SpaceJibe

September 19, 2016

NASA is building the largest rocket of all time for a 2018 launch

Filed under: Cool, Inner Solar System, Mars, Military, Space Exploration, Space Ships — bferrari @ 8:54 am
Artist's rendering of a blueprint of the completed Space Launch System. (NASA/MSFC)

Artist’s rendering of a blueprint of the completed Space Launch System. (NASA/MSFC)

NASA has worked on some inspiring interplanetary projects in the last few years, but few have been as ambitious as the simply-named Space Launch System, a new rocket that will be the largest ever built at 384 feet tall, surpassing even the mighty Saturn V(363 feet), the rocket that took humanity to the moon. It will also be more powerful, with20 percent more thrust using liquid hydrogen and oxygen as fuel. Last week, NASA announced that the Space Launch System, SLS for short, is on track to perform its first unmanned test launch in 2018. The larger goal is to carry humans into orbit around an asteroid, and then to Mars by the 2030s. After that, NASA says the rocket could be used to reach Saturn and Jupiter.

At the moment, even getting off the ground would be progress: since the retirement of the Space Shuttle in 2011, NASA has been left without any domestic capability to launch American astronauts into space; instead it has been purchasing rides for them aboard Russian Soyuz spacecraft at high cost. While SpaceX and other private companies are working furiously to provide their own human passenger spacecraft for travel into Earth’s orbit, NASA wants to go even further. The agency has begun testing models of the SLSand initial construction of some the major components. It says the first test flight will have an initial cost of $7 billion. The SLS will also be reusing some leftover parts from the inventory of the retired Space Shuttle, including its engines.

However, as with many large NASA projects, the SLS has already been delayed from an initial flight in 2017, and lawmakers in Congress, who must approve NASA’s budget, areconcerned about further delays and cost overruns. Whether NASA is able to keep the project on track remains to be seen, but at the moment, it’s all systems go. Check out the progress and promise in photos and conceptual illustrations below.

NASA engineers used a 67.5-inch model to test how environmental factors including wind and water would affect the rocket on the launchpad. (Credit: NASA/LaRC)

NASA engineers used a 67.5-inch model to test how environmental factors including wind and water would affect the rocket on the launchpad. (Credit: NASA/LaRC)

 

Artist's rendering of the Space Launch System sitting on the launchpad at Kennedy Space Center in Cape Canaveral, Florida. (NASA/MSFC)

Artist’s rendering of the Space Launch System sitting on the launchpad at Kennedy Space Center in Cape Canaveral, Florida. (NASA/MSFC)

More awesome images here:

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August 24, 2016

‘Second Earth’ exoplanet found right under our noses – just four light years away

Filed under: Cool, Cosmology, Exoplanets, Extraterrestrial Life, Life, Outer Solar System — bferrari @ 2:29 pm

Proxima b is a likely target for Starshot project

 

Artist's impression of Proxima b and Proxima Centauri [Photo credit: ESO/M. Kornmesser]

Artist’s impression of Proxima b and Proxima Centauri [Photo credit: ESO/M. Kornmesser]

Rumours that a terrestrial planet orbiting Proxima Centauri – the Sun’s closest neighbour – may be Earth-like have been confirmed today in a paper published in Nature.

The possibility that extraterrestrial life may exist next door was first reported last week in Der Spiegel, a German weekly news magazine.

Excitement bubbled over and the European Southern Observatory refused to confirm or deny the rumours, as it wanted to keep the research under wraps. But it eventually gave in, and announced that all details would be revealed at the end of August.

Tantalising evidence shows the candidate planet, known as Proxima b, may be small and rocky and lies in the habitable zone around its star – just like Earth.

Proxima b’s equilibrium temperature is within the range where water may be in liquid form on its surface, the researchers believe.

It orbits around Proxima Centauri, a red-dwarf located only 4.25 light years away in the closest star system, Alpha Centauri. It’s much closer to its star than the Earth is to the Sun at 0.05 astronomical units away, so a year only lasts 11.2 days.

How Earth-like is Proxima b?

Although the signs are promising, it’s completely hypothetical that Proxima b is Earth-like, the researchers said.

Infographic compares the orbit of Proxima b around Proxima Centauri with the same region of the Solar System [Photo credit: ESO/M. Kornmesser/G. Coleman]

Infographic compares the orbit of Proxima b around Proxima Centauri with the same region of the Solar System [Photo credit: ESO/M. Kornmesser/G. Coleman]

Professor Hugh Jones, who was part of the large team analysing data from Proxima b and a physics lecturer at the University of Hertfordshire, told The Register: “Saying it’s more Earth-like than just its mass is speculative. It’s exciting because it’s the first time anybody has found a planet around the closest stars. We have been looking for ages.”

Sixteen years ago, researchers first spotted a signal that Proxima Centauri could be harbouring a planet. It took a while for confirmation because of the faint signal, Jones said.

Proxima Centauri is a faint star with a luminosity much lower than the Sun. Its surface temperature is 3,050 kelvin, as compared to the Sun’s 5,777 kelvin. Researchers used Doppler spectroscopy to measure changes in the velocity of the star caused by a gravitationally bound body that was orbiting around it.

The Doppler method is an effective way of detecting exoplanets, but it doesn’t give much information about the planet itself. Many properties, including Proxima b’s radius, are currently unknown.

Journey to Alpha Centauri

That doesn’t dampen the spirits of scientists and engineers working on the Breakthrough Starshot project, however.

Starshot was launched in April 2016 by Russian billionaire Yuri Milner and acclaimed physicist Stephen Hawking. The project aims to send tiny “nanocrafts” to the Alpha Centauri system, about 25 trillion miles away, at 15 to 20 per cent of the speed of light.

Speaking about the research, Professor Avi Loeb, Chairman of the Breakthrough Starshot advisory committee and researcher at Harvard University, told The Register: “We will celebrate this important discovery within the Starshot team.”

“The discovery of the habitable planet around the nearest star, Proxima Centauri, is strategically important for motivating the Breakthrough Starshot initiative, since it provides an obvious target for a flyby mission.

“A spacecraft equipped with a camera and various filters could take color images of the planet and infer whether it is green (harboring life as we know it), blue (with water oceans on its surface) or just brown (dry rock),” Loeb said.

The bright star is Alpha Centauri AB and Proxima Centauri is the fainter red dwarf star  [Photo credit: Digitized Sky Survey 2, Acknowledgement: Davide De Martin/Mahdi Zamani]

The bright star is Alpha Centauri AB and Proxima Centauri is the fainter red dwarf star [Photo credit: Digitized Sky Survey 2, Acknowledgement: Davide De Martin/Mahdi Zamani]

Proxima b has another property that increases its chances of harbouring life, Loeb, who was uninvolved in the research, said.

“Low-mass stars burn nuclear fuel at a slower rate, so they are more likely to live longer. Proxima Centauri is smaller than our Sun and will live about a thousand times longer. This means that any life on the planet has a longer time to develop and survive,” Loeb told The Register.

“Hence, a habitable rocky planet around Proxima would be the most natural location to where our civilization could aspire to move after the Sun will die, five billion years from now.”

The prospect of nanobots venturing to Proxima b to take photos is still very far away, and with current technology it’s still difficult to resolve Proxima b from its star. But with better telescopes and sensitive instruments being built in the next decade, the close proximity of Proxima b gives researchers their best fighting chance yet of looking out for extraterrestrial life.

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June 23, 2016

NASA reveals the X-57, its electric plane project

Filed under: Cool, Gadgets, Military, Space Ships — bferrari @ 2:57 pm

1466451753763Artist’s concept of the X-57. (NASA Langley/Advanced Concepts Lab, AMA, Inc.)

 

An electric plane project is in the works at NASA, and the new aircraft is called the X-57. It’s an initiative the space agency hopes will demonstrate that electric-powered aviation can be environmentally friendly, quiet, and quick.

Made out of a modified Italian-designed plane, the X-57 will have a skinny wing with a total of 14 battery-powered motors, and because it won’t run on gas, it won’t produce exhaust from burnt fossil fuels. NASA said that having multiple small engines means the X-57 will need less energy to cruise at a speed of 175 mph.

And while traditional fuel-burning airplanes need to cruise slower than their maximum speed to be the most fuel-efficient, the space agency says that that isn’t the case with an electric-powered plane.

Related: Solar Impulse 2 attempts fuel-free trans-Atlantic flight

The “X” designation in the plane’s name places it the tradition of experimental aircraft, with the first, the X-1, the name of the plane that broke the sound barrier in 1947 at the hands of Chuck Yeager.

“With the return of piloted X-planes to NASA’s research capabilities – which is a key part of our 10-year-long New Aviation Horizons initiative – the general aviation-sized X-57 will take the first step in opening a new era of aviation,” Charles Bolden, the NASA administrator, said in a statement.

Related: Hang glider aims to break long-distance flight record

The space agency may in fact make more than one aircraft in the program. “As many as five larger transport-scale X-planes also are planned as part of the initiative,” NASA says. The plane is also called Maxwell, named after James Clerk Maxwell, a vanguard in the study of electromagnetism.

The power of clean energy in aviation is in the spotlight lately, as the sun-powered aircraft Solar Impulse 2took off from New York’s Kennedy airport at 2:30 a.m. EDT Monday, on a daring trip across the Atlantic Ocean— the latest leg of a record-breaking solar-powered journey around the world meant to showcase the power of renewable energy.

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June 3, 2016

Did our sun steal ‘Planet 9’ from another star?

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There are eight planets in our solar system, and have been officially ever since Pluto was reclassified as a dwarf planet in 2006. But what if there was a ninth planet, billions of miles past Neptune?

Earlier this year, researchers from CalTech announced that they had found signs of the planet, which is referred to a “Planet 9,” through modeling and computer simulations. If a ninth planet were out there, it would be a big one— ten times the mass of Earth— and very, very far away, completing just one orbit around the sun as slowly as perhaps every 10,000 to 20,000 years.

Related: Scientists may have just found a ninth planet and it’s massive

Now, scientists from Lund University in Sweden have used computer simulations to propose a new theory about how Planet 9— if it exists— came to be a member of the solar system. They propose that it was stolen by our sun from another star about 4.5 billion years ago.

“What we were arguing was that you could create this [Planet 9] around another star, and then the sun could capture it, in a close encounter,” Alexander Mustill, a researcher in the department of astronomy and theoretical physics at Lund University, explained in a video about the theory.

Related: NASA identifies 1,284 new exoplanets, most ever announced at once

“We argue that this is how you could put this planet on a wide orbit around the sun,” he added. “You first create it around another star, and then the sun captures it.”

The researchers argue that this would make this planet an exoplanet, which is the term scientists use to describe planets in other star systems beyond our own. Just last month, NASA announced that they had added over 1,200 new exoplanets to the official roster, all of them discoveries from the Kepler spacecraft that had been validated through a new statistical method.

Related: Planet discovery fuels interest in mythical world of deep space

“It’s very exciting to this that there might be an extrasolar planet in our own solar system,” Mustill said.

The study proposing the new theory about Planet 9 was published online in the Monthly Notices of the Royal Astronomical Society in April.

Source

May 3, 2016

Three newly discovered Earth-sized planets may be prime spot to hunt alien life

Filed under: Cool, Exoplanets, Extraterrestrial Life, Space Exploration — bferrari @ 10:56 am
The artist’s impression provided by European Southern Observatory on May 2, 2016 shows an imagined view from the surface one of the three planets orbiting an ultracool dwarf star just 40 light-years from Earth that were discovered using the TRAPPIST telescope at ESO’s La Silla Observatory. (ESO/M. Kornmesser via AP)

The artist’s impression provided by European Southern Observatory on May 2, 2016 shows an imagined view from the surface one of the three planets orbiting an ultracool dwarf star just 40 light-years from Earth that were discovered using the TRAPPIST telescope at ESO’s La Silla Observatory. (ESO/M. Kornmesser via AP)

Astronomers searching for life beyond our solar system may need to look no farther than a little, feeble nearby star.

A Belgian-led team reported Monday that it’s discovered three Earth-sized planets orbiting an ultra-cool dwarf star less than 40 light-years away. It’s the first time planets have been found around this type of star — and it opens up new, rich territory in the search for extraterrestrial life.

Because this star is so close and so faint, astronomers can study the atmospheres of these three temperate exoplanets and, eventually, hunt for signs of possible life. They’re already making atmospheric observations, in fact, using NASA’s Spitzer Space Telescope. The Hubble Space Telescope will join in next week.

Altogether, it’s a “winning combination” for seeking chemical traces of life outside our solar system, said Massachusetts Institute of Technology researcher Julien de Wit, a co-author of the study, released by the journal Nature.

The star in question — named Trappist-1 after the Belgian telescope in Chile that made the discovery — is barely the size of Jupiter and located in the constellation Aquarius.

Other exoplanet searches have targeted bigger, brighter stars more like our sun, but the starlight in these cases can be so bright that it washes out the signatures of planets. By comparison, cool dwarf stars that emit infrared light, like Trappist-1, make it easier to spot potential worlds.

University of Liege astronomers in Belgium — lead study authors Michael Gillon and Emmanuel Jehin — built the Trappist telescope to observe 60 of the nearest ultra-cool dwarf stars. The risky effort paid off, de Wit noted in an email.

“Systems around these tiny stars are the only places where we can detect life on an Earth-sized exoplanet with our current technology,” Gillon said in a statement. “So if we want to find life elsewhere in the universe, this is where we should start to look.”

The two inner exoplanets take between 1.5 and 2.4 days to orbit the Trappist-1 star. The precise orbit time of the third planet is not known, but it falls somewhere between 4.5 days and 73 days. That puts the planets 20 times to 100 times closer to their star than Earth is to our sun, Gillon noted. The setup is more similar in scale to Jupiter’s moons than to our solar system, he added.

Although the two innermost planets are very close to the star, it showers them with only a few times the amount of energy that Earth receives from our own sun. The third exoplanet farther out may receive significantly less of such radiation than Earth does.

The astronomers speculate the two inner exoplanets may have pockets where life may exist, while the third exoplanet actually might fall within the habitable zone — real estate located at just the right distance from a star in order to harbor water and, possibly, life.

Spitzer and Hubble should answer whether the exoplanets have large and clear atmospheres, according to de Wit. They also might be able to detect water and methane, if molecules are present.

Future observatories, including NASA’s James Web Space Telescope set to launch in 2018, should unearth even more details.

Gillon and his colleagues identified the three exoplanets by observing regular dips in the infrared signals emanating from the Trappist-1 star, some 36 light-years away. A single light-year represents about 6 trillion miles.

The astronomers conducted the survey last year using the Transiting Planets and Planetesimals Small Telescope, or Trappist. It’s considered a prototype for a more expansive European project that will widen the search for potentially habitable worlds to 500 ultra-cool stars. This upcoming project is dubbed Speculoos — short for Search for Habitable Planets Eclipsing Ultra-Cool Stars.

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May 1, 2016

Newly Discovered Star Has an Almost Pure Oxygen Atmosphere

Filed under: Cool, Cosmology, Wierd — bferrari @ 5:25 pm
An artist's depiction of white dwarf stars Sirius A and B.

An artist’s depiction of white dwarf stars Sirius A and B.

A newly discovered star is unlike any ever found. With an outermost layer of 99.9 percent pure oxygen, its atmosphere is the most oxygen-rich in the known universe. Heck, it makes Earth’s meager 21 percent look downright suffocating.

The strange stellar oddity is a radically new type of white dwarf star, and was discovered by a team of Brazilian astronomers led by Kepler de Souza Oliveira at the Federal University of Rio Grande do Sul in Brazil. The star is unique in the known pool of 32,000 white dwarf stars, and is the only known star of any kind with an almost pure oxygen atmosphere. The new white dwarf has a mouthful of a name—SDSSJ124043.01+671034.68—but has been nicknamed ‘Dox’ (pronounced Dee-Awks) by Kepler’s team. The discovery was reported today in a paper in the journal Science.

THIS WHITE DWARF WAS INCREDIBLY UNEXPECTED.

“This white dwarf was incredibly unexpected,” says Kepler, “And because we had no idea anything like it could even exist, that made it all the more difficult to find.”

Missing Gas

Here’s a quick refresher: White dwarfs like Dox are the antiques of the cosmos. They’re the hyper-dense husks left over when stars largely sputter out of hydrogen and helium fuel. All but the largest 3 percent of stars end up as white dwarfs. Although Dox is only slightly bigger than our home planet, it’s 60 percent the mass of our sun.

Boris Gänsicke, an astronomer at the University of Warwick, in the UK, who was not involved in Dox’s discovery, confirms that the “exotic white dwarf… has an almost pure oxygen atmosphere, diluted only by traces of neon, magnesium, and silicon,” he writes in an essay accompanying the Science paper. “This chemical composition is unique among known [white dwarfs] and must arise from an extremely rare process.”

So, what makes Dox’s oxygen rich atmosphere so unexpected? Kepler explains that Dox presents more than a couple mysteries. For one, almost all other white dwarfs in the sky have an atmosphere thick with light elements like hydrogen and helium. These light elements are the final dregs of the star’s elemental fusion fuel that survived the star’s earlier life-cycle. Simply because of their weight, these light elements naturally float to the top of white dwarfs.

“What happened to all these light elements?” asks Kepler “How did they all get stripped away?”

Kepler also explains that although traces of heavier elements like carbon and oxygen can be detected in about one out of every five white dwarfs, it’s never quite like this. A white dwarf’s atmosphere is never purely one element, and is often diluted in a pool of lighter elements. Perhaps most perplexing, when oxygen atoms are found, they’re spied in far heavier white dwarfs. Smaller white dwarfs evolve from smaller stars, which don’t fuse together atoms into oxygen as they collapse. By all calculations, Dox would have had to be roughly double its weight to have even forged oxygen atoms in its earlier life. “You have to wonder where this oxygen even came from,” says Kepler.

In short, by simply being so weird, Dox completely defies our general, scientific understanding of how stars evolve and eventually form into white dwarfs. But Kepler suggests that maybe this shouldn’t be all that surprising. That’s because, he argues, scientists have often ignored the wacky results that can come about when stars grow and evolve while locked in a binary dance with other stars—rather than alone.

“I think the main problem is that we [astronomers] have dedicated the last 50 years to calculate the evolution of stars that are not interacting with each other, when at least 30 percent of stars interact with a binary companion,” he says.

Kepler believes Dox looks so strange because of an unlikely binary origin-story. His rough theory goes like this:

At some point Dox may have been a larger white dwarf, locked in a twirling ballet with another star much like our own Sun. These two stars were about the same distance apart as the Sun and Venus are. As Dox’s dance partner started to sputter out of Hydrogen fuel, it formed what’s called a red giant. It expanded rapidly—becoming so big that it actually engulfed the white dwarf in its outermost layer of gas. Kepler believes Dox would have started siphoning off the red giant’s gas onto itself. At some point during that siphoning process, “when it reached a few million degrees, it exploded. That explosion threw all types of matter out. That’s when [Dox] might have lost all its hydrogen and helium. This type of situation is known to have happened with other stars, although it’s never been seen to leave just oxygen,” he says.

The World’s Most Boring Job

Dox was discovered in a data mountain of 4.5 million individual star observations, collected over the last 15 years by a New Mexico observatory in a project called the Sloan Digital Sky Survey. It was found by way of a process so grueling that its initial discoverer—one of Kepler’s undergraduate students Gustavo Ourique—deserves a mention.

Ourique was looking for strange, new types of white dwarfs in a data pile of 300,000 possible observations. These observations are simple graphs about what colors of light came from each pinpoint source (called a spectral graph). Because a computer isn’t easily programmed with such a vague task as “find something weird and cool,” Ourique was challenged with the grunt-work task of physically looking at printed out pages of all 300,000 graphs.

“After a few months he could filter a one or two thousand each day, like reading a book” says Kepler. Yeah, but what a heartbreakingly boring book. That is, at least until it gets thrilling, because after half a year of scanning, and toward the end of the 300,000 graphs, Ourique came across Dox. Because of it’s oxygen atmosphere, Dox’s spectral graph looked truly unique, and he brought it to Kepler.

Ourique, man, you are a hero.

Source

April 25, 2016

Air Force maglev sled breaks record at 633 mph

Filed under: Cool, Government Policies, Military — bferrari @ 8:49 am

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In the New Mexico desert last month, a rocket-powered magnetically-levitated sled broke a world record after it blasted down a track at 633 miles per hour, faster than the cruising speed of a 747.

The test occurred at Holloman Air Force Base on a special 2100-foot track on March 4. Air Force video shows the one-ton vehicle rocketing down the track, a fiery, dusty plume behind it.

“We have a magnetically-levitated sled, where we use a very cold liquid helium to essentially levitate the sled via superconducting magnetics,” Lt. Col. Shawn Morgenstern, the commander of the 846th Test Squadron, said in the video.

“The test today was significantly faster than any test that we’ve previously done,” Morgenstern added.

The Air Force said that the sled accelerated at a rate of 928 feet per second. Before this test, the sled had reached 513 mph.

Magnetic levitation systems allow for vehicles to travel in a very low-friction environment, permitting incredibly fast speeds— last year, a Japanese maglev train traveled at 374 mph. And Elon Musk, the CEO of Tesla Motors and SpaceX, has proposed a system called the Hyperloop that would use a related technology to move people or cargo at breathtaking speeds.

Source

April 21, 2016

Why a Chip That’s Bad at Math Can Help Computers Tackle Harder Problems

Filed under: Cool, Gadgets — bferrari @ 1:54 pm

DARPA funded the development of a new computer chip that’s hardwired to make simple mistakes but can help computers understand the world.

Your math teacher lied to you. Sometimes getting your sums wrong is a good thing.

This chip can’t get its arithmetic right, but could make computers more efficient at tricky problems like analyzing images.

This chip can’t get its arithmetic right, but could make computers more efficient at tricky problems like analyzing images.

Why a Chip That’s Bad at Math Can Help Computers Tackle Harder Problems
DARPA funded the development of a new computer chip that’s hardwired to make simple mistakes but can help computers understand the world.
by Tom Simonite April 14, 2016
So says Joseph Bates, cofounder and CEO of Singular Computing, a company whose computer chips are hardwired to be incapable of performing mathematical calculations correctly. Ask it to add 1 and 1 and you will get answers like 2.01 or 1.98.

The Pentagon research agency DARPA funded the creation of Singular’s chip because that fuzziness can be an asset when it comes to some of the hardest problems for computers, such as making sense of video or other messy real-world data. “Just because the hardware is sucky doesn’t mean the software’s result has to be,” says Bates.

A chip that can’t guarantee that every calculation is perfect can still get good results on many problems but needs fewer circuits and burns less energy, he says.

Bates has worked with Sandia National Lab, Carnegie Mellon University, the Office of Naval Research, and MIT on tests that used simulations to show how the S1 chip’s inexact operations might make certain tricky computing tasks more efficient. Problems with data that comes with built-in noise from the real world, or where some approximation is needed, are the best fits. Bates reports promising results for applications such as high-resolution radar imaging, extracting 3-D information from stereo photos, and deep learning, a technique that has delivered a recent burst of progress in artificial intelligence.

In a simulated test using software that tracks objects such as cars in video, Singular’s approach was capable of processing frames almost 100 times faster than a conventional processor restricted to doing correct math—while using less than 2 percent as much power.

Bates is not the first to pursue the idea of using hand-wavy hardware to crunch data more efficiently, a notion known as approximate computing (see “10 Breakthrough Technologies 2008: Probabilistic Chips”). But DARPA’s investment in his chip could give the fuzzy math dream its biggest tryout yet.

Bates is building a batch of error-prone computers that each combine 16 of his chips with a single conventional processor. DARPA will get five such machines sometime this summer and plans to put them online for government and academic researchers to play with. The hope is that they can prove the technology’s potential and lure interest from the chip industry.

DARPA funded Singular’s chip as part of a program called Upside, which is aimed at inventing new, more efficient ways to process video footage. Military drones can collect vast quantities of video, but it can’t always be downloaded during flight, and the computer power needed to process it in the air would be too bulky.

It will take notable feats of software and even cultural engineering for imprecise hardware to take off. It’s not easy for programmers used to the idea that chips are always super-precise to adapt to ones that aren’t, says Christian Enz, a professor at the Swiss Federal Institute of Technology in Lausanne who has built his own approximate computing chips. New tools will be needed to help them do that, he says.

But Deb Roy, a professor at the MIT Media Lab and Twitter’s chief media scientist, says that recent trends in computing suggest approximate computing may find a readier audience than ever. “There’s a natural resonance if you are processing any kind of data that is noisy by nature,” he says. That’s become more and more common as programmers look to extract information from photos and video or have machines make sense of the world and human behavior, he adds.

 

The Curious Link Between the Fly-By Anomaly and the “Impossible” EmDrive Thruster

The same theory that explains the puzzling fly-by anomalies could also explain how the controversial EmDrive produces thrust.

About 10 years ago, a little-known aerospace engineer called Roger Shawyer made an extraordinary claim. Take a truncated cone, he said, bounce microwaves back and forth inside it and the result will be a thrust toward the narrow end of the cone. Voila … a revolutionary thruster capable of sending spacecraft to the planets and beyond. Shawyer called it the EmDrive.

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Shawyer’s announcement was hugely controversial. The system converts one type of energy into kinetic energy, and there are plenty of other systems that do something similar. In that respect it is unremarkable.

The conceptual problems arise with momentum. The system’s total momentum increases as it begins to move. But where does this momentum come from? Shawyer had no convincing explanation, and critics said this was an obvious violation of the law of conservation of momentum.

Shawyer countered with experimental results showing the device worked as he claimed. But his critics were unimpressed. The EmDrive, they said, was equivalent to generating a thrust by standing inside a box and pushing on the sides. In other words, it was snake oil.

Since then, something interesting has happened. Various teams around the world have begun to build their own versions of the EmDrive and put them through their paces. And to everyone’s surprise, they’ve begun to reproduce Shawyer’s results. The EmDrive, it seems, really does produce thrust.
In 2012, a Chinese team said it had measured a thrust produced by its own version of the EmDrive. In 2014, an American scientist built an EmDrive and persuaded NASA to test it with positive results.

And last year, NASA conducted its own tests in a vacuum to rule out movement of air as the origin of the force. NASA, too, confirmed that the EmDrive produces a thrust. In total, six independent experiments have backed Shawyer’s original claims.

That leaves an important puzzle—how to explain the seeming violation of conservation of momentum.

Today we get an answer of sorts thanks to the work of Mike McCulloch at Plymouth University in the U.K. McCulloch’s explanation is based on a new theory of inertia that makes startling predictions about the way objects move under very small accelerations.

First some background. Inertia is the resistance of all massive objects to changes in motion or accelerations. In modern physics, inertia is treated as a fundamental property of massive objects subjected to an acceleration. Indeed, mass can be thought of as a measure of inertia. But why inertia exists at all has puzzled scientists for centuries.

McCulloch’s idea is that inertia arises from an effect predicted by general relativity called Unruh radiation. This is the notion that an accelerating object experiences black body radiation. In other words, the universe warms up when you accelerate.

According to McCulloch, inertia is simply the pressure the Unruh radiation exerts on an accelerating body.

That’s hard to test at the accelerations we normally observe on Earth. But things get interesting when the accelerations involved are smaller and the wavelength of Unruh radiation gets larger.

At very small accelerations, the wavelengths become so large they can no longer fit in the observable universe. When this happens, inertia can take only certain whole-wavelength values and so jumps from one value to the next. In other words, inertia must quantized at small accelerations.

McCulloch says there is observational evidence for this in the form of the famous fly by anomalies. These are the strange jumps in momentum observed in some spacecraft as they fly past Earth toward other planets. That’s exactly what his theory predicts.

Testing this effect more carefully on Earth is hard because the accelerations involved are so small. But one way to make it easier would be to reduce the size of allowed wavelengths of Unruh radiation. “This is what the EmDrive may be doing,” says McCulloch.

The idea is that if photons have an inertial mass, they must experience inertia when they reflect. But the Unruh radiation in this case is tiny. So small in fact that it can interact with its immediate environment. In the case of the EmDrive, this is the truncated cone.

The cone allows Unruh radiation of a certain size at the large end but only a smaller wavelength at the other end. So the inertia of photons inside the cavity must change as they bounce back and forth. And to conserve momentum, this must generate a thrust.

McCulloch puts this theory to the test by using it to predict the forces it must generate. The precise calculations are complex because of the three-dimensional nature of the problem, but his approximate results match the order of magnitude of thrust in all the experiments done so far.

Crucially, McCulloch’s theory makes two testable predictions. The first is that placing a dielectric inside the cavity should enhance the effectiveness of the thruster.

The second is that changing the dimensions of the cavity can reverse the direction of the thrust. That would happen when the Unruh radiation better matches the size of the narrow end than the large end. Changing the frequency of the photons inside the cavity could achieve a similar effect.

McCulloch says there is some evidence that exactly this happens. “This thrust reversal may have been seen in recent NASA experiments,” he says.

That’s an interesting idea. Shawyer’s EmDrive has the potential to revolutionize spaceflight because it requires no propellant, the biggest limiting factor in today’s propulsion systems. But in the absence of any convincing explanation for how it works, scientists and engineers are understandably wary.

McCulloch’s theory could help to change that, although it is hardly a mainstream idea. It makes two challenging assumptions. The first is that photons have inertial mass. The second is that the speed of light must change within the cavity. That won’t be easy for many theorists to stomach.

But as more experimental confirmations of Shawyer’s EmDrive emerge, theorists are being forced into a difficult position. If not McCulloch’s explanation, then what?

Ref: arxiv.org/abs/1604.03449 : Testing Quantized Inertia on the EmDrive

April 19, 2016

Large Hadron Collider results may hint at a new era of physics

Filed under: Big Bang, Black Holes, Cool, Wierd — bferrari @ 2:00 pm
The LHC (Large Hadron Collider) tunnel. (REUTERS/Denis Balibouse)

The LHC (Large Hadron Collider) tunnel. (REUTERS/Denis Balibouse)

Are we about to enter a new era of physics?  Data collected by the Large Hadron Collider in Switzerland may have identified particle activity that doesn’t fit the standard laws of physics.

The analysis by scientists including physicists at the Institute of Nuclear Physics at the Polish Academy of Sciences (IFJ PAN) could have huge scientific implications.

“There are some indications that physicists working at the LHC accelerator at the European Organization for Nuclear Research (CERN) near Geneva may see the first traces of physics beyond the current theory which describes the structure of matter,” said the IFJ PAN, in a recent press release.

The structure of matter is described by a theoretical framework called The Standard Model, which identifies the roles played by different particles. Boson particles, for example, are carriers of forces, whereas photons are related to electromagnetic interactions. Matter is formed by particles called fermions.

However, scientists, analyzing data collected by the LHCb experiment in 2011 and 2012, noticed an anomaly in the decay of a particle called a B Meson. According to the research, the traditional method for determining the particle’s decay may lead to false results.

Related: Science breakthrough? Physicists may have discovered Higgs boson relative

Could the anomaly hint at a new understanding of the Universe? Scientists are certainly intrigued by the anomaly. To put it in terms of the cinema, where we once only had a few leaked scenes from an much-anticipated blockbuster, the LHC has finally treated fans to the first real trailer,” said Professor Mariusz Witek of IFJ PAN, in the release.

Witek notes that the framework used to describe the structure of matter poses plenty of questions for scientists. “The Standard Model cannot explain all the features of the Universe,” he said. “It doesn’t predict the masses of particles or tell us why fermions are organized in three families. How did the dominance of matter over antimatter in the universe come about? What is dark matter? Those questions remain unanswered.”

To further illustrate his point, the Professor notes that gravity isn’t even included in the Standard Model.

However, scientists caution that more research is needed on the B Meson anomaly. “We can’t call it a discovery. Not yet,” said the IFJ PAN.

CERN spokesman Arnaud Marsollier told FoxNews.com that the B Meson data, which first emerged last year, are not conclusive. “More data are needed before we can tell anything significant on this, so we will have to wait for the LHC to restart (soon),” he explained via email, noting the importance of patience when recording and analyzing data. “Science needs time!” he added.

Related: Revamped Large Hadron Collider set to restart

CERN is currently starting powering tests on the huge particle accelerator. “Beams should be back by the end of the month or early April, and collisions sometimes next month if everything goes as planned,” said Marsollier.

Oxford University Physics Professor Guy Wilkinson, who serves as the spokesman for the LHCb experiment, told FoxNews.com that CERN’s B Meson data is “extremely interesting,” but noted that it could be a couple of years before scientists perform a full analysis. “When we analyse this new sample in a year or two we will be able to make a fresh and, I hope, more categorical statement on this topic,” he explained, via email.

The 17-mile LHC was built between 1998 and 2008 to help scientists test some theories of particle and high-energy physics and advance understanding of physical laws.

In 2012 the Collider won global acclaim with the discovery of the long-sought Higgs boson  particle, which explains the behavior of other particles. Physicists Peter Higgs and Francois Englert were subsequently awarded the 2013 Nobel Prize in Physics.

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