The finding suggests that quasars—the brilliant cores of active galaxies – may commonly host two central supermassive black holes, which fall into orbit about one another as a result of the merger between two galaxies. Like a pair of whirling skaters, the black-hole duo generates tremendous amounts of energy that makes the core of the host galaxy outshine the glow of its population of billions of stars, which scientists then identify as quasars.
Scientists looked at Hubble archival observations of ultraviolet radiation emitted from the center of Mrk 231 to discover what they describe as “extreme and surprising properties.”
If only one black hole were present in the center of the quasar, the whole accretion disk made of surrounding hot gas would glow in ultraviolet rays. Instead, the ultraviolet glow of the dusty disk abruptly drops off toward the center. This provides observational evidence that the disk has a big donut hole encircling the central black hole. The best explanation for the donut hole in the disk, based on dynamical models, is that the center of the disk is carved out by the action of two black holes orbiting each other. The second, smaller black hole orbits in the inner edge of the accretion disk, and has its own mini-disk with an ultraviolet glow.
Read more ~ NASA.gov
Image: This artistic illustration is of a binary black hole found in the center of the nearest quasar to Earth, Markarian 231. Credits: NASA, ESA, and G. Bacon (STScI)
Youngster Galaxy Magnified by Abell 383
Hubble was first to spot this galaxy, one of the youngest in the distant universe. Its stars formed 13.5 billion years ago, a mere 200 million years after the Big Bang. The galaxy’s image is magnified by the gravity of a massive cluster of galaxies (Abell 383) parked in front of it, making it appear eleven times brighter. This phenomenon is called gravitational lensing.
Image Credit: NASA, ESA, J. Richard (Centre for Astronomical Research/Observatory of Lyon, France), and J.-P Kneib (Astrophysical Laboratory of Marseille, France).
NASA Astronomy Picture of the Day 2016 February 11
Gravitational radiation has been directly detected. The first-ever detection was made by both facilities of the Laser Interferometer Gravitational-Wave Observatory (LIGO) in Washington and Louisiana simultaneously last September. After numerous consistency checks, the resulting 5-sigma discovery was published today. The measured gravitational waves match those expected from two large black holes merging after a death spiral in a distant galaxy, with the resulting new black hole momentarily vibrating in a rapid ringdown.
A phenomenon predicted by Einstein, the historic discovery confirms a cornerstone of humanity’s understanding of gravity and basic physics. It is also the most direct detection of black holes ever. The featured illustration depicts the two merging black holes with the signal strength of the two detectors over 0.3 seconds superimposed across the bottom. Expected future detections by Advanced LIGO and other gravitational wave detectors may not only confirm the spectacular nature of this measurement but hold tremendous promise of giving humanity a new way to see and explore our universe.
The Science of Balloon Popping: Fragmentation vs. Opening.
Soon to be published in Physical Review Letters, the research identifies how differing levels of stress affect rubber and latex.
The first depicts a moderately inflated balloon that splits uniformly into two pieces.
The second depicts a highly inflated balloon that is under a larger level of stress, which fragments into smaller pieces when popped.
(The authors of this work are Sébastien Moulinet and Mokhtar Adda-Bedia)
By NASA
NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) mission has identified the process that appears to have played a key role in the transition of the Martian climate from an early, warm and wet environment that might have supported surface life to the cold, arid planet Mars is today.
(excerpt - click the link for the complete article and cool video animation)
On Wednesday, Oct. 28 and Friday, Nov. 6, Commander Scott Kelly and Flight Engineer Kjell Lindgren will perform spacewalks in support of space station assembly and maintenance. You can watch both of these events live on NASA Television. But, before you do, here are 7 things to know:
1. What’s the Point of a Spacewalk?
Spacewalks are important events where crew members repair, maintain and upgrade parts of the International Space Station. Spacewalks can also be referred to as an EVA – Extravehicular Activity. On Wednesday, Oct. 28, Commander Scott Kelly and Flight Engineer Kjell Lindgren will complete a spacewalk. During this time they will service the Canadarm2 robotic arm, route cables for a future docking port, and place a thermal cover over a dark matter detection experiment, which is a state-of-the-art particles physics detector that has been attached to the station since 2011.
2. What Do They Wear?
The Extravehicular Mobility Unit (EMU) spacewalking suit weighs around 350 pounds. It’s weightless in space, but mass is still very real. The EMU provides a crew member with life support and an enclosure that enables them to work outside the space station. The suit provides atmospheric containment, thermal insulation, cooling, solar radiation protection and micrometeoroid/orbital debris protection.
3. How Long Are Spacewalks?
Spacewalks typically last around 6 ½ hours, but can be extended to 7 or 8 hours, if necessary. The timeline is designed to accommodate as many tasks as possible, as spacewalks require an enormous amount of work to prepare.
4. What About Eating and Drinking?
Before a spacewalk astronauts eat light, usually something like a protein bar. The spacesuits also have a drink bag inside, and there is a bite valve that allows ready access to water.
5. What About Communication?
Spacewalkers wear a ‘comm’ cap that allows them to constantly communicate with astronauts inside the space station that are helping with the walk, and with mission control. Astronauts also wear a checklist on their left wrist called a “cuff checklist”. This list contains emergency procedures.
6. What About Light?
Something that most people don’t realize about spacewalks is that the crew will experience a sunrise/sunset every 45 minutes. Luckily, their spacesuits are equipped with lights that allow them to see in times of darkness.
7. How Do They Stay Safe?
When on a spacewalk, astronauts use safety tethers to stay close to their spacecraft. One end of the tether is hooked to the spacewalker, while the other end is connected to the vehicle. Another way astronauts stay safe is by wearing a SAFER, which is a Simplified Aid for EVA Rescue. This device is worn like a backpack and uses small jet thrusters to let an astronaut move around in space.
You can watch both of the upcoming spacewalks live on: NASA Television or the NASA App, or follow along on @Space_Station Twitter.
Wednesday, Oct. 28: Coverage begins at 6:30 a.m. EDT. Spacewalk begins at 8:10 a.m.
Friday, Nov. 6: Coverage begins at 5:45 a.m. EDT. Spacewalk begins at 7:15 a.m.
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com
Magnetic Wormhole Created in Lab
“Ripped from the pages of a sci-fi novel, physicists have crafted a wormhole that tunnels a magnetic field through space.
“This device can transmit the magnetic field from one point in space to another point, through a path that is magnetically invisible,” said study co-author Jordi Prat-Camps, a doctoral candidate in physics at the Autonomous University of Barcelona in Spain. “From a magnetic point of view, this device acts like a wormhole, as if the magnetic field was transferred through an extra special dimension.“
The idea of a wormhole comes from Albert Einstein’s theories. In 1935, Einstein and colleague Nathan Rosen realized that the general theory of relativity allowed for the existence of bridges that could link two different points in space-time. Theoretically these Einstein-Rosen bridges, or wormholes, could allow something to tunnel instantly between great distances (though the tunnels in this theory are extremely tiny, so ordinarily wouldn’t fit a space traveler). So far, no one has found evidence that space-time wormholes actually exist.
The new wormhole isn’t a space-time wormhole per se, but is instead a realization of a futuristic “invisibility cloak” first proposed in 2007 in the journal Physical Review Letters. This type of wormhole would hide electromagnetic waves from view from the outside. The trouble was, to make the method work for light required materials that are extremely impractical and difficult to work with, Prat said.
But it turned out the materials to make a magnetic wormhole already exist and are much simpler to come by. In particular, superconductors, which can carry high levels of current, or charged particles, expel magnetic field lines from their interiors, essentially bending or distorting these lines. This essentially allows the magnetic field to do something different from its surrounding 3D environment, which is the first step in concealing the disturbance in a magnetic field.So the team designed a three-layer object, consisting of two concentric spheres with an interior spiral-cylinder. The interior layer essentially transmitted a magnetic field from one end to the other, while the other two layers acted to conceal the field’s existence.”
The Atom and Its Quantum Mirror Image: Physicists Experimentally Produces Quantum-Superpositions, Simply Using a Mirror (click thru for ScienceDaily article)
_________
“This uncertainty about the state of the atom does not mean that the measurement lacks precision,” Jörg Schmiedmayer (TU Vienna) emphasizes. “It is a fundamental property of quantum physics: The particle is in both of the two possible states simultaneousely, it is in a superposition.” In the experiment the two motional states of the atom – one moving towards the mirror and the other moving away from the mirror – are then combined using Bragg diffraction from a grating made of laser light. Observing interference it can be directly shown that the atom has indeed been traveling both paths at once…“
Scientists have developed a novel method to calculate the distances to stars, and it could be useful in helping map the size of galaxies. The study is published in the Monthly Notices of the Royal Astronomical Society.
The researchers from the University of Cambridge examined what are known as “stellar twins.” These are stars that are identical, with exactly the same chemical composition, which can be worked out from their spectra – the type of light they emit. If they were both placed at the same distance from Earth, they would shine with equal brightness.
So the team realized that if the distance to just one of the stars was known, the other could be calculated relatively easily based on how brightly it was shining. The dimmer it is, the further away it is, and vice versa. The method can be used to accurately measure the distance.
“It’s a remarkably simple idea – so simple that it’s hard to believe no one thought of it before,” said lead author Dr Paula Jofre Pfeil, from Cambridge’s Institute of Astronomy, in a statement. “The further away a star is, the fainter it appears in the sky, and so if two stars have identical spectra, we can use the difference in brightness to calculate the distance.”
Read more ~ IFL Science
Photo credit: RealCG Animation Studio. Shutterstock.
One sheet, 15 centimetres in diameter and a few tenths of a millimetre thick can store as much as 1 F, which is similar to the supercapacitors currently on the market. The material can be recharged hundreds of times and each charge only takes a few seconds.
It’s a dream product in a world where the increased use of renewable energy requires new methods for energy storage – from summer to winter, from a windy day to a calm one, from a sunny day to one with heavy cloud cover.
”Thin films that function as capacitors have existed for some time. What we have done is to produce the material in three dimensions. We can produce thick sheets,” says Xavier Crispin, professor of organic electronics and co-author to the article just published in Advanced Science.
Other co-authors are researchers from KTH Royal Institute of Technology, Innventia, Technical University of Denmark and the University of Kentucky.
The material, power paper, looks and feels like a slightly plasticky paper and the researchers have amused themselves by using one piece to make an origami swan – which gives an indication of its strength.
The structural foundation of the material is nanocellulose, which is cellulose fibres which, using high-pressure water, are broken down into fibres as thin as 20 nm in diameter. With the cellulose fibres in a solution of water, an electrically charged polymer (PEDOT:PSS), also in a water solution, is added. The polymer then forms a thin coating around the fibres.
”The covered fibres are in tangles, where the liquid in the spaces between them functions as an electrolyte,” explains Jesper Edberg, doctoral student, who conducted the experiments together with Abdellah Malti, who recently completed his doctorate.
The new cellulose-polymer material has set a new world record in simultaneous conductivity for ions and electrons, which explains its exceptional capacity for energy storage. It also opens the door to continued development toward even higher capacity. Unlike the batteries and capacitors currently on the market, power paper is produced from simple materials – renewable cellulose and an easily available polymer. It is light in weight, it requires no dangerous chemicals or heavy metals and it is waterproof.
The Power Papers project has been financed by the Knut and Alice Wallenberg Foundation since 2012.
”They leave us to our research, without demanding lengthy reports, and they trust us. We have a lot of pressure on us to deliver, but it’s ok if it takes time, and we’re grateful for that,” says Professor Magnus Berggren, director of the Laboratory of Organic Electronics at Linköping University.
The new power paper is just like regular pulp, which has to be dehydrated when making paper. The challenge is to develop an industrial-scale process for this.
”Together with KTH, Acreo and Innventia we just received SEK 34 million from the Swedish Foundation for Strategic Research to continue our efforts to develop a rational production method, a paper machine for power paper,” says Professor Berggren.
Power paper – Four world records
Highest charge and capacitance in organic electronics, 1 C and 2 F (Coulomb and Farad).
Highest measured current in an organic conductor, 1 A (Ampere).
Highest capacity to simultaneously conduct ions and electrons.
Highest transconductance in a transistor, 1 S (Siemens)
Publication:
An Organic Mixed Ion-Electron Conductor for Power Electronics, Abdellah Malti, Jesper Edberg, Hjalmar Granberg, Zia Ullah Khan, Jens W Andreasen, Xianjie Liu, Dan Zhao, Hao Zhang, Yulong Yao, Joseph W Brill, Isak Engquist, Mats Fahlman, Lars Wågberg, Xavier Crispin and Magnus Berggren. Advanced Science, DOI 10.1002/advs.201500305
Linköping University
* (You look inside...) * (Inside the joke book is a quantum physics book.)
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