Top News

Astrophysicists settle cos-mic debate on magnetism of planets and stars

Intense laser experiments provide first evidence that light can stop electrons

New study sheds light on moon’s slow retreat from frozen Earth

Are you rocky or are you gassy

Skyrmions open a door to next-level data storage

Light controls two-atom quantum computation

Humans witnessed fire-cov-ered Earth at end of Ice Age

The way dwarf galaxies move puts a new spin on gal-axy formation

Imagining the possibility of life in a universe without the weak force

Toward a better prediction of solar eruptions

Some of TRAPPIST-1’s plan-ets could have life-friendly atmospheres

Ozone at lower latitudes not recovering, despite ozone hole healing

This Week’s Sky at a Glance, Feb. 10-16, 2018

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Feb. 10-17-24 - Mar. 03

Feb. 10, 2018 Jumada I 23, 1439 AH Volume 8, Issue 06

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Special Read:

Wikipedia has become a sci-ence reference source even though scientists don’t cite it

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Astrophysicists settle cos-mic debate on magnetism of planets and stars

3-D radiation magneto-hydrodynamic FLASH simulation of the experiment, performed on the Mira supercomputer at Argonne National Laboratory. The values demonstrate strong amplifica-tion of the seed magnetic fields by turbulent dynamo. Credit: Petros Tzeferacos/University of Chicago

The universe is highly magnetic, with everything from stars to planets to galaxies producing their own magnetic fields. Astrophysicists have long puzzled over these sur-prisingly strong and long-lived fields, with theories and simulations seeking a mechanism that explains their gen-eration.

Using one of the world’s most powerful laser facilities, a team led by University of Chicago scientists experimen-tally confirmed one of the most popular theories for cos-mic magnetic field generation: the turbulent dynamo. By creating a hot turbulent plasma the size of a penny, that lasts a few billionths of a second, the researchers recorded how the turbulent motions can amplify a weak magnetic field to the strengths of those observed in our sun, distant stars, and galaxies.

The paper, published this week in Nature Communications, is the first laboratory demonstration of a theory, explaining the magnetic field of numerous cosmic bodies, debated by physicists for nearly a century. Using the FLASH physics simulation code, developed by the Flash Center for Com-putational Science at UChicago, the researchers designed an experiment conducted at the OMEGA Laser Facility in Rochester, NY to recreate turbulent dynamo conditions.

Confirming decades of numerical simulations, the exper-iment revealed that turbulent plasma could dramatically boost a weak magnetic field up to the magnitude observed by astronomers in stars and galaxies.

“We now know for sure that turbulent dynamo exists, and that it’s one of the mechanisms that can actually explain magnetization of the universe,” said Petros Tzeferacos, re-search assistant professor of astronomy and astrophysics and associate director of the Flash Center. “This is some-thing that we hoped we knew, but now we do.”

A mechanical dynamo produces an electric current by ro-tating coils through a magnetic field. In astrophysics, dy-namo theory proposes the reverse: the motion of electri-cally-conducting fluid creates and maintains a magnetic field. In the early 20th century, physicist Joseph Larmor proposed that such a mechanism could ...Read More...

Intense laser experiments provide first evidence that light can stop electrons

Illustration of the effect. Credit: Imperial College London/Stuart Mangles

By hitting electrons with an ultra-intense laser, research-ers have revealed dynamics that go beyond ‘classical’ physics and hint at quantum effects.

Whenever light hits an object, some of the light scatters back from the surface of the object. However, if the ob-ject is moving extremely fast, and if the light is incredibly intense, strange things can happen.

Electrons, for example, can be shaken so violently that they actually slow down because they radiate so much energy. Physicists call this process ‘radiation reaction’.

This radiation reaction is thought to occur around objects such as black holes and quasars (supermassive black holes surrounded by a disc of gas). Being able to mea-sure radiation reaction in the lab will therefore provide insights into processes that occur in some of the most extreme environments in the universe.

Radiation reaction is also interesting to physicists study-ing effects beyond ‘classical’ physics, as the equations (known as Maxwell’s equations) that traditionally define the forces acting on objects fall short in these extreme environments.

Now, a team of researchers led by Imperial College London have demonstrated radiation reaction in the lab for the first time. Their results are published today in the journal Physical Review X.

They were able to observe this radiation reaction by colliding a laser beam one quadrillion (a billion million) times brighter than light at the surface of the Sun with a high-energy beam of electrons. The experiment, which required extreme precision and exquisite timing, was achieved using the Gemini laser at the Science and Tech-nology Facilities Council’s Central Laser Facility in the UK. ...Read More...

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New study sheds light on moon’s slow retreat from fro-zen Earth

ESO Illustration Only.

A study led by University of Colorado Boulder researchers provides new insight into the Moon’s excessive equatori-al bulge, a feature that solidified in place over four billion years ago as the Moon gradually distanced itself from the Earth.

The research sets parameters on how quickly the Moon could have receded from the Earth and suggests that the nascent planet’s hydrosphere was either non-existent or still frozen at the time, indirectly supporting the theory of a fainter, weaker Sun that at the time radiated around 30 percent less energy than it does today.

“The Moon’s fossil bulge may contain secrets of Earth’s early evolution that were not recorded anywhere else,” said Shijie Zhong, a professor in CU Boulder’s Department of Physics and the co-lead author of the new research.

“Our model captures two time-dependent processes and this is the first time that anyone has been able to put timescale constraints on early lunar recession.”

The Moon currently recedes from the Earth at a rate of about 4 centimeters per year according to lunar laser rang-ing observations from the Apollo missions. The recession is believed to result from gravitational or tidal interaction between the Earth and Moon. The same process also caus-es Earth’s rotation to slow down and the length of day to increase.

Scientists have theorized that tidal and rotational forces shaped the Moon after it separated from Earth, cooled and moved farther from the planet. The effects of these forc-es flattened the Moon slightly at its poles and solidified a permanent bulge in the lunar crust, creating the feature known as the fossil bulge. About 200 years ago, French mathematician and physicist Pierre-Simon Laplace deter-mined that the Moon’s equatorial bulge was 20 times too large for its one-revolution-per-month rotational rate.

The timing and necessary conditions of this fossil bulge formation have remained largely unknown given that no physical models have ever been ..Read More...

Are you rocky or are you gas-sy

An artist’s impression of a stellar system with three super-Earths.

A star about 100 light years away in the Pisces constella-tion, GJ 9827, hosts what may be one of the most massive and dense super-Earth planets detected to date according to new research led by Carnegie’s Johanna Teske. This new information provides evidence to help astronomers better understand the process by which such planets form.

The GJ 9827 star actually hosts a trio of planets, discov-ered by NASA’s exoplanet-hunting Kepler/K2 mission, and all three are slightly larger than Earth. This is the size that the Kepler mission determined to be most common in the galaxy with periods between a few and several-hun-dred-days.

Intriguingly, no planets of this size exist in our Solar Sys-tem. This makes scientists curious about the conditions under which they form and evolve.

One important key to understanding a planet’s history is to determine its composition. Are these super-Earths rocky like our own planet? Or do they have solid cores surround-ed by large, gassy atmospheres?

To try to understand what an exoplanet is made of, scien-tists need to measure both its mass and its radius, which allows them to determine its bulk density.

When quantifying planets in this way, astronomers have noticed a trend. It turns out that planets with radii greater than about 1.7 times that of Earth are have a gassy enve-lope, like Neptune, and those with radii smaller than this are rocky, like our home planet.

Some researchers have proposed that this difference is caused by photoevaporation, which strips planets of their surrounding envelope of so-called volatiles - substances like water and carbon dioxide that have low boiling points - creating smaller-radius planets. But more information is needed to truly test this theory.

This is why GJ 9827’s three planets are special - with ra-dii of 1.64 (planet b), 1.29 (planet c) and 2.08 (planet d), they span this dividing line between super-Earth (rocky) and sub-Neptune (somewhat gassy) planets. ..Read More...

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Skyrmions open a door to next-level data storage

MAGNETIC KNOTS A skyrmion is a swirl (red) among the atoms of a magnetic material. Here, cones point in the direction of each atom’s magnetization. Skyrmions come in several types; this one, a Néel skyrmion, is found in thin materials.

Like sailors and spelunkers, physicists know the power of a sturdy knot.

Some physicists have tied their hopes for a new genera-tion of data storage to minuscule knotlike structures called skyrmions, which can form in magnetic materials. Incredi-bly tiny and tough to undo, magnetic skyrmions could help feed humankind’s hunger for ever-smaller electronics.

On traditional hard drives, the magnetic regions that store data are about 10 times as large as the smallest skyrmions. Ranging from a nanometer to hundreds of nanometers in diameter, skyrmions “are probably the smallest magnetic systems … that can be imagined or that can be realized in nature,” says physicist Vincent Cros of Unité Mixte de Physique CNRS/Thales in Palaiseau, France.

What’s more, skyrmions can easily move through a ma-terial, pushed along by an electric current. The magnetic knots’ nimble nature suggests that skyrmions storing data in a computer could be shuttled to a sensor that would read off the information as the skyrmions pass by. In con-trast, traditional hard drives read and write data by moving a mechanical arm to the appropriate region on a spinning platter (SN: 10/19/13, p. 28). Those moving parts tend to be fragile, and the task slows down data recall. Scientists hope that skyrmions could one day make for more durable, faster, tinier gadgets.

One thing, however, has held skyrmions back: Until recent-ly, they could be created and controlled only in the frigid cold. When solid-state physicist Christian Pfleiderer and colleagues first reported the detection of magnetic sky-rmions, in Science in 2009, the knots were impractical to work with, requiring very low temperatures of about 30 kelvins (–243° Celsius). Those are “conditions where you’d say, ‘This is of no use for anybody,’ ” says Pfleiderer of the Technical University of Munich.

Skyrmions have finally come out of the cold, though they are finicky and difficult to control. Now, scientists are on the cusp of working out the kinks to create thawed-out skyrmions with all the desired ..Read More...

Light controls two-atom quan-tum computation

Fig. 1: Illustration of the experimental setup: From the right, sin-gle photons (bright red) impinge on an optical cavity in which two atoms (red bullets) are trapped. Because of the strong atom-light field coupling a long-range interaction is mediated between the atoms that can be used to realize gate operations. Following each gate operation, the resulting two-atom state is read out by resonantly probing the cavity transmission and the atomic fluo-rescence. Credit: MPQ, Quantum Dynamics Division

Some powerful rulers of the world may dream of the pos-sibility to get in touch with their colleagues on different continents unnoticed by friends or foes. Someday, new quantum technologies could allow for making these wish-es come true. Physicists around the world are working on the realization of large scale quantum networks in which single light quanta transfer (secret) quantum information to stationary nodes at large distances. Such quantum net-works’ fundamental building blocks are, for example, quan-tum repeaters that counteract the loss of quantum infor-mation over large distances, or quantum logic gates that are necessary for processing quantum information.

Now, a team of scientists around Professor Gerhard Rem-pe, director at the Max Planck Institute of Quantum Optics and head of the Quantum Dynamics Division, has demon-strated the feasibility a new concept for a quantum gate (Phys. Rev. X 8, 011018, 6 February 2018). Here, photons impinging on an optical cavity mediate an interaction be-tween two atoms trapped inside. This interaction is the basis for performing characteristic gate operations be-tween the atoms, for example the operation as a CNOT gate or the generation of entanglement. The new method offers a variety of advantages: for example, the gate op-erations take place within microseconds which is an asset for quantum information processing. Also, the gate mech-anism can be applied to other experimental platforms, and the two-atom gate can serve as a building block in a quan-tum repeater.

Core element of the experiment (see figure 1) is an asym-metric high-finesse optical resonator, consisting of a high-reflection mirror (left) and a mirror with a finite trans-mission (right). Two electrically neutral rubidium atoms are trapped in the centre of the cavity. Each atom carries a qubit, i.e. quantum information that is encoded in the su-perposition of two stable ground states ....Read More...

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Humans witnessed fire-cov-ered Earth at end of Ice Age

Image via Jayson Coil

A new study suggests that, on a day about 12,800 years ago, Earth collided with fragments of a disintegrating comet, igniting fires across the globe. The large study, of geochemical and isotopic markers from 170 different sites around the world, was published in two papers in the Jour-nal of Geology on February 1, 2018 (here and here).

At the time, the Earth had emerged from an ice age. Things were warming up, and the glaciers had retreated. In a statement, the researchers imagined what it might have been like for humans at the time:

Out of nowhere, the sky was lit with fireballs. This was followed by shock waves.

Fires rushed across the landscape, and dust clogged the sky, cutting off the sunlight. As the climate rapidly cooled, plants died, food sources were snuffed out, and the gla-ciers advanced again. Ocean currents shifted, setting the climate into a colder, almost “ice age” state that lasted an additional thousand years.

Finally, the researchers said, the climate began to warm again. This world had fewer large animals, evidenced by, for example, completely different kinds of spear points left behind by North American people of that time.

The researchers believe the data suggests the disaster was touched off when Earth collided with fragments of a disintegrating comet that was roughly 62 miles (100 km) in diameter — the remnants of which persist within our so-lar system to this day.

Adrian Melott, professor of Physics and Astronomy at Uni-versity of Kansas is a study author. Melott said in a state-ment:

The hypothesis is that a large comet fragmented and the chunks impacted the Earth, causing this disaster. A number of different chemical signatures — carbon dioxide, nitrate, ammonia and others — all seem to indicate that an astonishing 10 percent of the Earth’s land surface, or about 10 million square kilometers [3.9 million square miles], was consumed by fires. ..Read More...

The way dwarf galaxies move puts a new spin on galaxy for-mation

RIGHT ROUND Dwarf galaxies near the giant galaxy Centaurus A, shown here in a composite of images from three different tele-scopes, seem to orbit it in an unexpectedly organized loop. WFI (Optical)/ESO, A. Weiss et al. (Submillimetre)/APEX/ESO/MPI-fR, R. Kraft et al. (X-ray)/CfA/CXC/NASA

Small galaxies are playing a game of ring around the ros-ie. Dwarf galaxies have been caught following each other around the distant galaxy Centaurus A in a coordinated loop, rather than zipping around randomly as theory pre-dicts they should.

The discovery could spell trouble for standard theories of cosmology, including the role of enigmatic dark matter in galaxy formation, astronomers say in the Feb. 2 Science.

These observations suggest “we are missing something, some important piece” in understanding dark matter and how galaxies form, says coauthor Oliver Müller, an astron-omer at the University of Basel in Switzerland.

Simulations of how large-scale cosmic structures form suggest that galaxies are connected by a vast network of dark matter, the evasive substance that makes up most of the universe’s matter but interacts with regular matter only via gravity (SN Online: 10/11/17). The largest galax-ies grow where threads of dark matter intersect, according to those simulations.

Smaller, dwarf galaxies travel toward the intersections along long dark matter filaments, like cars on roads lead-ing into a city. In the simulations, these dark matter thor-oughfares connect major galactic hubs from all directions, so small galaxies should zip around the central galaxy at random.

But they don’t — at least not according to what’s been ob-served in the local universe. Studies show that both the Milky Way and the nearby Andromeda Galaxy host satel-lites that orbit in the same plane and the same direction, similar to how the planets in the solar system orbit the sun. “The Milky Way and Andromeda are good systems to show that there is something weird going on,” Müller says. Scientists had wondered if the effect was limited to these two galaxies, which are both in the ...Read More...

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Toward a better prediction of solar eruptions

The result shows the presence of a reinforced multilayer mag-netic cage (orange and pink) in which the magnetic rope (blue) develops during the last hours before the eruption. Credit: © Tahar Amari et al. / Centre de physique théorique (CNRS/École Polytechnique).

A single phenomenon may underlie all solar eruptions, according to researchers from the CNRS, École Polytech-nique, CEA and INRIA in an article featured on the cover of the February 8 issue of Nature. They have identified the presence of a confining ‘cage’ in which an entangled magnetic ‘rope’ forms, causing solar eruptions. It is the resistance of this cage to the attack of the rope that de-termines the power and type of the upcoming flare. This work has enabled the scientists to develop a model capa-ble of predicting the maximum energy that can be released during a solar flare, which could have potentially devastat-ing consequences for the Earth.

Just as on Earth, storms and hurricanes sweep through the atmosphere of the sun. These phenomena are caused by a sudden, violent reconfiguration of the solar magnetic field, and are characterized by an intense release of energy in the form of light and particle emissions, and sometimes by the ejection of a bubble of plasma. Studying these phe-nomena, which take place in the corona (the outermost region of the sun), will enable scientists to develop fore-casting models, just as they do for the Earth’s weather. This should limit our technological vulnerability to solar eruptions, which can impact a number of sectors such as electricity distribution, GPS and communications systems.

In 2014, researchers showed that a characteristic struc-ture, an entanglement of magnetic force lines twisted together like a rope, gradually appears in the days pre-ceding a solar flare. However, until recently, they had only observed this rope in eruptions that ejected bubbles of plasma. In this new study, the researchers studied other types of flare, the models of which are still being debated, by undertaking a more thorough analysis of the solar co-rona, a region where the sun’s atmosphere is so thin and hot that it is difficult to measure the solar magnetic field there. They did this by measuring the stronger magnetic field at the surface of the sun, and then using these data to reconstruct what was happening in the solar corona....Read More....

Imagining the possibility of life in a universe without the weak force

Credit: CC0 Public Domain

A team of researchers at the University of Michigan has conducted a thought experiment regarding the nature of a universe that could support life without the weak force. In their paper uploaded to the ArXiv preprint server, the researchers suggest life could be possible in such an alter-native universe, but it would definitely be different from what we observe in ours.

Physicists have debated the possibility of the existence of alternate universes for some time, though there is no evidence they exist. In this new thought experiment, the team at UM wondered if one or more of the laws of phys-ics that we have discovered in this universe might not ex-ist in others—if they do exist. Because it would be hard to imagine a universe that could exist without gravity and the strong and electromagnetic forces, the team instead focused on the weak force—the one behind such things as neutrons decaying into protons.

The team wondered what a universe without the weak force would look like. To visualize it, they created a sim-ulation of such a universe starting from the Big Bang. In the simulation, matter was still created and condensed into stars, but from there on, things would be different, because in our universe, the weak force is responsible for the creation of the heavier elements. In a universe without the weak force, the existence of anything other than stars would require more free protons and fewer neutrons (be-cause they could not decay). In such a universe, neutrons and protons could link up to make deuterium.

Stars fueled by deuterium instead of hydrogen, the re-searchers note, would still shine, they would just look dif-ferent—likely redder and larger. But such stars could also serve as the source of all of the elements in the periodic table prior to iron, and the stellar winds could carry them out into space. If planets happened to form, they further note, they could hold water made from deuterium rather than hydrogen—and it is not impossible to imagine, they suggest, life forms made with deuterium water. ...Read More...

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Some of TRAPPIST-1’s planets could have life-friendly atmo-spheres

PEERING THROUGH THE MIST Starlight filtering through the atmospheres of the planets orbiting TRAPPIST-1 (shown here in an artist’s illustration of the two innermost worlds) can give scientists a clue to the planets’ habitability. Scientists have now probed the atmospheres of the four middle planets, which could be well-suited for life. J. de Wit/MIT STScI/ESA/NASA

It’s still too early to pack your bags for TRAPPIST-1. But two new studies probe the likely compositions of the seven Earth-sized worlds orbiting the cool, dim star, and some are looking better and better as places to live (SN: 3/18/17, p. 6).

New mass measurements suggest that the septet proba-bly have rocky surfaces and possibly thin atmospheres, re-searchers report February 5 in Astronomy & Astrophysics. For at least three of the planets, those atmospheres don’t appear to be too hot for life, many of these same research-ers conclude February 5 in Nature Astronomy.

TRAPPIST-1 is about 40 light-years from Earth, and four of its planets lie within or near the habitable zone, the range where temperatures can sustain liquid water. That makes these worlds tempting targets in the search for extrater-restrial life (SN: 12/23/17, p. 25)

One clue to potential habitability is a planet’s mass — some-thing not precisely nailed down in previous measurements of the TRAPPIST-1 worlds. Mass helps determine a planet’s density, which in turn provides clues to its makeup. High density could indicate that a planet doesn’t have an atmo-sphere. Low density could indicate that a planet is shroud-ed in a puffy, hydrogen-rich atmosphere that would cause a runaway greenhouse effect.

Using a new computer technique that accounts for the planets’ gravitational tugs on each other, astronomer Si-mon Grimm of the University of Bern in Switzerland and his colleagues calculated the seven planets’ masses with five to eight times better precision than before. Those mea-surements suggest that the innermost planet probably has a thick, viscous atmosphere like Venus, Grimm says. The other six, which may be covered in ice or oceans, may have more life-friendly atmospheres. The fourth planet from the star has the same density as Earth and ...Read More...

Ozone at lower latitudes not recovering, despite ozone hole healing

Illustration Only.

The ozone layer - which protects us from harmful ultravi-olet radiation - is recovering at the poles, but unexpected decreases in part of the atmosphere may be preventing recovery at lower latitudes.

Global ozone has been declining since the 1970s ow-ing to certain man-made chemicals. Since these were banned, parts of the layer have been recovering, particu-larly at the poles.

However, the new result, published in the European Geosciences Union journal Atmospheric Chemistry and Physics, finds that the bottom part of the ozone layer at more populated latitudes is not recovering. The cause is currently unknown.

Ozone is a substance that forms in the stratosphere - the region of the atmosphere between about 10 and 50 km altitude, above the troposphere that we live in. It is produced in tropical latitudes and distributed around the globe.

A large portion of the resulting ozone layer resides in the lower part of the stratosphere. The ozone layer ab-sorbs much of the UV radiation from the Sun, which, if it reaches the Earth’s surface, can cause damage to DNA in plants, animals and humans.

In the 1970s, it was recognised that chemicals called CFCs, used for example in refrigeration and aerosols, were destroying ozone in the stratosphere. The effect was worst in the Antarctic, where an ozone ‘hole’ formed.

In 1987, the Montreal Protocol was agreed, which led to the phase-out of CFCs and, recently, the first signs of recovery of the Antarctic ozone layer. The upper strato-sphere at lower latitudes is also showing clear signs of recovery, proving the Montreal Protocol is working well.

However, despite this success, scientists have today re-vealed that stratospheric ozone is likely not recovering at lower latitudes, between 60N ...Read More...

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Special Read:

Wikipedia has become a science reference source even though scientists don’t cite it

SCIENCE IN ACTION The section of a Wikipedia page on the synthesis of hydrastine was part of a project that showed how Wikipe-dia topics might end up in scientific studies. Farknot Architect/shutterstock; Wikimedia Commons

Wikipedia: The settler of dinnertime disputes and the savior of those who cheat on trivia night. Quick, what country has the Nile’s headwaters? What year did Gershwin write “Rhapsody in Blue”? Wikipedia has the answer to all your burning trivia questions — including ones about science.

With hundreds of thousands of scientific entries, Wikipedia offers a quick reference for the molecular formula of Zoloft, who the inventor of the 3-D printer is and the fact that the theory of plate tectonics is only about 100 years old. The website is a gold mine for science fans, science bloggers and scientists alike. But even though scientists use Wikipedia, they don’t tend to admit it. The site rarely ends up in a paper’s citations as the source of, say, the history of the gut-brain axis or the chemical formula for polyvinyl chloride.

But scientists are browsing Wikipedia just like everyone else. A recent analysis found that Wikipedia stays up-to-date on the latest research — and vocabulary from those Wikipedia articles finds its way into scientific papers. The results don’t just reveal the Wiki-habits of the ivory tower. They also show that the free, widely available information source is playing a role in research progress, especially in poorer countries.

Teachers in middle school, high school and college drill it in to their students: Wikipedia is not a citable source. Anyone can edit Wikipedia, and articles can change from day to day — sometimes by as little as a comma, other times being com-pletely rewritten overnight. “[Wikipedia] has a reputation for being untrustworthy,” says Thomas Shafee, a biochemist at La Trobe University in Melbourne, Australia.

But those same teachers — even the college professors — who warn students away from Wikipedia are using the site themselves. “Academics use Wikipedia all the time because we’re human. It’s something everyone is doing,” says Doug Hanley, a macroeconomist at the University of Pittsburgh.

And the site’s unreliable reputation may be unwarranted. Wikipedia is not any less consistent than Encyclopedia Bri-tannica, a 2005 Nature study showed (a conclusion that the encyclopedia itself vehemently objected to). Citing it as a source, however, is still a bridge too far. “It’s not respected like academic resources,” Shafee notes.

Academic science may not respect Wikipedia, but Wikipedia certainly loves science. Of the roughly 5.5 million articles, half a million to a million of them touch on scientific topics. And constant additions from hundreds of thousands of editors mean that entries can be very up to date on the latest scientific literature.

How recently published findings affect Wikipedia is easy to track. They’re cited on Wikipedia, after all. But does the relationship go the other way? Do scientific posts on Wikipedia worm their way into the academic ...Read More...

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This Week’s Sky at a GlanceFeb. 10-16, 2018

Feb 11 Su 18:16 Moon Apogee: 405700 km 18:46 Moon-Saturn: 2.7° S 20:40 Mars-Antares: 5.1° NFeb 12 Mo 03:21 Moon South Dec.: 20° SFeb 15 Th 01:11 Moon Descending NodeFeb 16 Fr 00:51 Partial Solar Eclipse - Not Visible from UAE 01:05 New Moon

SCASS Arduino Workshop (Feb. 10-17-24; Mar. 03, 2018)