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NASA: Ion thruster breaks power, propulsion records

© Global Look Press
How to get to Mars...
NASA's newest ion thruster has broken previous records of generating maximum power and propulsion in its latest test, suggesting the technology may become the future of deep space exploration.

The X3 thruster is being developed by researchers at the University of Michigan in collaboration with the US Air Force and NASA. The group has been working on the technology since 2009. They first developed a two-channel thruster, the X2, before the more powerful X3 was created.

The X3 thruster team said it broke records of generating maximum power output during recent testing at the Glenn Research Center of NASA in Ohio. Project lead Alec Gallimore said the thruster generated 5.4 N of thrust, the highest value of thrust recorded using a plasma thruster.

"We have shown that X3 can operate at over 100 kW of power," Gallimore told Space.com. "It operated at a huge range of power from 5 kW to 102 kW, with electrical current of up to 260 amperes. It generated 5.4 Newtons of thrust, which is the highest level of thrust achieved by any plasma thruster to date."

The X3 thruster is a Hall thruster, a type of system that uses a stream of ions to propel a spacecraft and expels plasma (a cloud of charged particles) to generate thrust. This allows for greater speeds than a traditional chemical propulsion rocket, and greater efficiency, as they require less propellant and can go about 10 times further on the same amount of fuel. "You can think of electric propulsion as having 10 times the miles per gallon compared to chemical propulsion," Gallimore said.

Galaxy

Scientists witness of gravitational waves and light from colliding of two neutron stars

© NSF LIGO Sonoma State University / A. Simonnet
A rendering of a neutron star merger
The team of scientists from the LIGO and Virgo observatories have confirmed they witnessed both gravitational waves and light coming from the collision of two neutron stars, definitively proving Einstein's General Theory of Relativity.


Hundreds of scientists from 70 observatories on all seven continents - as well as an additional seven space-based laboratories - combined their resources and expertise to analyze the signal detected on August 17 this year.

"As these neutron stars spiraled together, they emitted gravitational waves that were detectable for about 100 seconds; when they collided, a flash of light in the form of gamma rays was emitted and seen on Earth about two seconds after the gravitational waves," the researchers wrote in a press release.


The scientific community, using some of the most sensitive machines ever built by humankind, managed to determine that the two dense, dead stars were 200 miles apart before they merged just 100 seconds later, producing ripples in the fabric of space time.

"It is tremendously exciting to experience a rare event that transforms our understanding of the workings of the universe,"says France A. Córdova, director of the National Science Foundation (NSF), which funds LIGO.

Comment: See also: Gravitational Waves: Einstein's Elusive Children


Magnify

Herbicides & plant pathology: Cornell University study shows glyphosate damages soil-friendly bacteria

Cornell University researchers have found an agricultural conflict: negative consequences of the weed-killing herbicide glyphosate on Pseudomonas, a soil-friendly bacteria, they announced last week.

As farmers battle in their above-ground war on weeds using glyphosate-based herbicides, they may inadvertently create underground casualties - unintentionally attacking the beneficial bacteria that help crops guard against enemy fungus.

Comment: Un-Earthed: Is Monsanto's glyphosate destroying the soil?
It takes approximately 1,000 years for the earth to produce (on its own) a 2.5 inch thick layer of fertile soil. And yet, it may take only a single application of Roundup to irreversibly alter the microbial populations within the soil -- much in the same way that a single round of antibiotics may seriously and irreversibly alter your gut flora for the rest of your life.



Info

Engineers develop a programmable "camouflaging" material

© Roger Hanlon
Sepia apama (giant Australian cuttlefish) expressing its papillae for camouflage purposes.
Woods Hole, Mass.-For the octopus and cuttlefish, instantaneously changing their skin color and pattern to disappear into the environment is just part of their camouflage prowess. These animals can also swiftly and reversibly morph their skin into a textured, 3D surface, giving the animal a ragged outline that mimics seaweed, coral, or other objects it detects and uses for camouflage.

This week, engineers at Cornell University report on their invention of stretchable surfaces with programmable 3D texture morphing, a synthetic "camouflaging skin" inspired by studying and modeling the real thing in octopus and cuttlefish. The engineers, along with collaborator and cephalopod biologist Roger Hanlon of the Marine Biological Laboratory (MBL), Woods Hole, report on their controllable soft actuator in the October 13 issue of Science.

Led by James Pikul and Rob Shepherd, the team's pneumatically activated material takes a cue from the 3D bumps, or papillae, that cephalopods can express in one-fifth of a second for camouflage, and then retract to swim away with minimal hydrodynamic drag. (See video below of live Octopus rebescens expressing its skin papillae.)

"Lots of animals have papillae, but they can't extend and retract them instantaneously as octopus and cuttlefish do," says Hanlon, who is the leading expert on cephalopod dynamic camouflage. "These are soft-bodied molluscs without a shell; their primary defense is their morphing skin."

Galaxy

Observatory in Argentina detects extragalactic cosmic rays reaching Earth, and will help in locating their source

© A. Chantelauze, S. Staffi, L. Bret
Fifty years ago, scientists discovered that the Earth is occasionally hit by cosmic rays of enormous energies. Since then, they have argued about the source of those ultra-high energy cosmic rays - whether they came from our galaxy or outside the Milky Way.

The answer is a galaxy or galaxies far, far away, according to a report published Sept. 22 in Science by the Pierre Auger Collaboration. The internationally run observatory in Argentina, co-founded by the late University of Chicago Nobel laureate James Cronin, has been collecting data on such cosmic rays for a more than a decade.

The collaboration found that the rate of such cosmic particles, whose energies are a million times greater than that of the protons accelerated in the Large Hadron Collider, is about six percent greater from one side of the sky than the other, in a direction where the distribution of galaxies is relatively high.

Telescope

Largest digital survey of the visible Universe released by Pan-STARRS project astronomers

© Danny Farrow
Pan-STARRS1 Science Consortium and Max Planck Institute for Extraterrestial Physics
The world's largest digital survey of the visible Universe, mapping billions of stars and galaxies, has been publicly released.

The data has been made available by the international Pan-STARRS project, which includes scientists from Queen's University Belfast, who have predicted that it will lead to new discoveries about the Universe.

Astronomers and cosmologists used a 1.8-metre telescope at the summit of Haleakalā, on Maui, Hawaii, to repeatedly image three quarters of the visible sky over four years.

Microscope 1

New study suggests last common ancestor of humans and apes was much smaller than previously thought - about the size of a gibbon


Our last common ancestor was swinging through the trees like a gibbon seven million years ago, new research has found. This means it was much smaller and nimbler than previously thought, giving scientists a fresh view of the dawn of human evolution
New research suggests that the last common ancestor of apes-including great apes and humans-was much smaller than previously thought, about the size of a gibbon. The findings, published today in the journal Nature Communications, are fundamental to understanding the evolution of the human family tree.

"Body size directly affects how an animal relates to its environment, and no trait has a wider range of biological implications," said lead author Mark Grabowski, a visiting assistant professor at the Eberhard Karls University of Tübingen in Germany who conducted the work while he was a postdoctoral fellow in the American Museum of Natural History's Division of Anthropology. "However, little is known about the size of the last common ancestor of humans and all living apes. This omission is startling because numerous paleobiological hypotheses depend on body size estimates at and prior to the root of our lineage."

Among living primates, humans are most closely related to apes, which include the lesser apes (gibbons) and the great apes (chimpanzees, gorillas, and orangutans). These "hominoids" emerged and diversified during the Miocene, between about 23 million to 5 million years ago. Because fossils are so scarce, researchers do not know what the last common ancestors of living apes and humans looked like or where they originated.

Light Saber

Researchers discover secret of perovskite crystal's strong photoluminescence

© De Bastiani
A little-studied member of the perovskite family of materials could find use in a range of electronic devices, after researchers at KAUST discovered the secret of its strong photoluminescence.

Perovskites are a wide group of materials that are known to have remarkable optical and electronic properties. Perovskites with the general formula ABX3, and particularly the perovskite methylammonium lead trihalide, have attracted almost all the research attention thanks to their great promise as low-cost, high-efficiency solar cell materials.

Other members of the perovskite family and perovskite derivatives are also worthy research subjects, says Michele De Bastiani, a postdoctoral researcher in Osman Bakr's group at KAUST.

De Bastiani and his colleagues have been testing Cs4PbBr6, a perovskite of the A4BX6 branch of the family. This material is noted for its strong photoluminescence-the ability to absorb light at one wavelength and re-emit it at another.

The material's potential applications include color-converting coatings on LED light bulbs, lasers and photodetectors. But to be able to fine-tune the material's optoelectric properties for each application, researchers need to solve the mystery of why the perovskite photoluminesces so strongly.

Beaker

New technology can prevent GM organisms from breeding with their natural counterparts

A major obstacle to applying genetic engineering to benefit humans and the environment is the risk that organisms whose genes have been altered might produce offspring with their natural counterparts, releasing the novel genes into the wild. Now, researchers from the University of Minnesota's BioTechnology Institute have developed a promising way to prevent such interbreeding. The approach, called "synthetic incompatibility," effectively makes engineered organisms a separate species unable to produce viable offspring with their wild or domesticated relatives.


Comment: Will this new species be able breed with others of it's kind?


Synthetic incompatibility has applications in controlling or eradicating invasive species, crop pests and disease-carrying insects as well as preventing altered genes from escaping from genetically modified crops into other plant populations. The results were published online today in the journal Nature Communications.

The technology uses a new class of molecular tools called "programmable transcription factors" that make it possible to control which genes are turned on and which genes are turned off in an organism. If an engineered organism mates with a wild counterpart, the transcription factors render the offspring unable to survive by activating genes that cause their cells to die.

"This approach is particularly valuable because we do not introduce any toxic genes," said Maciej Maselko, a postdoctoral scholar from Smanski's lab who performed the work. "The genetic incompatibility results from genes already in the organism being turned on at the wrong place or time."

Question

Quantum physicists say that living in a matrix is impossible

© REUTERS/ Kacper Pempel
It's a question that philosophers have been asking since the dawn of philosophy itself: What's real? Is the world as we perceive it really the world? And how can we know one way or another?

The latest version of this age-old conundrum, popularized in the 1999 sci-fi film "The Matrix," puts things in modern technological terms: Could reality be nothing more than a computer simulation?

This is, technically, merely a theoretical question. No computer around today has the computing power to simulate the entire universe, not even close. But could such a super-super-supercomputer even be possible? Might you be unknowingly lying in a gel-filled pod somewhere with circuits in your head, while an ultra-powerful artificial intelligence feeds off the electrical pulses surging between neurons in your brain?

Thankfully, the plot of "The Matrix" is not only implausible, it's actually impossible. At least, that's according to a pair of quantum physicists, Zohar Ringel and Dmitry Kovrizhin, from the University of Oxford and the Hebrew University in Israel. They crunched the numbers and found that the computing power needed to simulate the universe all the way down to the quantum level would require a memory built from more atoms than there are in the universe itself.

Comment: Do we live in the Matrix?