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Starliner Launches But it Can't Reach the Station – Universe Today



Boeing’s Starliner crew capsule launched successfully, but a mishap prevented it from docking with the ISS. The ship is undamaged and will return and land at its designated location, according to officials. This could delay the planned crewed flight of the Starliner next summer.

Starliner launched successfully on Friday morning on an Atlas V rocket. But once it detached from the launch vehicle, something went wrong.

The capsule was supposed to maneuver itself into a trajectory towards the ISS, and to dock on Saturday. Early reviews from both NASA and Boeing—Starliner’s builder—indicated that a clock malfunction prevented the engines from firing at the correct time. Once they fired, they burned more fuel than anticipated, putting a rendezvous with the ISS out of reach.

Ground controllers couldn’t initiate the burn because at the time it was needed the spacecraft was briefly in between two other satellites, and couldn’t receive signals from the ground.

NASA says that had there been crew on board, they would have been unharmed and returned to Earth safely. But as of now, NASA Administrator Jim Bridenstine isn’t sure if this setback means there’ll be another un-crewed test flight before the eventual crewed flight.

“I’m not ruling it out,” Bridenstine said on whether the next Starliner might carry crew. Had astronauts been on board, they may have been able to take over, correct the problem and get the capsule to the space station, he said. Currently, Starliner is in a stable orbit, and will return to White Sands on Sunday.

Though Starliner didn’t make it to the ISS, NASA says that today’s launch and test flight was still a success.

“A lot of things went right today,” Bridenstine told reporters. “And this is, in fact, why we test.”

Boeing is competing with SpaceX to be the first American company to provide commercial crew capabilities to NASA. Image: Boeing

Boeing is competing with SpaceX to be the first to fly American personnel to the ISS since the Space Shuttle fleet was retired. Since July 2011, American astronauts have been travelling to the ISS on Russian Soyuz spacecraft. Those flights to the ISS are costing NASA up to $86 million US each.

It’s not clear how much of a setback this is for Boeing. SpaceX may well end up being the first American spacecraft to transport to the ISS since the shuttle fleet retired. In any case, SpaceX has had their own setbacks. One of their craft exploded last April during a test firing. But the Crew Dragon capsule has already completed one test flight to the ISS.

History is full of test flights that go wrong, and mostly we don’t remember them. Test flights are part of the business, and the fact that some tests find flaws means they’re working as intended.

“This is why we flight test, right? We’re trying to get all of the bugs removed out of the system,” said NASA’s Mike Fincke, one of the astronauts assigned to Starliner, at the briefing. “There’s always something.”

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Australian stinging tree could pave way for novel painkillers – News-Medical.Net



Australia is well known for having many of the world’s most venomous creatures, ranging from snakes, spiders, jellyfish, centipedes, fish, ticks, bees, and ants. 21 of the 25 most venomous snakes in the world are all from Australia. The country is also home to dangerous plants, like the Australian stinging tree.

Close up of the heart-shaped leaf of the most toxic of the Australian species of stinging trees Dendrocnide moroides, also known as the stinging brush, gympie stinger, moonlight plant among others. Image Credit: Victoria Tucholka / Shutterstock

Now, a team of researchers at the University of Queensland in Brisbane examined the toxins produced by two species of Australian stinging trees- the shrub-sized Gympie-Gympie (Dendrocnide moroides) and the giant Australian stinging tree (Dendrocnide excelsa).

Leaves of the fearsome giant stinging tree, Dendrocnide excelsa. Image Credit: Lakeview Images

Leaves of the fearsome giant stinging tree, Dendrocnide excelsa. Image Credit: Lakeview Images

The Gympie-Gympie stinging tree is one of the world’s most toxic plants and may cause excruciating long-lasting pain. From these plants, the researchers found a new family of toxins, which they called “gympietides” after the name of the tree. Usually, these trees are found in the Northern Rivers region of New South Wales and at the tip of the Cape York Peninsula.

“Our research on the venom of Australian stinging trees, found in the country’s northeast, shows these dangerous plants can inject unwary wanderers with chemicals much like those found in the stings of scorpions, spiders and cone snails,” the researchers said.

Long-lasting pain

The Australian stinging tree is covered with hollow needle-like hairs called trichomes, which are bolstered with silica. Like common nettles, the hairs contain toxins and substances, which can induce extreme pain.

The scientists reported that stinging trees produce extremely persistent and painful stings upon contact of their trichomes with mammalian skin. The pain typically lasts for several hours, and intermittent painful flares may occur for days and weeks.

“The Australian stinging tree species are particularly notorious for producing an excruciatingly painful sting, which unlike those of their European and North American relatives can cause symptoms that last for days or weeks,” Irina Vetter, associate professor at the UQ’s Institute for Molecular Bioscience, said.

“Like other stinging plants such as nettles, the giant stinging tree is covered in needle-like appendages called trichomes that are around five millimeters in length—the trichomes look like fine hairs, but act like hypodermic needles that inject toxins when they make contact with skin,” she added.

The team reported that the pain and stinging sensation might be tied to small-molecule neurotransmitters and inflammatory mediators. However, these compounds cannot explain the observed sensory effects.

In the study, published in the journal Science Advances, the team demonstrated that the venoms of the stinging trees contain unknown pain-inducing peptides.

Discovering gympietides

To arrive at the study findings, the team studied the stinging hairs from the giant Australian stinging tree, obtaining an extract from them. They separate them into their singular molecular contents. The substances produced extreme pain responses when they were tested in the laboratory.

The team discovered that the extract contains a small family of mini-proteins. Further, the team examined the genes that are found in the leaves of the Gympie-Gympie to find out which one could produce the toxin. From there, the team revealed molecules that can reproduce the pain response even when developed synthetically in the laboratory.

Gympietides contain an intricate three-dimensional structure maintained by links within the molecule that forms a knotted shape. Hence, the toxin is kept stable, which stays intact for a long time once it gets injected into the victim. The structure of the gympietides is similar to the toxins from the cone snail, scorpion, and spider venom, which affect ion channels in nerve cells that are known as mediators of pain.

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“The 3D structure of these gympietides is reminiscent of animal venom toxins targeting the same receptors, thus representing a remarkable case of inter-kingdom convergent evolution of animal and plant venoms,” the researchers wrote in the paper.

“Our work clarifies the molecular basis for the pain caused by these plants while enabling structure-activity and convergent evolution studies to define how ancestrally distinct peptides in venoms may elicit the same response at pain receptors,” they added.

The researchers hope that the toxins will provide new information on how pain-sensing nerves function, paving the way for the development of novel painkillers.

Journal reference:

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How to watch historic SpaceX rocket launch more Starlink satellites Friday – CNET



The Falcon 9 rocket booster that sent NASA astronauts to the International Space Station in May is scheduled to get recycled again Friday, when SpaceX plans to send 60 more Starlink satellites to orbit atop its column of fire. 

Elon Musk’s trademark reusable rocket will be making its third flight when it lifts off from Florida’s Kennedy Space Center at 10:57 a.m. PT (1:57 p.m. ET). This specific unit sent astronauts Doug Hurley and Bob Behnken to orbit in May and then launched a South Korean satellite in July. So far, SpaceX has managed to launch and land the same rocket up to six times

The launch was originally scheduled for Thursday, but it got scrubbed and pushed back a day due to a “recovery issue.” It could be that SpaceX didn’t like the look of the weather in the Atlantic where the first stage and the fairing were set to be recovered. 

One half of the nose cone, or fairing, atop the rocket has also seen two previous flights, both of them earlier Starlink missions. 

This should be a fairly routine launch. It will be the 13th Starlink mission so far, and SpaceX is ultimately planning on dozens more as it grows its broadband mega-constellation.

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SpaceX Starship prototype takes first ‘hop’


Following the launch and separation of the rocket’s second stage and payload, the first-stage booster will again return to Earth to land on a droneship in the Atlantic. 

SpaceX will stream the entire thing via the feed above, starting at about 10 minutes before launch.

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Scientists Find Efficient Way to Convert Carbon Dioxide into Ethylene | Chemistry, Materials Science –



A team of U.S. researchers has developed copper nanowires with rich surface steps to catalyze a chemical reaction that reduces carbon dioxide (CO2) emissions while generating ethylene (C2H4), an important chemical used to produce plastics, solvents, cosmetics and other important products globally.

Copper represents an effective catalyst in reducing carbon dioxide to hydrocarbons or oxygenates, but it is often plagued by a low product selectivity and limited long-term stability. Choi et al report that copper nanowires with rich surface steps exhibit a remarkably high Faradaic efficiency for ethylene that can be maintained for over 200 hours. Image credit: Choi et al, doi: 10.1038/s41929-020-00504-x.

“The idea of using copper to catalyze this reaction has been around for a long time, but the key is to accelerate the rate so it is fast enough for industrial production,” said co-lead author Professor William Goddard III, a researcher in the Department of Applied Physics and Materials Science at Caltech.

“This study shows a solid path towards that mark, with the potential to transform ethylene production into a greener industry using carbon dioxide that would otherwise end up in the atmosphere.”

Using copper to kick start the carbon dioxide reduction into ethylene reaction has suffered two strikes against it.

First, the initial chemical reaction also produced hydrogen and methane — both undesirable in industrial production.

Second, previous attempts that resulted in ethylene production did not last long, with conversion efficiency tailing off as the system continued to run.

To overcome these two hurdles, Professor Goddard III and colleagues focused on the design of the copper nanowires with highly active steps — similar to a set of stairs arranged at atomic scale.

One intriguing finding of this collaborative study is that this step pattern across the nanowires’ surfaces remained stable under the reaction conditions, contrary to general belief that these high energy features would smooth out.

This is the key to both the system’s durability and selectivity in producing ethylene, instead of other end products.

The scientists demonstrated a carbon dioxide-to-ethylene conversion rate of greater than 70%, much more efficient than previous designs, which yielded at least 10% less under the same conditions.

The new system ran for 200 hours, with little change in conversion efficiency, a major advance for copper-based catalysts.

In addition, the comprehensive understanding of the structure-function relation illustrated a new perspective to design highly active and durable carbon dioxide reduction catalyst in action.

“We are at the brink of fossil fuel exhaustion, coupled with global climate change challenges,” said co-lead author Professor Yu Huang, a researcher in the Department of Materials Science and Engineering at the University of California, Los Angeles.

“Developing materials that can efficiently turn greenhouse gases into value-added fuels and chemical feedstocks is a critical step to mitigate global warming while turning away from extracting increasingly limited fossil fuels.”

“This integrated experiment and theoretical analysis presents a sustainable path towards carbon dioxide upcycling and utilization.”

The team’s paper was published in the journal Nature Catalysis.


C. Choi et al. Highly active and stable stepped Cu surface for enhanced electrochemical CO2 reduction to C2H4. Nat Catal, published online September 7, 2020; doi: 10.1038/s41929-020-00504-x

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