NASA engineer's 'helical engine' violate the law of physics

 Rocket engines that don’t need propellant have been proposed before: this is an illustration of the EM-driveIllustration by luismmolina/iStock / Getty Images Plus


For every action, there is a reaction: that is the principle on which  all space rockets operate, blasting propellant in one direction to  travel in the other. But one NASA engineer believes he could take us to  the stars without any propellant at all.

Designed by David Burns at NASA’s Marshall Space Flight Center in  Alabama, the “helical engine” exploits mass-altering effects known to  occur at near-light speed. Burns has posted a paper describing the concept to NASA’s technical reports server.

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It has been met with scepticism from some quarters, but Burns  believes his concept is worth pursuing. “I’m comfortable with throwing  it out there,” he says. “If someone says it doesn’t work, I’ll be the  first to say, it was worth a shot.”                     

To get to grips with the principle of Burns’s engine, picture a box  on a frictionless surface. Inside that box is a rod, along which a ring  can slide. If a spring inside the box gives the ring a push, the ring  will slide along the rod one way while the box will recoil in the other.  When the ring reaches the end of the box, it will bounce backwards, and  the box’s recoil direction will switch too. This is action-reaction –  also known as Newton’s third law of motion – and in normal  circumstances, it restricts the box to wiggling back and forth

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But, Burns asks, what if the ring’s mass is much greater when it slides  in one direction than the other? Then it would give the box a greater  kick at one end than the other. Action would exceed reaction and the box  would accelerate forwards

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This mass changing isn’t prohibited by physics. Einstein’s theory of  special relativity says that objects gain mass as they are driven  towards the speed of light, an effect that must be accounted for in  particle accelerators. In fact, a simplistic implementation of Burns’s  concept would be to replace the ring with a circular particle  accelerator, in which ions are swiftly accelerated to relativistic speed  during one stroke, and decelerated during the other.

But Burns thinks it would make more sense to ditch the box and rod  and employ the particle accelerator for the lateral as well as the  circular movement – in which case, the accelerator would need to be  shaped like a helix.

Frictionless space

It would also need to be big – some 200 metres long and 12 metres in  diameter – and powerful, requiring 165 megawatts of power to generate  just 1 newton of thrust, which is about the same force you use to type  on a keyboard. For that reason, the engine would only be able to reach  meaningful speeds in the frictionless environment of space. “The engine  itself would be able to get to 99 per cent the speed of light if you had  enough time and power,” says Burns.

Propellant-less proposals aren’t new. In the late 1970s, Robert Cook,  a US inventor, patented an engine that supposedly converted centrifugal  force into linear motion. Then, in the early 2000s, British inventor  Roger Shawyer proposed the EM drive, which he claimed could convert  trapped microwaves into thrust. Neither concept has been successfully  demonstrated and both are widely assumed to be impossible, due to  violation of the conservation of momentum, a core physical law.

Martin Tajmar at the Dresden University of Technology in Germany, who has performed tests on the EM Drive,  believes the helical engine will probably suffer the same problem. “All  inertial propulsion systems – to my knowledge – never worked in a  friction-free environment,” he says. This machine makes use of special  relativity, unlike the others, which complicates the picture, he says,  but “unfortunately there is always action-reaction”.


Burns has worked on his design in private, without any sponsorship  from NASA, and he admits his concept is massively inefficient. However,  he says there is potential to harvest much of the energy that the  accelerator loses in heat and radiation. He also suggests ways that  momentum could be conserved, such as in the spin of the accelerated  ions.

“I know that it risks being right up there with the EM drive and cold  fusion,” he says. “But you have to be prepared to be embarrassed. It is  very difficult to invent something that is new under the sun and  actually works.”

Read more: https://www.newscientist.com/article/2218685-nasa-engineers-helical-engine-may-violate-the-laws-of-physics/#ixzz629oXKwUz


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Are Black Holes Actually Dark Energy Stars?

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 George Chapline believes that the Event Horizon Telescope will offer evidence that black holes are really dark energy stars. Photo by NASA.

What  does the supermassive black hole at the center of the Milky Way look  like? We might find out. The Event Horizon Telescope—really a virtual  telescope with an effective diameter of the Earth—has been pointing at  Sagittarius A* for the last several years. Most researchers in the  astrophysics community expect that its images, taken from telescopes all  over the Earth, will show the telltale signs of a black hole: a bright  swirl of light, produced by a disc of gases trapped in the black hole’s  orbit, surrounding a black shadow at the center—the event horizon. This  encloses the region of space where the black-hole singularity’s  gravitational pull is too strong for light to escape.              

                    But George Chapline, a physicist at the Lawrence  Livermore National Laboratory, doesn’t expect to see a black hole. He  doesn’t believe they’re real. In 2005, he told Nature that “it’s a  near certainty that black holes don’t exist” and—building on previous  work he’d done with physics Nobel laureate Robert Laughlin—introduced an  alternative model that he dubbed “dark energy stars.” Dark energy is a  term physicists use to describe a peculiar kind of energy that appears  to permeate the entire universe. It expands the fabric of spacetime  itself, even as gravity attempts to bring objects closer together.  Chapline believes that the immense energies in a collapsing star cause  its protons and neutrons to decay into a gas of photons and other  elementary particles, along with what he refers to as “droplets of  vacuum energy.” These form a “condensed” phase of spacetime—much like a  gas under enough pressure transitions to liquid—that has a much higher  density of dark energy than the spacetime surrounding the star. This  provides the pressure necessary to hold gravity at bay and prevent a  singularity from forming. Without a singularity in spacetime, there is  no black hole.              

                    The idea has found no support in the astrophysical  community—over the last decade, Chapline’s papers on this topic have  garnered only single-digit citations. His most popular paper in particle  physics, by contrast, has been cited over 600 times. But Chapline  suspects his days of wandering in the scientific wilderness may soon be  over. He believes that the Event Horizon Telescope will offer evidence  that dark energy stars are real.              

                            This strange toroidal geometry isn’t a bug of dark energy stars, but a feature.                      

                    The idea goes back to a 2000 paper,  with Evan Hohlfeld and David Santiago, in which Chapline and Laughlin  modeled spacetime as a Bose-Einstein condensate—a state of matter that  arises when taking an extremely low-density gas to extremely low  temperatures, near absolute zero. Chapline and Laughlin’s model is  quantum mechanical in nature: General relativity emerges as a  consequence of the way that the spacetime condensate behaves on large  scales. Spacetime in this model also undergoes phase transformations  when it gains or loses energy. Other scientists find this to be a  promising path, too. A 2009 paper by a group of Japanese physicists stated that “[Bose-Einstein  Condensates] are one of the most promising quantum fluids for”  analogizing curved spacetime.        

                    Chapline and Laughlin argue that they can describe the  collapsed stars that most scientists take to be black holes as regions  where spacetime has undergone a phase transition. They find that the  laws of general relativity are valid everywhere in the vicinity of the  collapsed star, except at the event horizon, which marks the boundary  between two different phases of spacetime.              

                    In the condensate model the event horizon surrounding a  collapsed star is no longer a point of no return but instead a  traversable, physical surface. This feature, along with the lack of a  singularity that is the signature feature of black holes, means that  paradoxes associated with black holes, like the destruction of information,  don’t arise. Laughlin has been reticent to conjecture too far beyond  his and Chapline’s initial ideas. He believes Chapline is onto something  with dark energy stars, “but where we part company is in the amount of  speculating we are willing to do about what ‘phase’ of the vacuum might  be inside” what most scientists call black holes, Laughlin said. He’s  holding off until experimental data reveals more about the interior  phase. “I will then write my second paper on the subject,” he said.              

                    In recent years Chapline has continued to refine his  dark energy star model in collaboration with several other authors,  including Pawel Mazur of the University of South Carolina and Piotr  Marecki of Leipzig University. He’s concluded that dark energy stars  aren’t spherical or oblate, like black holes. Instead, they have the  shape of a torus, or donut. In a rotating compact object, like a dark  energy star, Chapline believes quantum effects in the spacetime  condensate generate a large vortex along the object’s axis of rotation.  Because the region inside the vortex is empty—think of the depression  that forms at the center of whirlpool—the center of the dark energy star  is hollow, like an apple without its core. A similar effect is observed  when quantum mechanics is used to model rotating drops of superfluid.  There too, a central vortex can form at the center of a rotating drop  and, surprisingly, change its shape from a sphere to a torus.                

                            In the condensate model the event horizon  surrounding a collapsed star is no longer a point of no return but  instead a traversable, physical surface.                      

                    For Chapline, this strange toroidal geometry isn’t a bug  of dark energy stars, but a feature, as it helps explain the origin and  shape of astrophysical jets—the highly energetic beams of ionized  matter that are generated along the axis of rotation of a compact object  like a black hole. Chapline believes he’s identified a mechanism in  dark energy stars that explains observations of astrophysical jets  better than mainstream ones, which posit that energy is extracted from  the accretion disk outside of a black hole and focused into a narrow  beam along the black hole’s axis of rotation. To Chapline, matter and  energy falling toward a dark energy star would make its way to the inner  throat (the “donut hole”), where electrons orbiting the throat would,  as in a Biermann Battery, generate magnetic fields powerful enough to drive the jets.        

                    Chapline points to experimental work where  scientists, at the OMEGA Laser Facility at the University of Rochester,  created magnetized jets using lasers to form a ring-like excitation on a  flat surface. Though the experiments were not conducted with dark  energy stars in mind, Chapline believes it provides support for his  theory since the ring-like excitation—Chapline calls it a “ring of  fire”—is exactly what he would expect to happen along the throat of a  dark energy star. He believes the ring could be the key to supporting  the existence of dark energy stars. “This ought to eventually show up  clearly” in the Event Horizon Telescope images, Chapline said, referring  to the ring.         

Black Hole vs. Dark Energy Star: When  viewed from the top down, a dark energy star has a central opening, the  donut hole. Chapline believes that matter and energy rotating around the  central opening (forming the “ring of fire”) is the source of the  astrophysical jets observed by astronomers in the vicinity of what most  believe to be black holes.

                    Chapline also points out that dark energy stars will not  be completely opaque to light, as matter and light can pass into, but  also out of, a dark energy star. A dark energy star won’t have a  completely black interior—instead it will show a distorted image of any  stars behind it. Other physicists, though, are skeptical that these  kinds of deviations from conventional black hole models would show up in  the Event Horizon Telescope data. Raul Carballo-Rubio, a physicist at  the International School for Advanced Studies, in Trieste, Italy, has  developed his own alternative model to black holes known as  semi-classical relativistic stars. Speaking more generally about  alternative black hole models Caraballo-Rubio said, “The differences  [with black holes] that would arise in these models are too minute to be  detected” by the Event Horizon Telescope.        

                    Chapline plans to discuss his dark energy star  predictions in December 2018, at the Kavli Institute for Theoretical  Physics in Santa Barbara. But even if his predictions are confirmed, he  said he doesn’t expect the scientific community to become convinced  overnight. “I expect that for the next few years the [Event Horizon  Telescope] people will be confused by what they see.”              

                    Jesse Stone is a freelance writer based in Iowa City, Iowa. Reach him at jessebstone@gmail.com.              

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mars rover pics and info

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 .It has now been just more than 2,000 days since NASA’s Curiosity rover landed on the surface of Mars. In the days (or “sols,” as they are called on Mars) since its complex sky-crane touchdown, Curiosity has made countless discoveries with multiple instruments, including drills, lasers, and an array of imaging instruments that so far have sent 468,926 images back to Earth. Gathered here are a few images of Mars from Curiosity over the past few years.

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  • A selfie on Mars, taken by NASA's Mars rover, Curiosity, on January 23, 2018, or Sol 1943, using its Mars Hand Lens Imager. Image stitched together from a series of panoramic images; sky artificially extended. #
    NASA / JPL-Caltech / MSSS

  • Two sizes of wind-sculpted ripples are evident in this view of the top surface of a Martian sand dune. Sand dunes and the smaller type of ripples also exist on Earth. The larger ripples—roughly 10 feet (three meters) apart—are a type not seen on Earth nor previously recognized as a distinct type on Mars. The mast camera (mastcam) on NASA's Curiosity rover took the multiple component images of this scene on December 13, 2015, during the 1,192nd Martian day of the rover's work on Mars.The location is part of Namib Dune in the Bagnold Dune Field, which forms a dark band along the northwestern flank of Mount Sharp. #
    JPL-Caltech / MSSS / NASA

  • This image was taken by Curiosity's mastcam on Sol 1648, or March 26, 2017. #
    JPL-Caltech / MSSS / NASA

  • Curiosity pauses at the site from which it reached down to drill into a rock target called "Buckskin" on lower Mount Sharp in this low-angle self-portrait taken August 5, 2015, and released August 19, 2015. The selfie combines several component images taken by Curiosity's Mars Hand Lens Imager (MAHLI) during the 1,065th Martian day of the rover's work on Mars. #
    NASA / Reuters

  • Curiosity recorded this view of the sun setting at the close of the mission's 956th Martian day, on April 15, 2015, from the rover's location in Gale Crater, Mars. #
    JPL-Caltech / MSSS / Texas A&M Univ via Getty / NASA / Getty

  • On September 9, 2012, when it was just starting out, a close view of two of the left wheels of Curiosity. In the distance is the lower slope of Mount Sharp. #
    JPL-Caltech / Malin Space Science Systems / NASA / Reuters

  • Years later, on April 18, 2016, NASA used the MAHLI camera to check the condition of the wheels once again. This image of Curiosity's left-middle and left-rear wheels is part of an inspection set taken during Sol 1,315. Holes and tears in the wheels worsened significantly during 2013 as Curiosity was crossing terrain studded with sharp rocks on its route near its 2012 landing site to the base of Mount Sharp. Team members are keeping a close eye for when any of the zig-zag-shaped treads, call grousers, begin to break. Longevity testing with identical wheels on Earth indicates that when three grousers on a given wheel have broken, that wheel has reached about 60 percent of its useful mileage. Curiosity's six aluminum wheels are about 20 inches (50 centimeters) in diameter and 16 inches (40 centimeters) wide. Each of the six wheels has its own drive motor, and the four corner wheels also have steering motors. #
    JPL-Caltech / MSSS / NASA

  • NASA's Curiosity Mars rover used the navcam on its mast for this look back after finishing a drive of 328 feet (100 meters) on Sol 548 (February 19, 2014). The rows of rocks just to the right of the fresh wheel tracks in this view are an outcrop called "Junda." The rows form striations on the ground, a characteristic seen in some images of this area taken from orbit. For scale, the distance between Curiosity's parallel wheel tracks is about 9 feet (2.7 meters). #
    JPL-Caltech / NASA

  • This view from NASA's Curiosity Mars Rover shows the downwind side of Namib Dune, which stands about 13 feet (4 meters) high. The site is part of Bagnold Dunes, a band of dark sand dunes along the northwestern flank of Mars's Mount Sharp. The component images stitched together into this scene were taken with Curiosity's navcam on December 17, 2015, during Sol 1196. #
    JPL-Caltech / NASA

  • The dark, smooth-surfaced object at the center of this October 30, 2016, image from the mastcam on Curiosity was examined with laser pulses and confirmed to be an iron-nickel meteorite. The grid of shiny points visible on the object resulted from that laser zapping by Curiosity's Chemistry and Camera (ChemCam) instrument. The meteorite is about the size of a golf ball. It is informally named "Egg Rock," after a site in Maine. Locations around Bar Harbor, Maine, are the naming theme for an area on Mars' Mount Sharp that Curiosity reached in October. Iron-nickel meteorites are a common class of space rocks found on Earth, and previous examples have been found on Mars, but Egg Rock is the first on Mars to be examined with a laser-firing spectrometer. The scene is presented with a color adjustment that approximates white balancing, to resemble how the rocks and sand would appear under daytime lighting conditions on Earth. Figure one includes a scale bar of five centimeters (about two inches). #
    JPL-Caltech / MSSS / NASA

  • This view from the Mastcam shows a hillside outcrop with layered rocks within the Murray Buttes region on lower Mount Sharp. The buttes and mesas rising above the surface in this area are eroded remnants of ancient sandstone that originated when winds deposited sand after lower Mount Sharp had formed. Curiosity closely examined that layer—called the "Stimson formation"—during the first half of 2016, while crossing a feature called "Naukluft Plateau" between two exposures of the Murray formation. The layering within the sandstone is called "cross-bedding," and indicates that the sandstone was deposited by wind as migrating sand dunes. The image was taken on September 8, 2016, during Sol 1454. #
    JPL-Caltech / MSSS / NASA

  • A view of the two moons of Mars comes from a set of images taken by Curiosity as the larger moon, Phobos, passed in front of the smaller one, Deimos, from Curiosity's perspective, on August 1, 2013. Curiosity used the telephoto-lens camera of its two-camera mastcam instrument to catch a series of images of the moons before, during, and after the occultation of Deimos by Phobos. This processed image stacks information from several images of each moon to enhance the visibility of smaller features. The two moons's positions relative to each other are taken from one of the frames from just before the occultation. On Phobos, Stickney Crater is visible on the top. It is on the leading hemisphere of Phobos. Hall Crater, in the south, is the prominent feature on the left hand side. #
    JPL-Caltech / Malin Space Science Systems / Texas A&M University / NASA

  • A view from above. This image from NASA's Mars Reconnaissance Orbiter on April 8, 2015, catches sight of NASA's Curiosity Mars rover passing through a valley called Artist's Drive on the lower slope of Mount Sharp. The image is from the orbiter's High Resolution Imaging Science Experiment (HiRISE) camera. It shows the rover's position after a drive of about 75 feet (23 meters) during Sol 949. North is toward the top, and the rover's shadow extends toward the right. #
    JPL-Caltech / Univ. of Arizona / NASA

  • This dark mound, called "Ireson Hill," rises about 16 feet (5 meters) above redder layered outcrop material of the Murray formation on lower Mount Sharp, Mars, near a location where NASA's Curiosity rover examined a linear sand dune in February 2017. Researchers used the rover's mastcam on February 2, 2017, during Sol 1598 to take the multiple images combined into this scene. The faint horizon in the distance beyond Ireson Hill is part of the rim of Gale Crater. #
    JPL-Caltech / MSSS / NASA

  • Two views of a century-old penny on mars. This penny is part of a camera calibration target attached to Curiosity. The MAHLI camera on the rover took this image during Sol 34 (September 9, 2012). "When a geologist takes pictures of rock outcrops she is studying, she wants an object of known scale in the photographs," said MAHLI Principal Investigator Ken Edgett, of Malin Space Science Systems, San Diego. "If it is a whole cliff face, she'll ask a person to stand in the shot. If it is a view from a meter or so away, she might use a rock hammer. If it is a close-up, as the MAHLI can take, she might pull something small out of her pocket. Like a penny." Edgett bought the special penny that's aboard Curiosity with funds from his own pocket. It is a 1909 "VDB" cent from the first year Lincoln pennies were minted, the centennial of Abraham Lincoln's birth, with the VDB initials of the coin's designer—Victor David Brenner—on the reverse. The penny is on the MAHLI calibration target as a tip of the hat to geologists's informal practice of placing a coin or other object of known scale in their photographs. "Everyone in the United States can recognize the penny and immediately know how big it is, and can compare that with the rover hardware and Mars materials in the same image," Edgett said. "The public can watch for changes in the penny over the long term on Mars. Will it change color? Will it corrode? Will it get pitted by windblown sand?" At right, the same penny, re-photographed on December 2, 2017, or Sol 1892, showing almost no visible wear, with only a small coating of dust. #
    JPL / NASA

  • This image from Curiosity shows wheel tracks printed by the rover as it drove on the sandy floor of a lowland called "Hidden Valley" on the route toward Mount Sharp. The image was taken during the 709th Martian day of the rover's work on Mars (August 4, 2014). #
    JPL-Caltech / NASA

  • A vantage point on Vera Rubin Ridge provided Curiosity this detailed look back over the area where it began its mission inside Gale Crater, plus more-distant features of the crater. This view toward the north-northeast combines eight images taken by the right-eye telephoto-lens camera of Curiosity's mastcam. The component images were taken on October 25, 2017, during Sol 1856. At that point, Curiosity had gained 1,073 feet (327 meters) in elevation and driven 10.95 miles (17.63 kilometers) from its landing site. #
    JPL-Caltech / MSSS / NASA

  • This self-portrait of NASA's Curiosity Mars rover shows the vehicle at Namib Dune, where the rover's activities included scuffing into the dune with a wheel and scooping samples of sand for laboratory analysis. The scene was taken on January 19, 2016, during Sol 1228. #
    JPL-Caltech / MSSS / NASA

  • Beyond a dark sand dune closer to the rover, a Martian dust devil passes in front of the horizon in this sequence of images from Curiosity. The rover's navigation camera made this series of observations on February 4, 2017, in the summertime afternoon of Sol 1599. Set within a broader view centered at south-southwest, the rectangular area outlined in black was imaged multiple times over a span of several minutes to check for dust devils. Images from the period with most activity are shown in the inset area. Contrast has been modified to make frame-to-frame changes easier to see. The images are in pairs that were taken about 12 seconds apart, with an interval of about 90 seconds between pairs. Timing is accelerated and not fully proportional in this animation. On Mars as on Earth, dust devils are whirlwinds that result from sunshine warming the ground, prompting convective rising of air that has gained heat from the ground. Observations of Martian dust devils provide information about wind directions and interaction between the surface and the atmosphere. #
    NASA / JPL-Caltech / TAMU

  • The Mars Hand Lens Imager camera on the robotic arm of Curiosity used electric lights at night to illuminate this view of Martian sand grains dumped on the ground after sorting with a sieve. The view covers an area roughly 1.1 inches by 0.8 inch (2.8 centimeters by 2.1 centimeters). The grains seen here were too large to pass through a sieve with 150-micron (0.006 inch) pores. They were part of the sand in the first scoop collected by Curiosity at Namib Dune. A different portion of that scoop—consisting of grains small enough to pass through the 150-micron sieve—was delivered to the rover's on-board laboratory instruments for analysis. The images combined into this focus-merged view were taken on January 22, 2016, after dark on Sol 1230. #
    JPL-Caltech / MSSS / NASA

  • This composite image looking toward the higher regions of Mount Sharp was taken on September 9, 2015, by NASA's Curiosity rover. In the foreground, about two miles (three kilometers) from the rover, is a long ridge teeming with hematite, an iron oxide. Just beyond is an undulating plane rich in clay minerals. And just beyond that are a multitude of rounded buttes, all high in sulfate minerals. The changing mineralogy in these layers of Mount Sharp suggests a changing environment in early Mars, though all involve exposure to water billions of years ago. Further back in the image are striking, light-toned cliffs in rock that may have formed in drier times and now are heavily eroded by winds. The colors are adjusted so that rocks look approximately as they would if they were on Earth, to help geologists interpret the rocks. This "white balancing" to adjust for the lighting on Mars overly compensates for the absence of blue on Mars, making the sky appear light blue and sometimes giving dark, black rocks a blue cast. #
    JPL-Caltech / MSSS / NASA

  • This look back at a dune that NASA's Curiosity Mars rover drove across was taken by the rover's mastcam during Sol 538, or February 9, 2014. The rover had driven over the dune three days earlier. The dune is about three feet (one meter) tall in the middle of its span across an opening called Dingo Gap. #
    JPL-Caltech / MSSS / NASA

  • Curiosity drilled this hole to collect sample material from a rock target called Buckskin on July 30, 2015, during Sol 1060. The diameter is slightly smaller than a dime. Rock powder from the collected sample was subsequently delivered to a laboratory inside the rover for analysis. The rover's drill did not experience any sign during this sample collection of an intermittent short-circuiting issue that was detected earlier in 2015. The Buckskin target is in an area near Marias Pass on lower Mount Sharp where Curiosity had detected unusually high levels of silica and hydrogen. #
    JPL-Caltech / MSSS / NASA

  • A panorama of the Martin landscape made from a mosaic of images taken by Curiosity on Sol 1276, or March 9, 2016. #
    JPL-Caltech / MSSS / NASA


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