Earth, almost all solar UV is absorbed by the ozone layer, a region of the Earth's atmosphere extending from about 15–30km in altitude. Without it, life on Earth would be in a lot of trouble.

Ozone is a naturally occurring molecule consisting of three oxygen atoms. The formation of this molecule is carefully balanced by a process called the Chapman cycle, in which ultraviolet light breaks the ozone down into a single oxygen atom and an oxygen molecule. Natural factors can act as catalysts for this such as volcanic activity and the Earths radiation belts.

The first observations that the ozone balance was in trouble were made in the 1980s. It was determined that the widespread use and emission of certain chemicals like chloroflourocarbons had caused severe damage to the ozone layer.

This prompted the international community to adopt the Montreal Protocol in 1987—so far the only UN agreement ever ratified by every member state.

IR radiation has a subtly different effect on Earth and other planets. All objects emit a range of light depending on their temperature. An object at an average temperature of a million degrees would primarily emit x-rays (as some star systems do).

The sun, at an average temperature of 5,700°C, emits most strongly in visible light (specifically in yellow), while objects at room temperature emit in IR. This is why people show up clearly in an infra-red camera.

Mars' surface—a harsh environment. Credit: NASA

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Sunlight, primarily at visible wavelengths, passes through the atmosphere and warms the Earth's surface. To maintain thermal equilibrium, the Earth then emits light back into space, but it does so in IR. Certain molecules in the atmosphere let a large amount of visible light pass through (which is why they are invisible to the human eye) but reflect back or scatter the IR light emitted by the surface—making the surface warmer.

The chemicals involved in this process are what we know as greenhouse gases, the most commonly known is carbon dioxide, but methane and nitrous oxide are also important. What complicates the climate issue is that water vapour and ozone itself are all greenhouse gases too.

This is one of the many factors that make climate modeling a very complex topic. The greenhouse effect itself is usually described as a bad thing, but it is actually essential to life. Without any greenhouse effect, it is relatively easy to show that the Earth would be at an average temperature of -24°C, instead of our current 14°C.

Like many natural processes though, human activity has modified the greenhouse effect such that this essential feature of our planet's habitability is now becoming dangerous. We have ample evidence that humans have increased the amount of greenhouse gases in the atmosphere, and as a result, the global average temperature.

Lessons for colonizers

The challenge for future colonists hoping to live on Mars is quite the reverse of that on Earth. Its thin atmosphere means that even though there is a large concentration of carbon dioxide, the greenhouse effect is quite weak and needs to be boosted. But a recent study has shown that even if the remaining carbon dioxide in rocks on Mars was vapourised and put into the atmosphere, there would not be enough of it to generate a sufficient greenhouse effect to make the planet warm enough to live on.

Compared with Earth, there is also very little ozone on Mars, and the thin Martian atmosphere allows much more solar-UV to reach the surface. So intense is this radiation that the top few centimeters of Martian soil are essentially sterilised once a day, with any complex molecules that might be useful for life being destroyed.

So what could we do to make the climate more similar to Earth's? Previous ideas have included installing a giant magnet in space near Mars to protect the atmosphere and firing nuclear weapons at the surface.

A recent paper suggests we could use silica aerogel—a synthetic and ultralight material made by taking a gel and replacing the liquid component with a gas—to cover regions of the surface. This would in effect function as an artificial ozone layer, being almost transparent in visible light but blocking UV.

The use of silica aerogel would also rapidly heat up the ground underneath it to above the freezing point of water by way of an artificial greenhouse effect. Placing silica aerogel shields over ice-rich areas of the surface would generate an environment suitable for plant growth, with minimal human intervention.

This alone cannot terraform the red planet, as the Martian atmosphere is constantly being lost to the solar wind. However, it would at least provide a much less hostile environment, on a smaller scale, for future visitors. While still a difficult prospect, this is currently the most practical way of making areas of Mars a less extreme environment.

Ultimately, the success of the Montreal Protocol demonstrates both the viability of collective international action to solve an environmental problem, and that environmental modification is possible on a planetary scale in quite a short span of time. It also demonstrates clearly just how sensitive planetary environmental processes can be to artificial changes, for good or ill.

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Why even a small change in Earth's carbon dioxide makes a big difference

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What Earth's changing climate can teach us about altering the surface of Mars (2019, September 30)
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#Biology | https://sciencespies.com/biology/what-earths-changing-climate-can-teach-us-about-altering-the-surface-of-mars/

Faster-than-light speeds could be why gamma-ray bursts seem to go backwards in time

Time, as far as we know, moves only in one direction. But last year, researchers found events in some gamma-ray burst pulses that seemed to repeat themselves as though they were going backwards in time.

Now, new research suggests a potential answer for what might be causing this time reversibility effect. If waves within the relativistic jets that produce gamma-ray bursts travel faster than light - at 'superluminal' speeds - one of the effects could be time reversibility.

Such speeding waves could actually be possible. We know that when light is travelling through a medium (such as gas or plasma), its phase velocity is slightly slower than c - the speed of light in a vacuum, and, as far as we know, the ultimate speed limit of the Universe.

Therefore, a wave could travel through a gamma-ray burst jet at superluminal speeds without breaking relativity. But to understand this, we need to back up a little to look at the source of those jets.

Gamma-ray bursts are the most energetic explosions in the Universe. They can last from a few milliseconds to several hours, they're extraordinarily bright, and we don't yet have a comprehensive list of what causes them.

We know from the 2017 observations of colliding neutron stars that these smash-ups can create gamma-ray bursts. Astronomers also think such bursts are produced when a massive, rapidly spinning star collapses into a black hole, violently ejecting material into the surrounding space in a colossal hypernova.

That black hole is then surrounded by a cloud of accretion material around its equator; if it's rotating quickly enough, the fallback of the initially exploded material will result in relativistic jets shooting from the polar regions, blasting through the outer envelope of the progenitor star before producing gamma-ray bursts.

Now, back to those waves travelling faster than light.

We know that, when travelling through a medium, particles can move faster than light does. This phenomenon is responsible for the famous Cherenkov radiation, often seen as a distinctive blue glow. That glow - a 'luminal boom' - is produced when charged particles such as electrons move faster through water than the phase velocity of light.

Astrophysicists Jon Hakkila of the College of Charleston and Robert Nemiroff of the Michigan Technological University believe that this same effect can be observed in gamma-ray burst jets, and have conducted mathematical modelling to demonstrate how.

"In this model an impactor wave in an expanding gamma-ray burst jet accelerates from subluminal to superluminal velocities, or decelerates from superluminal to subluminal velocities," they write in their paper.

"The impactor wave interacts with the surrounding medium to produce Cherenkov and/or other collisional radiation when travelling faster than the speed of light in this medium, and other mechanisms (such as thermalised Compton or synchrotron shock radiation) when travelling slower than the speed of light.

"These transitions create both a time-forward and a time-reversed set of [gamma-ray burst] light curve features through the process of relativistic image doubling."

Such relativistic image doubling is thought to occur in Cherenkov detectors. When a charged particle travelling at near light-speed enters water, it moves faster than the Cherenkov radiation it produces, and therefore can hypothetically appear to be in two places at once: one image appearing to move forward in time and the other appearing to move backwards.

Mind you, this doubling has not yet been experimentally observed. But if it does occur, it could also be responsible for producing the time-reversibility seen in gamma-ray burst light curves, occurring both when the impactor wave travelling through the jet medium accelerates to speeds faster than light, and decelerates to subluminal speeds.

More work is needed, of course. The researchers assumed that the impactor responsible for creating a gamma-ray burst would be a large-scale wave produced by changes in, say, density, or the magnetic field. That will need further analysis. And if the plasmas involved aren't transparent to superluminal radiation, all bets are off.

However, the researchers said, their model provides better explanations for the characteristics of gamma-ray burst light curves than models that don't include time reversibility.

"Standard gamma-ray burst models have neglected time-reversible light curve properties," Hakkila said. "Superluminal jet motion accounts for these properties while retaining a great many standard model features."

The research has been published in The Astrophysical Journal.

#Space | https://sciencespies.com/space/faster-than-light-speeds-could-be-why-gamma-ray-bursts-seem-to-go-backwards-in-time/

New tool provides critical information for addressing the global water crisis

Credit: CC0 Public Domain

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The World Economic Forum lists water crises among the top 10 most likely and impactful global risks. Most water metrics to date have only focused on water quality or water availability at national and regional scales. There has been a critical gap, though, in the ability to identify which households experience issues with reliably accessing safe water in sufficient quantities for all household uses, from drinking and cooking to bathing and cleaning—until now.

Northwestern University anthropologist Sera Young is leading a multi-disciplinary, international team of more than 40 researchers, which has developed a new tool that can fill this data gap and provide actionable, policy relevant information to address the global water crisis.

The 12-item Household Water Insecurity Experiences Scale (HWISE) quantifies experiences of household water insecurity in an equivalent way across low- and middle-income countries. Based on data from more than 8,000 households in 23 countries, the HWISE Scale measures the multiple components of water insecurity (adequacy, reliability, accessibility and safety) across disparate cultural and ecological settings. In addition, it only takes 3 to 5 minutes to ask the 12 simply phrased items.

The questions prompt respondents to reply "never, rarely, sometimes, often or always" to experiences with water insecurity in the last four weeks, including:

• How frequently did you or anyone in your household worry you would not have enough water for all of your household needs?
• How frequently did you change what was being eaten because there were problems with water (e.g. for washing foods, cooking, etc.)?
• In the last 4 weeks, how frequently has your main water source been interrupted or limited (eg, water pressure, less water than expected, river dried up)?

With these responses, a water insecurity score can be generated for each household. These data can then be used to better understand the prevalence of water insecurity, its causes and consequences, and to inform policy development.

"Our ability to quantify experiences with food insecurity have been transformative of our understanding of the prevalence and consequences of worry about food," said Young, lead author of the study and associate professor of anthropology and global health in the Weinberg College of Arts and Sciences at Northwestern. "We expect this metric to be similarly transformative for water."

The researchers have found that higher HWISE Scale scores (i.e., greater water insecurity) are strongly associated with greater food insecurity and stress, lower economic productivity, physical injury, altered infant feeding practices and adverse health.

"Given the power of the HWISE Scale to benchmark global household water insecurity, as well as inform national and regional policy, we are partnering with UNESCO and Gallup to raise resources for the inclusion of the tool in the Gallup World Poll," said Young, also a faculty fellow with the University's Institute for Policy Research. "We also seek to implement the scale in nationally representative surveys. Further, numerous NGOs are currently using the tool to monitor and evaluate ongoing projects and plan to share their findings soon."

"The Household Water Insecurity Experiences (HWISE) Scale: Development and Validation of a Household Water Insecurity Measure for Low-income and Middle-income Countries" published today (Sept. 30) in BMJ Global Health.

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A fun new paper says Planet 9 could actually be a primordial black hole

At the edge of our Solar System, some unknown object is manipulating the paths of chunks of ice as they circle the Sun.

These objects' oval-shaped orbits all point in the same direction and tilt the same way, suggesting that an unseen force is herding them.

At first, scientists thought the culprit was a mysterious planet, which they dubbed Planet Nine (though some call it Planet X).

But a new paper suggests the gravitational pull could come from a primordial black hole – a type of small black hole that scientists have theorised formed during the Big Bang.

Although the existence of primordial black holes has not been confirmed, some scientists think the Universe is teeming with them. If they exist, such black holes could make up the 80 percent of the Universe that scientists can't see.

They know this "dark matter" exists because its gravity pulls on things throughout the Universe.

A new paper posted on Tuesday on arXiv, an online repository for research that has not been peer-reviewed, suggests that Planet Nine could be one of these ancient black holes. The researchers proposed new ways to hunt down this mysterious missing piece.

"Once you start thinking about more exotic objects, like primordial black holes, you think in different ways," James Unwin, a theoretical physicist and coauthor of the paper, told Gizmodo.

"We advocate that rather than just looking for it in visible light, maybe look for it in gamma rays. Or cosmic rays."

Planet 9 explains distant objects' weird orbits

At the fringes of our Solar System are thousands of small icy bodies that make up a region astronomers call the Kuiper Belt. Six of those objects appear to have bizarre orbits that indicate some unknown source of gravity is tugging on them.

In 2016, computer simulations and mathematical models revealed that the culprit could be a mysterious distant planet we've never seen: Planet Nine.

In that study, the planetary scientists Konstantin Batygin and Michael Brown calculated that Planet Nine's gravitational pull means it could have up to 10 times the mass of Earth.

On average, the mysterious body orbits the Sun at a distance 20 times farther than Neptune – about 18.6 billion miles. It could take between 10,000 and 20,000 years for it to complete one trip around the Sun. (Pluto, by comparison, takes 248 years to complete its orbit.)

Batygin and Brown suggested that Planet Nine could have formed in the same way as the gas giants we know well – Jupiter, Saturn, Uranus, and Neptune – starting as an ice core, then grabbing all the gas around it.

Planet Nine may have gotten too close to Jupiter or Saturn, they suggested, and was flung out to the edges of the Solar System, where it now follows an eccentric orbit and influences the Kuiper Belt objects.

Since the mysterious world exerts such a powerful gravitational force on a large region of the Solar System, Brown called it "the most planet-y of the planets in the whole Solar System." But that may not be the case.

Rather than a planet, it could be a primordial black hole

For the new study, researchers looked at data on the six Kuiper Belt objects' bizarre orbits and also incorporated recent observations about how light travelling through the Solar System appears to be bending because of an object (or objects) that scientist haven't accounted for.

Both of these strange phenomena are likely caused by the interference of unknown objects, each with similar mass. So a primordial black hole could be to blame for both, the study suggested. It could be one black hole the size of a bowling ball with the mass of 10 Earths, or a number of smaller primordial black holes that add up to that mass.

The researchers also said that a dense group of free-floating planets outside our Solar System could explain the light bending; by that logic, Planet Nine could be one of those free roamers that was captured by our Solar System.

Really, Batygin told Gizmodo, Planet Nine could be any kind of low-visibility object with the right mass.

"Planet Nine could be a five-Earth-mass hamburger," he said. "But a black hole the size of your wallet is a bit harder to find."

The scientists behind the new study said that direct observations of the mysterious object ⁠- if astronomers can find it ⁠- could help determine whether it's a planet or black hole.

So the hunt for Planet Nine, they suggested, should include a search for moving sources of x-rays, gamma rays, and other types of radiation, since those clues could indicate the edges of a black hole.

If scientists detect such signals, they could find out whether Planet Nine has been a black hole all along.

This article was originally published by Business Insider.

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Here's how to write a good science paper, according to a bestselling novelist

Cormac McCarthy knows a thing or two about good writing.

He's the visionary who gave us The Road, No Country for Old Men, and a list of other acclaimed novels. He's won the Pulitzer Prize, the National Book Award, and just about every other literature award; film adaptations of his works have been seen by millions of people around the world.

On top of all this, it turns out McCarthy has also found time to moonlight as a copy editor for scientific papers, collaborating with researchers at the Santa Fe Institute (SFI) in New Mexico for the past two decades – in addition to editing the work of other prominent scientists, including Harvard physicist Lisa Randall.

We know this thanks to a fascinating article by SFI researchers Van Savage and Pamela Yeh, who have shared a condensed list of McCarthy's views on what makes for good scientific writing.

If you want to potentially improve your own writing (not necessarily science papers), you really should read Savage and Yeh's list, which they based on their history of working with the novelist. We've handpicked 10 of our favourite tips below.

Use minimalism to achieve clarity
McCarthy has a famously distinct style, and is extremely minimalist with punctuation. In that vein, McCarthy says you should remove extra words or punctuation whenever you can, as long as the sense of meaning is preserved.

Limit each paragraph to a single message
You don't want too much going on in a single block of text. According to McCarthy, you should only explore one single message or idea in each paragraph.

Keep sentences short, simply constructed and direct
Cut down on extraneous language wherever possible, using concise and clear sentences to make your point.

Don't slow the reader down
In McCarthy's view, things like jargon, footnotes, and repetitious language all serve as distractions that only get in the way of the reader's experience.

Don't over-elaborate
There's no need to say the same thing multiple times, or use multiple words to convey effectively the same message.

Refer to spoken language and common sense
"It's more important to be understood than it is to form a grammatically perfect sentence," Savage and Yeh say, so you can often forgo formal grammar (within reason) if more casual, spoken English makes your point clearly.

Commas denote pauses
Much like the above point about spoken language, commas in speech denote pauses in speech. You can strategically use commas in your writing the same way to distinguish clauses.

Choose concrete language and examples
Simple visual ideas, like a red balloon, are much easier for a reader to understand than ambiguous concepts that are hard or impossible to visualise.

Read your work aloud when you're done
And find a good editor you trust.

Try to write the best version of your paper
Pleasing yourself is a more achievable goal than pleasing an anonymous reader in your imagination.

Those are 10 selections from McCarthy's words of wisdom – as remembered by Savage and Yeh – but be sure to check out their full listing, which has lots more important points to remember.

#Humans | https://sciencespies.com/humans/heres-how-to-write-a-good-science-paper-according-to-a-bestselling-novelist/

Toward safer, more effective cancer radiation therapy using X-rays and nanoparticles

Precisely tuned X-ray can target give cancer cells more effective punch without harming body's surface, using gadolinium loaded silicon porous silica particles. Credit: Mindy Takamiya

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An element called gadolinium delivered into cancer cells releases killer electrons when hit by specially tuned X-rays. The approach, published in the journal Scientific Reports, could pave the way towards a new cancer radiation therapy.

"Our method opens up the possibility of selectively amplifying the effect of X-ray radiation at the tumor site," says Kotaro Matsumoto of Kyoto University's Institute for Integrated Cell-Material Sciences (iCeMS), who developed the technique with Fuyuhiko Tamanoi and colleagues in Japan, Vietnam, and the U.S. "This solves one of the major problems of current radiation therapies, where only a small amount of X-rays actually reach the tumor."

Conventional radiation therapies employ polychromatic X-rays, consisting of various energy levels, with low-energy X-rays failing to penetrate the body's surface. Monochromatic X-rays, on the other hand, have the same precisely tuned energy level. If they could be aimed at electron-releasing chemical elements inside tumors, they could be damaging.

To achieve this, the researchers used specially designed silica nanoparticles that were loaded with the chemical element gadolinium. The cancer cells in a 3-D tumor culture effectively consumed the particles after one day of incubation. The particles specifically located just outside tumor cell nuclei, where their most critical machinery is found.

At the SPring-8 synchrotron facility in Harima, Japan, the researchers aimed monochromatic X-rays at tumor samples containing gadolinium-loaded nanoparticles.

X-rays tuned to an energy level of 50.25 kiloelectron volts (keV) that targeted the samples for 60 minutes completely destroyed the cancer cells two days following irradiation.

Tuning the X-rays to an energy level just below 50.25keV did not have the same effect. The researchers explain that the X-rays are specifically tuned so that their energy can be absorbed by gadolinium. When they hit it, gadolinium releases low-energy electrons into the cancer cell, damaging its vital components, including DNA, and killing it.

The X-rays had no effect on cells that did not contain gadolinium-loaded nanoparticles.

"Our study demonstrates that a new type of radiation therapy for cancer can be developed," says Tamanoi. "We can expect radiation therapy with increased efficacy and less side effects."

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Fragmenting ions and radiation sensitizers

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Kotaro Matsumoto et al. Destruction of tumor mass by gadolinium-loaded nanoparticles irradiated with monochromatic X-rays: Implications for the Auger therapy, Scientific Reports (2019). DOI: 10.1038/s41598-019-49978-1

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How to dismantle a nuclear bomb: Team successfully tests new method for verification of weapons reduction

Credit: CC0 Public Domain

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How do weapons inspectors verify that a nuclear bomb has been dismantled? An unsettling answer is: They don't, for the most part. When countries sign arms reduction pacts, they do not typically grant inspectors complete access to their nuclear technologies, for fear of giving away military secrets.

Instead, past U.S.-Russia arms reduction treaties have called for the destruction of the delivery systems for nuclear warheads, such as missiles and planes, but not the warheads themselves. To comply with the START treaty, for example, the U.S. cut the wings off B-52 bombers and left them in the Arizona desert, where Russia could visually confirm the airplanes' dismemberment.

It's a logical approach but not a perfect one. Stored nuclear warheads might not be deliverable in a war, but they could still be stolen, sold, or accidentally detonated, with disastrous consequences for human society.

"There's a real need to preempt these kinds of dangerous scenarios and go after these stockpiles," says Areg Danagoulian, an MIT nuclear scientist. "And that really means a verified dismantlement of the weapons themselves."

Now MIT researchers led by Danagoulian have successfully tested a new high-tech method that could help inspectors verify the destruction of nuclear weapons. The method uses neutron beams to establish certain facts about the warheads in question—and, crucially, uses an isotopic filter that physically encrypts the information in the measured data.

A paper detailing the experiments, "A physically cryptographic warhead verification system using neutron induced nuclear resonances," is being published today in Nature Communications. The authors are Danagoulian, who is the Norman C. Rasmussen Assistant Professor of Nuclear Science and Engineering at MIT, and graduate student Ezra Engel. Danagoulian is the corresponding author.

High-stakes testing

The experiment builds on previous theoretical work, by Danagoulian and other members of his research group, who last year published two papers detailing computer simulations of the system. The testing took place at the Gaerttner Linear Accelerator (LINAC) Facility on the campus of Rensselaer Polytechnic Institute, using a 15-meter long section of the facility's neutron-beam line.

Nuclear warheads have a couple of characteristics that are central to the experiment. They tend to use particular isotopes of plutonium—varieties of the element that have different numbers of neutrons. And nuclear warheads have a distinctive spatial arrangement of materials.

The experiments consisted of sending a horizontal neutron beam first through a proxy of the warhead, then through a lithium filter scrambling the information. The beam's signal was then sent to a glass detector, where a signature of the data, representing some of its key properties, was recorded. The MIT tests were performed using molybdenum and tungsten, two metals that share significant properties with plutonium and served as viable proxies for it.

The test works, first of all, because the neutron beam can identify the isotope in question.

"At the low energy range, the neutrons' interactions are extremely isotope-specific," Danagoulian says. "So you do a measurement where you have an isotopic tag, a signal which itself embeds information about the isotopes and the geometry. But you do an additional step which physically encrypts it."

That physical encryption of the neutron beam information alters some of the exact details, but still allows scientists to record a distinct signature of the object and then use it to perform object-to-object comparisons. This alteration means a country can submit to the test without divulging all the details about how its weapons are engineered.

"This encrypting filter basically covers up the intrinsic properties of the actual classified object itself," Danagoulian explains.

It would also be possible just to send the neutron beam through the warhead, record that information, and then encrypt it on a computer system. But the process of physical encryption is more secure, Danagoulian notes: "You could, in principle, do it with computers, but computers are unreliable. They can be hacked, while the laws of physics are immutable."

The MIT tests also included checks to make sure that inspectors could not reverse-engineer the process and thus deduce the weapons information countries want to keep secret.

To conduct a weapons inspection, then, a host country would present a warhead to weapons inspectors, who could run the neutron-beam test on the materials. If it passes muster, they could run the test on every other warhead intended for destruction as well, and make sure that the data signatures from those additional bombs match the signature of the original warhead.

For this reason, a country could not, say, present one real nuclear warhead to be dismantled, but bamboozle inspectors with a series of identical-looking fake weapons. And while many additional protocols would have to be arranged to make the whole process function reliably, the new method plausibly balances both disclosure and secrecy for the parties involved.

The human element

Danagoulian believes putting the new method through the testing stage has been a significant step forward for his research team.

"Simulations capture the physics, but they don't capture system instabilities," Danagoulian says. "Experiments capture the whole world."

In the future, he would like to build a smaller-scale version of the testing apparatus, one that would be just 5 meters long and could be mobile, for use at all weapons sites.

"The purpose of our work is to create these concepts, validate them, prove that they work through simulations and experiments, and then have the National Laboratories to use them in their set of verification techniques," Danagoulian says, referring to U.S. Department of Energy scientists.

Danagoulian also emphasizes the seriousness of nuclear weapons disarmament. A small cluster of several modern nuclear warheads, he notes, equals the destructive force of every armament fired in World War II, including the atomic bombs dropped on Hiroshima and Nagasaki. The U.S. and Russia possess about 13,000 nuclear weapons between them.

"The concept of nuclear war is so big that it doesn't [normally] fit in the human brain," Danagoulian says. "It's so terrifying, so horrible, that people shut it down."

In Danagoulian's case, he also emphasizes that, in his case, becoming a parent greatly increased his sense that action is needed on this issue, and helped spur the current research project.

"It put an urgency in my head," Danagoulian says. "Can I use my knowledge and my skill and my training in physics to do something for society and for my children? This is the human aspect of the work."

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T. rex really could crush a car in its jaws, without damaging its own skull

The Tyrannosaurus rex had the strongest bite of any known land animal – extinct or otherwise.

The king of the dinosaurs was capable of biting through solid bone, but paleontologists had long been baffled as to how it accomplished this feat without breaking its own skull.

In a new study published in the journal The Anatomical Record, researchers found that the T. rex had a rigid skull, like those of modern-day crocodiles and hyenas, rather than a flexible one like birds and reptiles. That rigidity enabled the dinosaur to bite down on its hapless prey with a force upwards of 7 tons.

"The highest forces we estimated in T. rex were just shy of 64,000 Newtons, which is about 6.5 metric tonnes (7.1 tons) of force," Ian Cost, the lead author of the new study, told Business Insider.

Modern-day saltwater crocodiles, which hold the chomping record for any living animal, clamp down with a force of 16,460 newtons – only about 25 percent as strong as a T. rex's bite.

(Illustration by Zhao Chuang, courtesy of PNSO)

Scientists weren't sure whether T. rex skulls were flexible or rigid

Previously, scientists had suggested that the T. rex's roughly 6-foot-long (1.8-metre), 4-foot-tall (1.2 metre) skull had flexible joints – a characteristic called cranial kinesis.

Some creatures need to have parts of their skull moving different directions at once, and independently of their jaws. Snakes that swallow animals whole, or birds that have to nibble awkwardly-shaped foods, benefit from having a mobile skull.

Paleontologists first hypothesised that T. rex might also have benefited from mobile joints, moving its skull bones around to help bite with full force.

But Cost said that thinking didn't align with what scientists observed in modern-day predators like crocodiles and hyenas, which leverage the greatest bite forces of any animals alive today. Crocs' skulls are very rigid, with little to no cranial kinesis.

So Cost's group modelled how parrots' and geckos' skulls and jaws – two animals with mobile skulls – worked, and then applied those movements to a T. rex skull.

"What we found was that the skull of T. rex actually does not react well to being moved around and prefers to not move," Cost said.

According to Casey Holliday, a co-author of the study, there's a trade-off between movement and stability when a creature bites down with a lot of force.

"Birds and lizards have more movement but less stability," he said in a press release.

Less bite stability and range of motion limits the amount of bite force an animal can muster.

3D map of T. rex skull showing muscle activation. (Courtesy of Eric Stann/University of Missouri)

T. rex jaws could crush a car, as the Hollywood monster does in Jurassic Park

Mark Norell, a curator at the American Museum of Natural History, has described the T. rex as "a head hunter", since the predator had the rare ability to bite through solid bone and digest it.

Paleontologists know this from the dinosaur's fossilized poop; they have discovered T. rex faeces containing tiny chunks of bone eroded by stomach acid.

According to Cost, a rigid skull enabled the T. rex to bite through bone. That's how the dinosaur was "capable of producing enough force to crush some cars, but maybe not every car."

He added that funelling the T. rex's 7.1 tons of bite force "through a tooth or two at impact results in incredible pounds per square inch of pressure that could puncture-crush many vehicles, Jeep tires included."

In the 1993 Hollywood blockbuster, Jurassic Park, a T. rex escapes its paddock and attacks two Jeeps that have broken down nearby. The predator, hoping to nibble on two kids trapped inside the car, flips one Jeep upside down and proceeds to bite into the vehicle's undercarriage, puncturing a tire.

But the T. rex wasn't the only Cretaceous-era dinosaur to have an immobile skull, Holliday told Business Insider.

The Triceratops and Ankylosaurs also had fixed, akinetic skulls. Plus, some close relatives of the T. rex, including Oviraptors and Therizinosaurs, don't have the features that suggest they had flexible skulls, either.

Key features of a stiff T. rex skull. (University of Missouri)

Was the T. rex was a hunter, scavenger, or both?

According to experts at the American Museum of Natural History, the T. rex was a cannibal. But scientists don't know whether the dinosaurs killed one another or just ate T. rexes that were already dead.

When it comes to the dinosaur's other dietary preferences, arguments persist about whether the dinosaur was a hunter or a scavenger.

"A bulk of the evidence points to T. rex being a predator, not a scavenger," Gregory Erickson, a paleontologist from Florida State University, previously told Business Insider. "It was a hunter, day in and day out."

Cost said his study results, which indicate the T. rex's skull handled prey in a similar way to a hyena's, could shed some light on the debate.

"Hyenas, we know, are both hunters and scavengers," he said. "I think, if anything, that T. rex was both a hunter and an opportunistic scavenger."

This article was originally published by Business Insider.

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The world's most freakishly advanced robot dog is now for sale

We've watched the Spot robot quadruped grow up and evolve, from its earliest days as a larger, more cumbersome beast to a carefully refined machine capable of pulling trucks. Now maker Boston Dynamics is putting the robo-dog on sale.

The idea is not to provide a friendly pet that curls up in front of the fire each evening, though. Spot is designed for industrial use, whether that's carrying goods through a warehouse or inspecting a remote site that human operators would find it difficult to get to.

With that in mind, you can't just put down your cash and walk away with a Spot. Instead, Boston Dynamics will lease the Spot bot to companies with genuine uses for it: prices vary and are on request, but think in the tens of thousands of US dollars.

(Boston Dynamics)

"A nimble robot that climbs stairs and traverses rough terrain with unprecedented ease, yet is small enough to use indoors," is the description on the Boston Dynamics sales page.

"Built to be a rugged and customisable platform, Spot autonomously accomplishes your industrial sensing and remote operation needs."

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For your money you get a robot that can operate for 90 minutes between charges, with a maximum speed of 1.6 metres-per-second (about 3.5 miles-per-hour). It can work in temperatures of between -20°C (-4°F) and 45°C (113°F), and has 360-degree camera vision that enables it to avoid obstacles.

Spot can operate in the rain, too, and is able to carry payloads of up to 14 kilograms (that's nearly 31 pounds). Buyers can add bespoke sensors and hardware modules to Spot to adapt it for a variety of tasks.

"Early customers are already testing Spot to monitor construction sites, provide remote inspection at gas, oil and power installations, and in public safety," says Boston Dynamics.

As we know from previous demonstrations, the robot is able to adapt to a variety of tasks and is even capable of opening doors. It's capable of tackling rough and uneven terrain, using a bank of sensors and software calculations to stay steady on its feet.

(Boston Dynamics)

Let's just hope any new owners take good care of their Spots – kicking one off balance isn't recommended.

Spot has its weaknesses – it's not great at working around people at the moment, for example – but the robot has come a very long way in a short space of time. That the dog droid is now available for hire shows that Boston Dynamics is confident of its usefulness.

Quite how long it takes us to get to Judgement Day as depicted in the Terminator films remains to be seen, but for now the Spot robots are only going to be lifting loads, making inspections, and doing what their human operators tell them to.

"Their big example of the robot working in construction could pay off," computer scientist Noel Sharkey from Sheffield University in the UK told the BBC.

"They can reach places that humans find difficult, run across bricks and accompany builders carrying their loads of tools and bricks or map out districts for construction."



Join us on Facebook or Twitter for a regular update.



#Tech | https://sciencespies.com/tech/the-worlds-most-freakishly-advanced-robot-dog-is-now-for-sale/

Greek fashion firms revitalize centuries-old silk tradition

In this Tuesday, Sept. 10, 2019 photo, a worker shows a handful of silkworm cocoons used to make silk at Mouhtaridis Silkline manufacturing company in Soufli town, northeastern Greece. Greece's financial crisis nearly snuffed out the country's centuries-old silk manufacturing tradition, but the end of the crippling recession has raised demand for fashion products and silk produced by a remote border town. (AP Photo/Iliana Mier)

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At Kostas Mouhtaridis' silk factory in Soufli, the non-stop "clunk-click" of the weaving machinery is a loud but welcome sound.

The factory is a few hundred meters from the Evros River, which forms Greece's natural border with Turkey. It is one of Europe's most heavily militarized areas, patrolled constantly to deter illegal immigration into the European Union. 

Soufli, a once-booming silk factory town in Greece's remote northeastern Thrace region, saw its centuries-old tradition of silkworm rearing, weaving and dying nearly snuffed out during Greece's decade-long financial crisis. The town had already suffered a heavy blow when cheaper Chinese and Indian silk flooded the market in the 1990s. The companies that managed to survive then were later finished off during the financial crisis that erupted in 2008.

By 2012, there were only two silk makers left in the town, eking out an existence by supplying small home furnishing stores. 

Yet seven years later, Mouhtaridis has few complaints. The company founded by his father in 1977 has been revived by Greece's resurgent fashion and luxury goods industry as well as by technology that helps small-scale producers. 

In this Tuesday, Sept. 10, 2019, a silk digital printing machine operates at Silk Tsiakiris Company in Soufli, northeastern Greece. Greece's financial crisis nearly snuffed out the country's centuries-old silk manufacturing tradition, but the end of the crippling recession has raised demand for fashion products and silk produced by a remote border town. (AP Photo/Iliana Mier)

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"We used to give (silk products) to stores that took five, 10 meters (32 feet), or 50 meters (165 feet)," Mouhtaridis said, speaking at his factory, which employs 10 people. "The maximum (order) we would get was 100 meters (320 feet)."    

He now produces more than 200 times that amount annually for his largest customer.  

Silk is the staple of offerings at Zeus + Dione, a luxury Athens label that prides itself on reinventing and incorporating laboriously made elements found in traditional Greek garments onto its easy-to-wear women's line. Craftspeople were scouted out in rural areas around Greece to make it happen, as the company sought to inject glamor to dying trades that typically struggled to connect with city dwellers. 

The label's flagship store is now in a trendy shopping area in central Athens and the company's co-owner, bank executive Mareva Grabowski, is married to newly elected conservative Prime Minister Kyriakos Mitsotakis. She founded the company with her friend Dimitra Kolotoura, a former PR executive.  

In this Tuesday, Sept. 10, 2019, Giorgos Tsiakiris the owner of Silk Tsiakiris manufacturing company poses in front of a silk loom in Soufli town, northeastern Greece. Greece's financial crisis nearly snuffed out the country's centuries-old silk manufacturing tradition, but the end of the crippling recession has raised demand for fashion products and silk produced by a remote border town. (AP Photo/Iliana Mier)

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Kolotoura remembers walking into Mouhtaridis' silk factory as her company was just starting out seven years ago. He was skeptical when asked for 20 meters (65 feet) of 'spathoto'—an embossed silk that has become the firm's signature fabric. 

"We said: 'Let's start the engines! We are going to produce, we are going to weave, we are going to create new fabrics,'" Kolotoura says. "And we're going to experiment." 

The twist on tradition caught the attention of the fashion world and orders from overseas snowballed. Silk shirts and caftans made from spathoto and Amalia-motif fabric types can be found on sale in Los Angeles, Paris, London and elsewhere.  

Soufli's other main silk maker, Giorgos Tsiakiris, found an alternate route to survival, giving up weaving to focus on printing. When the future of the family enterprise seemed uncertain, he bet the business on expensive digital technology.

In this Wednesday, Sept. 4, 2019 photo, a seamstress works on a piece of white silk at Zeus+Dione atelier in Athens. Greece's financial crisis nearly snuffed out the country's centuries-old silk manufacturing tradition, but the end of the crippling recession has raised demand for fashion products and silk produced by a remote border town. (AP Photo/Iliana Mier)

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The bet is paying off. Replacing traditional dying with a computerized system and buying room-sized printing machines revolutionized his operation, allowing him to provide customized designs requested by fashion houses all over Europe, among them the Greek label Parthenis.     

Orsalia Parthenis took over the company from her parents, renewing a relationship with the silk factory that went back to the 1970s. 

Soufli silk was "part of my growing up," she says, noting that she always found creative ways to include it in her collections. 

"Soufli had focused mostly on traditional furnishing fabrics, things you'd use for curtains or tablecloths," she says, adding that instead she chose to use those fabrics for dresses, shorts and jackets.

 When she found out that Tsiakiris was printing silk in 2006, Parthenis jumped at the chance to reach out to graphic designers and created a silk caftan line.

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  In this Wednesday, Sept. 4, 2019 photo designer Lydia Vousvouni of fashion firm Zeus+Dione works at the firms' atelier in Athens. Greece's financial crisis nearly snuffed out the country's centuries-old silk manufacturing tradition, but the end of the crippling recession has raised demand for fashion products and silk produced by a remote border town. (AP Photo/Iliana Mier)
  

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  In this Wednesday, Sept. 4, 2019 photo, a seamstress works on a piece of white silk at Zeus+Dione atelier in Athens. Greece's financial crisis nearly snuffed out the country's centuries-old silk manufacturing tradition, but the end of the crippling recession has raised demand for fashion products and silk produced by a remote border town. (AP Photo/Iliana Mier)
  

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"They invested in machines to do more printing and it wasn't just the weaving part," she says. "Technology is what revived the industry."

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Greek fashion firms revitalize centuries-old silk tradition (2019, September 29)
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