Thirteen-year-old Julia Derzay of Pewaukee, Wisconsin, wins a trip to the Northeast Astronomy Forum & Telescope Show with her entry for Astronomy’s 2015 Youth Essay Contest.
Telescopes give shape to furious black hole winds
This discovery that the winds blow in all directions has given astronomers their first opportunity to measure the strength of these ultra-fast winds and prove they are powerful enough to inhibit the host galaxy’s ability to make new stars.
Imeline taevas
Mõnikord on Päike ümbritsetud heleda ringiga, mille sisemine äär võib olla punane ja välimine sinine. Nurk ringjoone ja selle keskpunkti vahel on 22°, mistõttu kutsutakse seda 22° haloks. (Seda nurka saab kergesti mõõta. Selleks tuleb käsi välja sirutada ning sõrmed niimoodi laiali ajada, et peopesa jääb väljapoole. See taevaosa, mis jääb sirgele joonele pöidla ja […]
Three holes in a bottle?the answer
In my article (Featonby 2015 Phys. Educ. 50 123), three holes were drilled in a large bottle of
water, but which hole had the greatest range of water?
Modern replication of Eratosthenes? measurement of the circumference of Earth
Twenty-two hundred years ago, the Greek scientist Eratosthenes measured the circumference of the
Earth. This paper describes an experiment to replicate Eratosthenes? experiment with observers
located in Australia and New Zealand. The most accurate ci…
Spinning tops on a gentle incline?the question
How does the behaviour of a spinning top differ when it is set to spin on a gentle incline?
The Earth?s magnetic field fuels inter-disciplinary education
There is no doubt that integrated concepts inspire students and take learning to a new level. As we
fly, we fly through the magnetic field of the Earth. We used the concepts involved in flying to
develop an exercise that bonds geology, physics and li…
Polarization of physics on global courses
Since October 2010, the Chemistry–Biology Combined Major Program, an international course taught in
English at Osaka University, has been teaching small classes (no more than 20 in size). We present
data from the Force Concept Inventory (FCI) given…
How tidal forces cause ocean tides in the equilibrium theory
We analyse why it is erroneous to think that a tidal bulge is formed by pulling the water surface
directly up by a local vertical tidal force. In fact, ocean tides are caused by the global effect of
the horizontal components of the tidal forces.
The Earth’s magnetic field fuels inter-disciplinary education
There is no doubt that integrated concepts inspire students and take learning to a new level. As we
fly, we fly through the magnetic field of the Earth. We used the concepts involved in flying to
develop an exercise that bonds geology, physics and li…
Quantitative experiments to explain the change of seasons
The science education literature shows that students have difficulty understanding what causes the
seasons. Incorrect explanations are often due to a lack of knowledge about the physical mechanisms
underlying this phenomenon. To address this, we pres…
Spinning tops on a gentle incline—the question
How does the behaviour of a spinning top differ when it is set to spin on a gentle incline?
News
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The butterfly effect for physics laboratories
A low-cost chaos dynamics lab is developed for quantitative demonstration of the butterfly effect
using a magnetic pendulum. Chaotic motion is explored by recording magnetic time series. Students
analyze the data in Excel ® to investigate the butter…
Experimenting with a spinning disk
Almost everyone will have observed a spinning coin fall to a shuddering stop. How and why does it do
that? Several experiments are described, suitable for a student project, to help motivate an
understanding of the rotational dynamics involved.
A simple experiment showing the determination of the magnetic dipole moment of a permanent disc magnet
We propose a simple experiment to estimate the magnetic dipole moment of a neodymium disc magnet.
The experiment employs a precision digital balance and a 1 m ruler to measure the force between two
magnets. The magnetic dipole moment is determined …
Thinking in terms of sensors: personification of self as an object in physics problem solving
How can physics teachers help students develop consistent problem solving techniques for both simple
and complicated physics problems, such as those that encompass objects undergoing multiple forces
(mechanical or electrical) as individually portraye…
Interview: Interviewing the interviewer
Peter Campbell talks to David Smith, Physics Education board member and longstanding editor of the
People section, about his teaching career, special interests and related activities.
Waste not, want not
Sadly, modern society has developed very wasteful habits over the last few decades: consumer
products, food and energy are perphaps waste items that are most obvious. Attempting to show how we
can counteract wasteful habits, this article (a) makes re…
Understanding thermal equilibrium through activities
Thermal equilibrium is a basic concept in thermodynamics. In India, this concept is generally
introduced at the first year of undergraduate education in physics and chemistry. In our earlier
studies (Pathare and Pradhan 2011 Proc. episteme-4 Int. Con…
Three holes in a bottle—the answer
In my article (Featonby 2015 Phys. Educ. 50 123), three holes were drilled in a large bottle of
water, but which hole had the greatest range of water?
Modern replication of Eratosthenes’ measurement of the circumference of Earth
Twenty-two hundred years ago, the Greek scientist Eratosthenes measured the circumference of the
Earth. This paper describes an experiment to replicate Eratosthenes’ experiment with observers
located in Australia and New Zealand. The most accurate …
The usefulness of magnets for teaching gravitational acceleration
This paper presents the simple apparatus and steps to demonstrate the gravitational acceleration
point of the vector, which is advantageous for students who lack reading comprehension.
Motion of a charged particle in a constant and uniform electromagnetic field
This paper focuses on the use of software developed by the authors that allows the visualization of
the motion of a charged particle under the influence of magnetic and electric fields in 3D, at a
level suitable for introductory physics courses. The …
Using an air thermometer to estimate the gas constant
The air thermometer, widely used in physics laboratories to show the relationship between volume and
temperature, can also be used to obtain values for the gas constant and hence Avogadro’s number.
Using a very low cost, home-made air thermometer c…
Physics of swinging a striking implement
The act of swinging an object such as a hammer or a tennis racket involves the application of forces
and torques in a manner that is intuitively obvious to the person performing the task, but is
probably much less obvious to the average physics stude…
Google Earth science
Google Earth has made a wealth of aerial imagery available online at no cost to users. We examine
some of the potential uses of that data in illustrating basic physics and astronomy, such as finding
the local magnetic declination, using landmarks suc…
Reviews
Description unavailable
Understanding resonance graphs using Easy Java Simulations (EJS) and why we use EJS
This paper reports a computer model simulation created using Easy Java Simulation (EJS) for learners
to visualize how the steady-state amplitude of a driven oscillating system varies with the frequency
of the periodic driving force. The simulation sh…
NASA, ESA Telescopes Give Shape to Furious Black Hole Winds
NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR) and ESA’s (European Space Agency) XMM-Newton telescope are showing that fierce winds from a supermassive black hole blow outward in all directions — a phenomenon that had been suspec…
ESA’s Biomass satellite goes ahead

Following the initial selection in 2013 for Biomass to become ESA’s seventh Earth Explorer mission and the completion of preparatory activities, ESA Member States yesterday gave the green light for its full implementation for launch in 2020.
Constraint on a Varying Proton-Electron Mass Ratio 1.5 Billion Years after the Big Bang
Author(s): J. Bagdonaite, W. Ubachs, M. T. Murphy, and J. B. Whitmore
The spectrum of a distant quasar reveals no sign of changes in the mass ratio of the proton and the electron over 12 billion years, constraining dark energy theories.
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[Phys. Rev. Lett. 114, 071301] Published Thu Feb 19, 2015
Earth from Space

Join us Friday, 20 February, at 10:00 CET for the ‘Earth from Space’ video programme. This week features a Sentinel-1A mosaic of Estonia
A close call of 0.8 light-years
Astronomers have identified the closest known flyby of a star to our solar system.
A close call of 0.8 light-years
Astronomers have identified the closest known flyby of a star to our solar system.
Dark matter guides growth of supermassive black holes
There seems to be a mysterious link between the amount of dark matter a galaxy holds and the size of its central black hole.
21. mai 1946: Louis Slotinist saab „deemonsüdamiku” teine ohver
1989. aasta filmi „Fat Man and Little Boy” üks kõige haaravamaid stseene ei ole Trinity katse meisterlik kujutamine. See on hoopis stseen, kus väljamõeldud füüsik Michael Merriman keerab vussi kriitilisuse katse ja saab selle käigus surmavalt kiiritada. Merrimani tegelaskujus on ühendatud kaks tõelist füüsikut, kelle surm tegi neist teistlaadi sõjaohvrid. Kriitilisuse uuringud Los Alamose riiklikus […]
Mars hills hide icy past
A complex network of isolated hills, ridges and small basins spanning 1400 km on Mars is thought to hide large quantities of water-ice.
Happy Chinese New Year

Wishing the world’s Chinese population safe travels for their celebrations of the year of the sheep
Läbimurre “õhulaserite” tekitamises?
Kuidas saada teada, milline on õhu koostis mõne korstna läheduses või kilomeetrite kõrgusel maapinnast, kui teil ei ole kasutada lennukeid, õhupalle või taevatreppi? Selgub, et õhumolekulid saab panna laserina kiirgama ja seda ka kauge maa tagant, laserivalguse neeldumise kaudu saab omakord teada atmosfääri koostise. Alexandre Laurain ja tema kolleegid Arizona ülikoolist on leidnud mooduse, kuidas […]
Kinesin-8 Motors Improve Nuclear Centering by Promoting Microtubule Catastrophe
Author(s): Matko Glunčić, Nicola Maghelli, Alexander Krull, Vladimir Krstić, Damien Ramunno-Johnson, Nenad Pavin, and Iva M. Tolić
A motor protein called kinesin-8 helps keep a cell’s nucleus centered by controlling the length of the tubular structures that connect it with the cell wall.
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[Phys. Rev. Lett. 114, 078103] Published Wed Feb 18, 2015
New SPHERE instrument shows its power
The instrument has been used to search for a brown dwarf expected to be orbiting the unusual double star V471 Tauri — and found nothing.
Dawn captures sharper images of Ceres
As the spacecraft delivers better images and other data, the science team will be investigating the nature and composition of the dwarf planet.
Try before you fly
Technology image of the week: an ESA-led team rode this Polish centrifuge to prepare for a technology-testing parabolic flight
Dawn Captures Sharper Images of Ceres
Craters and mysterious bright spots are beginning to pop out in the latest images of Ceres from NASA’s Dawn spacecraft.
Cool ride!
Thanks to space, some Parisian Metro riders now enjoy a very high-tech commute. A satellite spin-off is paving the way for more comfortable journeys.;
Final goodbye
Human Spaceflight and Operations image of the week: the International Space Station and the last Automated Transfer Vehicle streaking through the sky over Europe
Rosetta in 2015
From close encounters to distant flybys, discover what’s in store for the Rosetta mission as the comet increases in activity
A new way to view Titan: “Despeckle” it
The technique produces radar images of Titan’s surface that are much clearer and easier to look at than the views to which scientists and the public have grown accustomed.
Mystery Mars plume baffles scientists
The plumes were seen rising to altitudes of over 155 miles (250 kilometers) above the same region of Mars on both occasions.
SMOS on acid

With fundamental changes happening to the chemistry of the world’s oceans, salinity information from ESA’s SMOS mission is being used with other Earth observation data to obtain information on ‘the other carbon dioxide problem’ – ocean acidification.
Close encounter
Space science image of the week: Rosetta swoops in for the closest comet flyby yet
Mystery Mars plume baffles scientists
Plumes seen reaching high above the surface of Mars are causing a stir among scientists studying the atmosphere on the Red Planet.
<i>Interstellar</i> technology throws light on spinning black holes
The computed code used to generate the movie’s iconic images revealed that when a camera is close up to a rapidly spinning black hole, peculiar surfaces in space create more than a dozen images of individual stars and of the thin, bright plane of the g…
ALMA sees super stellar nurseries at heart of Sculptor Galaxy
The research suggests that it’s not just the number of stellar nurseries that sets the throttle for a galaxy to create new stars, but also what kind of stellar nurseries are present.
ATV undocking

Time-lapse showing the departure of ATV Georges Lemaître from the International Space Station on 14 February
Kuidas näha väga kiireid laetud osakesi?
Kui laetud osake, näiteks elektron, liigub läbi dielektriku kiirusega, mis on suurem valguse kiirusest selles keskkonnas, siis tekib kiirgus, mida nimetatakse selle avastaja järgi Cherenkovi kiirguseks. Näiteks vees paiknevate tuumareaktorite kiiratav sinine valgus on justnimelt Cherenkovi kiirgus ja selle järgi on võimalik beeta-kiirguse olemasolu kindlaks teha (vt pilti). Sellist, kiirete laetud osakeste poolt tekitatud kiirgust […]
Last ATV reentry leaves legacy for future space exploration

ESA’s fifth automated cargo ferry completed its mission to the International Space Station today when it reentered the atmosphere and burned up safely over an uninhabited area of the southern Pacific Ocean.
Miks on Higgs’i boson nagu täringud?
Higgsi bosoni avastamise aegu kirjutas Andi Hektor Horisondis: “Hurraa! Mõõtmistulemused näitavad, et uus ATLAS ja CMS mõõdavad signaali olulisusega 5-sigma. Mhh, ühmatab nüüd mitteosakestefüüsik! Mida see peaks tähendama? Mitteosakestefüüsikute keeles tähendab see tõenäosust umbes 1/1000000, et tegu ei ole uue osakesega. Osakestefüüsikud on kokku leppinud, et sellist olukorda nimetatakse osakese avastuseks.” Mis on see salapärane […]
Rohelise laseri valgus
Rohelise laseri valgus läheb läbi kolme klaasi, vasakult paremale. Esimeses klaasis on canola õli, teises on vesi, kolmandas oliivõli. Õlis osa kõrge energiaga (rohelisi) footoneid neeldub ning kiirgub madalama energiaga footoneid (fluorestsents), canola õli annab oranzi, oliiviõli punase fluorestsentsi. Veeklaasis näeme rohelist kiirt, mis on lihtsalt rohelise valguse hajumine vees.
‘Pale Blue Dot’ Images Turn 25
NASA’s Voyager 1 spacecraft showed its love for the solar system, including Earth, with these images on Feb. 14, 1990.
Neutral Naturalness from Orbifold Higgs Models
Author(s): Nathaniel Craig, Simon Knapen, and Pietro Longhi A new class of models, rooted in ideas of extra dimensions of space, is proposed that protect the Higgs mass from large loop corrections.[Phys. Rev. Lett. 114, 061803] Published Fri Feb 13, 2015
Laser Filamentation as a New Phase Transition Universality Class
Author(s): W. Ettoumi, J. Kasparian, and J.-P. Wolf A powerful laser beam separates into many smaller filaments that undergo a phase transition similar to fluid percolating through a porous material.[Phys. Rev. Lett. 114, 063903] Published Fri Feb 13,…
Week In Images
Our week through the lens: 9-13 February 2015
Happy Valentine’s
Choose your favourite image and send an e-card
Exploded star blooms like a cosmic flower
Astronomers are discovering that some type Ia supernova explosions may not be as symmetric as previously thought.
Mismatched twin stars spotted in the delivery room
The discovery of these stellar twins could provide invaluable insight into the formation and evolution of massive stars, close binaries, and star nurseries.
ATV-5 mission ends
Follow the last moments of ESA’s fifth and final Automated Transfer Vehicle as it leaves a legacy for future space exploration
Follow ESA spacecraft
See the ground tracks of ESA spacecraft and satellites on our interactive map, including the final voyage of Europe’s Automated Transfer Vehicle
LHC kaks aastat kestnud remont hakkab läbi saama
Suur Hadronite Põrguti (Large Hadron Collider ehk LHC) lülitati välja 14. veebruaril 2013, pärast kolm aastat kestnud tööd. Sellest alates on sajad insenerid ja tehnikud parandanud ja täiustanud LHC kiirendeid ja eksperimente, et valmistada need ette tööks kõrgematel energiatel. LHC taaskäivitamine on planeeritud käesolevale, 2015.aastale. Plaanis on eksperimendid, kus põrkuvate osakeste energia on 13TeV (6,5 […]
Bending of Light in Quantum Gravity
Author(s): N. E. J. Bjerrum-Bohr, John F. Donoghue, Barry R. Holstein, Ludovic Planté, and Pierre Vanhove
Theorists calculate how quantum gravity effects could alter the bending of light induced by massive objects.
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[Phys. Rev. Lett. 114, 061301] Published Thu Feb 12, 2015
Earth from Space

Join us Friday, 13 February, at 10:00 CET for the ‘Earth from Space’ video programme. This week features Las Vegas and Lake Mead in the United States
Astronomers catch multiple-star system in first stages of formation
Direct observations of this process give strong support to one of several suggested pathways to producing such systems.
The Very Large Array finds unexpected “storm” at galaxy’s core
The discovery provides important insight on how supermassive black holes can have a catastrophic effect on the galaxies in which they reside.
IXV safely recovered
IXV is hoisted onboard the Nos Aries recovery ship. Looking in great shape, it will now travel back to Europe for further analysis
Suured holograafilised ekraanid ei ole enam ulme
Holograafia ei ole tegelikult surnud, kujutlus holograafilistest avataridest, kes meie asemel koosolekul istuvad või koju kätte toodud ruumilisest maailmast toidab endiselt terve armee teadlaste ja inseneride meeli, kunstnikest, disaineritest ja müügimeestest rääkimata. Seda küll, et kuuekümnendatel suurte lootustega alustatud arendused jäid toppama tehnoloogia taha, see lihtsalt ei olnud veel piisavalt kaugele arenenud. Nüüd on teadlased […]
Open source virtual reality platform takes on 13 new partners
An open source virtual reality platform reports 13 new partners. This is the Open Source Virtual Reality (OSVR) ecosystem, envisioned as the platform that can bring together companies doing work in a number of areas of virtual reality. OSVR aims to set…
Tumeaine leitud ka Linnutee südames
Rahvusvaheline astronoomide meeskond on leidnud uusi tõendeid selle kohta, et Linnutee keskmes on märkimisväärses koguses tumeainet. See tulemus kinnitab teadlaste seniseid hinnanguid, edasises töös loodetakse tumeaine jaotus meie galaktikas veel täpsemalt kindlaks teha. Esimesed vihjed tumeaine olemasolule said teadlased galaktikate pöörlemise uurimisest. Selgus nimelt, et galaktikad pöörlevad palju kiiremini, kui võiks ennustada eeldades, et neid […]
A New Way to View Titan: ‘Despeckle’ It
Views of Saturn’s hazy moon Titan now appear much sharper, thanks to a technique that greatly improves radar images taken by NASA’s Cassini spacecraft.
Liftoff to splashdown

Relive IXV’s 100 minute reentry success from liftoff at Europe’s Spaceport to splashdown in the Pacific Ocean on 11 February
IXV awaits ship
Job done, IXV floats in the Pacific Ocean awaiting the Nos Aries recovery ship that will hoist it on board for its journey back to Europe for further analysis
Madis Ollikainen: tänavune Tamkivi Reaalteaduste Fondi stipendiaat
Madis Ollikainen erineb peaaegu kõiges veel hiljuti laialt levinud füüsiku stereotüübist. Ei, füüsikud ei ole ujedad ja hajameelsed tüübid, kes teavad küll hästi füüsikat, aga muus elus on üsna saamatud. Seda küll, et Madis teab ametile kohaselt füüsikat, aga ta on ka aktiivne, sirge selja ja jutuga maailmakodanik. Eriti hea on tõdeda, et ta ei […]
Friedrich Kaasik: tänavune Tamkivi Reaalteaduste Fondi stipendiaat
On hea kuulda, et Tamkivi Reaalteaduste Fondi tänavune stipendiaat on Friedrich Kaasik. Eesti Füüsika Selts teab Friedrichit kui olulist ja asjalikku tegutsejat teaduse populariseerimise rindel. Ta on andnud oma väga väärtusliku panuse nii Teadusbussis, õpikodades, kui ka Teaduslaagrites. Õnnitleme ja soovime jätkuvat jõudu nii teadlasena kui ka teaduse äraseletajana. Loe asjakohast intervjuud fondi kodulehelt.
ESA experimental spaceplane completes research flight

An experimental vehicle to develop an autonomous European reentry capability for future reusable space transportation has completed its mission. ESA’s Intermediate eXperimental Vehicle flew a flawless reentry and splashed down in the Pacific Ocean just west of the Galapagos islands.
Postinflationary Higgs Relaxation and the Origin of Matter-Antimatter Asymmetry
Author(s): Alexander Kusenko, Lauren Pearce, and Louis Yang
A new explanation for why matter dominates in our Universe rests on the idea that the Higgs field hasn’t been constant in time.
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[Phys. Rev. Lett. 114, 061302] Published Wed Feb 11, 2015
Vega VV04 liftoff

Watch the liftoff of Vega VV04 with ESA’s experimental spaceplane at 13:40 GMT (14:40 CET) on 11 February
IXV in pictures
View the latest pictures of ESA’s reentry mission lasting 100 minutes. IXV will test in flight the lastest technologies and critical systems for future space exploration
Experimental spaceplane completes research flight
The European Space Agency’s Intermediate eXperimental Vehicle flew a flawless reentry and splashed down in the Pacific today.
Mars Rover Nearing Marathon Achievement
Since landing on Mars in January 2004, NASA’s Mars Exploration Rover Opportunity has driven nearly as far as a marathon footrace.
Smile, and the Universe Smiles With You
An upbeat-looking galaxy cluster appears to smile at us in a newly released image from the NASA/ESA Hubble Space Telescope.
National Academy of Engineering Adds Two JPL Members
Two JPL researchers have been elected to the National Academy of Engineering, the highest professional distinction for engineers.
Why Comets Are Like Deep Fried Ice Cream
Origins of crunchy crusts on comets explained in new laboratory research.
ATV to bid farewell to Space Station for last time

ESA’s last Automated Transfer Vehicle will leave the International Space Station on Saturday for its final solo voyage, setting course for a fiery demise that will mark the end of its mission and the programme.
In the hot seat

Human spaceflight and operations image of the week: The Control Centre that will command Europe’s largest spacecraft, the Automated Transfer Vehicle, when it undocks from the International Space Station on Saturday
Classical-to-Quantum Transition with Broadband Four-Wave Mixing
Author(s): Rafi Z. Vered, Yaakov Shaked, Yelena Ben-Or, Michael Rosenbluh, and Avi Pe’er
A key question of quantum optics is how nonclassical biphoton correlations at low power evolve into classical coherence at high power. Direct observation of the crossover from quantum to classical behavior is desirable, but difficult due to the lack of adequate experimental techniques that cover the…
[Phys. Rev. Lett. 114, 063902] Published Tue Feb 10, 2015
Universality Far from Equilibrium: From Superfluid Bose Gases to Heavy-Ion Collisions
Author(s): J. Berges, K. Boguslavski, S. Schlichting, and R. Venugopalan A new universality class for many-body systems far from equilibrium is conjectured, providing a link between disparate physical systems ranging from hot plasmas to cold gases.[Phy…
Observation of Two New Ξ_{b}^{-} Baryon Resonances
Author(s): R. Aaij et al. (LHCb Collaboration) Researchers report the detection of two new subatomic particles made of three quarks from each of the possible quark families.[Phys. Rev. Lett. 114, 062004] Published Tue Feb 10, 2015
ESA astronaut Thomas Pesquet’s space colleagues announced
The next crews to visit the International Space Station, including ESA astronaut Thomas Pesquet, have been announced.
IXV gets ready
ESA’s spaceplane is set for its 100 minute mission tomorrow, 11 February. See how it was done in the timelapse video
NASA spacecraft completes 40,000 Mars orbits
The orbiter is investigating seasonal and longer-term changes, including some warm-season flows that are the strongest evidence so far for liquid water on Mars today.










