Top News

Early Earth had a hazy, methane-filled atmosphere

Could fast radio bursts be powering alien probes?

’Going deep’ to measure Earth’s rotational effects

Gigantic Jupiter-type plan-et reveals insights into how planets evolve

New material helps record data with light

Quantum shortcuts cannot bypass the laws of thermo-dynamics

Distant galaxies are dom-inated by gas and stars so where is the Dark Matter

Scientists identify a black hole choking on stardust

Running away from Ein-stein

European team announces superconductivity break-through

Ultrashort light pulses for fast ‘lightwave’ computers

From the butterfly’s wing to the tornado: Predicting turbulence

This Week’s Sky at a Glance, Mar. 19 -25

Special Activities:1. Lecture: Exoplanets

March 22, 20172. Observatory Open House :

March 23, 2017 (18:30 - 20:30)

March 18, 2017 Jumada II 19, 1438 AH Volume 7, Issue11

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Special Read:

Aiming Higher: High School Students Build Flight Hard-ware Bound for Space

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Early Earth had a hazy, meth-ane-filled atmosphere

A new research paper describes a period more than 2.4 billion years ago, when Earth’s atmosphere was filled with a thick, methane-rich haze much like Saturn’s moon Titan, seen here in an image taken by NASA’s Cassini spacecraft in 2013. Image courtesy NASA/JPL-Caltech/Space Science Institute

More than 2.4 billion years ago, Earth’s atmosphere was inhospitable, filled with toxic gases that drove wildly fluc-tuating surface temperatures. Understanding how today’s world of mild climates and breathable air took shape is a fundamental question in Earth science.

New research from the University of Maryland, the Univer-sity of St. Andrews, NASA’s Jet Propulsion Laboratory, the University of Leeds and the Blue Marble Space Institute of Science suggests that long ago, Earth’s atmosphere spent about a million years filled with a methane-rich haze. This haze drove a large amount of hydrogen out of the atmo-sphere, clearing the way for massive amounts of oxygen to fill the air. This transformation resulted in an atmo-sphere much like the one that sustains life on Earth today.

The group’s results, published March 13, 2017 in the early online edition of the Proceedings of the National Acade-my of Sciences, propose a new contributing cause for the Great Oxidation Event, which occurred 2.4 billion years ago, when oxygen concentrations in the Earth’s atmo-sphere increased more than 10,000 times.

“The transformation of Earth’s air from a toxic mix to a more welcoming, oxygen-rich atmosphere happened in a geological instant,” said James Farquhar, a professor of geology at UMD and a co-author of the study. Farquhar also has an appointment at UMD’s Earth System Science Interdisciplinary Center. “With this study, we finally have the first complete picture of how methane haze made this happen.”

The researchers used detailed chemical records and so-phisticated atmospheric models to reconstruct atmospher-ic chemistry during the time period immediately before the Great Oxidation Event.

Their results suggest that ancient bacteria - the only life on Earth at the time - produced massive amounts of meth-ane that reacted to fill the air with a ...Read More...

Could fast radio bursts be powering alien probes?

An artist’s illustration of a light-sail powered by a radio beam (red) generated on the surface of a planet. The leakage from such beams as they sweep across the sky would appear as Fast Radio Bursts (FRBs), similar to the new population of sources that was discovered recently at cosmological distances. Image courtesy M. Weiss and CfA.

The search for extraterrestrial intelligence has looked for many different signs of alien life, from radio broadcasts to laser flashes, without success. However, newly published research suggests that mysterious phenomena called fast radio bursts could be evidence of advanced alien technology. Specifically, these bursts might be leakage from planet-sized transmitters powering interstellar probes in distant galaxies.

“Fast radio bursts are exceedingly bright given their short duration and origin at great distances, and we haven’t identified a possible natural source with any confidence,” said theorist Avi Loeb of the Harvard-Smithsonian Center for Astrophysics. “An artificial origin is worth contemplat-ing and checking.”

As the name implies, fast radio bursts are millisec-ond-long flashes of radio emission. First discovered in 2007, fewer than two dozen have been detected by gigantic radio telescopes like the Parkes Observatory in Australia or the Arecibo Observatory in Puerto Rico. They are inferred to originate from distant galaxies, billions of light-years away.

Loeb and his co-author Manasvi Lingam (Harvard Univer-sity) examined the feasibility of creating a radio trans-mitter strong enough for it to be detectable across such immense distances.

They found that, if the transmitter were solar powered, the sunlight falling on an area of a planet twice the size of the Earth would be enough to generate the needed energy. Such a vast construction project is well beyond our technology, but within the realm of possibility accord-ing to the laws of physics. Lingam and Loeb also consid-ered whether such a transmitter would be viable from an engineering perspective, or whether the tremendous energies involved would melt any underlying structure. Again, they found that a water-cooled device twice the size of Earth could withstand the heat. ...Read More,..

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’Going deep’ to measure Earth’s rotational effects

Radiofrequency discharge of the GINGERino ring laser. A heli-um-neon plasma is generated in the middle of one side of the ring through a pyrex capillary. Image courtesy Belfi et al.

Researchers in Italy hope to measure Earth’s rotation us-ing a laser-based gyroscope housed deep underground, with enough experimental precision to reveal measurable effects of Einstein’s general theory of relativity. The ring laser gyroscope (RLG) technology enabling these Earth-based measurements provide, unlike those made by ref-erencing celestial objects, inertial rotation information, re-vealing fluctuations in the rotation rate from the grounded reference frame.

A group from the Italian National Institute for Nuclear Physics’ (INFN) Laboratori Nazionali del Gran Sasso (LNGS) are working with a research program aimed at measuring the gyroscopic precession Earth undergoes due to a rel-ativistic effect called the Lense-Thirring effect. This pro-gram, called Gyroscopes in General Relativity (GINGER), would eventually use an array of such highly sensitive RLGS. For now, they have successfully demonstrated its prototype, GINGERino, and acquired a host of additional seismic measurements necessary in their efforts.

In this week’s journal Review of Scientific Instruments, from AIP Publishing, the group reports their successful in-stallation of the single-axis GINGERino instrument inside the INFN’s subterranean laboratory LNGS, and its ability to detect local ground rotational motion.

Ultimately, GINGER aims to measure Earth’s rotation rate vector with a relative accuracy of better than one part per billion to see the miniscule Lense-Thirring effects.

“This effect is detectable as a small difference between the Earth’s rotation rate value measured by a ground based observatory, and the value measured in an inertial reference frame,” said Jacopo Belfi, lead author and a re-searcher working for the Pisa section of INFN.

“This small difference is generated by the Earth’s mass and angular momentum and has been foreseen by Einstein’s general theory of relativity. From the experimental point of view, one needs to measure ...Read More...

Gigantic Jupiter-type plan-et reveals insights into how planets evolve

Simulated image of the HD 106906 stellar debris disk, showing a ring of rocky planet-forming material.

UCLA, Carnegie Institution astrophysicists get rare peek at a baby solar system 300 light-years away

An enormous young planet approximately 300 light-years from Earth has given astrophysicists a rare glimpse into planetary evolution.

The planet, known as HD 106906b, was discovered in 2014 by a team of scientists from the U.S., the Nether-lands and Italy. It is 11 times the mass of Jupiter and is extremely young by celestial standards - not more than 13 million years old, compared with our solar system’s 4.6 billion years.

“This is such a young star; we have a snapshot of a baby star that just formed its planetary system - a rare peek at the final stage of planet formation,” said Smadar Naoz, a UCLA assistant professor of physics and astronomy, and a co-author of the study.

Another of the planet’s unusual characteristics is its dis-tance from its star. Astronomers believe that the vast ma-jority of planets outside of our solar system exist inside a vast dusty disk of debris relatively close to the center of the solar system. But HD 106906b is far beyond its so-lar system’s disk - so far away that it takes 1,500 years for the planet to orbit its star. HD 106906b is currently at least 650 times as far from its star as the Earth is from our sun.

“Our current planet formation theories do not account for a planet beyond its debris disk,” Naoz said.

The study’s lead author is Erika Nesvold, a postdoctoral fellow at the Carnegie Institution for Science whom Naoz mentors. She wrote software called Superparticle-Method Algorithm for Collisions in Kuiper belts and debris disks, or SMACK, that allowed the researchers to create a mod-el of the planet’s orbital path - a critical step because HD 106906b orbits so slowly that the researchers can barely see it move. ...Read More...

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New material helps record data with light

The way of how the light with different wavelengths influences on a MOF crystal: different types of excitons are showed in red and blue (left). Image of crystals (right). Image courtesy ITMO University.

Russian physicists with their colleagues from Europe through changing the light parameters, learned to gener-ate quasiparticles - excitons, which were fully controllable and also helped to record information at room temperature.

These particles act as a transitional form between pho-tons and electrons so the researchers believe that with excitons, they will be able to create compact optoelectron-ic devices for rapid recording and processing an optical signal. The proposed method is based on use of a special class of materials called metal-organic frameworks. The study appeared in Advanced Materials.

To simplify the description of complex effects in quantum mechanics, scientists have introduced a concept of quasi-particles. One of them which is called exciton is an “elec-tron - hole” pair, which provides energy transfer between photons and electrons.

According to the scientific community, this mediation of quasiparticles will help to combine optics with electronics to create a fundamentally new class of equipment - more compact and energy efficient. However, all exciton demo devices either operate only at low temperature, or are dif-ficult to manufacture which inhibits their mass adoption.

In the new study, the scientists from ITMO University in Saint Petersburg, Leipzig University in Germany and Eind-hoven University of Technology in the Netherlands could generate excitons at room temperature by changing the light parameters. The authors also managed to control the quasiparticles with ultra-high sensitivity of about hun-dreds of femtoseconds (10-13 s). Finally, they developed an easy method for data recording with excitons. This all became possible through the use of an individual class of materials called metal-organic frameworks.

Metal-organic frameworks (MOF) synthesized at ITMO University, have a layered structure. Between the layers, there is a physical attraction called van der Waals force. To prevent the plates from uncontrollably coming together, the interlayer space is filled with an organic ...Read More...

Quantum shortcuts cannot bypass the laws of thermody-namics

Credit: CC0 Public Domain

Over the past several years, physicists have developed quantum shortcuts that speed up the operation of quan-tum systems. Surprisingly, some of these shortcuts the-oretically appear to enable systems to operate nearly instantaneously while using no extra energy—a clear vi-olation of the second law of thermodynamics. Although physicists have known that something is amiss, so far the solution to this predicament has been unclear.

Now in a new study, physicists have shown that quantum shortcuts are subject to a trade-off between speed and cost, so that the faster a quantum system evolves, the higher the energetic cost of implementing the shortcut. In accordance with the laws of thermodynamics, an infinitely fast speed would be impossible since it would require an infinite amount of energy.

The physicists, Steve Campbell at Queen’s University Bel-fast in the UK and the University of Milan in Italy, along with Sebastian Deffner at the University of Maryland Bal-timore County in the US, have published a paper on the trade-off between cost and speed in quantum shortcuts in a recent issue of Physical Review Letters.

“Some recently proposed methods to control quantum systems, called shortcuts to adiabaticity (STA), appear to be energetically for free, and even more concerning there was nothing to say they couldn’t be achieved in vanishing-ly small times,” Campbell told Phys.org. “That something wasn’t quite right led us to more explicitly consider what happens when these techniques are applied.”

To do this, the scientists applied the quantum speed lim-it—a fundamental upper bound on the speed at which a quantum system can operate, which arises due to the Heisenberg uncertainty principle. Since the quantum speed limit is a consequence of this fundamental princi-ple, it must apply to all STAs, and so it should prohibit them from operating in arbitrarily short times.

“By calculating the quantum speed limit, we showed that the faster you want to manipulate a system using an STA, the higher the thermodynamic cost,” ..Read More...

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Distant galaxies are dominat-ed by gas and stars so where is the Dark Matter

Observations of the six galaxies with KMOS and SINFONI. For each galaxy, the left column shows the distribution of the total surface brightness in the Ha line. The right column gives the ve-locity map. All galaxies show a clear rotation pattern, with blue areas moving towards the observer and red parts away from the observer. Image courtesy MPE.

New observations of rotating galaxies at the peak epoch of galaxy formation, 10 billion years ago, surprisingly show that these massive, star-forming galaxies are completely dominated by baryonic or “normal” mass with dark matter playing a much smaller role in comparable regions of their outer disks than in the local universe.

The international group of researchers led by the Max Planck Institute for Extraterrestrial Physics mapped the rotation curves of six galaxies to distances of ~65,000 light years from their centres and found that their rotation velocities are not constant but drop with radius.

These findings are supported by observations of more than 200 further galaxies, where different estimates of their dynamical state also indicate a high baryonic mass fraction. In addition, the analysis shows that these early galaxies had a much thicker disk with turbulent motion ac-counting for part of the dynamical support. These findings are published in a paper in the journal Nature as well as three accompanying papers in the Astrophysical Journal.

Over the past few decades, many different studies of gal-axies in the local universe have shown the existence and importance of so-called “dark matter”. While normal, or “baryonic”, matter can be seen as brightly shining stars or luminous gas and dust, dark matter interacts with normal matter only through gravity. In particular it is responsible for flat rotation curves in spiral galaxies, i.e. rotation veloc-ities that are constant or increasing with radius.

An international team of astronomers, led by Reinhard Genzel at the Max Planck Institute for Extraterrestrial Physics, have now obtained deep imaging spectroscopy of several hundred massive, star-forming galaxies in the dis-tant universe (at redshift 0.6 to 2.6). This allowed the re-searchers to extract the rotation curves, which give valu-able constraints on the mass distribution ...Read More...

Scientists identify a black hole choking on stardust

Illustration Only.

Data suggest black holes swallow stellar debris in bursts. In the center of a distant galaxy, almost 300 million light years from Earth, scientists have discovered a supermas-sive black hole that is “choking” on a sudden influx of stel-lar debris.

In a paper published in Astrophysical Journal Letters, re-searchers from MIT, NASA’s Goddard Space Flight Center, and elsewhere report on a “tidal disruption flare” - a dra-matic burst of electromagnetic activity that occurs when a black hole obliterates a nearby star. The flare was first discovered on Nov. 11, 2014, and scientists have since trained a variety of telescopes on the event to learn more about how black holes grow and evolve.

The MIT-led team looked through data collected by two different telescopes and identified a curious pattern in the energy emitted by the flare: As the obliterated star’s dust fell into the black hole, the researchers observed small fluctuations in the optical and ultraviolet (UV) bands of the electromagnetic spectrum. This very same pattern repeat-ed itself 32 days later, this time in the X-ray band.

The researchers used simulations of the event performed by others to infer that such energy “echoes” were pro-duced from the following scenario: As a star migrated close to the black hole, it was quickly ripped apart by the black hole’s gravitational energy.

The resulting stellar debris, swirling ever closer to the black hole, collided with itself, giving off bursts of optical and UV light at the collision sites. As it was pulled further in, the colliding debris heated up, producing X-ray flares, in the same pattern as the optical bursts, just before the debris fell into the black hole.

“In essence, this black hole has not had much to feed on for a while, and suddenly along comes an unlucky star full of matter,” says Dheeraj Pasham, the paper’s first author and a postdoc in MIT’s Kavli Institute for Astrophysics and Space Research. “What we’re seeing is, this stellar material is not just continuously being fed onto the black hole, but it’s interacting with itself - stopping and going, stopping and going. This is telling us that the black ...Read More...

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European team announc-es superconductivity break-through

”This new material (Eurotapes) could be used to make more po-tent and lighter wind turbines,” Xavier Obradors said, predicting it will make it possible to manufacture wind turbines one day with double the potency than existing ones

European researchers said Tuesday they had developed a cheaper and more efficient superconducting tape which could one day be used to double the potency of wind tur-bines.

Eurotapes, a European research project on superconductiv-ity—the ability of certain materials to channel electricity with zero resistance and very little power loss—has pro-duced 600 metres (1,968 feet) of the tape, said the coor-dinator of the project, Xavier Obradors, of the Institute of Materials Science of Barcelona.

“This material, a copper oxide, is like a thread that conducts 100 times more electricity than copper. With this thread you can for example make cables to transport much more electricity or generate much more intense magnetic fields than today,” he told AFP.

“This new material could be used to make more potent and lighter wind turbines,” he added, predicting it will make it possible to manufacture wind turbines one day with dou-ble the potency of existing ones.

In the long run the project could “revolutionise the produc-tion of renewable energy,” the Institute said in a statement.

Eurotapes is a four-year project involving world leaders in the field of superconductivity from nine European na-tions—Austria, Belgium, Britain, France, Germany, Italy, Ro-mania, Slovakia and Spain.

The European Union covers the bulk of its budget of 20 million euros ($21 million).

When an electric current passes through a conductor such as copper and silver, part of the charge is lost as heat, a loss that increases with the distance the charge travels.

In superconductivity—first discovered in mercury in 1911—electrical resistance suddenly drops to zero ...Read More...

Running away from Einstein

Einstein’s theory of gravity may have to be rewritten, after researchers at the University of St Andrews found a gigan-tic ring of galaxies darting away from us much faster than predicted.

This 10 million light year-wide ring made up of small gal-axies is expanding rapidly like a mini Big Bang. The team believe our neighbouring galaxy, Andromeda, once flew past our own galaxy at close range, creating a sling-shot of several small galaxies.

Dr Hongsheng Zhao, Reader in the School of Physics and Astronomy and co-author of the paper, published in Month-ly Notices of the Royal Astronomical Society by Oxford Uni-versity Press, said: “If Einstein’s gravity were correct, our galaxy would never come close enough to Andromeda to scatter anything that fast.”

If true, the discovery would force a new understanding of gravity and about our cosmos, as such a galactic flyby only makes sense if gravity weakens more slowly as galaxies drift apart than mainstream thinking suggests.

Indranil Banik, the PhD student who led the study, said: “The ring-like distribution is very peculiar. These small gal-axies are like a string of raindrops flung out from a spin-ning umbrella. I found there is barely a 1 in 640 chance for randomly distributed galaxies to line up in the observed way. I traced their origin to a dynamical event when the Universe was only half its present age.”

This tsunami-like wake in the sky was likely stirred up by a near-miss of the speeding Andromeda galaxy with our own galaxy, the Milky Way. The two massive galaxies al-ways orbited each other in a plane and would have scat-tered dwarf galaxies in their paths, perhaps explaining why the speeding dwarfs are in a plane also containing the Milky Way and Andromeda.

Mr Banik added: “In Einstein’s gravity paradigm, hypothet-ical dark matter is always invoked. Such a high speed re-quires 60 times the mass we see in the stars of the Milky Way and Andromeda. However, the friction between their huge halos of dark matter would result in them merging rather than flying 2.5 million light ...Read More...

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Ultrashort light pulses for fast ‘lightwave’ computers

Image credit: Credit: ORNL.gov

Extremely short, configurable “femtosecond” pulses of light demonstrated by an international team could lead to future computers that run up to 100,000 times faster than today’s electronics.

The researchers, including engineers at the University of Michigan, showed that they could control the peaks within the laser pulses and also twist the light.

The method moves electrons faster and more efficiently than electrical currents—and with reliable effects on their quantum states. It is a step toward so-called “lightwave electronics” and, in the more distant future, quantum com-puting, said Mackillo Kira, U-M professor of electrical en-gineering and computer science who was involved in the research.

Electrons moving through a semiconductor in a computer, for instance, occasionally run into other electrons, releas-ing energy in the form of heat. But a concept called light-wave electronics proposes that electrons could be guided by ultrafast laser pulses. While high speed in a car makes it more likely that a driver will crash into something, high speed for an electron can make the travel time so short that it is statistically unlikely to hit anything.

“In the past few years, we and other groups have found that the oscillating electric field of ultrashort laser puls-es can actually move electrons back and forth in solids,” said Rupert Huber, professor of physics at the University of Regensburg who led the experiment. “Everybody was immediately excited because one may be able to exploit this principle to build future computers that work at un-precedented clock rates—10 to a hundred thousand times faster than state-of-the-art electronics.”

But first, researchers need to be able to control electrons in a semiconductor. This work takes a step toward this ca-pability by mobilizing groups of electrons inside a semi-conductor crystal using terahertz radiation—the part of the electromagnetic spectrum between microwaves and infra-red light. ...Read More...

From the butterfly’s wing to the tornado: Predicting tur-bulence

An analyzed snapshot of a moment of turbulent flow, in this case, an exact coherent structure (ECS). Credit: Georgia Tech / Schatz / Grigoriev

An old adage holds that the flap of a butterfly’s wing in Brazil can trigger a tornado in Texas weeks later. Though chaos theory says it’s basically impossible to compute exactly how that might happen, scientists have made advances in applying math to predict the phenomenon behind it called turbulence.

Recent progress by physicists from the Georgia Institute of Technology could one day help sharpen weather fore-casts and extend their range by making better use of masses of weather and climate data.

Turbulence can curve as a puff of air, swirl past a river bend or churn as a hurricane, and though its curlicues may appear random, turbulence lays down signature pat-terns that the physicists are investigating. They have developed a simple mathematical model that has helped them show how turbulent flows will evolve over inter-vals.

And, in a novel experiment, they verified their predic-tions physically in a two-dimensional turbulent flow pro-duced in a lab.

‘Butterfly Effect’ catchphrase

The new Georgia Tech research befits the origins of that adage.

It was coined more than 55 years ago by MIT meteorol-ogy professor Edward Lorenz after he established that tiny forces influenced major weather enough to throw long-range forecasts for a loop. The title of his paper, “Predictability: Does the Flap of a Butterfly’s Wing in Bra-zil Set Off a Tornado in Texas?” morphed into the well-known catchphrase. Michael Schatz and Roman Grigor-iev, professors in Georgia Tech’s School of Physics, along with graduate researchers Balachandra Suri and Jeffrey Tithof, published their research results ...Read More...

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Special Read:

Aiming Higher: High School Students Build Flight Hardware Bound for Space

Students in the Machine Tool technology classroom at Austin High School in Decatur, Alabama work on various projects as part of the High Schools United with NASA to Create Hardware - HUNCH - program, designed to encourage students to pursue careers in the aerospace industry. Image courtesy NASA.

Students at an Alabama high school have done so well in a NASA program that they are now making parts for use on the International Space Station.

For more than 50 years, NASA has sponsored programs to get students interested in the aerospace industry. One program called HUNCH - High Schools United with NASA to Create Hardware - challenges students to use machining, welding and other skills learned in class to build exact replicas of the hardware on the space station. These twin ver-sions are added to full-sized models of the station on the ground. Astronauts and flight controllers use these mock-ups for ground training before a mission.

“We realized early in the station program that we needed a version on the ground before we flew in to space,” said Bob Zeek, HUNCH co-founder and program manager at NASA’s Marshall Space Flight Center in Huntsville, Alabama.

“At the same time, we wanted to get kids who are good at machining, welding, or other technical skills involved with NASA. A four-year degree is good for some, but we need technical people, too. Machining, computer-aided-design drafting, welding, computer electronics - all the things we do in HUNCH are preparing these students for the future and helping the agency at the same time.”

HUNCH has been a part of the curriculum for the machine tool technology class at Austin High School in Decatur, Ala-bama, since 2010. Bill Gibson is the school’s Machine Tool Technology instructor and a fierce advocate for this kind of hands-on training.

“The first year of the program, we did a couple of simple designs for their training modules like locker panels and racks,” he said. “Every year, the students have gotten better, so we get more advanced and challenging designs.”

The program has brought students into his class who may not have initially considered machining as a career.

“It’s very rewarding for me and for these students,” Gibson said. “They are very enthusiastic and work very diligently on these projects. Motivation is not a problem. The thought of an astronaut putting their hands on the work they do in class really brings out their best.”

It was the consistent high quality of the work that made Zeek and the HUNCH program consider letting students take their talents to the next level. The students were challenged to build two items. One was a set of bolts that will hold lockers of scientific experiments in place on the space station.

The other is a holder for a new brush cleaning tool for use during spacewalks. The tools were delivered to the space station on the tenth SpaceX cargo resupply mission, which launched Feb. 19, and the bolts are already used on assem-bled lockers that will launch on a future resupply mission. ...Read More...

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This Week’s Sky at a Glance:Mar. 19-25

Mar. 20 Third Quarter Moon 19:58Mar. 20 Spring Equinox 14:29Mar. 23 Mercury at perihelion 18:00Mar. 25 Venus at inferior conjunction 15:00Mar. 25 Moon at descending node 19:41

Special Activities:

1. Lecture: Title: Exoplanets Speaker: Mr. Marwan A. Shwaiki Date: March 22, 2017 Time: 14:00 - 15:00 Location: SCASS Auditorium

2. Observatory Open House : Target Objects: Mercury - Mars - Sirius - Mizar (Binary) - Orion Nebula (M 42) - Rosette Nebula (NGC 2244) - Crab Nebula (M 37) M 67 (Open cluster) - Date: March 23, 2017 Time: 18:30 - 20:30