Monthly Archives: July 2018

Solar

Brighter Future For Us All: High-Fidelity Images of Sun’s Atmosphere Tell The Tale

A Southwest Research Institute-led team discovered never-before-detected, fine-grained structures in the Sun’s outer atmosphere, or corona. The team imaged this critical region in detail using sophisticated software techniques and longer exposures from the COR-2 camera onboard NASA’s Solar and Terrestrial Relations Observatory-A (STEREO-A).

The Sun’s outer corona is the source of the solar wind, the stream of charged particles that flow outward from the Sun in all directions. Measured near Earth, the magnetic fields embedded within the solar wind are intertwined and complex.

“Previous images showed the outer corona as a smooth structure, but in deep space, the solar wind is turbulent and gusty,” said SwRI’s Dr. Craig DeForest, a solar physicist and lead author of “The Highly Structured Outer Corona,” an article published by Astrophysical Journal July 18, 2018.

“Using new techniques to improve image fidelity, we realized that the corona is not smooth, but structured and dynamic. Every structure that we thought we understood turns out to be made of smaller ones and to be more dynamic than we thought.”

To understand the corona, DeForest and his colleagues started with extended exposures of STEREO-A’s coronagraph images – pictures of the Sun’s atmosphere produced by a special telescope that blocks out light from the bright solar disk.

The coronagraph is sensitive enough to image the corona in great detail, but in practice its measurements are polluted by noise both from the space environment and the instrument itself. The team’s key innovation was identifying and separating out that noise, boosting the signal-to-noise ratio and revealing the outer corona in unprecedented detail.

“We couldn’t tinker with the instrument itself, so we took a software approach, squeezing out the highest quality data possible by improving the data’s signal-to-noise ratio,” DeForest said. “We developed new filtering algorithms, designed and tested to delineate the true corona from the noisy measurements.”

The algorithms filtered out light and adjusted brightness. But the most challenging obstacle is inherent: blur due to the motion of the solar wind. “This technique adjusted images not just in space, not just in time, but in a moving coordinate system,” DeForest said.

“That allowed us to correct motion blur not just by the speed of the wind, but by how rapidly features changed in the wind.”

With the resulting unprecedented view of the corona, the team made several groundbreaking discoveries. For example, coronal streamers – magnetic loops that can erupt into coronal mass ejections that send blobs of solar material into space – are far more structured than previously thought.

“What we found is that there is no such thing as a single streamer,” DeForest said. “The streamers themselves are composed of myriad fine strands that, together, average to produce a brighter feature.”

Then there’s the theoretical Alfven surface – a proposed surface, or sheet-like layer where the gradually accelerating solar wind reaches a critical speed. But that’s not what DeForest’s team observed.

“What we found is that there isn’t a clean Alfven surface,” DeForest said. “There’s a wide ‘no-man’s land’ or `Alfven zone’ where the solar wind gradually disconnects from the Sun, rather than a single clear boundary.”

And the close look at the coronal structure also raised new questions. Techniques used to estimate the speed of the solar wind revealed that the wind suddenly changes its character at a distance of around 10 solar radii, well within the conventional boundary of the corona itself.

“Some interesting physics is happening around there,” DeForest said. “We don’t know what it is yet, but we do know that it is going to be interesting.”

These first observations will provide key insight for NASA’s upcoming Parker Solar Probe, the first-ever mission to gather measurements from within the outer solar corona.

Catching Them In The Act: Hyper Fast Camera Captures Atoms In Motion

An extremely fast “electron camera” at the Department of Energy’s SLAC National Accelerator Laboratory has produced the most detailed atomic movie of the decisive point where molecules hit by light can either stay intact or break apart.

The results could lead to a better understanding of how molecules respond to light in processes that are crucial for life, like photosynthesis and vision, or that are potentially harmful, such as DNA damage from ultraviolet light.

In the study, published in Science, researchers looked at a gas whose molecules have five atoms each. They watched in real time how light stretched the bond between two atoms in the molecules to a “point of no return,” sending the molecules on a path that either further separated the atoms and cleaved the bond or caused the atoms to vibrate while preserving the bond.

“The starting and end points of a chemical reaction are often obvious, but it’s much more challenging to take snapshots of the rapid reaction steps in between,” said postdoctoral researcher Jie Yang, the study’s lead author from SLAC’s Accelerator Directorate and the Stanford PULSE Institute.

“The crossroads where a molecule can do one thing or another are an important factor in determining the outcome of a reaction. Now we’ve been able to observe directly for the first time how the atomic nuclei of a molecule rearrange at such an intersection.”

Co-author Todd Martinez, a professor at SLAC and Stanford University and an investigator at PULSE, said, “The system we studied is a paradigm for the much more complex light-driven reactions in nature.” For example, the absorption of ultraviolet light can cause damage to DNA, but other mechanisms turn the light’s energy into molecular vibrations and minimize the harmful effect.

Ultra-High-Speed Snapshots of Atoms in Motion
The first steps in light-driven reactions are extremely fast. Molecules absorb light almost instantaneously, leading to a rapid rearrangement of their electrons and atomic nuclei. To see what happens in real time, researchers need ultra-high-speed cameras that can “freeze” motions occurring within femtoseconds, or millionths of a billionth of a second.

The camera used in the study was an instrument for ultrafast electron diffraction (UED), in which a high-energy beam of electrons probes the interior of a sample, generating snapshots of its atomic architecture at different points in time during a chemical reaction. Strung together, these snapshots turn into a movie of the speedy atomic motions.

At SLAC, the researchers flashed laser light into a gas of trifluoroiodomethane molecules and observed over the course of hundreds of femtoseconds how bonds between carbon and iodine atoms elongated to a point at which the bond either broke, splitting off iodine from the molecules, or contracted, setting off vibrations of the atoms along the bond.

“UED was absolutely crucial to seeing that point during the reaction,” said physicist Xijie Wang, head of SLAC’s UED program and the study’s principal investigator. “Other methods either don’t detect nuclear motions directly or haven’t reached the resolution necessary to make this kind of observation in gases.”

Mapping Energy Landscapes of Chemical Reactions
The observation is in agreement with calculations that provide a deeper understanding of what happens during the reaction.

The laser light “energizes” the molecules, elevating them from a low-energy ground state to a higher-energy excited state (see image below). Molecular states like these can be described by energy landscapes, with mountains of more energy and valleys of less energy. Like a golf ball rolling on a curved putting green, the molecules can follow reaction paths on these surfaces.

When the landscapes of different molecular states intersect, the reaction can proceed in several directions. Chemists call this point a conical intersection.

In fact, molecules at conical intersections exist in several states at once – an oddity rooted in the fact that molecules are tiny quantum systems, said co-author Xiaolei Zhu, a postdoctoral researcher at PULSE and Stanford. “We can predict this behavior in computer simulations,” he said. “Now we’ve also directly seen that the molecules behave exactly that way in the experiment.”

The team is now planning the next steps. “We’re continuing to develop the UED method so that we can look at similar processes in liquids,” Wang said. “This will bring us even closer to understanding light-driven chemical reactions in biological environments.”

From Where They’re Sitting: China’s Trade Surplus With USA Swells in June 

Seeing it from a foreign perspective.

China’s surplus with the United States hit a record last month, data showed Friday, adding to brewing tensions between the economic superpowers as they stand on the brink of an all-out trade war that Beijing warned would have a “negative impact” globally.

The figures come after the two sides exchanged tit-for-tat tariffs on billions of dollars worth of goods and President Donald Trump threatened to up the ante with measures on a further $200 billion of Chinese imports.

Beijing said China’s surplus with the US hit an all-time high $28.97 billion last month, while exports to the country hit a record $42.62 billion.

Over the first six months of the year the surplus climbed to $133.8 billion, up 13.8 percent from last year, as total two-way trade continued to expand despite the face-off.

The imbalance is at the heart of Trump’s anger at what he describes as Beijing’s unfair trade practices that are hurting American companies and destroying jobs.

But in a statement from its commerce ministry Thursday, China blamed those problems on the USA, saying the imbalance was “overestimated” and caused by America’s own “domestic structural problems”.

China’s overall surplus continued to shrink, falling 24.5 percent on-year for the first six months, the data showed, with customs saying it has shrunk for the past eight quarters.

Last Friday, Trump rolled out 25 percent tariffs on $34 billion of Chinese goods, prompting Beijing to accuse Washington of launching the “largest trade war” in economic history and immediately match the US tariffs dollar for dollar.

“This trade dispute will definitely have an impact on China-US trade and will have a very negative impact on global trade,” said customs administration spokesman Huang Songping at a briefing Friday.

— A spiralling battle —

China’s commerce ministry has said the two sides are not discussing restarting trade negotiations, and renewed its pledge to “strike back” against Washington’s latest threat to slap $200 billion of Chinese imports with new 10 percent taxes.

The threat hammered global markets, especially as fears mount that Trump’s decision to pick fights with other key allies such as Canada and the European Union could fuel an all-out global trade war.

The spiralling battle with Beijing shows no signs of cooling down, and observers warn the impact will begin to hurt soon as China’s economy struggles with slowing growth — and just as leaders try to battle a worryingly large debt mountain.

“Looking ahead, export growth will cool in the coming months as US tariffs start to bite alongside a broader softening in global demand,” said Julian Evans-Pritchard of Capital Economics.

Beijing will back away from its war on debt and roll out policy easing measures, predicted China economist at Nomura investment bank Ting Lu, as it faces potential trade war fallout and a domestic slowdown proving to be worse than expected.

“We expect (economic) growth to slow noticeably” in the second half of the year, he said in a research note.

China’s total exports rose 11.3 percent year-on-year in June, beating a Bloomberg News forecast of 9.5 percent, while imports increased 14.1 percent, below the forecast 21.3 percent.

— Disrupting trade —

China’s June export upswing may have been caused by exporters shipping their goods early to beat the scheduled tariffs, analysts say, with the trade fight expected to further impact such data in coming months.

Beijing has instructed companies to look for imports beyond the US, and this week an official at China’s largest grain trader said it hoped to diversify away from US soybeans to those grown in South America and Eastern Europe.

The US has “no respect for rules of international law and international order,” said assistant foreign minister Zhang Jun on Friday, adding that China would step up cooperation with other developing nations like the BRICS grouping.

“This is the way for us to respond to the challenges of unilateralism and trade protectionism,” said Zhang.

Trump meet with May

Trump Attacks US ‘foolishness’ Heading Into Putin Powwow

President Donald Trump headed into his first summit with Vladimir Putin on Monday determined to forge a personal bond with the Kremlin chief and adamant that only “stupidity” by prior administrations had brought US-Russian ties to their present low.

Hours before the Helsinki summit, Trump was asked if he would press Putin over Russia’s alleged manipulation of the 2016 election that brought the mercurial property tycoon to power. He said only: “We’ll do just fine.”

Democrats had called for the summit’s cancellation after new revelations surrounding the election meddling. But Trump has insisted it is “a good thing to meet”, as he attempts to replicate with Putin the sort of personal rapport he proclaims with the autocratic leaders of China and North Korea.

If his instinct proves right and the pair find common ground, then the summit may take the heat out of some of the world’s most dangerous conflicts including Syria.

But the Washington-Moscow rivalry has rarely been more bitter, and there are many points of friction that could yet spoil Trump’s hoped-for friendship.

Trump began the day’s talks by meeting Finland’s President Sauli Niinisto, who has loaned his harbour-front palace for the occasion. But first he took a moment to fire a Twitter broadside at his domestic opponents, blaming the diplomatic chill on the investigation into Russian election meddling.

“Our relationship with Russia has NEVER been worse thanks to many years of U.S. foolishness and stupidity and now, the Rigged Witch Hunt!” Trump tweeted.

After a stormy NATO summit in Brussels last week, Trump was accused by critics of cosying up to Putin while undermining the alliance.

But, over breakfast with Niinisto, he insisted NATO “has never been stronger” and “never been more together” thanks to his insistence on all allies paying their fair share.

With Washington and Moscow at loggerheads over Ukraine, Iran and trade tariffs as well as Syria, even Trump has cautioned that he is not approaching the Putin summit “with high expectations”.

The 72-year-old brash billionaire has been president for 18 months, while the former KGB officer, 65, has run Russia for the past 18 years.

In an interview with CBS News that aired before he touched down in Helsinki, Trump admitted that Russia remains a foe, but he put Moscow on a par with China and the European Union as economic and diplomatic rivals.

The Kremlin has also played down hopes that the odd couple will emerge from their first formal one-on-one summit with a breakthrough.

Putin, who played host at the World Cup final in Moscow on Sunday and was due to arrive in Finland later Monday, has remained terse in the run-up to the summit.

On Friday his adviser Yuri Ushakov also played down expectations, saying: “The state of bilateral relations is very bad…. We have to start to set them right.”

– Giving up ground? –

Indeed, after the bad-tempered NATO summit and a contentious trip by Trump to Britain, anxious European leaders may be relieved if not much comes out of the Helsinki meeting.

Those leaders are already fuming over Trump’s imposition of trade tariffs on various countries, including Russia.

European Union President Donald Tusk called on the United States, China and Russia to work together to cool the global trade tensions, warning that they could spiral into violent “conflict and chaos”.

For their part, protesters have been on the streets of Helsinki to denounce the policies of both Trump and Putin. Greenpeace draped a giant banner down a church tower urging: “Warm our hearts not our planet.”

Trump is also under pressure from Britain to press Putin over the nerve agent poisoning of four people in the city of Salisbury.

One of the victims, Dawn Sturgess, has died and her 19-year-old son Ewan Hope told the Sunday Mirror newspaper: “We need to get justice for my mum.”

– Extradition demand? –

Many fear that Trump — in his eagerness to prove that he was right to seek the summit with Putin despite US political opposition — may give up too much ground.

Ahead of the talks, Trump has refused to personally commit to the US refusal to recognise Russia’s annexation of Crimea, leaving open the possibility of a climb-down linked to a promise by Putin to somehow rein in Iranian influence in Syria.

If Washington were to de facto accept Russia’s 2014 land-grab, this would break with decades of US policy and send tremors through NATO’s exposed eastern flank.

And there will be outrage at home if Trump does not confront Putin over the election scandal.

But the US leader would not say whether he would demand the extradition of 12 Russian intelligence officers who were indicted last week by US special prosecutor Robert Mueller, for allegedly hacking Trump rival Hillary Clinton’s computer server.

First Space Tourist Flights Could Come In 2019

The two companies leading the pack in the pursuit of space tourism say they are just months away from their first out-of-this-world passenger flights — though neither has set a firm date.

Virgin Galactic, founded by British billionaire Richard Branson, and Blue Origin, by Amazon creator Jeff Bezos, are racing to be the first to finish their tests — with both companies using radically different technology.

– Moments of weightlessness –

Neither Virgin nor Blue Origin’s passengers will find themselves orbiting the Earth: instead, their weightless experience will last just minutes. It’s an offering far different from the first space tourists, who paid tens of millions of dollars to travel to the International Space Station (ISS) in the 2000s.

Having paid for a much cheaper ticket — costing $250,000 with Virgin, as yet unknown with Blue Origin — the new round of space tourists will be propelled dozens of miles into the atmosphere, before coming back down to Earth. By comparison, the ISS is in orbit 250 miles (400 kilometers) from our planet.

The goal is to approach or pass through the imaginary line marking where space begins — either the Karman line, at 100 kilometers or 62 miles, or the 50-mile boundary recognized by the US Air Force.

At this altitude, the sky looks dark and the curvature of the earth can be seen clearly.

– Virgin Galactic –

With Virgin Galactic, six passengers and two pilots are boarded onto SpaceShipTwo VSS Unity, which resembles a private jet.

The VSS Unity will be attached to a carrier spacecraft — the WhiteKnightTwo — from which it will then detach at around 49,000 feet (15,000 meters.) Once released, the spaceship will fire up its rocket, and head for the sky.

Then, the passengers will float in zero-gravity for several minutes, before coming back to Earth.

The descent is slowed down by a “feathering” system that sees the spacecraft’s tail pivot, as if arching, before returning to normal and gliding to land at Virgin’s “spaceport” in the New Mexico desert.

In total, the mission lasts between 90 minutes and two hours. During a May 29 test in California’s Mojave desert, the spaceship reached an altitude of 21 miles, heading for space.

In October 2014, the Virgin spaceship broke down in flight due to a piloting error, killing one of two pilots on board. The tests later resumed with a new craft.

The company has now also reached a deal to open a second “spaceport” at Italy’s Tarente-Grottaglie airport, in the south of the country.

Branson in May told BBC Radio 4 that he hoped to himself be one of the first passengers in the next 12 months. About 650 people make up the rest of the waiting list, Virgin told AFP.

– Blue Origin –

Blue Origin, meanwhile, has developed a system closer to the traditional rocket: the New Shepard.

On this journey, six passengers take their place in a “capsule” fixed to the top of a 60-foot-long rocket. After launching, it detaches and continues its trajectory several miles toward the sky. During an April 29 test, the capsule made it 66 miles.

After a few minutes of weightlessness, during which passengers can take in the view through large windows, the capsule gradually falls back to earth with three large parachutes and retrorockets used to slow the spacecraft.

From take-off to landing, the flight took 10 minutes during the latest test.

Until now, tests have only been carried out using dummies at Blue Origin’s West Texas site.

Company officials were recently quoted as saying the first tests with Blue Origin astronauts would take place “at the end of this year,” with tickets for the public expected to go on sale in 2019.

But in comments to AFP Friday, the company struck a more cautious note.

“We have not set ticket pricing and have had no serious discussions inside of Blue on the topic,” the firm said. “We have a flight test schedule and schedules of those types always have uncertainties and contingencies. Anyone predicting dates is guessing.”

– What’s next? –

SpaceX and Boeing are developing their own capsules to transport NASA astronauts, most likely in 2020, after delays — a significant investment that the companies will likely make up for by offering private passenger flights.

“If you’re looking to go to space, you’ll have quadruple the menu of options that you ever had before,” Phil Larson, assistant dean at the University of Colorado, Boulder’s College of Engineering and Applied Science, told AFP.

Longer term, the Russian firm that manufactures Soyuz rockets is studying the possibility of taking tourists back to the ISS. And a US start-up called Orion Span announced earlier this year it hopes to place a luxury space hotel into orbit within a few years — but the project is still in its early stages.