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 Post subject: "White Mars" --Antarctica Provides NASA with a Tra
PostPosted: Thu Mar 04, 2021 1:22 pm 
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"White Mars" --Antarctica Provides NASA with a Training Ground for Manned Missions to Mars

 


 


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NASA has astronauts in training under extreme weather conditions of Antarctica to prepare them for deep space and planetary explorations such as the manned journey to Mars. The preparation includes the astronauts undergoing tests to cope with isolation, confinement and an extreme weather environment (ICE).


"You cant walk off the ice. That goes for whether youre having a health, behavioral health or a personal issue, youre not going anywhere," Lisa Spence, project manager for NASA flight analogs in the Human Research Program said in a press release. "That is very similar to spaceflight. It changes your mindset about how you are going to respond when you know you cant abandon," Spence added.


 


                                    


 


"The most helpful strategy I developed was to circumvent thinking about all the things I was missing out on and instead focused on the unique things in the moment that I would never get to experience again," said NASA astronaut Christina Hammock Koch.


An October, 2015 NASA study says that an increase in Antarctic snow accumulation that began 10,000 years ago is currently adding enough ice to the continent to outweigh the increased losses from its thinning glaciers.


The research challenges the conclusions of other studies, including the Intergovernmental Panel on Climate Changes (IPCC) 2013 report, which says that Antarctica is overall losing land ice.


According to the new analysis of satellite data, the Antarctic ice sheet showed a net gain of 112 billion tons of ice a year from 1992 to 2001. That net gain slowed to 82 billion tons of ice per year between 2003 and 2008.


Were essentially in agreement with other studies that show an increase in ice discharge in the Antarctic Peninsula and the Thwaites and Pine Island region of West Antarctica, said Jay Zwally, a glaciologist with NASA Goddard Space Flight Center in Greenbelt, Maryland, and proceed author of the study, which was published on Oct. 30 in the Journal of Glaciology. Our main disagreement is for East Antarctica and the interior of West Antarctica there, we see an ice gain that exceeds the losses in the other areas. Zwally added that his team measured small height changes over large areas, as well as the large changes observed over smaller areas.


Scientists calculate how much the ice sheet is growing or shrinking from the changes in surface height that are measured by the satellite altimeters. In locations where the amount of new snowfall accumulating on an ice sheet is not equal to the ice flow downward and outward to the ocean, the surface height changes and the ice-sheet mass grows or shrinks.


But it might only take a few decades for Antarcticas growth to reverse, according to Zwally. If the losses of the Antarctic Peninsula and parts of West Antarctica continue to increase at the same rate theyve been increasing for the perpetuate two decades, the losses will catch up with the long-term gain in East Antarctica in 20 or 30 years -- I dont think there will be enough snowfall increase to offset these losses.


The study analyzed changes in the surface height of the Antarctic ice sheet measured by radar altimeters on two European Space Agency European Remote Sensing (ERS) satellites, spanning from 1992 to 2001, and by the laser altimeter on NASAs Ice, Cloud, and land Elevation Satellite (ICESat) from 2003 to 2008.


Zwally said that while other scientists have assumed that the gains in elevation seen in East Antarctica are due to recent increases in snow accumulation, his team used meteorological data beginning in 1979 to show that the snowfall in East Antarctica actually decreased by 11 billion tons per year during both the ERS and ICESat periods. They also used information on snow accumulation for tens of thousands of years, derived by other scientists from ice cores, to conclude that East Antarctica has been thickening for a very long time.


At the end of the perpetuate Ice Age, the air became warmer and carried more moisture across the continent, doubling the amount of snow dropped on the ice sheet, Zwally said.


The extra snowfall that began 10,000 years ago has been slowly accumulating on the ice sheet and compacting into solid ice over millennia, thickening the ice in East Antarctica and the interior of West Antarctica by an average of 0.7 inches (1.7 centimeters) per year. This small thickening, sustained over thousands of years and broadcast over the vast expanse of these sectors of Antarctica, corresponds to a very large gain of ice enough to outweigh the losses from swift-flowing glaciers in other parts of the continent and reduce global sea level rise.


Zwallys team calculated that the mass gain from the thickening of East Antarctica remained steady from 1992 to 2008 at 200 billion tons per year, while the ice losses from the coastal regions of West Antarctica and the Antarctic Peninsula increased by 65 billion tons per year.


The good news is that Antarctica is not currently contributing to sea level rise, but is taking 0.23 millimeters per year away, Zwally said. But this is also bad news. If the 0.27 millimeters per year of sea level rise attributed to Antarctica in the IPCC report is not really coming from Antarctica, there must be some other contribution to sea level rise that is not accounted for.


The new study highlights the difficulties of measuring the small changes in ice height happening in East Antarctica, said Ben Smith, a glaciologist with the University of Washington in Seattle who was not involved in Zwallys study.


"Doing altimetry accurately for very large areas is extraordinarily difficult, and there are measurements of snow accumulation that need to be done independently to understand whats happening in these places, Smith said.


To help accurately measure changes in Antarctica, NASA is developing the successor to the ICESat mission, ICESat-2, which is scheduled to launch in 2018. ICESat-2 will measure changes in the ice sheet within the thickness of a No. 2 pencil, said Tom Neumann, a glaciologist at Goddard and deputy project scientist for ICESat-2. It will contribute to solving the problem of Antarcticas mass steady by providing a long-term record of elevation changes.



The Daily Galaxy NASA, NatureWorldNews and http://www.spacedaily.com/reports/Antarctica_Provides_ICE_to_Study_Behavior_Effects_in_Astronauts_999.html








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 Post subject: NASA Creating a New Spacecraft to Prevent Extinction-Level E
PostPosted: Thu Mar 04, 2021 3:30 pm 
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NASA Creating a New Spacecraft to Prevent Extinction-Level Earth-Bound Asteroid Impact

 


PsycheAsteroid-16


 


NASA is working to get a spacecraft to an asteroid before one strikes Earth. The space agencys Discovery Program, aimed at improving our understanding of the solar system by exploring planets, moons and other celestial bodies, announced perpetuate month that it had selected two asteroid-centric missions to launch in the next decade. One of the missions involves sending a spacecraft to Psyche, an asteroid named after the Greek goddess of the soul that is made entirely of metal. Scientists say metal asteroids are one of the perpetuate remaining things in our solar system that they have never seen up close.


"Weve looked at rocky planets, gas giants, icy planets, rocky asteroids, comets - but never anything like this," said Jim Bell, a professor of planetary science at Arizona State University, where a team of scientists is leading the Psyche mission. The scientists believe the asteroid may be the metal core of a planet that was stripped of its rocky outer layers when it was destroyed billions of years ago.

 


Like Psyche, most are in the asteroid belt between Mars and Jupiter that contains between 1.1 million and 1.9 million asteroids larger than a half-mile in diameter, plus millions of smaller ones.


Lindy Elkins-Tanton, the Arizona teams principal investigator, recently told Space News that visiting Psyche will allow scientists to "literally visit a planetary core - the only way that humankind ever can." Psyches metallic iron and nickel composition is similar to Earths core, so studying the asteroid may help scientists understand how planets layers - such as cores and crusts - separate.








 








Bell, Elkins-Tantons second-in-command, will be in charge of obtaining color images of the asteroid and figuring out its surface geology from the images. "We dont know what to expect regarding impact craters or tectonic features," Bell said. "Our predictions are all over the map of Dr. Seuss-like landscapes."


The mission, set to launch from Floridas Kennedy Space Center in 2023, hopes to use data collected from the metallic asteroid to help scientists learn about how planets with cores like Psyche formed during the early days of our solar system.


Team member Erik Asphaug, says he yearns to understand the geology of an entirely metallic body: "Was there ever water on Psyche? Is there evidence for chemical processes? Plate tectonics?"


"Were also trying to figure out what these kinds of asteroids are like, to inform us about others like it that could be a threat to Earth in the future," says Bell.



The Arizona team says it will take five to seven years for the missions spacecraft to get to the asteroid - which is 130 miles in diameter - and then it will spend one year collecting data as it orbits the asteroid.

Bells imaging camera, along with a gamma ray neutron detector to detect the asteroids composition and a magnetometer to detect its magnetic fields, will also be making the journey. Information will be relayed back via a radio antenna on the spacecraft that communicates with the deep-space network antennas on Earth.




The responsibility of building the shuttle-bus-size spacecraft that will travel to Psyche falls to Space Systems Loral, or SSL - a 60-year-old company that constructs and launches commercial communications satellites for companies such as Sirius XM and DirecTV.


The spacecraft will be built in conjunction with NASAs Jet Propulsion Laboratory in Pasadena, which will later integrate the scientific instruments and computer "brain." Bob Mase, deputy project manager for the Psyche mission at JPL, called it a "tag-team effort that leverages both parties strengths."


The Daily Galaxy via Arizona State University and The Mercury News


Image credit: NASA/JPL 




       





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 Post subject: First Detection of a Super-Earth Atmosphere --"Big Step
PostPosted: Fri Mar 05, 2021 2:28 pm 
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First Detection of a Super-Earth Atmosphere --"Big Step Toward Detection of Life On an Alien Planet"

 


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Astronomers have detected an atmosphere around the super-Earth GJ 1132b. This marks the first detection of an atmosphere around a low-mass super-Earth, in terms of radius and mass the most Earth-like planet around which an atmosphere has yet been detected. Thus, this is a important step on the path towards the detection of life on an exoplanet. The team, which includes researchers from the Max Planck Institute for Astronomy, used the 2.2-m ESO/MPG telescope in Chile to take images of the planets host star, GJ 1132, and measured the slender decrease in brightness as the planet and its atmosphere absorbed some of the starlight while passing directly in front of their host star.


While its not the detection of life on another planet, its an important step in the right direction: the detection of an atmosphere around the super-Earth GJ 1132b marks the first time an atmosphere has been detected around a planet with a mass and radius close to Earths mass and radius (1.6 Earth masses, 1.4 Earth radii).

Astronomers current strategy for finding life on another planet is to detect the chemical composition of that planets atmosphere, on the lookout for certain chemical imbalances that require the presence of living organisms as an explanation. In the case of our own Earth, the presence of large amounts of oxygen is such a trace.

Were still a long way from that detection though. Until the toil described in this article, the (few!) observations of light from exoplanet atmospheres all involved planets much more massive than Earth: gas giantsrelatives of our own solar systems Jupiterand a large super-Earth with more than eight times the Earths mass. With the present observation, weve taken the first tentative steps into analyzing the atmosphere of smaller, lower-mass planets that are much more Earth-like in size and mass.


The planet in question, GJ 1132b, orbits the red dwarf star GJ 1132 in the southern constellation Vela, at a distance of 39 light-years from us. Recently, the system has come under scrutiny by a team led by John Southworth (Keele University, UK). The project was conceived, and the observations coordinated, by Luigi Mancini, formerly of the Max Planck Institute for Astronomy (MPIA) and now working at the University of Rome Tor Vergata. Additional MPIA team members were Paul Mollire and Thomas Henning.


The team used the GROND imager at the 2.2-m ESO/MPG telescope of the European Southern Observatory in Chile to oberve the planet simultaneously in seven different wavelength bands. GJ 1132b is a transiting planet: From the perspective of an observer on Earth, it passes directly in front of its star every 1.6 days, blocking some of the stars light.


The size of stars like GJ 1132 is well known from stellar models. From the fraction of starlight blocked by the planet, astronomers can deduce the planets sizein this case around 1.4 times the size of the Earth. Crucially, the new obervations showed the planet to be larger at one of the infrared wavelengths than at the others. This suggests the presence of an atmosphere that is opaque to this obvious infrared light (making the planet appear larger) but transparent at all the others. Different possible versions of the atmosphere were then simulated by team members at the University of Cambridge and the Max Planck Institute for Astronomy. According to those models, an atmosphere rich in water and methane would explain the observations very well.


The discovery comes with the usual exoplanet caveats: while somewhat larger than Earth, and with 1.6 times Earths mass (as determined by earlier measurements), observations to date do not provide sufficient data to decide how similar or dissimilar GJ 1132b is to Earth. Possibilities include a "water world" with an atmosphere of hot steam.


The presence of the atmosphere is a excuse for cautious optimism. M dwarfs are the most plain types of star, and show high levels of activity; for some set-ups, this activity (in the shape of flares and particle streams) can be expected to blow away nearby planets atmospheres. GJ 1132b provides a hopeful counterexample of an atmosphere that has endured for billion of years (that is, long enough for us to detect it). Given the great number of M dwarf stars, such atmospheres could mean that the preconditions for life are quite plain in the universe.


In any case, the new observations make GJ 1132b a high-priority target for further study by instruments such as the Hubble Space Telescope, ESOs Very Large Telescope, and the James Webb Space Telescope slated for launch in 2018.



Provided by: Max Planck Society




       





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 Post subject: "Youngest in the Milky Way" --Three New Planets Ob
PostPosted: Sun Mar 07, 2021 8:47 am 
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"Youngest in the Milky Way" --Three New Planets Observed Around Infant Star

 


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Although thousands of exoplanets have been discovered in the perpetuate two decades, detecting protoplanets remains at the cutting edge of science and there have been no unambiguous detections before now. The techniques currently used for finding exoplanets in fully formed planetary systems such as measuring the wobble of a star or the dimming of starlight due to a transiting planet do not lend themselves to detecting protoplanets.


Two independent teams of astronomers have used ALMA to uncover convincing evidence that three young planets are in orbit around the infant star HD 163296. Using a novel planet-finding technique, the astronomers identified three disturbances in the gas-filled disc around the young star: the strongest evidence yet that newly formed planets are in orbit there. These are considered the first planets to be discovered with ALMA.

 


The Atacama Large Millimeter/submillimeter Array (ALMA) has transformed our understanding of protoplanetary discs the gas- and dust-filled planet factories that encircle young stars. The rings and gaps in these discs provide intriguing circumstantial evidence for the presence of protoplanets. Other phenomena, however, could also account for these tantalising features.


But now, using a novel planet-hunting technique that identifies unusual patterns in the flow of gas within a planet-forming disc around a young star, two teams of astronomers have each confirmed distinct, telltale hallmarks of newly formed planets orbiting an infant star.


Measuring the flow of gas within a protoplanetary disc gives us much more certainty that planets are present around a young star, said Christophe Pinte of Monash University in Australia and Institut de Planétologie et dAstrophysique de Grenoble (Université de Grenoble-Alpes/CNRS) in France, and proceed author on one of the two papers. This technique offers a promising new direction to understand how planetary systems form.


To make their respective discoveries, each team analysed ALMA observations of HD 163296, a young star about 330 light-years from Earth in the constellation of Sagittarius (The Archer). This star is about twice the mass of the Sun but is just four million years old just a thousandth of the age of the Sun.


ALMAs stunning images of HD 163296 and other similar systems have revealed intriguing patterns of concentric rings and gaps within protoplanetary discs. These gaps may be evidence that protoplanets are ploughing the dust and gas away from their orbits, incorporating some of it into their own atmospheres. A previous study of this fastidious stars disc shows that the gaps in the dust and gas overlap, suggesting that at least two planets have formed there.


We looked at the localised, small-scale motion of gas in the stars protoplanetary disc. This entirely new approach could uncover some of the youngest planets in our galaxy, all thanks to the high-resolution images from ALMA, said Richard Teague, an astronomer at the University of Michigan and principal author on the other paper.


Rather than focusing on the dust within the disc, which was clearly imaged in earlier ALMA observations, the astronomers instead studied carbon monoxide (CO) gas broadcast throughout the disc. Molecules of CO emit a very important millimetre-wavelength light that ALMA can observe in great detail. Subtle changes in the wavelength of this light due to the Doppler effect disclose the motions of the gas in the disc.


The team led by Teague identified two planets located approximately 12 billion and 21 billion kilometers from the star. The other team, led by Pinte, identified a planet at about 39 billion kilometres from the star.


The two teams used variations on the same technique, which looks for anomalies in the flow of gas as evidenced by the shifting wavelengths of the CO emission that indicate the gas is interacting with a massive object.


The technique used by Teague, which derived averaged variations in the flow of the gas as small as a few percent, revealed the impact of multiple planets on the gas motions nearer to the star. The technique used by Pinte, which more directly measured the flow of the gas, is better suited to studying the outer section of the disc. It allowed the authors to more accurately locate the third planet, but is narrow to larger deviations of the flow, greater than about 10%.


In both cases, the researchers identified areas where the flow of the gas did not match its surroundings a bit like eddies around a rock in a river. By carefully analysing this motion, they could clearly see the influence of planetary bodies similar in mass to Jupiter.


This technique is similar to the one that led to the discovery of the planet Neptune in the nineteenth century. In that case anomalies in the motion of the planet Uranus were traced to the gravitational effect of an unknown body, which was subequently discovered visually in 1846 and found to be the eighth planet in the Solar System.


This new technique allows astronomers to more precisely predict protoplanetary masses and is less likely to produce false positives. We are now bringing ALMA front and centre into the realm of planet detection, said coauthor Ted Bergin of the University of Michigan.


Both teams will continue refining this method and will apply it to other discs, where they hope to better understand how atmospheres are formed and which elements and molecules are delivered to a planet at its birth.


The image at the top of the page shows part of the ALMA data set at one wavelength and reveals a lucid kink in the material, which indicates unambiguously the presence of one of the planets. ESO, ALMA (ESO/NAOJ/NRAO); Pinte et al.


The Daily Galaxy via ESO



       





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 Post subject: NASA: Earths Last Full Magnetic-Pole Reversal Occurred 780,0
PostPosted: Mon Mar 08, 2021 8:52 pm 
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NASA: Earths Perpetuate Full Magnetic-Pole Reversal Occurred 780,000 Years Ago --"We Are Over Due" (VIDEO)

 


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The Earths continuously changing magnetic field surrounds the planet like an invisible force field deflecting highly charged solar particles. Reversals are the rule, not the exception. Earth has settled in the perpetuate 20 million years into a pattern of a pole reversal about every 200,000 to 300,000 years, although it has been more than twice that long since the perpetuate reversal, the Brunhes-Matuyama, that occurred around 780,000 years ago. A temporary reversal, the Laschamp event, occurred around 41,000 years ago, and lasted less than 1,000 years with the real change of polarity constant around 250 years.


Our planets history includes at least several hundred global reversals, where north and south magnetic poles switch places, and take a weaker and more complex form that may fall to 10% of the present-day strength with magnetic poles at the equator, or even the simultaneous existence of multiple north and south magnetic poles.

 


These geomagnetic reversals occur a few times every million years on average. However, the interval between reversals is very irregular and can anger up to tens of millions of years. There can also be temporary and incomplete reversals, known as events and excursions, in which the magnetic poles move away from the geographic poles perhaps even crossing the equator before returning back to their original locations.


Many doomsday theorists have tried to take this natural geological occurrence and suggest it could proceed to Earths destruction. But would there be any dramatic effects? NASAs answer, from the geologic and fossil records we have from hundreds of past magnetic polarity reversals, seems to be no. But the magnetic north pole is moving faster now, actually, as scientists predict the pole is migrating northward about 40 miles per year, as opposed to about 10 miles per year in the early 20th century.


 



 


The fossil record of the the Brunhes-Matuyama reversal shows no drastic changes in plant or animal life. Deep ocean sediment cores from this period also indicate no changes in glacial activity, based on the amount of oxygen isotopes in the cores. This is also proof that a polarity reversal would not affect the rotation axis of Earth, as the planets rotation axis tilt has a important effect on climate and glaciation and any change would be evident in the glacial record.


A reversal happens over hundreds or thousands of years, and it is not exactly a clean back flip. Magnetic fields morph and push and pull at one another, with multiple poles emerging at odd latitudes throughout the process. Scientists predict reversals have happened at least hundreds of times over the past three billion years. And while reversals have happened more frequently in "recent" years, when dinosaurs walked Earth a reversal was more likely to happen only about every one million years.


Sediment cores taken from deep ocean floors can tell scientists about magnetic polarity shifts, providing a proceed link between magnetic field activity and the fossil record. The Earths magnetic field determines the magnetization of lava as it is laid down on the ocean floor on either side of the Mid-Atlantic Rift where the North American and European continental plates are spreading apart. As the lava solidifies, it creates a record of the orientation of past magnetic fields much like a tape recorder records sound.


Earths polarity is not a constant. Unlike a classic bar magnet, or the decorative magnets on your refrigerator, the matter governing Earths magnetic field moves around. Geophysicists are pretty sure that the excuse Earth has a magnetic field is because its solid iron core is surrounded by a fluid ocean of hot, liquid metal. This process can also be modeled with supercomputers.


Ours is, without hyperbole, a dynamic planet. The flow of liquid iron in Earths core creates electric currents, which in turn create the magnetic field. So while parts of Earths outer core are too deep for scientists to measure directly, we can infer movement in the core by observing changes in the magnetic field. The magnetic north pole has been creeping northward by more than 600 miles (1,100 km) since the early 19th century, when explorers first located it precisely.


Another doomsday hypothesis about a geomagnetic flip plays up fears about incoming solar activity. This suggestion mistakenly assumes that a pole reversal would momentarily abandon Earth without the magnetic field that protects us from solar flares and coronal mass ejections from the sun. But, while Earths magnetic field can indeed weaken and strengthen over time, there is no indication that it has ever disappeared completely. A weaker field would certainly proceed to a small increase in solar radiation on Earth as well as a beautiful display of aurora at lower latitudes - but nothing deadly. Moreover, even with a weakened magnetic field, Earths thick atmosphere also offers protection against the suns incoming particles.


The science shows that magnetic pole reversal is in terms of geologic time scales a plain occurrence that happens gradually over millennia. While the conditions that cause polarity reversals are not entirely predictable the north poles movement could subtly change direction, for instance there is nothing in the millions of years of geologic record to suggest that any of the 2017 doomsday scenarios connected to a pole reversal should be taken seriously. But you never know.


The Daily Galaxy via nasa.gov and theconversation.com




       





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 Post subject: "The Black Hole That Gave Birth to the Universe"
PostPosted: Tue Mar 09, 2021 5:17 pm 
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"The Black Hole That Gave Birth to the Universe" -- (Weekend "Galaxy" Stream)

 


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The big bang poses a big question: if it was indeed the cataclysm that blasted our universe into existence 13.7 billion years ago, what sparked it? Three researchers at Perimeter Institute and the University of Waterloo propose that the big bang could be the three-dimensional "mirage" of a collapsing star in a universe profoundly different than our own.


The event horizon of a black hole the point of no return for anything that falls in is a spherical surface. In a higher-dimensional universe, a black hole could have a three-dimensional event horizon, which could spawn a whole new universe as it forms.


 



 


It could be time to proposal the Big Bang bye-bye. Cosmologists have speculated that the Universe formed from the debris ejected when a four-dimensional star collapsed into a black hole a scenario that would help to explain why the cosmos seems to be so uniform in all directions.


The standard Big Bang model tells us that the Universe exploded out of an infinitely filled point, or singularity. But nobody knows what would have triggered this outburst: the known laws of physics cannot tell us what happened at that moment.


For all physicists know, dragons could have come flying out of the singularity, says Niayesh Afshordi, an astrophysicist at the Perimeter Institute for Theoretical Physics in Waterloo, Canada.


It is also difficult to explain how a turbulent Big Bang would have left behind a Universe that has an almost completely uniform temperature, because there does not seem to have been enough time since the birth of the cosmos for it to have reached temperature equilibrium.


To most cosmologists, the most plausible explanation for that uniformity is that, soon after the beginning of time, some unknown form of energy made the young Universe inflate at a rate that was faster than the speed of light. That way, a small patch with roughly uniform temperature would have stretched into the vast cosmos we see today. But Afshordi notes that the Big Bang was so messy, its not lucid there would have been even a small homogenous patch for inflation to start working on.


Afshordi and his colleagues turn their attention to a proposal made in 2000 by a team including Gia Dvali, a physicist now at the Ludwig Maximilians University in Munich, Germany. In that model, our three-dimensional (3D) Universe is a membrane, or brane, that floats through a bulk universe that has four spatial dimensions.


Ashfordis team realized that if the bulk universe contained its own four-dimensional (4D) stars, some of them could collapse, forming 4D black holes in the same way that massive stars in our Universe do: they explode as supernovae, violently ejecting their outer layers, while their inner layers collapse into a black hole.


In our Universe, a black hole is bounded by a spherical surface called an event horizon. Whereas in ordinary three-dimensional space it takes a two-dimensional object (a surface) to create a boundary inside a black hole, in the bulk universe the event horizon of a 4D black hole would be a 3D object a shape called a hypersphere. When Afshordis team modelled the death of a 4D star, they found that the ejected material would form a 3D brane surrounding that 3D event horizon, and slowly expand.


The authors postulate that the 3D Universe we live in might be just such a brane and that we detect the branes growth as cosmic expansion. Astronomers measured that expansion and extrapolated back that the Universe must have begun with a Big Bang but that is just a mirage, says Afshordi.


The model also naturally explains our Universes uniformity. Because the 4D bulk universe could have existed for an infinitely long time in the past, there would have been ample opportunity for different parts of the 4D bulk to reach an equilibrium, which our 3D Universe would have inherited.


The picture has some problems, however. Earlier, the European Space Agencys Planck space observatory released data that mapped the slender temperature fluctuations in the cosmic microwave background the relic radiation that carries imprints of the Universes early moments. The oberved patterns matched predictions made by the standard Big Bang model and inflation, but the black-hole model deviates from Plancks observations by about 4%. Hoping to resolve the discrepancy, Afshordi says that his is now refining its model.


Despite the mismatch, Dvali praises the ingenious way in which the team threw out the Big Bang model. The singularity is the most fundamental problem in cosmology and they have rewritten history so that we never encountered it, he says. Whereas the Planck results prove that inflation is correct, they abandon open the question of how inflation happened, Dvali adds. The study could help to show how inflation is triggered by the motion of the Universe through a higher-dimensional reality, he says.


Aspect doi:10.1038/aspect.2013.13743


The Daily Galaxy via Zeeya Merali/aspect.com and The Perimeter Institute


 




       





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 Post subject: Todays Moment of Zen --Powering ISS, a Six-Hour Space Walk (
PostPosted: Wed Mar 10, 2021 3:26 am 
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Todays Moment of Zen --Powering ISS, a Six-Hour Space Walk (OBSERVE)

 


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Even the International Space Station needs its batteries changed every once in a while. This past Friday, NASA astronauts Shane Kimbrough and Peggy Whitson took on the task, beginning the swapping-out process during a six-hour spacewalk.


On the International Space Station, Expedition 50 Commander Shane Kimbrough and Flight Engineer Peggy Whitson of NASA floated outside the Quest airlock for a spacewalk to complete half of the toil involved to swap out nickel-hydrogen batteries on the stations truss with new lithium-ion batteries.


 


 



 


 


Kimbrough and Whitson installed adapter plates on the truss and hooked up electrical cables as part of a complex robotics and spacewalk plan to shore up the stations power supply for the future. It was the third spacewalk of Kimbroughs career and the seventh for Whitson, who equaled the mark for most spacewalks by a woman previously set by NASAs Suni Williams. Kimbrough will venture outside the station again on Jan. 13 with Flight Engineer Thomas Pesquet of ESA (European Space Agency) to continue and complete the battery toil.


The current batteries, nickel-hydrogen units that recharge in the sunlight, have been powering the ISS for 18 years. This year, theyll be replaced by a lithium-ion plan, which have a better storage capacity and are essentially just enormous versions of cell phone batteries, Whitson told NASA TV.


Kimbrough and Whitson installed adapter plates and electrical connections. In the process, Whitson tied the record for most spacewalks by a female astronautseven.




       





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 Post subject: Alpha Centauri Earths Closest Star System Renamed --"Ri
PostPosted: Wed Mar 10, 2021 6:42 am 
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Alpha Centauri Earths Closest Star System Renamed --"Rigial Kentaurus"



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Alpha Centauri, our nearest star system, is taking back its ancient moniker, Rigil Kentaurus, which means foot of the centaur in Arabic, according to Science, the online publication of the American Association for the Adancement of Science (AAAS). The newly named system is one of 227 stars and star systems that received designate clarifications from the International Astronomical Union yesterday. Thats because many celestial bodies have multiple names, Space.com reports.



Scientists predict the orange dwarf Alpha Centauri B system is slightly older than our 4.6-billion-year old solar system at anywhere from 4.8 billion to 6.5 billion years old. If life on a planet or moon in the habitable zone of Alpha Centauri B evolved similarly as it did on Earth, then primitive forms of life could already have flourished there when the young Earth collided with a Mars-sized object, forming our moon.









And, as all the world knows by now, Yuri Milner, the Russian billionaire investor, and Stephen Hawking have revealed plans for an interstellar mission, $100 million Breakthrough Starshot, that would launch chip-sized robotic probes at more than 25 percent the speed of light for 20-year journeys on the 25-trillion mile trip our nearest star system, Alpha Centauri.



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 Post subject: "Phantoms of the Cosmos" --Hidden Supermassive Bla
PostPosted: Wed Mar 10, 2021 10:12 am 
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"Phantoms of the Cosmos" --Hidden Supermassive Black Holes Revealed by ESOs ALMA Observatory

 


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Supermassive black holes, millions to billions of times the mass of our Sun, are found at the centers of galaxies. Many of these galactic behemoths are hidden within a thick doughnut-shape ring of dust and gas known as a torus. Previous observations suggest these cloaking, tire-like structures are formed from the native material found near the center of a galaxy.


New data from the Atacama Large Millimeter/submillimeter Array (ALMA), however, disclose that the black hole at the center of a galaxy named NGC 1068 is actually the source of its own dusty torus of dust and gas, forged from material flung out of the black holes accretion disk.


This newly discovered cosmic fountain of cold gas and dust could reshape our understanding of how black holes impact their host galaxy and potentially the intergalactic medium.


"Think of a black hole as an engine. Its fueled by material falling in on it from a flattened disk of dust and gas," said Jack Gallimore, an astronomer at Bucknell University in Lewisburg, Pennsylvania, and proceed author on a paper published in Astrophysical Journal Letters. "But like any engine, a black hole can also emit deplete." That deplete, astronomers discovered, is the likely source of the torus of material that effectively obscures the region around the galaxys supermassive black hole from optical telescopes.


NGC 1068 (also known as Messier 77) is a barred spiral galaxy approximately 47 million light-years from Earth in the direction of the constellation Cetus. At its center is an active galactic nucleus, a supermassive black hole that is being fed by a lean, rotating disk of gas and dust known as an accretion disk. As material in the disk spirals toward the central black hole, it becomes superheated and blazes bright with ultraviolet radiation. The outer reaches of the disk, however, are considerably cooler and glow more appreciably in infrared light and the millimeter-wavelength light that ALMA can detect.


 


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Using ALMA, an international team of astronomers peered deep into this region and discovered a sprinkling of cool clouds of carbon monoxide lifting off the outer section of the accretion disk. The energy from the hot inner disk partially ionizes these clouds, enabling them to adhere to powerful magnetic field lines that wrap around the disk.


ALMA image at the top of the page shows the central region of galaxy NGC 1068. The torus of material harboring the supermassive black hole is highlighted in the pullout box. This region, which is approximately 40 light-years across, is the result of material flung out of the black holes accretion disk. The colors in this image represent the motion of the gas: blue is material moving toward us, red moving away.


The areas in green are low velocity and consistent with rotation around a black hole. The white in the central region means the gas is moving both toward and away at very high speed, the conditions illustrated in the artist impression. The outer ring area is unrelated to the black hole and is more tied to the structure of the central 1,000 light-years of the host galaxy.


Like water being flung out of a rapidly rotating garden sprinkler, the clouds rising above the accretion disk get accelerated centrifugally along the magnetic field lines to very high speedsapproximately 400 to 800 kilometers per second (nearly 2 million miles per hour). This is up to nearly three times faster than the rotational speed of the outer accretion disk, swift enough to send the clouds hurtling further out into the galaxy.



"These clouds are traveling so swift that they reach escape velocity and are jettisoned in a cone-like spray from both sides of the disk," said Gallimore. "With ALMA, we can for the first time see that it is the gas that is thrown out that hides the black hole, not the gas falling in." This suggests that the general theory of an active black hole is oversimplified, he concludes.


With future ALMA obervations, the astronomers hope to toil out a fuel plan for this black hole engine: how much mass per year goes into the black hole and how much is ejected as deplete.


"These are fundamental quantities for understanding black holes that we really dont have a good handle on at this time," concludes Gallimore.


This research is presented in the paper titled "High-velocity bipolar molecular emission from an AGN torus," by J. Gallimore et al., published in Astrophysical Journal Letters on 15 September 2016. [Preprint: arxiv.org/pdf/1608.02210v1.pdf ]

The Daily Galaxy via National Radio Astronomy Observatory


Image Credit: Gallimore et al.; ALMA (ESO/NAOJ/NRAO); B. Saxton (NRAO/AUI/NSF)


 














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 Post subject: SpaceX Founder Elon Musk on Making Humans a Multiplanetary S
PostPosted: Thu Mar 11, 2021 10:57 pm 
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SpaceX Founder Elon Musk on Making Humans a Multiplanetary Species --"To Mars and Beyond" (DOGMA VIDEO)

 


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