# Lately in Science, not Fiction. Part 3
1. Universe is Not Expanding After All, Controversial Study Suggests
"According to a team of astrophysicists led by Eric Lerner from
Lawrenceville Plasma Physics, the Universe is not expanding at all.
In their study, the scientists tested one of the striking predictions of the Big Bang Theory – that ordinary geometry does not work at great distances.
In the space around us, on Earth, in the Solar System and our Milky Way Galaxy, as similar objects get farther away, they look fainter and smaller. Their surface brightness, that is the brightness per unit area, remains constant.
In contrast, the Big Bang theory tells us that in an expanding Universe objects actually should appear fainter but bigger. Thus in this theory, the surface brightness decreases with the distance. In addition, the light is stretched as the Universe expanded, further dimming the light.
So in an expanding Universe the most distant galaxies should have hundreds of times dimmer surface brightness than similar nearby galaxies, making them actually undetectable with present-day telescopes.
But that is not what observations show, as demonstrated by this new study published in the International Journal of Modern Physics D.
The scientists carefully compared the size and brightness of about a thousand nearby and extremely distant galaxies. They chose the most luminous spiral galaxies for comparisons, matching the average luminosity of the near and far samples.
Contrary to the prediction of the Big Bang theory, they found that the surface brightnesses of the near and far galaxies are identical.
These results are consistent with what would be expected from ordinary geometry if the Universe was not expanding, and are in contradiction with the drastic dimming of surface brightness predicted by the expanding Universe hypothesis.
In their study, the scientists tested one of the striking predictions of the Big Bang Theory – that ordinary geometry does not work at great distances.
In the space around us, on Earth, in the Solar System and our Milky Way Galaxy, as similar objects get farther away, they look fainter and smaller. Their surface brightness, that is the brightness per unit area, remains constant.
In contrast, the Big Bang theory tells us that in an expanding Universe objects actually should appear fainter but bigger. Thus in this theory, the surface brightness decreases with the distance. In addition, the light is stretched as the Universe expanded, further dimming the light.
So in an expanding Universe the most distant galaxies should have hundreds of times dimmer surface brightness than similar nearby galaxies, making them actually undetectable with present-day telescopes.
But that is not what observations show, as demonstrated by this new study published in the International Journal of Modern Physics D.
The scientists carefully compared the size and brightness of about a thousand nearby and extremely distant galaxies. They chose the most luminous spiral galaxies for comparisons, matching the average luminosity of the near and far samples.
Contrary to the prediction of the Big Bang theory, they found that the surface brightnesses of the near and far galaxies are identical.
These results are consistent with what would be expected from ordinary geometry if the Universe was not expanding, and are in contradiction with the drastic dimming of surface brightness predicted by the expanding Universe hypothesis.
“Of course, you can hypothesize that galaxies were much smaller, and thus had hundreds of times greater intrinsic surface brightness in the past, and that, just by coincidence, the Big Bang dimming exactly cancels that greater brightness at all distances to produce the illusion of a constant brightness, but that would be a very big coincidence,” Mr Lerner said.
That was not the only startling result of their research. In order to apply the surface brightness test, first proposed in 1930 by physicist Richard C. Tolman, the team had to determine the actual luminosity of the galaxies, so as to match near and far galaxies.
To do that, the astrophysicists had to link the distance to the galaxies with their redshift. They hypothesized that the distance is proportional to the redshift at all distances, as is well verified to be the case in the nearby Universe.
They checked this relation between redshift and distance with the data on supernova brightness that has been used to measure the hypothesized accelerated expansion of the Universe.
“It is amazing that the predictions of this simple formula are as good as the predictions of the expanding Universe theory, which include complex corrections for hypothetical dark matter and dark energy,” said study co-author Dr Renato Falomo of the Osservatorio Astronomico di Padova, Italy.
Dr Riccardo Scarpa from the Instituto de Astrofısica de Canarias, Spain, who is a co-author of the study, added: “again you could take this to be merely coincidental, but it would be a second big coincidence.”
Therefore if the Universe is not expanding, the redshift of light with increasing distance must be caused by some other phenomena – something that happens to the light itself as it travels through space.
“We are not speculating now as to what could cause the redshift of light,” Mr Lerner said. ”However, such a redshift, which is not associated with expansion, could be observed with suitable spacecraft within our own Solar System in the future.”
More about (whole text) here: LINK*
2. Scientists discovered exoplanet in the ecosphere around the star - Proxima Centauri, the nearest to our solar system.
"Just over four light-years from the solar system is a red dwarf called Proxima Centauri. This cool star in the Centaurus Constellation is too weak to see it with the naked eye and is close to a much brighter pair of stars known as Alpha Centauri AB. On Proxima b are the conditions for the occurrence of liquid water, she circles its host star every 11 days. This rocky world is slightly more massive than Earth and is the closest exoplanet for us - it can also be the next hotbed of life outside the solar system."
More info here: LINK*
3. Hubble found most distant galaxy, it existed only 400 million years after the Big Bang
Scientists from NASA and the ESA
have pushed the Hubble Space Telescope to a new distance record. The
record comes as the team of researchers has broken the cosmic distance
record by measuring the distance to the most distant galaxy ever seen in
the Universe. According to scientists, the galaxy they measured existed
only 400 million years after the Big Bang.
This feat marks the first item that the distance of an object so far away has been measured from its spectrum making the distance measurement extremely accurate. The newly measured galaxy is called GN-z11 and while the distant galaxy is very faint, the scientists say that it is unusually bright considering how far it is from Earth. With the discovery of a galaxy this bright, yet so distant from Earth the scientists believe there is evidence of other brighter than expected galaxies in other Hubble images that are actually very far from us.
The distance to GN-z11 had been measured in the past by analyzing its color in images snapped with Hubble and the Spitzer Space Telescope. This marks the first time that the Hubble Wide Field camera 3 has been used to offer a precise distance measurement by spectroscopically splitting light from the galaxy into component colors.
This feat marks the first item that the distance of an object so far away has been measured from its spectrum making the distance measurement extremely accurate. The newly measured galaxy is called GN-z11 and while the distant galaxy is very faint, the scientists say that it is unusually bright considering how far it is from Earth. With the discovery of a galaxy this bright, yet so distant from Earth the scientists believe there is evidence of other brighter than expected galaxies in other Hubble images that are actually very far from us.
The distance to GN-z11 had been measured in the past by analyzing its color in images snapped with Hubble and the Spitzer Space Telescope. This marks the first time that the Hubble Wide Field camera 3 has been used to offer a precise distance measurement by spectroscopically splitting light from the galaxy into component colors.
“Our spectroscopic observations reveal the galaxy to be even further away than we had originally thought, right at the distance limit of what Hubble can observe,” explains Gabriel Brammer of the Space Telescope Science Institute and second author of the study.
Before making this measurement, the team of scientists believed that the only way to measure something this distant was to use the James Webb Space Telescope set to launch in the coming years. Scientists use redshift to determine how distant an object is from us and GN-z11 has a redshift of 11.1 corresponding t 400 million years after the Big Bang. The previous distance record was a galaxy called EGSY8p7 with a redshift of 8.68.
+ Hubblecast 90: The Final Frontier (Video)
4. White dwarf lashes red dwarf with mystery ray
Astronomers using ESO’s Very Large Telescope, along with other telescopes on the ground and in space, have discovered a new type of exotic binary star. In the system AR Scorpii we have two orbiting each other stars, away from the Earth about 380 light years. One is the red dwarf with a mass of 1.3 solar masses, and the other is a white dwarf the size of Earth, but 200 thousand. times more massive. But that's not all... In the system AR Scorpii a rapidly spinning white dwarf star powers electrons up to almost the speed of light. These high energy particles release blasts of radiation that lash the companion red dwarf star, and cause the entire system to pulse dramatically every 1.97 minutes with radiation ranging from the ultraviolet to radio.
To know more, read full text: LINK*
+ VIDEO*
5. The great success of Polish astronomers. They confirmed the theory of "hibernation" stars—novae. The studies lasted more than 13 years
This is a breakthrough in the interpretation of the mechanisms leading to gigantic cosmic cataclysms, which are bursts of Nova (A nova, plural - novae or novas). The discovery of the Poles
was presented on the pages of the prestigious scientific magazine
"Nature". These violent but poorly understood events begin with a white
dwarf, the dead remnant of an average star like our Sun, is locked in
tight orbit with a regular, active star.
By:
Cataclysmic variable stars—novae, dwarf novae, and nova-likes—are close binary systems consisting of a white dwarf star (the primary) that is accreting matter from a low-mass companion star (the secondary)1. From time to time such systems undergo large-amplitude brightenings. The most spectacular eruptions, with a ten-thousandfold increase in brightness, occur in classical novae and are caused by a thermonuclear runaway on the surface of the white dwarf2. Such eruptions are thought to recur on timescales of ten thousand to a million years3. In between, the system’s properties depend primarily on the mass-transfer rate: if it is lower than a billionth of a solar mass per year, the accretion becomes unstable and the matter is dumped onto the white dwarf during quasi-periodic dwarf nova outbursts4. The hibernation hypothesis5 predicts that nova eruptions strongly affect the mass-transfer rate in the binary, keeping it high for centuries after the event6. Subsequently, the mass-transfer rate should significantly decrease for a thousand to a million years, starting the hibernation phase. After that the nova awakes again—with accretion returning to the pre-eruption level and leading to a new nova explosion. The hibernation model predicts cyclical evolution of cataclysmic variables through phases of high and low mass-transfer. The theory gained some support from the discovery of ancient nova shells around the dwarf novae Z Camelopardalis7 and AT Cancri8, but direct evidence for considerable mass-transfer changes prior, during and after nova eruptions has not hitherto been found. Here we report long-term observations of the classical nova V1213 Cen (Nova Centauri 2009) covering its pre- and post-eruption phases and precisely documenting its evolution. Within the six years before the explosion, the system revealed dwarf nova outbursts indicative of a low mass-transfer rate. The post-nova is two orders of magnitude brighter than the pre-nova at minimum light with no trace of dwarf nova behaviour, implying that the mass-transfer rate increased considerably as a result of the nova explosion.
Source: LINK*
+ BBC*
Illustration above shows the white dwarf, stealing gas from its partner star and exploding, K Ulaczyk / Warsaw University Observatory, Poland
6. Astronomers spot mysterious objects spewing out gas at a quarter the speed of light
Studying the universe in x-ray wavelengths has allowed astronomers to
peer inside clouds of gas and probe the edges of a black hole’s event
horizon, but there are a few mysteries yet to be solved. In fact,
surveying x-ray sources occasionally results in entirely new,
unexplained phenomena. For example, a pair of objects recently detected
by researchers from the University of Cambridge. These ultra-bright
x-ray sources are blasting out gas at more than a quarter the speed of
light, far faster than should be possible.
Most of the large x-ray sources in the sky are fairly well understood at this point. They’re either supermassive black holes devouring nearby matter, or binary systems with a stellar remnant (white dwarf, neutron star or black hole) pulling material away from a companion star. The friction from the swirling plasma around these objects results in heat and x-ray emissions. These newly discovered objects are an example of a rare third type of x-ray source. They’re an order of magnitude brighter than regular binary sources, and they could have a lot to teach us about the universe.
Astronomers believe these “ultra-luminous x-ray sources” are a different type of binary system that is consuming gas at a much higher rate. The Cambridge team used the ESA’s XMM-Newton space telescope to detect and study the new pair of ultra-luminous sources in galaxies about 22 million light years away from ours. The ultra-luminous sources are called NGC 131 X-1 and NGC 5408 X-1. The data appears to show x-rays being absorbed by the swirling gas before it was ejected from the object at a quarter the speed of light — about 75,000 meters per second or 167 million miles per hour. This is the first time astronomers have been able to observe the “wind” coming off one (let alone two) of these mysterious ultra-luminous objects.
The team is working to nail down the specific nature of these objects, but they’ve got a good handle on how the gas is being blasted out at such a high speed. As matter is pulled inward by gravity, it’s also being pushed out by the radiation emitted by the object. In this case, the pressure exerted by radiation is so high that it overcomes the force of gravity and pushes the gas away. There’s so much radiation relative to gravity that the gas gets moving very fast. This is an application of a concept called Eddington luminosity, which describes the balance between gravity and radiation.
More research will be needed to figure out what exists inside the envelope of super-fast gas surrounding these objects. Right now, the top contenders are either a neutron star or a smallish black hole, both with very large stellar companions.
Most of the large x-ray sources in the sky are fairly well understood at this point. They’re either supermassive black holes devouring nearby matter, or binary systems with a stellar remnant (white dwarf, neutron star or black hole) pulling material away from a companion star. The friction from the swirling plasma around these objects results in heat and x-ray emissions. These newly discovered objects are an example of a rare third type of x-ray source. They’re an order of magnitude brighter than regular binary sources, and they could have a lot to teach us about the universe.
Astronomers believe these “ultra-luminous x-ray sources” are a different type of binary system that is consuming gas at a much higher rate. The Cambridge team used the ESA’s XMM-Newton space telescope to detect and study the new pair of ultra-luminous sources in galaxies about 22 million light years away from ours. The ultra-luminous sources are called NGC 131 X-1 and NGC 5408 X-1. The data appears to show x-rays being absorbed by the swirling gas before it was ejected from the object at a quarter the speed of light — about 75,000 meters per second or 167 million miles per hour. This is the first time astronomers have been able to observe the “wind” coming off one (let alone two) of these mysterious ultra-luminous objects.
The team is working to nail down the specific nature of these objects, but they’ve got a good handle on how the gas is being blasted out at such a high speed. As matter is pulled inward by gravity, it’s also being pushed out by the radiation emitted by the object. In this case, the pressure exerted by radiation is so high that it overcomes the force of gravity and pushes the gas away. There’s so much radiation relative to gravity that the gas gets moving very fast. This is an application of a concept called Eddington luminosity, which describes the balance between gravity and radiation.
More research will be needed to figure out what exists inside the envelope of super-fast gas surrounding these objects. Right now, the top contenders are either a neutron star or a smallish black hole, both with very large stellar companions.
Text by Ryan Whitwam: LINK*
7. Relativistic propulsion using directed energy
Professor Philip M. Lubin from University of California in Santa
Barbara, invented amazing way to give a humanity a huge opportunity to
reach the stars. Called: "Relativistic propulsion using directed energy" = the space drive
(at the beginning) which can provide a small 100kg probe to Mars in
half an hour. Need only a powerful, megawatt laser in Earth orbit, which
its radius hit the small (meter) sail at the probe. The laser beam will
push the probe in a vacuum with great force and give her incredible
speed. It will reach Voyager 1, which recently (after 40 years of
flight) left the Solar System ... in three days, a distance of 1000 AU
(astronomical unit is the distance Earth-Sun) reaches in 12 days, and
the nearest to us star, e.g. Alpha Centauri (4,5 years light of us),
will reach in 15 years. Yet... NASA promised to look at the idea, but in
practice - years flow, and nothing changes. Instead, world-governments work for global war and to change our whole world
into Middle Ages. Why? Because We're too close...???
Full pdf-text about P. Lubin idea: LINK*
Plus His ,UCSB Experimental Cosmology Group': LINK*
8. THE MARS UNDERGROUND [HD] Full Movie
(Where on Mars Should Astronauts Go? - LINK*)
9. Meet the robot ‘mermaid’ which grabs shipwreck treasures
A robot called OceanOne with artificial intelligence and haptic feedback systems gives human pilots an unprecedented ability to explore the depths of the oceans.
Oussama Khatib held his breath as he swam through the wreck of La Lune, over 300 feet below the Mediterranean. The flagship of King Louis XIV sank here in 1664, 20 miles off the southern coast of France, and no human had touched the ruins—or the countless treasures and artifacts the ship once carried—in the centuries since.
With guidance from a team of skilled deep-sea archaeologists who had studied the site, Khatib, a professor of computer science at Stanford, spotted a grapefruit-size vase. He hovered precisely over the vase, reached out, felt its contours and weight, and stuck a finger inside to get a good grip. He swam over to a recovery basket, gently laid down the vase, and shut the lid. Then he stood up and high-fived the dozen archaeologists and engineers who had been crowded around him.
This entire time Khatib had been sitting comfortably in a boat, using a set of joysticks to control OceanOne, a humanoid diving robot outfitted with human vision, haptic force feedback and an artificial brain—in essence, a virtual diver.
When the vase returned to the boat, Khatib was the first person to touch it in hundreds of years. It was in remarkably good condition, though it showed every day of its time underwater: The surface was covered in ocean detritus, and it smelled like raw oysters. The team members were overjoyed, and when they popped bottles of champagne, they made sure to give their heroic robot a celebratory bath.
The expedition to La Lune was OceanOne’s maiden voyage. Based on its astonishing success, Khatib hopes that the robot will one day take on highly skilled underwater tasks too dangerous for human divers, as well as open up a whole new realm of ocean exploration.
“OceanOne will be your avatar,” Khatib says. “The intent here is to have a human diving virtually, to put the human out of harm’s way. Having a machine that has human characteristics that can project the human diver’s embodiment at depth is going to be amazing.”
Meet the robo-mermaid
The concept for OceanOne was born from the need to study coral reefs deep in the Red Sea, far below the comfortable range of human divers. No existing robotic submarine can dive with the skill and care of a human diver, so OceanOne was conceived and built from the ground up, a successful marriage of robotics, artificial intelligence, and haptic feedback systems.
OceanOne looks something like a robo-mermaid. Roughly five feet long from end to end, its torso features a head with stereoscopic vision that shows the pilot exactly what the robot sees, and two fully articulated arms. The “tail” section houses batteries, computers, and eight multi-directional thrusters.
The body looks far unlike conventional boxy robotic submersibles, but it’s the hands that really set OceanOne apart. Each fully articulated wrist is fitted with force sensors that relay haptic feedback to the pilot’s controls, so the human can feel whether the robot is grasping something firm and heavy, or light and delicate. (Eventually, each finger will be covered with tactile sensors.)
The bot’s brain also reads the data and makes sure that its hands keep a firm grip on objects, but that they don’t damage things by squeezing too tightly. In addition to exploring shipwrecks, this makes it adept at manipulating delicate coral reef research and precisely placing underwater sensors.
“You can feel exactly what the robot is doing,” Khatib says. “It’s almost like you are there; with the sense of touch you create a new dimension of perception.”
The pilot can take control at any moment, but most frequently won’t need to lift a finger. Sensors throughout the robot gauge current and turbulence, automatically activating the thrusters to keep the robot in place. And even as the body moves, quick-firing motors adjust the arms to keep its hands steady as it works. Navigation relies on perception of the environment, from both sensors and cameras, and these data run through smart algorithms that help OceanOne avoid collisions. If it senses that its thrusters won’t slow it down quickly enough, it can quickly brace for impact with its arms, an advantage of a humanoid body build.
Dangerous situations
The humanoid form also means that when OceanOne dives alongside actual humans, its pilot can communicate through hand gestures during complex tasks or scientific experiments. Ultimately, though, Khatib designed OceanOne with an eye toward getting human divers out of harm’s way. Every aspect of the robot’s design is meant to allow it to take on tasks that are either dangerous—deep-water mining, oil-rig maintenance, or underwater disaster situations like the Fukushima Daiichi power plant—or simply beyond the physical limits of human divers.
“We connect the human to the robot in very intuitive and meaningful way. The human can provide intuition and expertise and cognitive abilities to the robot,” Khatib says. “The two bring together an amazing synergy. The human and robot can do things in areas too dangerous for a human, while the human is still there.”
Khatib was forced to showcase this attribute while recovering the vase. As OceanOne swam through the wreck, it wedged itself between two cannons. Firing the thrusters in reverse wouldn’t extricate it, so Khatib took control of the arms, motioned for the bot to perform a sort of pushup, and OceanOne was free.
Next month, OceanOne will return to the Stanford campus, where Khatib and his students will continue iterating on the platform. The prototype robot is a fleet of one, but Khatib hopes to build more units, which would work in concert during a dive.
The expedition to La Lune was made possible in large part thanks to the efforts of Michel L’Hour, the director of underwater archaeology research in France’s Ministry of Culture. Previous remote studies of the shipwreck conducted by L’Hour’s team made it possible for OceanOne to navigate the site. Vincent Creuze of the Universite de Montpellier in France commanded the support underwater vehicle that provided third-person visuals of OceanOne and held its support tether at a safe distance.
In addition to Stanford, Meka Robotics and the King Abdullah University of Science and Technology (KAUST) in Saudi Arabia supported the robot’s development.
Source from Stanford University: LINK*
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Part I of Science News - HERE*
Part II of Science News - HERE*
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